… | |
… | |
14 | |
14 | |
15 | AnyEvent::Handle - non-blocking I/O on file handles via AnyEvent |
15 | AnyEvent::Handle - non-blocking I/O on file handles via AnyEvent |
16 | |
16 | |
17 | =cut |
17 | =cut |
18 | |
18 | |
19 | our $VERSION = 4.234; |
19 | our $VERSION = 4.3; |
20 | |
20 | |
21 | =head1 SYNOPSIS |
21 | =head1 SYNOPSIS |
22 | |
22 | |
23 | use AnyEvent; |
23 | use AnyEvent; |
24 | use AnyEvent::Handle; |
24 | use AnyEvent::Handle; |
… | |
… | |
59 | treatment of characters applies to this module as well. |
59 | treatment of characters applies to this module as well. |
60 | |
60 | |
61 | All callbacks will be invoked with the handle object as their first |
61 | All callbacks will be invoked with the handle object as their first |
62 | argument. |
62 | argument. |
63 | |
63 | |
|
|
64 | =head2 SIGPIPE is not handled by this module |
|
|
65 | |
|
|
66 | SIGPIPE is not handled by this module, so one of the practical |
|
|
67 | requirements of using it is to ignore SIGPIPE (C<$SIG{PIPE} = |
|
|
68 | 'IGNORE'>). At least, this is highly recommend in a networked program: If |
|
|
69 | you use AnyEvent::Handle in a filter program (like sort), exiting on |
|
|
70 | SIGPIPE is probably the right thing to do. |
|
|
71 | |
64 | =head1 METHODS |
72 | =head1 METHODS |
65 | |
73 | |
66 | =over 4 |
74 | =over 4 |
67 | |
75 | |
68 | =item B<new (%args)> |
76 | =item B<new (%args)> |
… | |
… | |
232 | write data and will install a watcher that will write this data to the |
240 | write data and will install a watcher that will write this data to the |
233 | socket. No errors will be reported (this mostly matches how the operating |
241 | socket. No errors will be reported (this mostly matches how the operating |
234 | system treats outstanding data at socket close time). |
242 | system treats outstanding data at socket close time). |
235 | |
243 | |
236 | This will not work for partial TLS data that could not be encoded |
244 | This will not work for partial TLS data that could not be encoded |
237 | yet. This data will be lost. |
245 | yet. This data will be lost. Calling the C<stoptls> method in time might |
|
|
246 | help. |
238 | |
247 | |
239 | =item tls => "accept" | "connect" | Net::SSLeay::SSL object |
248 | =item tls => "accept" | "connect" | Net::SSLeay::SSL object |
240 | |
249 | |
241 | When this parameter is given, it enables TLS (SSL) mode, that means |
250 | When this parameter is given, it enables TLS (SSL) mode, that means |
242 | AnyEvent will start a TLS handshake as soon as the conenction has been |
251 | AnyEvent will start a TLS handshake as soon as the conenction has been |
… | |
… | |
273 | texts. |
282 | texts. |
274 | |
283 | |
275 | Note that you are responsible to depend on the JSON module if you want to |
284 | Note that you are responsible to depend on the JSON module if you want to |
276 | use this functionality, as AnyEvent does not have a dependency itself. |
285 | use this functionality, as AnyEvent does not have a dependency itself. |
277 | |
286 | |
278 | =item filter_r => $cb |
|
|
279 | |
|
|
280 | =item filter_w => $cb |
|
|
281 | |
|
|
282 | These exist, but are undocumented at this time. (They are used internally |
|
|
283 | by the TLS code). |
|
|
284 | |
|
|
285 | =back |
287 | =back |
286 | |
288 | |
287 | =cut |
289 | =cut |
288 | |
290 | |
289 | sub new { |
291 | sub new { |
… | |
… | |
293 | |
295 | |
294 | $self->{fh} or Carp::croak "mandatory argument fh is missing"; |
296 | $self->{fh} or Carp::croak "mandatory argument fh is missing"; |
