… | |
… | |
75 | } |
75 | } |
76 | |
76 | |
77 | \&$func |
77 | \&$func |
78 | } |
78 | } |
79 | |
79 | |
|
|
80 | sub MAX_READ_SIZE() { 131072 } |
|
|
81 | |
80 | =head1 METHODS |
82 | =head1 METHODS |
81 | |
83 | |
82 | =over 4 |
84 | =over 4 |
83 | |
85 | |
84 | =item $handle = B<new> AnyEvent::Handle fh => $filehandle, key => value... |
86 | =item $handle = B<new> AnyEvent::Handle fh => $filehandle, key => value... |
… | |
… | |
112 | =over 4 |
114 | =over 4 |
113 | |
115 | |
114 | =item on_prepare => $cb->($handle) |
116 | =item on_prepare => $cb->($handle) |
115 | |
117 | |
116 | This (rarely used) callback is called before a new connection is |
118 | This (rarely used) callback is called before a new connection is |
117 | attempted, but after the file handle has been created. It could be used to |
119 | attempted, but after the file handle has been created (you can access that |
|
|
120 | file handle via C<< $handle->{fh} >>). It could be used to prepare the |
118 | prepare the file handle with parameters required for the actual connect |
121 | file handle with parameters required for the actual connect (as opposed to |
119 | (as opposed to settings that can be changed when the connection is already |
122 | settings that can be changed when the connection is already established). |
120 | established). |
|
|
121 | |
123 | |
122 | The return value of this callback should be the connect timeout value in |
124 | The return value of this callback should be the connect timeout value in |
123 | seconds (or C<0>, or C<undef>, or the empty list, to indicate that the |
125 | seconds (or C<0>, or C<undef>, or the empty list, to indicate that the |
124 | default timeout is to be used). |
126 | default timeout is to be used). |
125 | |
127 | |
… | |
… | |
157 | |
159 | |
158 | Some errors are fatal (which is indicated by C<$fatal> being true). On |
160 | Some errors are fatal (which is indicated by C<$fatal> being true). On |
159 | fatal errors the handle object will be destroyed (by a call to C<< -> |
161 | fatal errors the handle object will be destroyed (by a call to C<< -> |
160 | destroy >>) after invoking the error callback (which means you are free to |
162 | destroy >>) after invoking the error callback (which means you are free to |
161 | examine the handle object). Examples of fatal errors are an EOF condition |
163 | examine the handle object). Examples of fatal errors are an EOF condition |
162 | with active (but unsatisifable) read watchers (C<EPIPE>) or I/O errors. In |
164 | with active (but unsatisfiable) read watchers (C<EPIPE>) or I/O errors. In |
163 | cases where the other side can close the connection at will, it is |
165 | cases where the other side can close the connection at will, it is |
164 | often easiest to not report C<EPIPE> errors in this callback. |
166 | often easiest to not report C<EPIPE> errors in this callback. |
165 | |
167 | |
166 | AnyEvent::Handle tries to find an appropriate error code for you to check |
168 | AnyEvent::Handle tries to find an appropriate error code for you to check |
167 | against, but in some cases (TLS errors), this does not work well. It is |
169 | against, but in some cases (TLS errors), this does not work well. It is |
… | |
… | |
245 | many seconds pass without a successful read or write on the underlying |
247 | many seconds pass without a successful read or write on the underlying |
246 | file handle (or a call to C<timeout_reset>), the C<on_timeout> callback |
248 | file handle (or a call to C<timeout_reset>), the C<on_timeout> callback |
247 | will be invoked (and if that one is missing, a non-fatal C<ETIMEDOUT> |
249 | will be invoked (and if that one is missing, a non-fatal C<ETIMEDOUT> |
248 | error will be raised). |
250 | error will be raised). |
249 | |
251 | |
250 | There are three variants of the timeouts that work independently |
252 | There are three variants of the timeouts that work independently of each |
251 | of each other, for both read and write, just read, and just write: |
253 | other, for both read and write (triggered when nothing was read I<OR> |
|
|
254 | written), just read (triggered when nothing was read), and just write: |
252 | C<timeout>, C<rtimeout> and C<wtimeout>, with corresponding callbacks |
255 | C<timeout>, C<rtimeout> and C<wtimeout>, with corresponding callbacks |
