ViewVC Help
View File | Revision Log | Show Annotations | Download File
/cvs/AnyEvent/lib/AnyEvent/Handle.pm
(Generate patch)

Comparing AnyEvent/lib/AnyEvent/Handle.pm (file contents):
Revision 1.210 by root, Thu Dec 30 01:53:15 2010 UTC vs.
Revision 1.242 by root, Wed Dec 10 04:29:33 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
128=item on_connect => $cb->($handle, $host, $port, $retry->()) 128=item on_connect => $cb->($handle, $host, $port, $retry->())
129 129
130This callback is called when a connection has been successfully established. 130This callback is called when a connection has been successfully established.
131 131
132The peer's numeric host and port (the socket peername) are passed as 132The peer's numeric host and port (the socket peername) are passed as
133parameters, together with a retry callback. 133parameters, together with a retry callback. At the time it is called the
134read and write queues, EOF status, TLS status and similar properties of
135the handle will have been reset.
134 136
135If, for some reason, the handle is not acceptable, calling C<$retry> 137If, for some reason, the handle is not acceptable, calling C<$retry> will
136will continue with the next connection target (in case of multi-homed 138continue with the next connection target (in case of multi-homed hosts or
137hosts or SRV records there can be multiple connection endpoints). At the 139SRV records there can be multiple connection endpoints). The C<$retry>
138time it is called the read and write queues, eof status, tls status and 140callback can be invoked after the connect callback returns, i.e. one can
139similar properties of the handle will have been reset. 141start a handshake and then decide to retry with the next host if the
142handshake fails.
140 143
141In most cases, you should ignore the C<$retry> parameter. 144In most cases, you should ignore the C<$retry> parameter.
142 145
143=item on_connect_error => $cb->($handle, $message) 146=item on_connect_error => $cb->($handle, $message)
144 147
164with active (but unsatisfiable) read watchers (C<EPIPE>) or I/O errors. In 167with active (but unsatisfiable) read watchers (C<EPIPE>) or I/O errors. In
165cases where the other side can close the connection at will, it is 168cases where the other side can close the connection at will, it is
166often easiest to not report C<EPIPE> errors in this callback. 169often easiest to not report C<EPIPE> errors in this callback.
167 170
168AnyEvent::Handle tries to find an appropriate error code for you to check 171AnyEvent::Handle tries to find an appropriate error code for you to check
169against, but in some cases (TLS errors), this does not work well. It is 172against, but in some cases (TLS errors), this does not work well.
170recommended to always output the C<$message> argument in human-readable 173
171error messages (it's usually the same as C<"$!">). 174If you report the error to the user, it is recommended to always output
175the C<$message> argument in human-readable error messages (you don't need
176to report C<"$!"> if you report C<$message>).
177
178If you want to react programmatically to the error, then looking at C<$!>
179and comparing it against some of the documented C<Errno> values is usually
180better than looking at the C<$message>.
172 181
173Non-fatal errors can be retried by returning, but it is recommended 182Non-fatal errors can be retried by returning, but it is recommended
174to simply ignore this parameter and instead abondon the handle object 183to simply ignore this parameter and instead abondon the handle object
175when this callback is invoked. Examples of non-fatal errors are timeouts 184when this callback is invoked. Examples of non-fatal errors are timeouts
176C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>). 185C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>).
224If an EOF condition has been detected but no C<on_eof> callback has been 233If an EOF condition has been detected but no C<on_eof> callback has been
225set, then a fatal error will be raised with C<$!> set to <0>. 234set, then a fatal error will be raised with C<$!> set to <0>.
226 235
227=item on_drain => $cb->($handle) 236=item on_drain => $cb->($handle)
228 237
229This sets the callback that is called when the write buffer becomes empty 238This sets the callback that is called once when the write buffer becomes
230(or immediately if the buffer is empty already). 239empty (and immediately when the handle object is created).
231 240
232To append to the write buffer, use the C<< ->push_write >> method. 241To append to the write buffer, use the C<< ->push_write >> method.
233 242
234This callback is useful when you don't want to put all of your write data 243This 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 244into 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 256many 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 257file 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> 258will be invoked (and if that one is missing, a non-fatal C<ETIMEDOUT>
250error will be raised). 259error will be raised).
251 260
252There are three variants of the timeouts that work independently 261There are three variants of the timeouts that work independently of each
253of each other, for both read and write, just read, and just write: 262other, for both read and write (triggered when nothing was read I<OR>
263written), just read (triggered when nothing was read), and just write:
254C<timeout>, C<rtimeout> and C<wtimeout>, with corresponding callbacks 264C<timeout>, C<rtimeout> and C<wtimeout>, with corresponding callbacks
255C<on_timeout>, C<on_rtimeout> and C<on_wtimeout>, and reset functions 265C<on_timeout>, C<on_rtimeout> and C<on_wtimeout>, and reset functions
256C<timeout_reset>, C<rtimeout_reset>, and C<wtimeout_reset>. 266C<timeout_reset>, C<rtimeout_reset>, and C<wtimeout_reset>.
257 267
258Note that timeout processing is active even when you do not have 268Note 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 269outstanding read or write requests: If you plan to keep the connection
260idle then you should disable the timeout temporarily or ignore the timeout 270idle then you should disable the timeout temporarily or ignore the
261in the C<on_timeout> callback, in which case AnyEvent::Handle will simply 271timeout in the corresponding C<on_timeout> callback, in which case
262restart the timeout. 272AnyEvent::Handle will simply restart the timeout.
263 273
264Zero (the default) disables this timeout. 274Zero (the default) disables the corresponding timeout.
265 275
266=item on_timeout => $cb->($handle) 276=item on_timeout => $cb->($handle)
277
278=item on_rtimeout => $cb->($handle)
279
280=item on_wtimeout => $cb->($handle)
267 281
268Called whenever the inactivity timeout passes. If you return from this 282Called whenever the inactivity timeout passes. If you return from this
269callback, then the timeout will be reset as if some activity had happened, 283callback, then the timeout will be reset as if some activity had happened,
270so this condition is not fatal in any way. 284so this condition is not fatal in any way.
271 285
354already have occured on BSD systems), but at least it will protect you 368already have occured on BSD systems), but at least it will protect you
355from most attacks. 369from most attacks.