295 | |
297 | |
296 | AnyEvent::Util::fh_nonblocking $self->{fh}, 1; |
298 | AnyEvent::Util::fh_nonblocking $self->{fh}, 1; |
297 | |
299 | |
298 | if ($self->{tls}) { |
|
|
299 | require Net::SSLeay; |
|
|
300 | $self->starttls (delete $self->{tls}, delete $self->{tls_ctx}); |
300 | $self->starttls (delete $self->{tls}, delete $self->{tls_ctx}) |
301 | } |
301 | if $self->{tls}; |
302 | |
302 | |
303 | $self->{_activity} = AnyEvent->now; |
303 | $self->{_activity} = AnyEvent->now; |
304 | $self->_timeout; |
304 | $self->_timeout; |
305 | |
305 | |
306 | $self->on_drain (delete $self->{on_drain}) if exists $self->{on_drain}; |
306 | $self->on_drain (delete $self->{on_drain}) if exists $self->{on_drain}; |
… | |
… | |
318 | delete $self->{_tw}; |
318 | delete $self->{_tw}; |
319 | delete $self->{_rw}; |
319 | delete $self->{_rw}; |
320 | delete $self->{_ww}; |
320 | delete $self->{_ww}; |
321 | delete $self->{fh}; |
321 | delete $self->{fh}; |
322 | |
322 | |
323 | $self->stoptls; |
323 | &_freetls; |
324 | |
324 | |
325 | delete $self->{on_read}; |
325 | delete $self->{on_read}; |
326 | delete $self->{_queue}; |
326 | delete $self->{_queue}; |
327 | } |
327 | } |
328 | |
328 | |
… | |
… | |
487 | my ($self, $cb) = @_; |
487 | my ($self, $cb) = @_; |
488 | |
488 | |
489 | $self->{on_drain} = $cb; |
489 | $self->{on_drain} = $cb; |
490 | |
490 | |
491 | $cb->($self) |
491 | $cb->($self) |
492 | if $cb && $self->{low_water_mark} >= length $self->{wbuf}; |
492 | if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf}); |
493 | } |
493 | } |
494 | |
494 | |
495 | =item $handle->push_write ($data) |
495 | =item $handle->push_write ($data) |
496 | |
496 | |
497 | Queues the given scalar to be written. You can push as much data as you |
497 | Queues the given scalar to be written. You can push as much data as you |
… | |
… | |
514 | substr $self->{wbuf}, 0, $len, ""; |
514 | substr $self->{wbuf}, 0, $len, ""; |
515 | |
515 | |
516 | $self->{_activity} = AnyEvent->now; |
516 | $self->{_activity} = AnyEvent->now; |
517 | |
517 | |
518 | $self->{on_drain}($self) |
518 | $self->{on_drain}($self) |
519 | if $self->{low_water_mark} >= length $self->{wbuf} |
519 | if $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf}) |
520 | && $self->{on_drain}; |
520 | && $self->{on_drain}; |
521 | |
521 | |
522 | delete $self->{_ww} unless length $self->{wbuf}; |
522 | delete $self->{_ww} unless length $self->{wbuf}; |
523 | } elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) { |
523 | } elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) { |
524 | $self->_error ($!, 1); |
524 | $self->_error ($!, 1); |
… | |
… | |
548 | |
548 | |
549 | @_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write") |
549 | @_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write") |
550 | ->($self, @_); |
550 | ->($self, @_); |
551 | } |
551 | } |
552 | |
552 | |
553 | if ($self->{filter_w}) { |
553 | if ($self->{tls}) { |
554 | $self->{filter_w}($self, \$_[0]); |
554 | $self->{_tls_wbuf} .= $_[0]; |
|
|
555 | &_dotls ($self); |
555 | } else { |
556 | } else { |
556 | $self->{wbuf} .= $_[0]; |
557 | $self->{wbuf} .= $_[0]; |
557 | $self->_drain_wbuf; |
558 | $self->_drain_wbuf; |
558 | } |
559 | } |
559 | } |
560 | } |
… | |
… | |
576 | =cut |
577 | =cut |
577 | |
578 | |
578 | register_write_type netstring => sub { |
579 | register_write_type netstring => sub { |
579 | my ($self, $string) = @_; |
580 | my ($self, $string) = @_; |
580 | |