253 | C<on_timeout>, C<on_rtimeout> and C<on_wtimeout>, and reset functions |
256 | C<on_timeout>, C<on_rtimeout> and C<on_wtimeout>, and reset functions |
254 | C<timeout_reset>, C<rtimeout_reset>, and C<wtimeout_reset>. |
257 | C<timeout_reset>, C<rtimeout_reset>, and C<wtimeout_reset>. |
255 | |
258 | |
256 | Note that timeout processing is active even when you do not have |
259 | Note that timeout processing is active even when you do not have any |
257 | any outstanding read or write requests: If you plan to keep the connection |
260 | outstanding read or write requests: If you plan to keep the connection |
258 | idle then you should disable the timeout temporarily or ignore the timeout |
261 | idle then you should disable the timeout temporarily or ignore the |
259 | in the C<on_timeout> callback, in which case AnyEvent::Handle will simply |
262 | timeout in the corresponding C<on_timeout> callback, in which case |
260 | restart the timeout. |
263 | AnyEvent::Handle will simply restart the timeout. |
261 | |
264 | |
262 | Zero (the default) disables this timeout. |
265 | Zero (the default) disables the corresponding timeout. |
263 | |
266 | |
264 | =item on_timeout => $cb->($handle) |
267 | =item on_timeout => $cb->($handle) |
|
|
268 | |
|
|
269 | =item on_rtimeout => $cb->($handle) |
|
|
270 | |
|
|
271 | =item on_wtimeout => $cb->($handle) |
265 | |
272 | |
266 | Called whenever the inactivity timeout passes. If you return from this |
273 | Called whenever the inactivity timeout passes. If you return from this |
267 | callback, then the timeout will be reset as if some activity had happened, |
274 | callback, then the timeout will be reset as if some activity had happened, |
268 | so this condition is not fatal in any way. |
275 | so this condition is not fatal in any way. |
269 | |
276 | |
… | |
… | |
276 | For example, a server accepting connections from untrusted sources should |
283 | For example, a server accepting connections from untrusted sources should |
277 | be configured to accept only so-and-so much data that it cannot act on |
284 | be configured to accept only so-and-so much data that it cannot act on |
278 | (for example, when expecting a line, an attacker could send an unlimited |
285 | (for example, when expecting a line, an attacker could send an unlimited |
279 | amount of data without a callback ever being called as long as the line |
286 | amount of data without a callback ever being called as long as the line |
280 | isn't finished). |
287 | isn't finished). |
|
|
288 | |
|
|
289 | =item wbuf_max => <bytes> |
|
|
290 | |
|
|
291 | If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>) |
|
|
292 | when the write buffer ever (strictly) exceeds this size. This is useful to |
|
|
293 | avoid some forms of denial-of-service attacks. |
|
|
294 | |
|
|
295 | Although the units of this parameter is bytes, this is the I<raw> number |
|
|
296 | of bytes not yet accepted by the kernel. This can make a difference when |
|
|
297 | you e.g. use TLS, as TLS typically makes your write data larger (but it |
|
|
298 | can also make it smaller due to compression). |
|
|
299 | |
|
|
300 | As an example of when this limit is useful, take a chat server that sends |
|
|
301 | chat messages to a client. If the client does not read those in a timely |
|
|
302 | manner then the send buffer in the server would grow unbounded. |
281 | |
303 | |
282 | =item autocork => <boolean> |
304 | =item autocork => <boolean> |
283 | |
305 | |
284 | When disabled (the default), C<push_write> will try to immediately |
306 | When disabled (the default), C<push_write> will try to immediately |
285 | write the data to the handle if possible. This avoids having to register |
307 | write the data to the handle if possible. This avoids having to register |
… | |
… | |
337 | already have occured on BSD systems), but at least it will protect you |
359 | already have occured on BSD systems), but at least it will protect you |
338 | from most attacks. |
360 | from most attacks. |
339 | |
361 | |
340 | =item read_size => <bytes> |
362 | =item read_size => <bytes> |
341 | |
363 | |
342 | The default read block size (the number of bytes this module will |
364 | The initial read block size, the number of bytes this module will try to |
343 | try to read during each loop iteration, which affects memory |