356 370
357=item read_size => <bytes> 371=item read_size => <bytes>
358 372
359The initial read block size, the number of bytes this module will try to 373The initial read block size, the number of bytes this module will try
360read during each loop iteration. Each handle object will consume at least 374to read during each loop iteration. Each handle object will consume
361this amount of memory for the read buffer as well, so when handling many 375at least this amount of memory for the read buffer as well, so when
362connections requirements). See also C<max_read_size>. Default: C<2048>. 376handling many connections watch out for memory requirements). See also
377C<max_read_size>. Default: C<2048>.
363 378
364=item max_read_size => <bytes> 379=item max_read_size => <bytes>
365 380
366The maximum read buffer size used by the dynamic adjustment 381The maximum read buffer size used by the dynamic adjustment
367algorithm: Each time AnyEvent::Handle can read C<read_size> bytes in 382algorithm: Each time AnyEvent::Handle can read C<read_size> bytes in
411appropriate error message. 426appropriate error message.
412 427
413TLS mode requires Net::SSLeay to be installed (it will be loaded 428TLS mode requires Net::SSLeay to be installed (it will be loaded
414automatically when you try to create a TLS handle): this module doesn't 429automatically when you try to create a TLS handle): this module doesn't
415have a dependency on that module, so if your module requires it, you have 430have a dependency on that module, so if your module requires it, you have
416to add the dependency yourself. 431to add the dependency yourself. If Net::SSLeay cannot be loaded or is too
432old, you get an C<EPROTO> error.
417 433
418Unlike TCP, TLS has a server and client side: for the TLS server side, use 434Unlike TCP, TLS has a server and client side: for the TLS server side, use
419C<accept>, and for the TLS client side of a connection, use C<connect> 435C<accept>, and for the TLS client side of a connection, use C<connect>
420mode. 436mode.
421 437
477callback. 493callback.
478 494
479This callback will only be called on TLS shutdowns, not when the 495This callback will only be called on TLS shutdowns, not when the
480underlying handle signals EOF. 496underlying handle signals EOF.
481 497
482=item json => JSON or JSON::XS object 498=item json => L<JSON>, L<JSON::PP> or L<JSON::XS> object
483 499
484This is the json coder object used by the C<json> read and write types. 500This is the json coder object used by the C<json> read and write types.
485 501
486If you don't supply it, then AnyEvent::Handle will create and use a 502If you don't supply it, then AnyEvent::Handle will create and use a
487suitable one (on demand), which will write and expect UTF-8 encoded JSON 503suitable one (on demand), which will write and expect UTF-8 encoded
504JSON texts (either using L<JSON::XS> or L<JSON>). The written texts are
505guaranteed not to contain any newline character.
506
507For security reasons, this encoder will likely I<not> handle numbers and
508strings, only arrays and objects/hashes. The reason is that originally
509JSON was self-delimited, but Dougles Crockford thought it was a splendid
510idea to redefine JSON incompatibly, so this is no longer true.
511
512For protocols that used back-to-back JSON texts, this might lead to
513run-ins, where two or more JSON texts will be interpreted as one JSON
488texts. 514text.
489 515
516For this reason, if the default encoder uses L<JSON::XS>, it will default
517to not allowing anything but arrays and objects/hashes, at least for the
518forseeable future (it will change at some point). This might or might not
519be true for the L<JSON> module, so this might cause a security issue.
520
521If you depend on either behaviour, you should create your own json object
522and pass it in explicitly.
523
524=item cbor => L<CBOR::XS> object
525
526This is the cbor coder object used by the C<cbor> read and write types.
527
528If you don't supply it, then AnyEvent::Handle will create and use a
529suitable one (on demand), which will write CBOR without using extensions,
530if possible.
531
490Note that you are responsible to depend on the JSON module if you want to 532Note that you are responsible to depend on the L<CBOR::XS> module if you
491use this functionality, as AnyEvent does not have a dependency itself. 533want to use this functionality, as AnyEvent does not have a dependency on
534it itself.
492 535
493=back 536=back
494 537
495=cut 538=cut
496 539
536 }); 579 });
537 580
538 } else { 581 } else {
539 if ($self->{on_connect_error}) { 582 if ($self->{on_connect_error}) {
540 $self->{on_connect_error}($self, "$!"); 583 $self->{on_connect_error}($self, "$!");
541 $self->destroy; 584 $self->destroy if $self;
542 } else { 585 } else {
543 $self->_error ($!, 1); 586 $self->_error ($!, 1);
544 } 587 }
545 } 588 }
546 }, 589 },
765 808
766sub rbuf_max { 809sub rbuf_max {
767 $_[0]{rbuf_max} = $_[1]; 810 $_[0]{rbuf_max} = $_[1];
768} 811}
769 812
770sub rbuf_max { 813sub wbuf_max {
771 $_[0]{wbuf_max} = $_[1]; 814 $_[0]{wbuf_max} = $_[1];
772} 815}
773 816
774############################################################################# 817#############################################################################
775 818
778=item $handle->rtimeout ($seconds) 821=item $handle->rtimeout ($seconds)
779 822
780=item $handle->wtimeout ($seconds) 823=item $handle->wtimeout ($seconds)
781 824
782Configures (or disables) the inactivity timeout. 825Configures (or disables) the inactivity timeout.
826
827The timeout will be checked instantly, so this method might destroy the
828handle before it returns.
783 829
784=item $handle->timeout_reset 830=item $handle->timeout_reset
785 831
786=item $handle->rtimeout_reset 832=item $handle->rtimeout_reset
787 833
871 917
872The write queue is very simple: you can add data to its end, and 918The write queue is very simple: you can add data to its end, and
873AnyEvent::Handle will automatically try to get rid of it for you. 919AnyEvent::Handle will automatically try to get rid of it for you.
874 920
875When data could be written and the write buffer is shorter then the low 921When data could be written and the write buffer is shorter then the low
876water mark, the C<on_drain> callback will be invoked. 922water mark, the C<on_drain> callback will be invoked once.
877 923
878=over 4 924=over 4
879 925
880=item $handle->on_drain ($cb) 926=item $handle->on_drain ($cb)
881 927
1023 1069
1024Encodes the given hash or array reference into a JSON object. Unless you 1070Encodes the given hash or array reference into a JSON object. Unless you
1025provide your own JSON object, this means it will be encoded to JSON text 1071provide your own JSON object, this means it will be encoded to JSON text
1026in UTF-8. 1072in UTF-8.
