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Comparing AnyEvent/lib/AnyEvent/Handle.pm (file contents):
Revision 1.203 by root, Sat Oct 16 03:22:10 2010 UTC vs.
Revision 1.237 by root, Tue Jul 30 23:14:32 2013 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, $message)
144 150
159 165
160Some errors are fatal (which is indicated by C<$fatal> being true). On 166Some errors are fatal (which is indicated by C<$fatal> being true). On
161fatal errors the handle object will be destroyed (by a call to C<< -> 167fatal errors the handle object will be destroyed (by a call to C<< ->
162destroy >>) after invoking the error callback (which means you are free to 168destroy >>) after invoking the error callback (which means you are free to
163examine the handle object). Examples of fatal errors are an EOF condition 169examine the handle object). Examples of fatal errors are an EOF condition
164with active (but unsatisifable) read watchers (C<EPIPE>) or I/O errors. In 170with active (but unsatisfiable) read watchers (C<EPIPE>) or I/O errors. In
165cases where the other side can close the connection at will, it is 171cases where the other side can close the connection at will, it is
166often easiest to not report C<EPIPE> errors in this callback. 172often easiest to not report C<EPIPE> errors in this callback.
167 173
168AnyEvent::Handle tries to find an appropriate error code for you to check 174AnyEvent::Handle tries to find an appropriate error code for you to check
169against, but in some cases (TLS errors), this does not work well. It is 175against, but in some cases (TLS errors), this does not work well.
170recommended to always output the C<$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
502 $self->{connect}[0], 537 $self->{connect}[0],
503 $self->{connect}[1], 538 $self->{connect}[1],
504 sub { 539 sub {
505 my ($fh, $host, $port, $retry) = @_; 540 my ($fh, $host, $port, $retry) = @_;
506 541
542 delete $self->{_connect}; # no longer needed
543
507 if ($fh) { 544 if ($fh) {
508 $self->{fh} = $fh; 545 $self->{fh} = $fh;
509 546
510 delete $self->{_skip_drain_rbuf}; 547 delete $self->{_skip_drain_rbuf};
511 $self->_start; 548 $self->_start;
518 }); 555 });
519 556
520 } else { 557 } else {
521 if ($self->{on_connect_error}) { 558 if ($self->{on_connect_error}) {
522 $self->{on_connect_error}($self, "$!"); 559 $self->{on_connect_error}($self, "$!");
523 $self->destroy; 560 $self->destroy if $self;
524 } else { 561 } else {
525 $self->_error ($!, 1); 562 $self->_error ($!, 1);
526 } 563 }
527 } 564 }
528 }, 565 },
529 sub { 566 sub {
530 local $self->{fh} = $_[0]; 567 local $self->{fh} = $_[0];
531 568
532 $self->{on_prepare} 569 $self->{on_prepare}
533 ? $self->{on_prepare}->($self) 570 ? $self->{on_prepare}->($self)
534 : () 571 : ()
535 } 572 }
536 ); 573 );
537 } 574 }
538 575
737 774
738=item $handle->rbuf_max ($max_octets) 775=item $handle->rbuf_max ($max_octets)
739 776
740Configures the C<rbuf_max> setting (C<undef> disables it). 777Configures the C<rbuf_max> setting (C<undef> disables it).
741 778
779=item $handle->wbuf_max ($max_octets)
780
781Configures the C<wbuf_max> setting (C<undef> disables it).
782
742=cut 783=cut
743 784
744sub rbuf_max { 785sub rbuf_max {
745 $_[0]{rbuf_max} = $_[1]; 786 $_[0]{rbuf_max} = $_[1];
746} 787}
747 788
789sub wbuf_max {
790 $_[0]{wbuf_max} = $_[1];
791}
792
748############################################################################# 793#############################################################################
749 794
750=item $handle->timeout ($seconds) 795=item $handle->timeout ($seconds)
751 796
752=item $handle->rtimeout ($seconds) 797=item $handle->rtimeout ($seconds)
753 798
754=item $handle->wtimeout ($seconds) 799=item $handle->wtimeout ($seconds)
755 800
756Configures (or disables) the inactivity timeout. 801Configures (or disables) the inactivity timeout.
802
803The timeout will be checked instantly, so this method might destroy the
804handle before it returns.