365 | read during each loop iteration. Each handle object will consume at least |
344 | requirements). Default: C<8192>. |
366 | this amount of memory for the read buffer as well, so when handling many |
|
|
367 | connections requirements). See also C<max_read_size>. Default: C<2048>. |
|
|
368 | |
|
|
369 | =item max_read_size => <bytes> |
|
|
370 | |
|
|
371 | The maximum read buffer size used by the dynamic adjustment |
|
|
372 | algorithm: Each time AnyEvent::Handle can read C<read_size> bytes in |
|
|
373 | one go it will double C<read_size> up to the maximum given by this |
|
|
374 | option. Default: C<131072> or C<read_size>, whichever is higher. |
345 | |
375 | |
346 | =item low_water_mark => <bytes> |
376 | =item low_water_mark => <bytes> |
347 | |
377 | |
348 | Sets the number of bytes (default: C<0>) that make up an "empty" write |
378 | Sets the number of bytes (default: C<0>) that make up an "empty" write |
349 | buffer: If the buffer reaches this size or gets even samller it is |
379 | buffer: If the buffer reaches this size or gets even samller it is |
… | |
… | |
412 | Use the C<< ->starttls >> method if you need to start TLS negotiation later. |
442 | Use the C<< ->starttls >> method if you need to start TLS negotiation later. |
413 | |
443 | |
414 | =item tls_ctx => $anyevent_tls |
444 | =item tls_ctx => $anyevent_tls |
415 | |
445 | |
416 | Use the given C<AnyEvent::TLS> object to create the new TLS connection |
446 | Use the given C<AnyEvent::TLS> object to create the new TLS connection |
417 | (unless a connection object was specified directly). If this parameter is |
447 | (unless a connection object was specified directly). If this |
418 | missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>. |
448 | parameter is missing (or C<undef>), then AnyEvent::Handle will use |
|
|
449 | C<AnyEvent::Handle::TLS_CTX>. |
419 | |
450 | |
420 | Instead of an object, you can also specify a hash reference with C<< key |
451 | Instead of an object, you can also specify a hash reference with C<< key |
421 | => value >> pairs. Those will be passed to L<AnyEvent::TLS> to create a |
452 | => value >> pairs. Those will be passed to L<AnyEvent::TLS> to create a |
422 | new TLS context object. |
453 | new TLS context object. |
423 | |
454 | |
… | |
… | |
492 | $self->{connect}[0], |
523 | $self->{connect}[0], |
493 | $self->{connect}[1], |
524 | $self->{connect}[1], |
494 | sub { |
525 | sub { |
495 | my ($fh, $host, $port, $retry) = @_; |
526 | my ($fh, $host, $port, $retry) = @_; |
496 | |
527 | |
|
|
528 | delete $self->{_connect}; # no longer needed |
|
|
529 | |
497 | if ($fh) { |
530 | if ($fh) { |
498 | $self->{fh} = $fh; |
531 | $self->{fh} = $fh; |
499 | |
532 | |
500 | delete $self->{_skip_drain_rbuf}; |
533 | delete $self->{_skip_drain_rbuf}; |
501 | $self->_start; |
534 | $self->_start; |
… | |
… | |
508 | }); |
541 | }); |
509 | |
542 | |
510 | } else { |
543 | } else { |
511 | if ($self->{on_connect_error}) { |
544 | if ($self->{on_connect_error}) { |
512 | $self->{on_connect_error}($self, "$!"); |
545 | $self->{on_connect_error}($self, "$!"); |
513 | $self->destroy; |
546 | $self->destroy if $self; |
514 | } else { |
547 | } else { |
515 | $self->_error ($!, 1); |
548 | $self->_error ($!, 1); |
516 | } |
549 | } |
517 | } |
550 | } |
518 | }, |
551 | }, |
519 | sub { |
552 | sub { |
520 | local $self->{fh} = $_[0]; |
553 | local $self->{fh} = $_[0]; |
521 | |
554 | |
522 | $self->{on_prepare} |
555 | $self->{on_prepare} |
523 | ? $self->{on_prepare}->($self) |
556 | ? $self->{on_prepare}->($self) |
524 | : () |
557 | : () |
525 | } |
558 | } |
526 | ); |
559 | ); |
527 | } |
560 | } |
528 | |
561 | |
… | |
… | |
546 | |
579 | |
547 | $self->{_activity} = |
580 | $self->{_activity} = |
548 | $self->{_ractivity} = |
581 | $self->{_ractivity} = |
549 | $self->{_wactivity} = AE::now; |
582 | $self->{_wactivity} = AE::now; |
550 | |
583 | |
|
|
584 | $self->{read_size} ||= 2048; |
|
|
585 | $self->{max_read_size} = $self->{read_size} |
|
|
586 | if $self->{read_size} > ($self->{max_read_size} || MAX_READ_SIZE); |
|
|
587 | |
551 | $self->timeout (delete $self->{timeout} ) if $self->{timeout}; |
588 | $self->timeout (delete $self->{timeout} ) if $self->{timeout}; |
552 | $self->rtimeout (delete $self->{rtimeout} ) if $self->{rtimeout}; |