1027 1073
1074The default encoder might or might not handle every type of JSON value -
1075it might be limited to arrays and objects for security reasons. See the
1076C<json> constructor attribute for more details.
1077
1028JSON objects (and arrays) are self-delimiting, so you can write JSON at 1078JSON objects (and arrays) are self-delimiting, so if you only use arrays
1029one end of a handle and read them at the other end without using any 1079and hashes, you can write JSON at one end of a handle and read them at the
1030additional framing. 1080other end without using any additional framing.
1031 1081
1032The generated JSON text is guaranteed not to contain any newlines: While 1082The JSON text generated by the default encoder is guaranteed not to
1033this module doesn't need delimiters after or between JSON texts to be 1083contain any newlines: While this module doesn't need delimiters after or
1034able to read them, many other languages depend on that. 1084between JSON texts to be able to read them, many other languages depend on
1085them.
1035 1086
1036A simple RPC protocol that interoperates easily with others is to send 1087A simple RPC protocol that interoperates easily with other languages is
1037JSON arrays (or objects, although arrays are usually the better choice as 1088to send JSON arrays (or objects, although arrays are usually the better
1038they mimic how function argument passing works) and a newline after each 1089choice as they mimic how function argument passing works) and a newline
1039JSON text: 1090after each JSON text:
1040 1091
1041 $handle->push_write (json => ["method", "arg1", "arg2"]); # whatever 1092 $handle->push_write (json => ["method", "arg1", "arg2"]); # whatever
1042 $handle->push_write ("\012"); 1093 $handle->push_write ("\012");
1043 1094
1044An AnyEvent::Handle receiver would simply use the C<json> read type and 1095An AnyEvent::Handle receiver would simply use the C<json> read type and
1047 $handle->push_read (json => sub { my $array = $_[1]; ... }); 1098 $handle->push_read (json => sub { my $array = $_[1]; ... });
1048 1099
1049Other languages could read single lines terminated by a newline and pass 1100Other languages could read single lines terminated by a newline and pass
1050this line into their JSON decoder of choice. 1101this line into their JSON decoder of choice.
1051 1102
1103=item cbor => $perl_scalar
1104
1105Encodes the given scalar into a CBOR value. Unless you provide your own
1106L<CBOR::XS> object, this means it will be encoded to a CBOR string not
1107using any extensions, if possible.
1108
1109CBOR values are self-delimiting, so you can write CBOR at one end of
1110a handle and read them at the other end without using any additional
1111framing.
1112
1113A simple nd very very fast RPC protocol that interoperates with
1114other languages is to send CBOR and receive CBOR values (arrays are
1115recommended):
1116
1117 $handle->push_write (cbor => ["method", "arg1", "arg2"]); # whatever
1118
1119An AnyEvent::Handle receiver would simply use the C<cbor> read type:
1120
1121 $handle->push_read (cbor => sub { my $array = $_[1]; ... });
1122
1052=cut 1123=cut
1053 1124
1054sub json_coder() { 1125sub json_coder() {
1055 eval { require JSON::XS; JSON::XS->new->utf8 } 1126 eval { require JSON::XS; JSON::XS->new->utf8 }
1056 || do { require JSON; JSON->new->utf8 } 1127 || do { require JSON::PP; JSON::PP->new->utf8 }
1057} 1128}
1058 1129
1059register_write_type json => sub { 1130register_write_type json => sub {
1060 my ($self, $ref) = @_; 1131 my ($self, $ref) = @_;
1061 1132
1062 my $json = $self->{json} ||= json_coder; 1133 ($self->{json} ||= json_coder)
1063
1064 $json->encode ($ref) 1134 ->encode ($ref)
1135};
1136
1137sub cbor_coder() {
1138 require CBOR::XS;
1139 CBOR::XS->new
1140}
1141
1142register_write_type cbor => sub {
1143 my ($self, $scalar) = @_;
1144
1145 ($self->{cbor} ||= cbor_coder)
1146 ->encode ($scalar)
1065}; 1147};
1066 1148
1067=item storable => $reference 1149=item storable => $reference
1068 1150
1069Freezes the given reference using L<Storable> and writes it to the 1151Freezes the given reference using L<Storable> and writes it to the
1072=cut 1154=cut
1073 1155
1074register_write_type storable => sub { 1156register_write_type storable => sub {
1075 my ($self, $ref) = @_; 1157 my ($self, $ref) = @_;
1076 1158
1077 require Storable; 1159 require Storable unless $Storable::VERSION;
1078 1160
1079 pack "w/a*", Storable::nfreeze ($ref) 1161 pack "w/a*", Storable::nfreeze ($ref)
1080}; 1162};
1081 1163
1082=back 1164=back
1087before it was actually written. One way to do that is to replace your 1169before it was actually written. One way to do that is to replace your
1088C<on_drain> handler by a callback that shuts down the socket (and set 1170C<on_drain> handler by a callback that shuts down the socket (and set
1089C<low_water_mark> to C<0>). This method is a shorthand for just that, and 1171C<low_water_mark> to C<0>). This method is a shorthand for just that, and
1090replaces the C<on_drain> callback with: 1172replaces the C<on_drain> callback with:
1091 1173
1092 sub { shutdown $_[0]{fh}, 1 } # for push_shutdown 1174 sub { shutdown $_[0]{fh}, 1 }
1093 1175
1094This simply shuts down the write side and signals an EOF condition to the 1176This simply shuts down the write side and signals an EOF condition to the
1095the peer. 1177the peer.
1096 1178
1097You can rely on the normal read queue and C<on_eof> handling 1179You can rely on the normal read queue and C<on_eof> handling
1119 1201
1120Whenever the given C<type> is used, C<push_write> will the function with 1202Whenever the given C<type> is used, C<push_write> will the function with
1121the handle object and the remaining arguments. 1203the handle object and the remaining arguments.
1122 1204
1123The function is supposed to return a single octet string that will be 1205The function is supposed to return a single octet string that will be
1124appended to the write buffer, so you cna mentally treat this function as a 1206appended to the write buffer, so you can mentally treat this function as a
1125"arguments to on-the-wire-format" converter. 1207"arguments to on-the-wire-format" converter.
1126 1208
1127Example: implement a custom write type C<join> that joins the remaining 1209Example: implement a custom write type C<join> that joins the remaining
1128arguments using the first one. 1210arguments using the first one.