757 805
758=item $handle->timeout_reset 806=item $handle->timeout_reset
759 807
760=item $handle->rtimeout_reset 808=item $handle->rtimeout_reset
761 809
845 893
846The write queue is very simple: you can add data to its end, and 894The write queue is very simple: you can add data to its end, and
847AnyEvent::Handle will automatically try to get rid of it for you. 895AnyEvent::Handle will automatically try to get rid of it for you.
848 896
849When data could be written and the write buffer is shorter then the low 897When data could be written and the write buffer is shorter then the low
850water mark, the C<on_drain> callback will be invoked. 898water mark, the C<on_drain> callback will be invoked once.
851 899
852=over 4 900=over 4
853 901
854=item $handle->on_drain ($cb) 902=item $handle->on_drain ($cb)
855 903
870 if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf}); 918 if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf});
871} 919}
872 920
873=item $handle->push_write ($data) 921=item $handle->push_write ($data)
874 922
875Queues the given scalar to be written. You can push as much data as you 923Queues the given scalar to be written. You can push as much data as
876want (only limited by the available memory), as C<AnyEvent::Handle> 924you want (only limited by the available memory and C<wbuf_max>), as
877buffers it independently of the kernel. 925C<AnyEvent::Handle> buffers it independently of the kernel.
878 926
879This method may invoke callbacks (and therefore the handle might be 927This method may invoke callbacks (and therefore the handle might be
880destroyed after it returns). 928destroyed after it returns).
881 929
882=cut 930=cut
910 $cb->() unless $self->{autocork}; 958 $cb->() unless $self->{autocork};
911 959
912 # if still data left in wbuf, we need to poll 960 # if still data left in wbuf, we need to poll
913 $self->{_ww} = AE::io $self->{fh}, 1, $cb 961 $self->{_ww} = AE::io $self->{fh}, 1, $cb
914 if length $self->{wbuf}; 962 if length $self->{wbuf};
963
964 if (
965 defined $self->{wbuf_max}
966 && $self->{wbuf_max} < length $self->{wbuf}
967 ) {
968 $self->_error (Errno::ENOSPC, 1), return;
969 }
915 }; 970 };
916} 971}
917 972
918our %WH; 973our %WH;
919 974
1039=cut 1094=cut
1040 1095
1041register_write_type storable => sub { 1096register_write_type storable => sub {
1042 my ($self, $ref) = @_; 1097 my ($self, $ref) = @_;
1043 1098
1044 require Storable; 1099 require Storable unless $Storable::VERSION;
1045 1100
1046 pack "w/a*", Storable::nfreeze ($ref) 1101 pack "w/a*", Storable::nfreeze ($ref)
1047}; 1102};
1048 1103
1049=back 1104=back
1054before it was actually written. One way to do that is to replace your 1109before it was actually written. One way to do that is to replace your
1055C<on_drain> handler by a callback that shuts down the socket (and set 1110C<on_drain> handler by a callback that shuts down the socket (and set
1056C<low_water_mark> to C<0>). This method is a shorthand for just that, and 1111C<low_water_mark> to C<0>). This method is a shorthand for just that, and
1057replaces the C<on_drain> callback with: 1112replaces the C<on_drain> callback with:
1058 1113
1059 sub { shutdown $_[0]{fh}, 1 } # for push_shutdown 1114 sub { shutdown $_[0]{fh}, 1 }
1060 1115
1061This simply shuts down the write side and signals an EOF condition to the 1116This simply shuts down the write side and signals an EOF condition to the
1062the peer. 1117the peer.
1063 1118
1064You can rely on the normal read queue and C<on_eof> handling 1119You can rely on the normal read queue and C<on_eof> handling
1086 1141
1087Whenever the given C<type> is used, C<push_write> will the function with 1142Whenever the given C<type> is used, C<push_write> will the function with
1088the handle object and the remaining arguments. 1143the handle object and the remaining arguments.
1089 1144
1090The function is supposed to return a single octet string that will be 1145The function is supposed to return a single octet string that will be
1091appended to the write buffer, so you cna mentally treat this function as a 1146appended to the write buffer, so you can mentally treat this function as a
1092"arguments to on-the-wire-format" converter. 1147"arguments to on-the-wire-format" converter.
1093 1148
1094Example: implement a custom write type C<join> that joins the remaining 1149Example: implement a custom write type C<join> that joins the remaining
1095arguments using the first one. 1150arguments using the first one.
1096 1151
1390data. 1445data.
1391 1446
1392Example: read 2 bytes. 1447Example: read 2 bytes.