589 | $self->rtimeout (delete $self->{rtimeout} ) if $self->{rtimeout}; |
553 | $self->wtimeout (delete $self->{wtimeout} ) if $self->{wtimeout}; |
590 | $self->wtimeout (delete $self->{wtimeout} ) if $self->{wtimeout}; |
554 | |
591 | |
555 | $self->no_delay (delete $self->{no_delay} ) if exists $self->{no_delay} && $self->{no_delay}; |
592 | $self->no_delay (delete $self->{no_delay} ) if exists $self->{no_delay} && $self->{no_delay}; |
… | |
… | |
558 | $self->oobinline (exists $self->{oobinline} ? delete $self->{oobinline} : 1); |
595 | $self->oobinline (exists $self->{oobinline} ? delete $self->{oobinline} : 1); |
559 | |
596 | |
560 | $self->starttls (delete $self->{tls}, delete $self->{tls_ctx}) |
597 | $self->starttls (delete $self->{tls}, delete $self->{tls_ctx}) |
561 | if $self->{tls}; |
598 | if $self->{tls}; |
562 | |
599 | |
563 | $self->on_drain (delete $self->{on_drain}) if $self->{on_drain}; |
600 | $self->on_drain (delete $self->{on_drain} ) if $self->{on_drain}; |
564 | |
601 | |
565 | $self->start_read |
602 | $self->start_read |
566 | if $self->{on_read} || @{ $self->{_queue} }; |
603 | if $self->{on_read} || @{ $self->{_queue} }; |
567 | |
604 | |
568 | $self->_drain_wbuf; |
605 | $self->_drain_wbuf; |
… | |
… | |
644 | =cut |
681 | =cut |
645 | |
682 | |
646 | sub no_delay { |
683 | sub no_delay { |
647 | $_[0]{no_delay} = $_[1]; |
684 | $_[0]{no_delay} = $_[1]; |
648 | |
685 | |
649 | eval { |
|
|
650 | local $SIG{__DIE__}; |
|
|
651 | setsockopt $_[0]{fh}, Socket::IPPROTO_TCP (), Socket::TCP_NODELAY (), int $_[1] |
686 | setsockopt $_[0]{fh}, Socket::IPPROTO_TCP (), Socket::TCP_NODELAY (), int $_[1] |
652 | if $_[0]{fh}; |
687 | if $_[0]{fh}; |
653 | }; |
|
|
654 | } |
688 | } |
655 | |
689 | |
656 | =item $handle->keepalive ($boolean) |
690 | =item $handle->keepalive ($boolean) |
657 | |
691 | |
658 | Enables or disables the C<keepalive> setting (see constructor argument of |
692 | Enables or disables the C<keepalive> setting (see constructor argument of |
… | |
… | |
726 | |
760 | |
727 | =item $handle->rbuf_max ($max_octets) |
761 | =item $handle->rbuf_max ($max_octets) |
728 | |
762 | |
729 | Configures the C<rbuf_max> setting (C<undef> disables it). |
763 | Configures the C<rbuf_max> setting (C<undef> disables it). |
730 | |
764 | |
|
|
765 | =item $handle->wbuf_max ($max_octets) |
|
|
766 | |
|
|
767 | Configures the C<wbuf_max> setting (C<undef> disables it). |
|
|
768 | |
731 | =cut |
769 | =cut |
732 | |
770 | |
733 | sub rbuf_max { |
771 | sub rbuf_max { |
734 | $_[0]{rbuf_max} = $_[1]; |
772 | $_[0]{rbuf_max} = $_[1]; |
735 | } |
773 | } |
736 | |
774 | |
|
|
775 | sub wbuf_max { |
|
|
776 | $_[0]{wbuf_max} = $_[1]; |
|
|
777 | } |
|
|
778 | |
737 | ############################################################################# |
779 | ############################################################################# |
738 | |
780 | |
739 | =item $handle->timeout ($seconds) |
781 | =item $handle->timeout ($seconds) |
740 | |
782 | |
741 | =item $handle->rtimeout ($seconds) |
783 | =item $handle->rtimeout ($seconds) |
742 | |
784 | |
743 | =item $handle->wtimeout ($seconds) |
785 | =item $handle->wtimeout ($seconds) |
744 | |
786 | |
745 | Configures (or disables) the inactivity timeout. |
787 | Configures (or disables) the inactivity timeout. |
|
|
788 | |
|
|
789 | The timeout will be checked instantly, so this method might destroy the |
|
|
790 | handle before it returns. |
746 | |
791 | |
747 | =item $handle->timeout_reset |
792 | =item $handle->timeout_reset |
748 | |
793 | |
749 | =item $handle->rtimeout_reset |
794 | =item $handle->rtimeout_reset |
750 | |
795 | |
… | |
… | |
767 | $_[0]{$on_timeout} = $_[1]; |
812 | $_[0]{$on_timeout} = $_[1]; |
768 | }; |
813 | }; |
769 | |
814 | |
770 | *$timeout = sub { |
815 | *$timeout = sub { |
771 | my ($self, $new_value) = @_; |
816 | my ($self, $new_value) = @_; |
|
|
817 | |
|
|
818 | $new_value >= 0 |
|
|
819 | or Carp::croak "AnyEvent::Handle->$timeout called with negative timeout ($new_value), caught"; |
772 | |
820 | |
773 | $self->{$timeout} = $new_value; |
821 | $self->{$timeout} = $new_value; |
774 | delete $self->{$tw}; &$cb; |
822 | delete $self->{$tw}; &$cb; |
775 | }; |
823 | }; |
776 | |
824 | |
… | |
… | |
856 | if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf}); |