1129 1211
1423data. 1505data.
1424 1506
1425Example: read 2 bytes. 1507Example: read 2 bytes.
1426 1508
1427 $handle->push_read (chunk => 2, sub { 1509 $handle->push_read (chunk => 2, sub {
1428 warn "yay ", unpack "H*", $_[1]; 1510 say "yay " . unpack "H*", $_[1];
1429 }); 1511 });
1430 1512
1431=cut 1513=cut
1432 1514
1433register_read_type chunk => sub { 1515register_read_type chunk => sub {
1463 1545
1464register_read_type line => sub { 1546register_read_type line => sub {
1465 my ($self, $cb, $eol) = @_; 1547 my ($self, $cb, $eol) = @_;
1466 1548
1467 if (@_ < 3) { 1549 if (@_ < 3) {
1468 # this is more than twice as fast as the generic code below 1550 # this is faster then the generic code below
1469 sub { 1551 sub {
1470 $_[0]{rbuf} =~ s/^([^\015\012]*)(\015?\012)// or return; 1552 (my $pos = index $_[0]{rbuf}, "\012") >= 0
1553 or return;
1471 1554
1555 (my $str = substr $_[0]{rbuf}, 0, $pos + 1, "") =~ s/(\015?\012)\Z// or die;
1472 $cb->($_[0], $1, $2); 1556 $cb->($_[0], $str, "$1");
1473 1 1557 1
1474 } 1558 }
1475 } else { 1559 } else {
1476 $eol = quotemeta $eol unless ref $eol; 1560 $eol = quotemeta $eol unless ref $eol;
1477 $eol = qr|^(.*?)($eol)|s; 1561 $eol = qr|^(.*?)($eol)|s;
1478 1562
1479 sub { 1563 sub {
1480 $_[0]{rbuf} =~ s/$eol// or return; 1564 $_[0]{rbuf} =~ s/$eol// or return;
1481 1565
1482 $cb->($_[0], $1, $2); 1566 $cb->($_[0], "$1", "$2");
1483 1 1567 1
1484 } 1568 }
1485 } 1569 }
1486}; 1570};
1487 1571
1535 1619
1536 sub { 1620 sub {
1537 # accept 1621 # accept
1538 if ($$rbuf =~ $accept) { 1622 if ($$rbuf =~ $accept) {
1539 $data .= substr $$rbuf, 0, $+[0], ""; 1623 $data .= substr $$rbuf, 0, $+[0], "";
1540 $cb->($self, $data); 1624 $cb->($_[0], $data);
1541 return 1; 1625 return 1;
1542 } 1626 }
1543 1627
1544 # reject 1628 # reject
1545 if ($reject && $$rbuf =~ $reject) { 1629 if ($reject && $$rbuf =~ $reject) {
1546 $self->_error (Errno::EBADMSG); 1630 $_[0]->_error (Errno::EBADMSG);
1547 } 1631 }
1548 1632
1549 # skip 1633 # skip
1550 if ($skip && $$rbuf =~ $skip) { 1634 if ($skip && $$rbuf =~ $skip) {
1551 $data .= substr $$rbuf, 0, $+[0], ""; 1635 $data .= substr $$rbuf, 0, $+[0], "";
1567 my ($self, $cb) = @_; 1651 my ($self, $cb) = @_;
1568 1652
1569 sub { 1653 sub {
1570 unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) { 1654 unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
1571 if ($_[0]{rbuf} =~ /[^0-9]/) { 1655 if ($_[0]{rbuf} =~ /[^0-9]/) {
1572 $self->_error (Errno::EBADMSG); 1656 $_[0]->_error (Errno::EBADMSG);
1573 } 1657 }
1574 return; 1658 return;
1575 } 1659 }
1576 1660
1577 my $len = $1; 1661 my $len = $1;
1578 1662
1579 $self->unshift_read (chunk => $len, sub { 1663 $_[0]->unshift_read (chunk => $len, sub {
1580 my $string = $_[1]; 1664 my $string = $_[1];
1581 $_[0]->unshift_read (chunk => 1, sub { 1665 $_[0]->unshift_read (chunk => 1, sub {
1582 if ($_[1] eq ",") { 1666 if ($_[1] eq ",") {
1583 $cb->($_[0], $string); 1667 $cb->($_[0], $string);
1584 } else { 1668 } else {
1585 $self->_error (Errno::EBADMSG); 1669 $_[0]->_error (Errno::EBADMSG);
1586 } 1670 }
1587 }); 1671 });
1588 }); 1672 });
1589 1673
1590 1 1674 1
1640=item json => $cb->($handle, $hash_or_arrayref) 1724=item json => $cb->($handle, $hash_or_arrayref)
1641 1725
1642Reads a JSON object or array, decodes it and passes it to the 1726Reads a JSON object or array, decodes it and passes it to the
1643callback. When a parse error occurs, an C<EBADMSG> error will be raised. 1727callback. When a parse error occurs, an C<EBADMSG> error will be raised.
1644 1728
1645If a C<json> object was passed to the constructor, then that will be used 1729If a C<json> object was passed to the constructor, then that will be
1646for the final decode, otherwise it will create a JSON coder expecting UTF-8. 1730used for the final decode, otherwise it will create a L<JSON::XS> or
1731L<JSON::PP> coder object expecting UTF-8.
1647 1732
1648This read type uses the incremental parser available with JSON version 1733This read type uses the incremental parser available with JSON version
16492.09 (and JSON::XS version 2.2) and above. You have to provide a 17342.09 (and JSON::XS version 2.2) and above.
1650dependency on your own: this module will load the JSON module, but
1651AnyEvent does not depend on it itself.
1652 1735
1653Since JSON texts are fully self-delimiting, the C<json> read and write 1736Since JSON texts are fully self-delimiting, the C<json> read and write
1654types are an ideal simple RPC protocol: just exchange JSON datagrams. See 1737types are an ideal simple RPC protocol: just exchange JSON datagrams. See
1655the C<json> write type description, above, for an actual example. 1738the C<json> write type description, above, for an actual example.