1393 1448
1394 $handle->push_read (chunk => 2, sub { 1449 $handle->push_read (chunk => 2, sub {
1395 warn "yay ", unpack "H*", $_[1]; 1450 say "yay " . unpack "H*", $_[1];
1396 }); 1451 });
1397 1452
1398=cut 1453=cut
1399 1454
1400register_read_type chunk => sub { 1455register_read_type chunk => sub {
1430 1485
1431register_read_type line => sub { 1486register_read_type line => sub {
1432 my ($self, $cb, $eol) = @_; 1487 my ($self, $cb, $eol) = @_;
1433 1488
1434 if (@_ < 3) { 1489 if (@_ < 3) {
1435 # this is more than twice as fast as the generic code below 1490 # this is faster then the generic code below
1436 sub { 1491 sub {
1437 $_[0]{rbuf} =~ s/^([^\015\012]*)(\015?\012)// or return; 1492 (my $pos = index $_[0]{rbuf}, "\012") >= 0
1493 or return;
1438 1494
1495 (my $str = substr $_[0]{rbuf}, 0, $pos + 1, "") =~ s/(\015?\012)\Z// or die;
1439 $cb->($_[0], $1, $2); 1496 $cb->($_[0], $str, "$1");
1440 1 1497 1
1441 } 1498 }
1442 } else { 1499 } else {
1443 $eol = quotemeta $eol unless ref $eol; 1500 $eol = quotemeta $eol unless ref $eol;
1444 $eol = qr|^(.*?)($eol)|s; 1501 $eol = qr|^(.*?)($eol)|s;
1445 1502
1446 sub { 1503 sub {
1447 $_[0]{rbuf} =~ s/$eol// or return; 1504 $_[0]{rbuf} =~ s/$eol// or return;
1448 1505
1449 $cb->($_[0], $1, $2); 1506 $cb->($_[0], "$1", "$2");
1450 1 1507 1
1451 } 1508 }
1452 } 1509 }
1453}; 1510};
1454 1511
1502 1559
1503 sub { 1560 sub {
1504 # accept 1561 # accept
1505 if ($$rbuf =~ $accept) { 1562 if ($$rbuf =~ $accept) {
1506 $data .= substr $$rbuf, 0, $+[0], ""; 1563 $data .= substr $$rbuf, 0, $+[0], "";
1507 $cb->($self, $data); 1564 $cb->($_[0], $data);
1508 return 1; 1565 return 1;
1509 } 1566 }
1510 1567
1511 # reject 1568 # reject
1512 if ($reject && $$rbuf =~ $reject) { 1569 if ($reject && $$rbuf =~ $reject) {
1513 $self->_error (Errno::EBADMSG); 1570 $_[0]->_error (Errno::EBADMSG);
1514 } 1571 }
1515 1572
1516 # skip 1573 # skip
1517 if ($skip && $$rbuf =~ $skip) { 1574 if ($skip && $$rbuf =~ $skip) {
1518 $data .= substr $$rbuf, 0, $+[0], ""; 1575 $data .= substr $$rbuf, 0, $+[0], "";
1534 my ($self, $cb) = @_; 1591 my ($self, $cb) = @_;
1535 1592
1536 sub { 1593 sub {
1537 unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) { 1594 unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
1538 if ($_[0]{rbuf} =~ /[^0-9]/) { 1595 if ($_[0]{rbuf} =~ /[^0-9]/) {
1539 $self->_error (Errno::EBADMSG); 1596 $_[0]->_error (Errno::EBADMSG);
1540 } 1597 }
1541 return; 1598 return;
1542 } 1599 }
1543 1600
1544 my $len = $1; 1601 my $len = $1;
1545 1602
1546 $self->unshift_read (chunk => $len, sub { 1603 $_[0]->unshift_read (chunk => $len, sub {
1547 my $string = $_[1]; 1604 my $string = $_[1];
1548 $_[0]->unshift_read (chunk => 1, sub { 1605 $_[0]->unshift_read (chunk => 1, sub {
1549 if ($_[1] eq ",") { 1606 if ($_[1] eq ",") {
1550 $cb->($_[0], $string); 1607 $cb->($_[0], $string);
1551 } else { 1608 } else {
1552 $self->_error (Errno::EBADMSG); 1609 $_[0]->_error (Errno::EBADMSG);
1553 } 1610 }
1554 }); 1611 });
1555 }); 1612 });
1556 1613
1557 1 1614 1
1630 1687
1631 my $data; 1688 my $data;
1632 my $rbuf = \$self->{rbuf}; 1689 my $rbuf = \$self->{rbuf};
1633 1690
1634 sub { 1691 sub {
1635 my $ref = eval { $json->incr_parse ($self->{rbuf}) }; 1692 my $ref = eval { $json->incr_parse ($_[0]{rbuf}) };
1636 1693