904 | if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf}); |
857 | } |
905 | } |
858 | |
906 | |
859 | =item $handle->push_write ($data) |
907 | =item $handle->push_write ($data) |
860 | |
908 | |
861 | Queues the given scalar to be written. You can push as much data as you |
909 | Queues the given scalar to be written. You can push as much data as |
862 | want (only limited by the available memory), as C<AnyEvent::Handle> |
910 | you want (only limited by the available memory and C<wbuf_max>), as |
863 | buffers it independently of the kernel. |
911 | C<AnyEvent::Handle> buffers it independently of the kernel. |
864 | |
912 | |
865 | This method may invoke callbacks (and therefore the handle might be |
913 | This method may invoke callbacks (and therefore the handle might be |
866 | destroyed after it returns). |
914 | destroyed after it returns). |
867 | |
915 | |
868 | =cut |
916 | =cut |
… | |
… | |
896 | $cb->() unless $self->{autocork}; |
944 | $cb->() unless $self->{autocork}; |
897 | |
945 | |
898 | # if still data left in wbuf, we need to poll |
946 | # if still data left in wbuf, we need to poll |
899 | $self->{_ww} = AE::io $self->{fh}, 1, $cb |
947 | $self->{_ww} = AE::io $self->{fh}, 1, $cb |
900 | if length $self->{wbuf}; |
948 | if length $self->{wbuf}; |
|
|
949 | |
|
|
950 | if ( |
|
|
951 | defined $self->{wbuf_max} |
|
|
952 | && $self->{wbuf_max} < length $self->{wbuf} |
|
|
953 | ) { |
|
|
954 | $self->_error (Errno::ENOSPC, 1), return; |
|
|
955 | } |
901 | }; |
956 | }; |
902 | } |
957 | } |
903 | |
958 | |
904 | our %WH; |
959 | our %WH; |
905 | |
960 | |
… | |
… | |
1040 | before it was actually written. One way to do that is to replace your |
1095 | before it was actually written. One way to do that is to replace your |
1041 | C<on_drain> handler by a callback that shuts down the socket (and set |
1096 | C<on_drain> handler by a callback that shuts down the socket (and set |
1042 | C<low_water_mark> to C<0>). This method is a shorthand for just that, and |
1097 | C<low_water_mark> to C<0>). This method is a shorthand for just that, and |
1043 | replaces the C<on_drain> callback with: |
1098 | replaces the C<on_drain> callback with: |
1044 | |
1099 | |
1045 | sub { shutdown $_[0]{fh}, 1 } # for push_shutdown |
1100 | sub { shutdown $_[0]{fh}, 1 } |
1046 | |
1101 | |
1047 | This simply shuts down the write side and signals an EOF condition to the |
1102 | This simply shuts down the write side and signals an EOF condition to the |
1048 | the peer. |
1103 | the peer. |
1049 | |
1104 | |
1050 | You can rely on the normal read queue and C<on_eof> handling |
1105 | You can rely on the normal read queue and C<on_eof> handling |
… | |
… | |
1271 | $self->_drain_rbuf if $cb; |
1326 | $self->_drain_rbuf if $cb; |
1272 | } |
1327 | } |
1273 | |
1328 | |
1274 | =item $handle->rbuf |
1329 | =item $handle->rbuf |
1275 | |
1330 | |
1276 | Returns the read buffer (as a modifiable lvalue). |
1331 | Returns the read buffer (as a modifiable lvalue). You can also access the |
|
|
1332 | read buffer directly as the C<< ->{rbuf} >> member, if you want (this is |
|
|
1333 | much faster, and no less clean). |
1277 | |
1334 | |
1278 | You can access the read buffer directly as the C<< ->{rbuf} >> |
1335 | The only operation allowed on the read buffer (apart from looking at it) |
1279 | member, if you want. However, the only operation allowed on the |
1336 | is removing data from its beginning. Otherwise modifying or appending to |
1280 | read buffer (apart from looking at it) is removing data from its |
1337 | it is not allowed and will lead to hard-to-track-down bugs. |
1281 | beginning. Otherwise modifying or appending to it is not allowed and will |
|
|
1282 | lead to hard-to-track-down bugs. |
|
|
1283 | |
1338 | |
1284 | NOTE: The read buffer should only be used or modified if the C<on_read>, |
1339 | NOTE: The read buffer should only be used or modified in the C<on_read> |
1285 | C<push_read> or C<unshift_read> methods are used. The other read methods |
1340 | callback or when C<push_read> or C<unshift_read> are used with a single |
1286 | automatically manage the read buffer. |
1341 | callback (i.e. untyped). Typed C<push_read> and C<unshift_read> methods |
|
|
1342 | will manage the read buffer on their own. |
1287 | |
1343 | |
1288 | =cut |