1656 1739
1660 my ($self, $cb) = @_; 1743 my ($self, $cb) = @_;
1661 1744
1662 my $json = $self->{json} ||= json_coder; 1745 my $json = $self->{json} ||= json_coder;
1663 1746
1664 my $data; 1747 my $data;
1665 my $rbuf = \$self->{rbuf};
1666 1748
1667 sub { 1749 sub {
1668 my $ref = eval { $json->incr_parse ($self->{rbuf}) }; 1750 my $ref = eval { $json->incr_parse ($_[0]{rbuf}) };
1669 1751
1670 if ($ref) { 1752 if ($ref) {
1671 $self->{rbuf} = $json->incr_text; 1753 $_[0]{rbuf} = $json->incr_text;
1672 $json->incr_text = ""; 1754 $json->incr_text = "";
1673 $cb->($self, $ref); 1755 $cb->($_[0], $ref);
1674 1756
1675 1 1757 1
1676 } elsif ($@) { 1758 } elsif ($@) {
1677 # error case 1759 # error case
1678 $json->incr_skip; 1760 $json->incr_skip;
1679 1761
1680 $self->{rbuf} = $json->incr_text; 1762 $_[0]{rbuf} = $json->incr_text;
1681 $json->incr_text = ""; 1763 $json->incr_text = "";
1682 1764
1683 $self->_error (Errno::EBADMSG); 1765 $_[0]->_error (Errno::EBADMSG);
1684 1766
1685 () 1767 ()
1686 } else { 1768 } else {
1687 $self->{rbuf} = ""; 1769 $_[0]{rbuf} = "";
1688 1770
1771 ()
1772 }
1773 }
1774};
1775
1776=item cbor => $cb->($handle, $scalar)
1777
1778Reads a CBOR value, decodes it and passes it to the callback. When a parse
1779error occurs, an C<EBADMSG> error will be raised.
1780
1781If a L<CBOR::XS> object was passed to the constructor, then that will be
1782used for the final decode, otherwise it will create a CBOR coder without
1783enabling any options.
1784
1785You have to provide a dependency to L<CBOR::XS> on your own: this module
1786will load the L<CBOR::XS> module, but AnyEvent does not depend on it
1787itself.
1788
1789Since CBOR values are fully self-delimiting, the C<cbor> read and write
1790types are an ideal simple RPC protocol: just exchange CBOR datagrams. See
1791the C<cbor> write type description, above, for an actual example.
1792
1793=cut
1794
1795register_read_type cbor => sub {
1796 my ($self, $cb) = @_;
1797
1798 my $cbor = $self->{cbor} ||= cbor_coder;
1799
1800 my $data;
1801
1802 sub {
1803 my (@value) = eval { $cbor->incr_parse ($_[0]{rbuf}) };
1804
1805 if (@value) {
1806 $cb->($_[0], @value);
1807
1808 1
1809 } elsif ($@) {
1810 # error case
1811 $cbor->incr_reset;
1812
1813 $_[0]->_error (Errno::EBADMSG);
1814
1815 ()
1816 } else {
1689 () 1817 ()
1690 } 1818 }
1691 } 1819 }
1692}; 1820};
1693 1821
1702=cut 1830=cut
1703 1831
1704register_read_type storable => sub { 1832register_read_type storable => sub {
1705 my ($self, $cb) = @_; 1833 my ($self, $cb) = @_;
1706 1834
1707 require Storable; 1835 require Storable unless $Storable::VERSION;
1708 1836
1709 sub { 1837 sub {
1710 # when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method 1838 # when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
1711 defined (my $len = eval { unpack "w", $_[0]{rbuf} }) 1839 defined (my $len = eval { unpack "w", $_[0]{rbuf} })
1712 or return; 1840 or return;
1715 1843
1716 # bypass unshift if we already have the remaining chunk 1844 # bypass unshift if we already have the remaining chunk
1717 if ($format + $len <= length $_[0]{rbuf}) { 1845 if ($format + $len <= length $_[0]{rbuf}) {
1718 my $data = substr $_[0]{rbuf}, $format, $len; 1846 my $data = substr $_[0]{rbuf}, $format, $len;
1719 substr $_[0]{rbuf}, 0, $format + $len, ""; 1847 substr $_[0]{rbuf}, 0, $format + $len, "";
1848
1720 $cb->($_[0], Storable::thaw ($data)); 1849 eval { $cb->($_[0], Storable::thaw ($data)); 1 }
1850 or return $_[0]->_error (Errno::EBADMSG);
1721 } else { 1851 } else {
1722 # remove prefix 1852 # remove prefix
1723 substr $_[0]{rbuf}, 0, $format, ""; 1853 substr $_[0]{rbuf}, 0, $format, "";
1724 1854
1725 # read remaining chunk 1855 # read remaining chunk
1726 $_[0]->unshift_read (chunk => $len, sub { 1856 $_[0]->unshift_read (chunk => $len, sub {
1727 if (my $ref = eval { Storable::thaw ($_[1]) }) { 1857 eval { $cb->($_[0], Storable::thaw ($_[1])); 1 }
1728 $cb->($_[0], $ref);
1729 } else {
1730 $self->_error (Errno::EBADMSG); 1858 or $_[0]->_error (Errno::EBADMSG);
1731 }
1732 }); 1859 });
1733 } 1860 }
1734 1861
1735 1 1862 1
1736 } 1863 }
1864};
1865
1866=item tls_detect => $cb->($handle, $detect, $major, $minor)
1867
1868Checks the input stream for a valid SSL or TLS handshake TLSPaintext
1869record without consuming anything. Only SSL version 3 or higher
1870is handled, up to the fictituous protocol 4.x (but both SSL3+ and
1871SSL2-compatible framing is supported).
1872
1873If it detects that the input data is likely TLS, it calls the callback
1874with a true value for C<$detect> and the (on-wire) TLS version as second
1875and third argument (C<$major> is C<3>, and C<$minor> is 0..3 for SSL
18763.0, TLS 1.0, 1.1 and 1.2, respectively). If it detects the input to
1877be definitely not TLS, it calls the callback with a false value for
1878C<$detect>.
1879
1880The callback could use this information to decide whether or not to start
1881TLS negotiation.
1882
1883In all cases the data read so far is passed to the following read
1884handlers.
1885
1886Usually you want to use the C<tls_autostart> read type instead.
1887
1888If you want to design a protocol that works in the presence of TLS
1889dtection, make sure that any non-TLS data doesn't start with the octet 22
1890(ASCII SYN, 16 hex) or 128-255 (i.e. highest bit set). The checks this
1891read type does are a bit more strict, but might losen in the future to
1892accomodate protocol changes.