1637 if ($ref) { 1694 if ($ref) {
1638 $self->{rbuf} = $json->incr_text; 1695 $_[0]{rbuf} = $json->incr_text;
1639 $json->incr_text = ""; 1696 $json->incr_text = "";
1640 $cb->($self, $ref); 1697 $cb->($_[0], $ref);
1641 1698
1642 1 1699 1
1643 } elsif ($@) { 1700 } elsif ($@) {
1644 # error case 1701 # error case
1645 $json->incr_skip; 1702 $json->incr_skip;
1646 1703
1647 $self->{rbuf} = $json->incr_text; 1704 $_[0]{rbuf} = $json->incr_text;
1648 $json->incr_text = ""; 1705 $json->incr_text = "";
1649 1706
1650 $self->_error (Errno::EBADMSG); 1707 $_[0]->_error (Errno::EBADMSG);
1651 1708
1652 () 1709 ()
1653 } else { 1710 } else {
1654 $self->{rbuf} = ""; 1711 $_[0]{rbuf} = "";
1655 1712
1656 () 1713 ()
1657 } 1714 }
1658 } 1715 }
1659}; 1716};
1669=cut 1726=cut
1670 1727
1671register_read_type storable => sub { 1728register_read_type storable => sub {
1672 my ($self, $cb) = @_; 1729 my ($self, $cb) = @_;
1673 1730
1674 require Storable; 1731 require Storable unless $Storable::VERSION;
1675 1732
1676 sub { 1733 sub {
1677 # when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method 1734 # when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
1678 defined (my $len = eval { unpack "w", $_[0]{rbuf} }) 1735 defined (my $len = eval { unpack "w", $_[0]{rbuf} })
1679 or return; 1736 or return;
1682 1739
1683 # bypass unshift if we already have the remaining chunk 1740 # bypass unshift if we already have the remaining chunk
1684 if ($format + $len <= length $_[0]{rbuf}) { 1741 if ($format + $len <= length $_[0]{rbuf}) {
1685 my $data = substr $_[0]{rbuf}, $format, $len; 1742 my $data = substr $_[0]{rbuf}, $format, $len;
1686 substr $_[0]{rbuf}, 0, $format + $len, ""; 1743 substr $_[0]{rbuf}, 0, $format + $len, "";
1744
1687 $cb->($_[0], Storable::thaw ($data)); 1745 eval { $cb->($_[0], Storable::thaw ($data)); 1 }
1746 or return $_[0]->_error (Errno::EBADMSG);
1688 } else { 1747 } else {
1689 # remove prefix 1748 # remove prefix
1690 substr $_[0]{rbuf}, 0, $format, ""; 1749 substr $_[0]{rbuf}, 0, $format, "";
1691 1750
1692 # read remaining chunk 1751 # read remaining chunk
1693 $_[0]->unshift_read (chunk => $len, sub { 1752 $_[0]->unshift_read (chunk => $len, sub {
1694 if (my $ref = eval { Storable::thaw ($_[1]) }) { 1753 eval { $cb->($_[0], Storable::thaw ($_[1])); 1 }
1695 $cb->($_[0], $ref);
1696 } else {
1697 $self->_error (Errno::EBADMSG); 1754 or $_[0]->_error (Errno::EBADMSG);
1698 }
1699 }); 1755 });
1700 } 1756 }
1701 1757
1702 1 1758 1
1703 } 1759 }
1760};
1761
1762=item tls_detect => $cb->($handle, $detect, $major, $minor)
1763
1764Checks the input stream for a valid SSL or TLS handshake TLSPaintext
1765record without consuming anything. Only SSL version 3 or higher
1766is handled, up to the fictituous protocol 4.x (but both SSL3+ and
1767SSL2-compatible framing is supported).
1768
1769If it detects that the input data is likely TLS, it calls the callback
1770with a true value for C<$detect> and the (on-wire) TLS version as second
1771and third argument (C<$major> is C<3>, and C<$minor> is 0..3 for SSL
17723.0, TLS 1.0, 1.1 and 1.2, respectively). If it detects the input to
1773be definitely not TLS, it calls the callback with a false value for
1774C<$detect>.
1775
1776The callback could use this information to decide whether or not to start
1777TLS negotiation.