1344 | =cut |
1289 | |
1345 | |
1290 | sub rbuf : lvalue { |
1346 | sub rbuf : lvalue { |
1291 | $_[0]{rbuf} |
1347 | $_[0]{rbuf} |
… | |
… | |
1342 | my $cb = pop; |
1398 | my $cb = pop; |
1343 | |
1399 | |
1344 | if (@_) { |
1400 | if (@_) { |
1345 | my $type = shift; |
1401 | my $type = shift; |
1346 | |
1402 | |
|
|
1403 | $cb = ($RH{$type} ||= _load_func "$type\::anyevent_read_type" |
1347 | $cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::unshift_read") |
1404 | or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::unshift_read") |
1348 | ->($self, $cb, @_); |
1405 | ->($self, $cb, @_); |
1349 | } |
1406 | } |
1350 | |
1407 | |
1351 | unshift @{ $self->{_queue} }, $cb; |
1408 | unshift @{ $self->{_queue} }, $cb; |
1352 | $self->_drain_rbuf; |
1409 | $self->_drain_rbuf; |
… | |
… | |
1724 | Note that AnyEvent::Handle will automatically C<start_read> for you when |
1781 | Note that AnyEvent::Handle will automatically C<start_read> for you when |
1725 | you change the C<on_read> callback or push/unshift a read callback, and it |
1782 | you change the C<on_read> callback or push/unshift a read callback, and it |
1726 | will automatically C<stop_read> for you when neither C<on_read> is set nor |
1783 | will automatically C<stop_read> for you when neither C<on_read> is set nor |
1727 | there are any read requests in the queue. |
1784 | there are any read requests in the queue. |
1728 | |
1785 | |
1729 | These methods will have no effect when in TLS mode (as TLS doesn't support |
1786 | In older versions of this module (<= 5.3), these methods had no effect, |
1730 | half-duplex connections). |
1787 | as TLS does not support half-duplex connections. In current versions they |
|
|
1788 | work as expected, as this behaviour is required to avoid certain resource |
|
|
1789 | attacks, where the program would be forced to read (and buffer) arbitrary |
|
|
1790 | amounts of data before being able to send some data. The drawback is that |
|
|
1791 | some readings of the the SSL/TLS specifications basically require this |
|
|
1792 | attack to be working, as SSL/TLS implementations might stall sending data |
|
|
1793 | during a rehandshake. |
|
|
1794 | |
|
|
1795 | As a guideline, during the initial handshake, you should not stop reading, |
|
|
1796 | and as a client, it might cause problems, depending on your applciation. |
1731 | |
1797 | |
1732 | =cut |
1798 | =cut |
1733 | |
1799 | |
1734 | sub stop_read { |
1800 | sub stop_read { |
1735 | my ($self) = @_; |
1801 | my ($self) = @_; |
1736 | |
1802 | |
1737 | delete $self->{_rw} unless $self->{tls}; |
1803 | delete $self->{_rw}; |
1738 | } |
1804 | } |
1739 | |
1805 | |
1740 | sub start_read { |
1806 | sub start_read { |
1741 | my ($self) = @_; |
1807 | my ($self) = @_; |
1742 | |
1808 | |
1743 | unless ($self->{_rw} || $self->{_eof} || !$self->{fh}) { |
1809 | unless ($self->{_rw} || $self->{_eof} || !$self->{fh}) { |
1744 | Scalar::Util::weaken $self; |
1810 | Scalar::Util::weaken $self; |
1745 | |
1811 | |
1746 | $self->{_rw} = AE::io $self->{fh}, 0, sub { |
1812 | $self->{_rw} = AE::io $self->{fh}, 0, sub { |
1747 | my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf}); |
1813 | my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf}); |
1748 | my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf; |
1814 | my $len = sysread $self->{fh}, $$rbuf, $self->{read_size}, length $$rbuf; |
1749 | |
1815 | |
1750 | if ($len > 0) { |
1816 | if ($len > 0) { |
1751 | $self->{_activity} = $self->{_ractivity} = AE::now; |
1817 | $self->{_activity} = $self->{_ractivity} = AE::now; |
1752 | |
1818 | |
1753 | if ($self->{tls}) { |
1819 | if ($self->{tls}) { |
1754 | Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf); |
1820 | Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf); |
1755 | |
1821 | |
1756 | &_dotls ($self); |
1822 | &_dotls ($self); |
1757 | } else { |
1823 | } else { |
1758 | $self->_drain_rbuf; |
1824 | $self->_drain_rbuf; |
|
|
1825 | } |
|
|
1826 | |
|
|
1827 | if ($len == $self->{read_size}) { |
|
|
1828 | $self->{read_size} *= 2; |
|
|
1829 | $self->{read_size} = $self->{max_read_size} || MAX_READ_SIZE |
|
|
1830 | if $self->{read_size} > ($self->{max_read_size} || MAX_READ_SIZE); |
1759 | } |
1831 | } |
1760 | |
1832 | |
1761 | } elsif (defined $len) { |
1833 | } elsif (defined $len) { |