1893
1894This read type does not rely on L<AnyEvent::TLS> (and thus, not on
1895L<Net::SSLeay>).
1896
1897=item tls_autostart => $tls[, $tls_ctx]
1898
1899Tries to detect a valid SSL or TLS handshake. If one is detected, it tries
1900to start tls by calling C<starttls> with the given arguments.
1901
1902In practise, C<$tls> must be C<accept>, or a Net::SSLeay context that has
1903been configured to accept, as servers do not normally send a handshake on
1904their own and ths cannot be detected in this way.
1905
1906See C<tls_detect> above for more details.
1907
1908Example: give the client a chance to start TLS before accepting a text
1909line.
1910
1911 $hdl->push_read (tls_detect => "accept");
1912 $hdl->push_read (line => sub {
1913 print "received ", ($_[0]{tls} ? "encrypted" : "cleartext"), " <$_[1]>\n";
1914 });
1915
1916=cut
1917
1918register_read_type tls_detect => sub {
1919 my ($self, $cb) = @_;
1920
1921 sub {
1922 # this regex matches a full or partial tls record
1923 if (
1924 # ssl3+: type(22=handshake) major(=3) minor(any) length_hi
1925 $self->{rbuf} =~ /^(?:\z| \x16 (\z| [\x03\x04] (?:\z| . (?:\z| [\x00-\x40] ))))/xs
1926 # ssl2 comapatible: len_hi len_lo type(1) major minor dummy(forlength)
1927 or $self->{rbuf} =~ /^(?:\z| [\x80-\xff] (?:\z| . (?:\z| \x01 (\z| [\x03\x04] (?:\z| . (?:\z| . ))))))/xs
1928 ) {
1929 return if 3 != length $1; # partial match, can't decide yet
1930
1931 # full match, valid TLS record
1932 my ($major, $minor) = unpack "CC", $1;
1933 $cb->($self, "accept", $major + $minor * 0.1);
1934 } else {
1935 # mismatch == guaranteed not TLS
1936 $cb->($self, undef);
1937 }
1938
1939 1
1940 }
1941};
1942
1943register_read_type tls_autostart => sub {
1944 my ($self, @tls) = @_;
1945
1946 $RH{tls_detect}($self, sub {
1947 return unless $_[1];
1948 $_[0]->starttls (@tls);
1949 })
1737}; 1950};
1738 1951
1739=back 1952=back
1740 1953
1741=item custom read types - Package::anyevent_read_type $handle, $cb, @args 1954=item custom read types - Package::anyevent_read_type $handle, $cb, @args
1773Note that AnyEvent::Handle will automatically C<start_read> for you when 1986Note that AnyEvent::Handle will automatically C<start_read> for you when
1774you change the C<on_read> callback or push/unshift a read callback, and it 1987you change the C<on_read> callback or push/unshift a read callback, and it
1775will automatically C<stop_read> for you when neither C<on_read> is set nor 1988will automatically C<stop_read> for you when neither C<on_read> is set nor
1776there are any read requests in the queue. 1989there are any read requests in the queue.
1777 1990
1778These methods will have no effect when in TLS mode (as TLS doesn't support 1991In older versions of this module (<= 5.3), these methods had no effect,
1779half-duplex connections). 1992as TLS does not support half-duplex connections. In current versions they
1993work as expected, as this behaviour is required to avoid certain resource
1994attacks, where the program would be forced to read (and buffer) arbitrary
1995amounts of data before being able to send some data. The drawback is that
1996some readings of the the SSL/TLS specifications basically require this
1997attack to be working, as SSL/TLS implementations might stall sending data
1998during a rehandshake.
1999
2000As a guideline, during the initial handshake, you should not stop reading,
2001and as a client, it might cause problems, depending on your application.
1780 2002
1781=cut 2003=cut
1782 2004
1783sub stop_read { 2005sub stop_read {
1784 my ($self) = @_; 2006 my ($self) = @_;
1785 2007
1786 delete $self->{_rw} unless $self->{tls}; 2008 delete $self->{_rw};
1787} 2009}
1788 2010
1789sub start_read { 2011sub start_read {
1790 my ($self) = @_; 2012 my ($self) = @_;
1791 2013
1832 my ($self, $err) = @_; 2054 my ($self, $err) = @_;
1833 2055
1834 return $self->_error ($!, 1) 2056 return $self->_error ($!, 1)
1835 if $err == Net::SSLeay::ERROR_SYSCALL (); 2057 if $err == Net::SSLeay::ERROR_SYSCALL ();
1836 2058
1837 my $err =Net::SSLeay::ERR_error_string (Net::SSLeay::ERR_get_error ()); 2059 my $err = Net::SSLeay::ERR_error_string (Net::SSLeay::ERR_get_error ());
1838 2060
1839 # reduce error string to look less scary 2061 # reduce error string to look less scary
1840 $err =~ s/^error:[0-9a-fA-F]{8}:[^:]+:([^:]+):/\L$1: /; 2062 $err =~ s/^error:[0-9a-fA-F]{8}:[^:]+:([^:]+):/\L$1: /;
1841 2063
1842 if ($self->{_on_starttls}) { 2064 if ($self->{_on_starttls}) {
1856sub _dotls { 2078sub _dotls {
1857 my ($self) = @_; 2079 my ($self) = @_;
1858 2080
1859 my $tmp; 2081 my $tmp;
1860 2082
1861 if (length $self->{_tls_wbuf}) { 2083 while (length $self->{_tls_wbuf}) {
1862 while (($tmp = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) { 2084 if (($tmp = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) <= 0) {
1863 substr $self->{_tls_wbuf}, 0, $tmp, ""; 2085 $tmp = Net::SSLeay::get_error ($self->{tls}, $tmp);
2086
2087 return $self->_tls_error ($tmp)
2088 if $tmp != $ERROR_WANT_READ
2089 && ($tmp != $ERROR_SYSCALL || $!);
2090
2091 last;
1864 } 2092 }
1865 2093
1866 $tmp = Net::SSLeay::get_error ($self->{tls}, $tmp); 2094 substr $self->{_tls_wbuf}, 0, $tmp, "";
1867 return $self->_tls_error ($tmp)
1868 if $tmp != $ERROR_WANT_READ
1869 && ($tmp != $ERROR_SYSCALL || $!);
1870 } 2095 }
1871 2096
1872 while (defined ($tmp = Net::SSLeay::read ($self->{tls}))) { 2097 while (defined ($tmp = Net::SSLeay::read ($self->{tls}))) {
1873 unless (length $tmp) { 2098 unless (length $tmp) {
1874 $self->{_on_starttls} 2099 $self->{_on_starttls}
1888 $self->{_tls_rbuf} .= $tmp; 2113 $self->{_tls_rbuf} .= $tmp;
1889 $self->_drain_rbuf; 2114 $self->_drain_rbuf;
1890 $self->{tls} or return; # tls session might have gone away in callback 2115 $self->{tls} or return; # tls session might have gone away in callback
1891 } 2116 }
1892 2117
1893 $tmp = Net::SSLeay::get_error ($self->{tls}, -1); 2118 $tmp = Net::SSLeay::get_error ($self->{tls}, -1); # -1 is not neccessarily correct, but Net::SSLeay doesn't tell us
1894 return $self->_tls_error ($tmp) 2119 return $self->_tls_error ($tmp)
1895 if $tmp != $ERROR_WANT_READ 2120 if $tmp != $ERROR_WANT_READ
1896 && ($tmp != $ERROR_SYSCALL || $!); 2121 && ($tmp != $ERROR_SYSCALL || $!);
1897 2122
1898 while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) { 2123 while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) {
1908 2133
1909=item $handle->starttls ($tls[, $tls_ctx]) 2134=item $handle->starttls ($tls[, $tls_ctx])
1910 2135
1911Instead of starting TLS negotiation immediately when the AnyEvent::Handle 2136Instead of starting TLS negotiation immediately when the AnyEvent::Handle
1912object is created, you can also do that at a later time by calling 2137object is created, you can also do that at a later time by calling
1913C<starttls>. 2138C<starttls>. See the C<tls> constructor argument for general info.