1778
1779In all cases the data read so far is passed to the following read
1780handlers.
1781
1782Usually you want to use the C<tls_autostart> read type instead.
1783
1784If you want to design a protocol that works in the presence of TLS
1785dtection, make sure that any non-TLS data doesn't start with the octet 22
1786(ASCII SYN, 16 hex) or 128-255 (i.e. highest bit set). The checks this
1787read type does are a bit more strict, but might losen in the future to
1788accomodate protocol changes.
1789
1790This read type does not rely on L<AnyEvent::TLS> (and thus, not on
1791L<Net::SSLeay>).
1792
1793=item tls_autostart => $tls[, $tls_ctx]
1794
1795Tries to detect a valid SSL or TLS handshake. If one is detected, it tries
1796to start tls by calling C<starttls> with the given arguments.
1797
1798In practise, C<$tls> must be C<accept>, or a Net::SSLeay context that has
1799been configured to accept, as servers do not normally send a handshake on
1800their own and ths cannot be detected in this way.
1801
1802See C<tls_detect> above for more details.
1803
1804Example: give the client a chance to start TLS before accepting a text
1805line.
1806
1807 $hdl->push_read (tls_detect => "accept");
1808 $hdl->push_read (line => sub {
1809 print "received ", ($_[0]{tls} ? "encrypted" : "cleartext"), " <$_[1]>\n";
1810 });
1811
1812=cut
1813
1814register_read_type tls_detect => sub {
1815 my ($self, $cb) = @_;
1816
1817 sub {
1818 # this regex matches a full or partial tls record
1819 if (
1820 # ssl3+: type(22=handshake) major(=3) minor(any) length_hi
1821 $self->{rbuf} =~ /^(?:\z| \x16 (\z| [\x03\x04] (?:\z| . (?:\z| [\x00-\x40] ))))/xs
1822 # ssl2 comapatible: len_hi len_lo type(1) major minor dummy(forlength)
1823 or $self->{rbuf} =~ /^(?:\z| [\x80-\xff] (?:\z| . (?:\z| \x01 (\z| [\x03\x04] (?:\z| . (?:\z| . ))))))/xs
1824 ) {
1825 return if 3 != length $1; # partial match, can't decide yet
1826
1827 # full match, valid TLS record
1828 my ($major, $minor) = unpack "CC", $1;
1829 $cb->($self, "accept", $major + $minor * 0.1);
1830 } else {
1831 # mismatch == guaranteed not TLS
1832 $cb->($self, undef);
1833 }
1834
1835 1
1836 }
1837};
1838
1839register_read_type tls_autostart => sub {
1840 my ($self, @tls) = @_;
1841
1842 $RH{tls_detect}($self, sub {
1843 return unless $_[1];
1844 $_[0]->starttls (@tls);
1845 })
1704}; 1846};
1705 1847
1706=back 1848=back
1707 1849
1708=item custom read types - Package::anyevent_read_type $handle, $cb, @args 1850=item custom read types - Package::anyevent_read_type $handle, $cb, @args
1740Note that AnyEvent::Handle will automatically C<start_read> for you when 1882Note that AnyEvent::Handle will automatically C<start_read> for you when
1741you change the C<on_read> callback or push/unshift a read callback, and it 1883you change the C<on_read> callback or push/unshift a read callback, and it
1742will automatically C<stop_read> for you when neither C<on_read> is set nor 1884will automatically C<stop_read> for you when neither C<on_read> is set nor
1743there are any read requests in the queue. 1885there are any read requests in the queue.
1744 1886
1745These methods will have no effect when in TLS mode (as TLS doesn't support 1887In older versions of this module (<= 5.3), these methods had no effect,
1746half-duplex connections). 1888as TLS does not support half-duplex connections. In current versions they
1889work as expected, as this behaviour is required to avoid certain resource
1890attacks, where the program would be forced to read (and buffer) arbitrary
1891amounts of data before being able to send some data. The drawback is that
1892some readings of the the SSL/TLS specifications basically require this
1893attack to be working, as SSL/TLS implementations might stall sending data
1894during a rehandshake.
1895
1896As a guideline, during the initial handshake, you should not stop reading,
1897and as a client, it might cause problems, depending on your application.