1762 | delete $self->{_rw}; |
1834 | delete $self->{_rw}; |
1763 | $self->{_eof} = 1; |
1835 | $self->{_eof} = 1; |
… | |
… | |
1938 | Net::SSLeay::CTX_set_mode ($tls, 1|2); |
2010 | Net::SSLeay::CTX_set_mode ($tls, 1|2); |
1939 | |
2011 | |
1940 | $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); |
2012 | $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); |
1941 | $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); |
2013 | $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); |
1942 | |
2014 | |
1943 | Net::SSLeay::BIO_write ($self->{_rbio}, delete $self->{rbuf}); |
2015 | Net::SSLeay::BIO_write ($self->{_rbio}, $self->{rbuf}); |
|
|
2016 | $self->{rbuf} = ""; |
1944 | |
2017 | |
1945 | Net::SSLeay::set_bio ($tls, $self->{_rbio}, $self->{_wbio}); |
2018 | Net::SSLeay::set_bio ($tls, $self->{_rbio}, $self->{_wbio}); |
1946 | |
2019 | |
1947 | $self->{_on_starttls} = sub { $_[0]{on_starttls}(@_) } |
2020 | $self->{_on_starttls} = sub { $_[0]{on_starttls}(@_) } |
1948 | if $self->{on_starttls}; |
2021 | if $self->{on_starttls}; |
… | |
… | |
1986 | if $self->{tls} > 0; |
2059 | if $self->{tls} > 0; |
1987 | |
2060 | |
1988 | delete @$self{qw(_rbio _wbio _tls_wbuf _on_starttls)}; |
2061 | delete @$self{qw(_rbio _wbio _tls_wbuf _on_starttls)}; |
1989 | } |
2062 | } |
1990 | |
2063 | |
|
|
2064 | =item $handle->resettls |
|
|
2065 | |
|
|
2066 | This rarely-used method simply resets and TLS state on the handle, usually |
|
|
2067 | causing data loss. |
|
|
2068 | |
|
|
2069 | One case where it may be useful is when you want to skip over the data in |
|
|
2070 | the stream but you are not interested in interpreting it, so data loss is |
|
|
2071 | no concern. |
|
|
2072 | |
|
|
2073 | =cut |
|
|
2074 | |
|
|
2075 | *resettls = \&_freetls; |
|
|
2076 | |
1991 | sub DESTROY { |
2077 | sub DESTROY { |
1992 | my ($self) = @_; |
2078 | my ($self) = @_; |
1993 | |
2079 | |
1994 | &_freetls; |
2080 | &_freetls; |
1995 | |
2081 | |
… | |
… | |
2004 | push @linger, AE::io $fh, 1, sub { |
2090 | push @linger, AE::io $fh, 1, sub { |
2005 | my $len = syswrite $fh, $wbuf, length $wbuf; |
2091 | my $len = syswrite $fh, $wbuf, length $wbuf; |
2006 | |
2092 | |
2007 | if ($len > 0) { |
2093 | if ($len > 0) { |
2008 | substr $wbuf, 0, $len, ""; |
2094 | substr $wbuf, 0, $len, ""; |
2009 | } else { |
2095 | } elsif (defined $len || ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK)) { |
2010 | @linger = (); # end |
2096 | @linger = (); # end |
2011 | } |
2097 | } |
2012 | }; |
2098 | }; |
2013 | push @linger, AE::timer $linger, 0, sub { |
2099 | push @linger, AE::timer $linger, 0, sub { |
2014 | @linger = (); |
2100 | @linger = (); |
… | |
… | |
2110 | |
2196 | |
2111 | It is only safe to "forget" the reference inside EOF or error callbacks, |
2197 | It is only safe to "forget" the reference inside EOF or error callbacks, |
2112 | from within all other callbacks, you need to explicitly call the C<< |
2198 | from within all other callbacks, you need to explicitly call the C<< |
2113 | ->destroy >> method. |
2199 | ->destroy >> method. |
2114 | |
2200 | |
|
|
2201 | =item Why is my C<on_eof> callback never called? |
|
|
2202 | |
|
|
2203 | Probably because your C<on_error> callback is being called instead: When |
|
|
2204 | you have outstanding requests in your read queue, then an EOF is |
|
|
2205 | considered an error as you clearly expected some data. |
|
|
2206 | |
|
|
2207 | To avoid this, make sure you have an empty read queue whenever your handle |
|
|
2208 | is supposed to be "idle" (i.e. connection closes are O.K.). You cna set |
|
|
2209 | an C<on_read> handler that simply pushes the first read requests in the |
|
|
2210 | queue. |
|
|
2211 | |
|
|
2212 | See also the next question, which explains this in a bit more detail. |
|
|
2213 | |
|
|
2214 | =item How can I serve requests in a loop? |
|
|
2215 | |
|
|
2216 | Most protocols consist of some setup phase (authentication for example) |
|
|
2217 | followed by a request handling phase, where the server waits for requests |
|
|
2218 | and handles them, in a loop. |
|
|
2219 | |
|
|
2220 | There are two important variants: The first (traditional, better) variant |
|
|
2221 | handles requests until the server gets some QUIT command, causing it to |
|
|
2222 | close the connection first (highly desirable for a busy TCP server). A |