1914 2139
1915Starting TLS is currently an asynchronous operation - when you push some 2140Starting TLS is currently an asynchronous operation - when you push some
1916write data and then call C<< ->starttls >> then TLS negotiation will start 2141write data and then call C<< ->starttls >> then TLS negotiation will start
1917immediately, after which the queued write data is then sent. 2142immediately, after which the queued write data is then sent. This might
2143change in future versions, so best make sure you have no outstanding write
2144data when calling this method.
1918 2145
1919The first argument is the same as the C<tls> constructor argument (either 2146The first argument is the same as the C<tls> constructor argument (either
1920C<"connect">, C<"accept"> or an existing Net::SSLeay object). 2147C<"connect">, C<"accept"> or an existing Net::SSLeay object).
1921 2148
1922The second argument is the optional C<AnyEvent::TLS> object that is used 2149The second argument is the optional C<AnyEvent::TLS> object that is used
1944 my ($self, $tls, $ctx) = @_; 2171 my ($self, $tls, $ctx) = @_;
1945 2172
1946 Carp::croak "It is an error to call starttls on an AnyEvent::Handle object while TLS is already active, caught" 2173 Carp::croak "It is an error to call starttls on an AnyEvent::Handle object while TLS is already active, caught"
1947 if $self->{tls}; 2174 if $self->{tls};
1948 2175
2176 unless (defined $AnyEvent::TLS::VERSION) {
2177 eval {
2178 require Net::SSLeay;
2179 require AnyEvent::TLS;
2180 1
2181 } or return $self->_error (Errno::EPROTO, 1, "TLS support not available on this system");
2182 }
2183
1949 $self->{tls} = $tls; 2184 $self->{tls} = $tls;
1950 $self->{tls_ctx} = $ctx if @_ > 2; 2185 $self->{tls_ctx} = $ctx if @_ > 2;
1951 2186
1952 return unless $self->{fh}; 2187 return unless $self->{fh};
1953 2188
1954 require Net::SSLeay;
1955
1956 $ERROR_SYSCALL = Net::SSLeay::ERROR_SYSCALL (); 2189 $ERROR_SYSCALL = Net::SSLeay::ERROR_SYSCALL ();
1957 $ERROR_WANT_READ = Net::SSLeay::ERROR_WANT_READ (); 2190 $ERROR_WANT_READ = Net::SSLeay::ERROR_WANT_READ ();
1958 2191
1959 $tls = delete $self->{tls}; 2192 $tls = delete $self->{tls};
1960 $ctx = $self->{tls_ctx}; 2193 $ctx = $self->{tls_ctx};
1961 2194
1962 local $Carp::CarpLevel = 1; # skip ourselves when creating a new context or session 2195 local $Carp::CarpLevel = 1; # skip ourselves when creating a new context or session
1963 2196
1964 if ("HASH" eq ref $ctx) { 2197 if ("HASH" eq ref $ctx) {
1965 require AnyEvent::TLS;
1966
1967 if ($ctx->{cache}) { 2198 if ($ctx->{cache}) {
1968 my $key = $ctx+0; 2199 my $key = $ctx+0;
1969 $ctx = $TLS_CACHE{$key} ||= new AnyEvent::TLS %$ctx; 2200 $ctx = $TLS_CACHE{$key} ||= new AnyEvent::TLS %$ctx;
1970 } else { 2201 } else {
1971 $ctx = new AnyEvent::TLS %$ctx; 2202 $ctx = new AnyEvent::TLS %$ctx;
1993 Net::SSLeay::CTX_set_mode ($tls, 1|2); 2224 Net::SSLeay::CTX_set_mode ($tls, 1|2);
1994 2225
1995 $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); 2226 $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1996 $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); 2227 $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1997 2228
1998 Net::SSLeay::BIO_write ($self->{_rbio}, delete $self->{rbuf}); 2229 Net::SSLeay::BIO_write ($self->{_rbio}, $self->{rbuf});
2230 $self->{rbuf} = "";
1999 2231
2000 Net::SSLeay::set_bio ($tls, $self->{_rbio}, $self->{_wbio}); 2232 Net::SSLeay::set_bio ($tls, $self->{_rbio}, $self->{_wbio});
2001 2233
2002 $self->{_on_starttls} = sub { $_[0]{on_starttls}(@_) } 2234 $self->{_on_starttls} = sub { $_[0]{on_starttls}(@_) }
2003 if $self->{on_starttls}; 2235 if $self->{on_starttls};
2040 $self->{tls_ctx}->_put_session (delete $self->{tls}) 2272 $self->{tls_ctx}->_put_session (delete $self->{tls})
2041 if $self->{tls} > 0; 2273 if $self->{tls} > 0;
2042 2274
2043 delete @$self{qw(_rbio _wbio _tls_wbuf _on_starttls)}; 2275 delete @$self{qw(_rbio _wbio _tls_wbuf _on_starttls)};
2044} 2276}
2277
2278=item $handle->resettls
2279
2280This rarely-used method simply resets and TLS state on the handle, usually
2281causing data loss.