1747 1898
1748=cut 1899=cut
1749 1900
1750sub stop_read { 1901sub stop_read {
1751 my ($self) = @_; 1902 my ($self) = @_;
1752 1903
1753 delete $self->{_rw} unless $self->{tls}; 1904 delete $self->{_rw};
1754} 1905}
1755 1906
1756sub start_read { 1907sub start_read {
1757 my ($self) = @_; 1908 my ($self) = @_;
1758 1909
1799 my ($self, $err) = @_; 1950 my ($self, $err) = @_;
1800 1951
1801 return $self->_error ($!, 1) 1952 return $self->_error ($!, 1)
1802 if $err == Net::SSLeay::ERROR_SYSCALL (); 1953 if $err == Net::SSLeay::ERROR_SYSCALL ();
1803 1954
1804 my $err =Net::SSLeay::ERR_error_string (Net::SSLeay::ERR_get_error ()); 1955 my $err = Net::SSLeay::ERR_error_string (Net::SSLeay::ERR_get_error ());
1805 1956
1806 # reduce error string to look less scary 1957 # reduce error string to look less scary
1807 $err =~ s/^error:[0-9a-fA-F]{8}:[^:]+:([^:]+):/\L$1: /; 1958 $err =~ s/^error:[0-9a-fA-F]{8}:[^:]+:([^:]+):/\L$1: /;
1808 1959
1809 if ($self->{_on_starttls}) { 1960 if ($self->{_on_starttls}) {
1875 2026
1876=item $handle->starttls ($tls[, $tls_ctx]) 2027=item $handle->starttls ($tls[, $tls_ctx])
1877 2028
1878Instead of starting TLS negotiation immediately when the AnyEvent::Handle 2029Instead of starting TLS negotiation immediately when the AnyEvent::Handle
1879object is created, you can also do that at a later time by calling 2030object is created, you can also do that at a later time by calling
1880C<starttls>. 2031C<starttls>. See the C<tls> constructor argument for general info.
1881 2032
1882Starting TLS is currently an asynchronous operation - when you push some 2033Starting TLS is currently an asynchronous operation - when you push some
1883write data and then call C<< ->starttls >> then TLS negotiation will start 2034write data and then call C<< ->starttls >> then TLS negotiation will start
1884immediately, after which the queued write data is then sent. 2035immediately, after which the queued write data is then sent. This might
2036change in future versions, so best make sure you have no outstanding write
2037data when calling this method.
1885 2038
1886The first argument is the same as the C<tls> constructor argument (either 2039The first argument is the same as the C<tls> constructor argument (either
1887C<"connect">, C<"accept"> or an existing Net::SSLeay object). 2040C<"connect">, C<"accept"> or an existing Net::SSLeay object).
1888 2041
1889The second argument is the optional C<AnyEvent::TLS> object that is used 2042The second argument is the optional C<AnyEvent::TLS> object that is used
1911 my ($self, $tls, $ctx) = @_; 2064 my ($self, $tls, $ctx) = @_;
1912 2065
1913 Carp::croak "It is an error to call starttls on an AnyEvent::Handle object while TLS is already active, caught" 2066 Carp::croak "It is an error to call starttls on an AnyEvent::Handle object while TLS is already active, caught"
1914 if $self->{tls}; 2067 if $self->{tls};
1915 2068
2069 unless (defined $AnyEvent::TLS::VERSION) {
2070 eval {
2071 require Net::SSLeay;
2072 require AnyEvent::TLS;
2073 1
2074 } or return $self->_error (Errno::EPROTO, 1, "TLS support not available on this system");
2075 }
2076
1916 $self->{tls} = $tls; 2077 $self->{tls} = $tls;
1917 $self->{tls_ctx} = $ctx if @_ > 2; 2078 $self->{tls_ctx} = $ctx if @_ > 2;
1918 2079
1919 return unless $self->{fh}; 2080 return unless $self->{fh};
1920 2081
1921 require Net::SSLeay;
1922
1923 $ERROR_SYSCALL = Net::SSLeay::ERROR_SYSCALL (); 2082 $ERROR_SYSCALL = Net::SSLeay::ERROR_SYSCALL ();
1924 $ERROR_WANT_READ = Net::SSLeay::ERROR_WANT_READ (); 2083 $ERROR_WANT_READ = Net::SSLeay::ERROR_WANT_READ ();
1925 2084
1926 $tls = delete $self->{tls}; 2085 $tls = delete $self->{tls};
1927 $ctx = $self->{tls_ctx}; 2086 $ctx = $self->{tls_ctx};
1928 2087
1929 local $Carp::CarpLevel = 1; # skip ourselves when creating a new context or session 2088 local $Carp::CarpLevel = 1; # skip ourselves when creating a new context or session
1930 2089
1931 if ("HASH" eq ref $ctx) { 2090 if ("HASH" eq ref $ctx) {
1932 require AnyEvent::TLS;
1933
1934 if ($ctx->{cache}) { 2091 if ($ctx->{cache}) {
1935 my $key = $ctx+0; 2092 my $key = $ctx+0;