|
|
2223 | client dropping the connection is an error, which means this variant can |
|
|
2224 | detect an unexpected detection close. |
|
|
2225 | |
|
|
2226 | To handle this case, always make sure you have a on-empty read queue, by |
|
|
2227 | pushing the "read request start" handler on it: |
|
|
2228 | |
|
|
2229 | # we assume a request starts with a single line |
|
|
2230 | my @start_request; @start_request = (line => sub { |
|
|
2231 | my ($hdl, $line) = @_; |
|
|
2232 | |
|
|
2233 | ... handle request |
|
|
2234 | |
|
|
2235 | # push next request read, possibly from a nested callback |
|
|
2236 | $hdl->push_read (@start_request); |
|
|
2237 | }); |
|
|
2238 | |
|
|
2239 | # auth done, now go into request handling loop |
|
|
2240 | # now push the first @start_request |
|
|
2241 | $hdl->push_read (@start_request); |
|
|
2242 | |
|
|
2243 | By always having an outstanding C<push_read>, the handle always expects |
|
|
2244 | some data and raises the C<EPIPE> error when the connction is dropped |
|
|
2245 | unexpectedly. |
|
|
2246 | |
|
|
2247 | The second variant is a protocol where the client can drop the connection |
|
|
2248 | at any time. For TCP, this means that the server machine may run out of |
|
|
2249 | sockets easier, and in general, it means you cnanot distinguish a protocl |
|
|
2250 | failure/client crash from a normal connection close. Nevertheless, these |
|
|
2251 | kinds of protocols are common (and sometimes even the best solution to the |
|
|
2252 | problem). |
|
|
2253 | |
|
|
2254 | Having an outstanding read request at all times is possible if you ignore |
|
|
2255 | C<EPIPE> errors, but this doesn't help with when the client drops the |
|
|
2256 | connection during a request, which would still be an error. |
|
|
2257 | |
|
|
2258 | A better solution is to push the initial request read in an C<on_read> |
|
|
2259 | callback. This avoids an error, as when the server doesn't expect data |
|
|
2260 | (i.e. is idly waiting for the next request, an EOF will not raise an |
|
|
2261 | error, but simply result in an C<on_eof> callback. It is also a bit slower |
|
|
2262 | and simpler: |
|
|
2263 | |
|
|
2264 | # auth done, now go into request handling loop |
|
|
2265 | $hdl->on_read (sub { |
|
|
2266 | my ($hdl) = @_; |
|
|
2267 | |
|
|
2268 | # called each time we receive data but the read queue is empty |
|
|
2269 | # simply start read the request |
|
|
2270 | |
|
|
2271 | $hdl->push_read (line => sub { |
|
|
2272 | my ($hdl, $line) = @_; |
|
|
2273 | |
|
|
2274 | ... handle request |
|
|
2275 | |
|
|
2276 | # do nothing special when the request has been handled, just |
|
|
2277 | # let the request queue go empty. |
|
|
2278 | }); |
|
|
2279 | }); |
|
|
2280 | |
2115 | =item I get different callback invocations in TLS mode/Why can't I pause |
2281 | =item I get different callback invocations in TLS mode/Why can't I pause |
2116 | reading? |
2282 | reading? |
2117 | |
2283 | |
2118 | Unlike, say, TCP, TLS connections do not consist of two independent |
2284 | Unlike, say, TCP, TLS connections do not consist of two independent |
2119 | communication channels, one for each direction. Or put differently, the |
2285 | communication channels, one for each direction. Or put differently, the |
… | |
… | |
2139 | $handle->on_read (sub { }); |
2305 | $handle->on_read (sub { }); |
2140 | $handle->on_eof (undef); |
2306 | $handle->on_eof (undef); |
2141 | $handle->on_error (sub { |
2307 | $handle->on_error (sub { |
2142 | my $data = delete $_[0]{rbuf}; |
2308 | my $data = delete $_[0]{rbuf}; |
2143 | }); |
2309 | }); |
|
|
2310 | |
|
|
2311 | Note that this example removes the C<rbuf> member from the handle object, |
|
|
2312 | which is not normally allowed by the API. It is expressly permitted in |
|
|
2313 | this case only, as the handle object needs to be destroyed afterwards. |
2144 | |
2314 | |
2145 | The reason to use C<on_error> is that TCP connections, due to latencies |
2315 | The reason to use C<on_error> is that TCP connections, due to latencies |
2146 | and packets loss, might get closed quite violently with an error, when in |
2316 | and packets loss, might get closed quite violently with an error, when in |
2147 | fact all data has been received. |
2317 | fact all data has been received. |
2148 | |
2318 | |