2282
2283One case where it may be useful is when you want to skip over the data in
2284the stream but you are not interested in interpreting it, so data loss is
2285no concern.
2286
2287=cut
2288
2289*resettls = \&_freetls;
2045 2290
2046sub DESTROY { 2291sub DESTROY {
2047 my ($self) = @_; 2292 my ($self) = @_;
2048 2293
2049 &_freetls; 2294 &_freetls;
2172Probably because your C<on_error> callback is being called instead: When 2417Probably because your C<on_error> callback is being called instead: When
2173you have outstanding requests in your read queue, then an EOF is 2418you have outstanding requests in your read queue, then an EOF is
2174considered an error as you clearly expected some data. 2419considered an error as you clearly expected some data.
2175 2420
2176To avoid this, make sure you have an empty read queue whenever your handle 2421To avoid this, make sure you have an empty read queue whenever your handle
2177is supposed to be "idle" (i.e. connection closes are O.K.). You cna set 2422is supposed to be "idle" (i.e. connection closes are O.K.). You can set
2178an C<on_read> handler that simply pushes the first read requests in the 2423an C<on_read> handler that simply pushes the first read requests in the
2179queue. 2424queue.
2180 2425
2181See also the next question, which explains this in a bit more detail. 2426See also the next question, which explains this in a bit more detail.
2182 2427
2190handles requests until the server gets some QUIT command, causing it to 2435handles requests until the server gets some QUIT command, causing it to
2191close the connection first (highly desirable for a busy TCP server). A 2436close the connection first (highly desirable for a busy TCP server). A
2192client dropping the connection is an error, which means this variant can 2437client dropping the connection is an error, which means this variant can
2193detect an unexpected detection close. 2438detect an unexpected detection close.
2194 2439
2195To handle this case, always make sure you have a on-empty read queue, by 2440To handle this case, always make sure you have a non-empty read queue, by
2196pushing the "read request start" handler on it: 2441pushing the "read request start" handler on it:
2197 2442
2198 # we assume a request starts with a single line 2443 # we assume a request starts with a single line
2199 my @start_request; @start_request = (line => sub { 2444 my @start_request; @start_request = (line => sub {
2200 my ($hdl, $line) = @_; 2445 my ($hdl, $line) = @_;
2213some data and raises the C<EPIPE> error when the connction is dropped 2458some data and raises the C<EPIPE> error when the connction is dropped
2214unexpectedly. 2459unexpectedly.
2215 2460
2216The second variant is a protocol where the client can drop the connection 2461The second variant is a protocol where the client can drop the connection
2217at any time. For TCP, this means that the server machine may run out of 2462at any time. For TCP, this means that the server machine may run out of
2218sockets easier, and in general, it means you cnanot distinguish a protocl 2463sockets easier, and in general, it means you cannot distinguish a protocl
2219failure/client crash from a normal connection close. Nevertheless, these 2464failure/client crash from a normal connection close. Nevertheless, these
2220kinds of protocols are common (and sometimes even the best solution to the 2465kinds of protocols are common (and sometimes even the best solution to the
2221problem). 2466problem).
2222 2467
2223Having an outstanding read request at all times is possible if you ignore 2468Having an outstanding read request at all times is possible if you ignore
2275 $handle->on_eof (undef); 2520 $handle->on_eof (undef);
2276 $handle->on_error (sub { 2521 $handle->on_error (sub {
2277 my $data = delete $_[0]{rbuf}; 2522 my $data = delete $_[0]{rbuf};
2278 }); 2523 });
2279 2524
2525Note that this example removes the C<rbuf> member from the handle object,
2526which is not normally allowed by the API. It is expressly permitted in
2527this case only, as the handle object needs to be destroyed afterwards.
2528
2280The reason to use C<on_error> is that TCP connections, due to latencies 2529The reason to use C<on_error> is that TCP connections, due to latencies
2281and packets loss, might get closed quite violently with an error, when in 2530and packets loss, might get closed quite violently with an error, when in
2282fact all data has been received. 2531fact all data has been received.
2283 2532
2284It is usually better to use acknowledgements when transferring data, 2533It is usually better to use acknowledgements when transferring data,
2294C<low_water_mark> this will be called precisely when all data has been 2543C<low_water_mark> this will be called precisely when all data has been
2295written to the socket: 2544written to the socket:
2296 2545
2297 $handle->push_write (...); 2546 $handle->push_write (...);
2298 $handle->on_drain (sub { 2547 $handle->on_drain (sub {
2299 warn "all data submitted to the kernel\n"; 2548 AE::log debug => "All data submitted to the kernel.";
2300 undef $handle; 2549 undef $handle;
2301 }); 2550 });
2302 2551
2303If you just want to queue some data and then signal EOF to the other side, 2552If you just want to queue some data and then signal EOF to the other side,
2304consider using C<< ->push_shutdown >> instead. 2553consider using C<< ->push_shutdown >> instead.
2388When you have intermediate CA certificates that your clients might not 2637When you have intermediate CA certificates that your clients might not
2389know about, just append them to the C<cert_file>. 2638know about, just append them to the C<cert_file>.
2390 2639
2391=back 2640=back
2392 2641
2393
2394=head1 SUBCLASSING AnyEvent::Handle 2642=head1 SUBCLASSING AnyEvent::Handle
2395 2643
2396In many cases, you might want to subclass AnyEvent::Handle. 2644In many cases, you might want to subclass AnyEvent::Handle.
2397 2645
2398To make this easier, a given version of AnyEvent::Handle uses these 2646To make this easier, a given version of AnyEvent::Handle uses these
2424 2672
2425Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>. 2673Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>.
2426 2674
2427=cut 2675=cut
2428 2676
24291; # End of AnyEvent::Handle 26771
2678

Diff Legend

Removed lines
+ Added lines
< Changed lines
> Changed lines