1936 $ctx = $TLS_CACHE{$key} ||= new AnyEvent::TLS %$ctx; 2093 $ctx = $TLS_CACHE{$key} ||= new AnyEvent::TLS %$ctx;
1937 } else { 2094 } else {
1938 $ctx = new AnyEvent::TLS %$ctx; 2095 $ctx = new AnyEvent::TLS %$ctx;
1960 Net::SSLeay::CTX_set_mode ($tls, 1|2); 2117 Net::SSLeay::CTX_set_mode ($tls, 1|2);
1961 2118
1962 $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); 2119 $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1963 $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); 2120 $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1964 2121
1965 Net::SSLeay::BIO_write ($self->{_rbio}, delete $self->{rbuf}); 2122 Net::SSLeay::BIO_write ($self->{_rbio}, $self->{rbuf});
2123 $self->{rbuf} = "";
1966 2124
1967 Net::SSLeay::set_bio ($tls, $self->{_rbio}, $self->{_wbio}); 2125 Net::SSLeay::set_bio ($tls, $self->{_rbio}, $self->{_wbio});
1968 2126
1969 $self->{_on_starttls} = sub { $_[0]{on_starttls}(@_) } 2127 $self->{_on_starttls} = sub { $_[0]{on_starttls}(@_) }
1970 if $self->{on_starttls}; 2128 if $self->{on_starttls};
2007 $self->{tls_ctx}->_put_session (delete $self->{tls}) 2165 $self->{tls_ctx}->_put_session (delete $self->{tls})
2008 if $self->{tls} > 0; 2166 if $self->{tls} > 0;
2009 2167
2010 delete @$self{qw(_rbio _wbio _tls_wbuf _on_starttls)}; 2168 delete @$self{qw(_rbio _wbio _tls_wbuf _on_starttls)};
2011} 2169}
2170
2171=item $handle->resettls
2172
2173This rarely-used method simply resets and TLS state on the handle, usually
2174causing data loss.
2175
2176One case where it may be useful is when you want to skip over the data in
2177the stream but you are not interested in interpreting it, so data loss is
2178no concern.
2179
2180=cut
2181
2182*resettls = \&_freetls;
2012 2183
2013sub DESTROY { 2184sub DESTROY {
2014 my ($self) = @_; 2185 my ($self) = @_;
2015 2186
2016 &_freetls; 2187 &_freetls;
2132 2303
2133It is only safe to "forget" the reference inside EOF or error callbacks, 2304It is only safe to "forget" the reference inside EOF or error callbacks,
2134from within all other callbacks, you need to explicitly call the C<< 2305from within all other callbacks, you need to explicitly call the C<<
2135->destroy >> method. 2306->destroy >> method.
2136 2307
2308=item Why is my C<on_eof> callback never called?
2309
2310Probably because your C<on_error> callback is being called instead: When
2311you have outstanding requests in your read queue, then an EOF is
2312considered an error as you clearly expected some data.
2313
2314To avoid this, make sure you have an empty read queue whenever your handle
2315is supposed to be "idle" (i.e. connection closes are O.K.). You can set
2316an C<on_read> handler that simply pushes the first read requests in the
2317queue.
2318
2319See also the next question, which explains this in a bit more detail.
2320
2321=item How can I serve requests in a loop?
2322
2323Most protocols consist of some setup phase (authentication for example)
2324followed by a request handling phase, where the server waits for requests
2325and handles them, in a loop.
2326
2327There are two important variants: The first (traditional, better) variant
2328handles requests until the server gets some QUIT command, causing it to
2329close the connection first (highly desirable for a busy TCP server). A
2330client dropping the connection is an error, which means this variant can
2331detect an unexpected detection close.
2332
2333To handle this case, always make sure you have a non-empty read queue, by
2334pushing the "read request start" handler on it:
2335
2336 # we assume a request starts with a single line
2337 my @start_request; @start_request = (line => sub {
2338 my ($hdl, $line) = @_;
2339
2340 ... handle request
2341
2342 # push next request read, possibly from a nested callback
2343 $hdl->push_read (@start_request);
2344 });
2345
2346 # auth done, now go into request handling loop
2347 # now push the first @start_request
2348 $hdl->push_read (@start_request);
2349
2350By always having an outstanding C<push_read>, the handle always expects
2351some data and raises the C<EPIPE> error when the connction is dropped
2352unexpectedly.
2353
2354The second variant is a protocol where the client can drop the connection
2355at any time. For TCP, this means that the server machine may run out of
2356sockets easier, and in general, it means you cannot distinguish a protocl
2357failure/client crash from a normal connection close. Nevertheless, these
2358kinds of protocols are common (and sometimes even the best solution to the
2359problem).
2360
2361Having an outstanding read request at all times is possible if you ignore
2362C<EPIPE> errors, but this doesn't help with when the client drops the
2363connection during a request, which would still be an error.
2364
2365A better solution is to push the initial request read in an C<on_read>
2366callback. This avoids an error, as when the server doesn't expect data
2367(i.e. is idly waiting for the next request, an EOF will not raise an
2368error, but simply result in an C<on_eof> callback. It is also a bit slower
2369and simpler:
2370
2371 # auth done, now go into request handling loop
2372 $hdl->on_read (sub {
2373 my ($hdl) = @_;
2374
2375 # called each time we receive data but the read queue is empty
2376 # simply start read the request
2377
2378 $hdl->push_read (line => sub {
2379 my ($hdl, $line) = @_;
2380
2381 ... handle request
2382
2383 # do nothing special when the request has been handled, just
2384 # let the request queue go empty.
2385 });
2386 });
2387
2137=item I get different callback invocations in TLS mode/Why can't I pause 2388=item I get different callback invocations in TLS mode/Why can't I pause
2138reading? 2389reading?
2139 2390
2140Unlike, say, TCP, TLS connections do not consist of two independent 2391Unlike, say, TCP, TLS connections do not consist of two independent
2141communication channels, one for each direction. Or put differently, the 2392communication channels, one for each direction. Or put differently, the
2162 $handle->on_eof (undef); 2413 $handle->on_eof (undef);
2163 $handle->on_error (sub { 2414 $handle->on_error (sub {
2164 my $data = delete $_[0]{rbuf}; 2415 my $data = delete $_[0]{rbuf};
2165 }); 2416 });
2166 2417
2418Note that this example removes the C<rbuf> member from the handle object,
2419which is not normally allowed by the API. It is expressly permitted in
2420this case only, as the handle object needs to be destroyed afterwards.
2421
2167The reason to use C<on_error> is that TCP connections, due to latencies 2422The reason to use C<on_error> is that TCP connections, due to latencies
2168and packets loss, might get closed quite violently with an error, when in 2423and packets loss, might get closed quite violently with an error, when in
2169fact all data has been received. 2424fact all data has been received.
2170 2425
2171It is usually better to use acknowledgements when transferring data, 2426It is usually better to use acknowledgements when transferring data,
2181C<low_water_mark> this will be called precisely when all data has been 2436C<low_water_mark> this will be called precisely when all data has been
2182written to the socket: 2437written to the socket:
2183 2438
2184 $handle->push_write (...); 2439 $handle->push_write (...);
2185 $handle->on_drain (sub { 2440 $handle->on_drain (sub {
2186 warn "all data submitted to the kernel\n"; 2441 AE::log debug => "All data submitted to the kernel.";
2187 undef $handle; 2442 undef $handle;
2188 }); 2443 });
2189 2444
2190If you just want to queue some data and then signal EOF to the other side, 2445If you just want to queue some data and then signal EOF to the other side,
2191consider using C<< ->push_shutdown >> instead. 2446consider using C<< ->push_shutdown >> instead.
2275When you have intermediate CA certificates that your clients might not 2530When you have intermediate CA certificates that your clients might not
2276know about, just append them to the C<cert_file>. 2531know about, just append them to the C<cert_file>.
2277 2532
2278=back 2533=back
2279 2534
2280
2281=head1 SUBCLASSING AnyEvent::Handle 2535=head1 SUBCLASSING AnyEvent::Handle
2282 2536
2283In many cases, you might want to subclass AnyEvent::Handle. 2537In many cases, you might want to subclass AnyEvent::Handle.
2284 2538
2285To make this easier, a given version of AnyEvent::Handle uses these 2539To make this easier, a given version of AnyEvent::Handle uses these
2311 2565
2312Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>. 2566Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>.
2313 2567
2314=cut 2568=cut
2315 2569
23161; # End of AnyEvent::Handle 25701
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