581 | |
581 | sprintf "%d:%s,", (length $string), $string |
582 | (length $string) . ":$string," |
582 | }; |
583 | }; |
583 | |
584 | |
584 | =item packstring => $format, $data |
585 | =item packstring => $format, $data |
585 | |
586 | |
586 | An octet string prefixed with an encoded length. The encoding C<$format> |
587 | An octet string prefixed with an encoded length. The encoding C<$format> |
… | |
… | |
795 | |
796 | |
796 | last; # more data might arrive |
797 | last; # more data might arrive |
797 | } |
798 | } |
798 | } else { |
799 | } else { |
799 | # read side becomes idle |
800 | # read side becomes idle |
800 | delete $self->{_rw}; |
801 | delete $self->{_rw} unless $self->{tls}; |
801 | last; |
802 | last; |
802 | } |
803 | } |
803 | } |
804 | } |
804 | |
805 | |
805 | if ($self->{_eof}) { |
806 | if ($self->{_eof}) { |
… | |
… | |
1100 | An octet string prefixed with an encoded length. The encoding C<$format> |
1101 | An octet string prefixed with an encoded length. The encoding C<$format> |
1101 | uses the same format as a Perl C<pack> format, but must specify a single |
1102 | uses the same format as a Perl C<pack> format, but must specify a single |
1102 | integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an |
1103 | integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an |
1103 | optional C<!>, C<< < >> or C<< > >> modifier). |
1104 | optional C<!>, C<< < >> or C<< > >> modifier). |
1104 | |
1105 | |
1105 | DNS over TCP uses a prefix of C<n>, EPP uses a prefix of C<N>. |
1106 | For example, DNS over TCP uses a prefix of C<n> (2 octet network order), |
|
|
1107 | EPP uses a prefix of C<N> (4 octtes). |
1106 | |
1108 | |
1107 | Example: read a block of data prefixed by its length in BER-encoded |
1109 | Example: read a block of data prefixed by its length in BER-encoded |
1108 | format (very efficient). |
1110 | format (very efficient). |
1109 | |
1111 | |
1110 | $handle->push_read (packstring => "w", sub { |
1112 | $handle->push_read (packstring => "w", sub { |
… | |
… | |
1263 | Note that AnyEvent::Handle will automatically C<start_read> for you when |
1265 | Note that AnyEvent::Handle will automatically C<start_read> for you when |
1264 | you change the C<on_read> callback or push/unshift a read callback, and it |
1266 | you change the C<on_read> callback or push/unshift a read callback, and it |
1265 | will automatically C<stop_read> for you when neither C<on_read> is set nor |
1267 | will automatically C<stop_read> for you when neither C<on_read> is set nor |
1266 | there are any read requests in the queue. |
1268 | there are any read requests in the queue. |
1267 | |
1269 | |
|
|
1270 | These methods will have no effect when in TLS mode (as TLS doesn't support |
|
|
1271 | half-duplex connections). |
|
|
1272 | |
1268 | =cut |
1273 | =cut |
1269 | |
1274 | |
1270 | sub stop_read { |
1275 | sub stop_read { |
1271 | my ($self) = @_; |
1276 | my ($self) = @_; |
1272 | |
1277 | |
1273 | delete $self->{_rw}; |
1278 | delete $self->{_rw} unless $self->{tls}; |
1274 | } |
1279 | } |
1275 | |
1280 | |
1276 | sub start_read { |
1281 | sub start_read { |
1277 | my ($self) = @_; |
1282 | my ($self) = @_; |
1278 | |
1283 | |
1279 | unless ($self->{_rw} || $self->{_eof}) { |
1284 | unless ($self->{_rw} || $self->{_eof}) { |
1280 | Scalar::Util::weaken $self; |
1285 | Scalar::Util::weaken $self; |
1281 | |
1286 | |
1282 | $self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub { |
1287 | $self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub { |
1283 | my $rbuf = $self->{filter_r} ? \my $buf : \$self->{rbuf}; |
1288 | my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf}); |
1284 | my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf; |
1289 | my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf; |
1285 | |
1290 | |
1286 | if ($len > 0) { |
1291 | if ($len > 0) { |
1287 | $self->{_activity} = AnyEvent->now; |
1292 | $self->{_activity} = AnyEvent->now; |
1288 | |
1293 | |
1289 | $self->{filter_r} |
1294 | if ($self->{tls}) { |
1290 | ? $self->{filter_r}($self, $rbuf) |
1295 | Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf); |
1291 | : $self->{_in_drain} || $self->_drain_rbuf; |
1296 | &_dotls ($self); |
|
|
1297 | } else { |
|
|
1298 | $self->_drain_rbuf unless $self->{_in_drain}; |
|
|
1299 | } |
1292 | |
1300 | |
1293 | } elsif (defined $len) { |
1301 | } elsif (defined $len) { |
1294 | delete $self->{_rw}; |
1302 | delete $self->{_rw}; |
1295 | $self->{_eof} = 1; |
1303 | $self->{_eof} = 1; |
1296 | $self->_drain_rbuf unless $self->{_in_drain}; |
1304 | $self->_drain_rbuf unless $self->{_in_drain}; |
… | |
… | |
1311 | while ((my $len = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) { |
1319 | while ((my $len = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) { |
1312 | substr $self->{_tls_wbuf}, 0, $len, ""; |
1320 | substr $self->{_tls_wbuf}, 0, $len, ""; |
1313 | } |
1321 | } |
1314 | } |
1322 | } |
1315 | |
1323 | |
1316 | if (length ($buf = Net::SSLeay::BIO_read ($self->{_wbio}))) { |
|
|
1317 | $self->{wbuf} .= $buf; |
|
|
1318 | $self->_drain_wbuf; |
|
|
1319 | } |
|
|
1320 | |
|
|
1321 | while (defined ($buf = Net::SSLeay::read ($self->{tls}))) { |
1324 | while (defined ($buf = Net::SSLeay::read ($self->{tls}))) { |
1322 | if (length $buf) { |
1325 | unless (length $buf) { |
1323 | $self->{rbuf} .= $buf; |
|
|
1324 | $self->_drain_rbuf unless $self->{_in_drain}; |
|
|
1325 | } else { |
|
|
1326 | # let's treat SSL-eof as we treat normal EOF |
1326 | # let's treat SSL-eof as we treat normal EOF |
|
|
1327 | delete $self->{_rw}; |
1327 | $self->{_eof} = 1; |
1328 | $self->{_eof} = 1; |
1328 | $self->_shutdown; |
1329 | &_freetls; |
1329 | return; |
|
|
1330 | } |
1330 | } |
|
|
1331 | |
|
|
1332 | $self->{rbuf} .= $buf; |
|
|
1333 | $self->_drain_rbuf unless $self->{_in_drain}; |
|
|
1334 | $self->{tls} or return; # tls session might have gone away in callback |
1331 | } |
1335 | } |
1332 | |
1336 | |
1333 | my $err = Net::SSLeay::get_error ($self->{tls}, -1); |
1337 | my $err = Net::SSLeay::get_error ($self->{tls}, -1); |
1334 | |
1338 | |
1335 | if ($err!= Net::SSLeay::ERROR_WANT_READ ()) { |
1339 | if ($err!= Net::SSLeay::ERROR_WANT_READ ()) { |
… | |
… | |
1339 | return $self->_error (&Errno::EIO, 1); |
1343 | return $self->_error (&Errno::EIO, 1); |
1340 | } |
1344 | } |
1341 | |
1345 | |
1342 | # all others are fine for our purposes |
1346 | # all others are fine for our purposes |
1343 | } |
1347 | } |
|
|
1348 | |
|
|
1349 | while (length ($buf = Net::SSLeay::BIO_read ($self->{_wbio}))) { |
|
|
1350 | $self->{wbuf} .= $buf; |
|
|
1351 | $self->_drain_wbuf; |
|
|
1352 | } |
1344 | } |
1353 | } |
1345 | |
1354 | |
1346 | =item $handle->starttls ($tls[, $tls_ctx]) |
1355 | =item $handle->starttls ($tls[, $tls_ctx]) |
1347 | |
1356 | |
1348 | Instead of starting TLS negotiation immediately when the AnyEvent::Handle |
1357 | Instead of starting TLS negotiation immediately when the AnyEvent::Handle |
… | |
… | |
1357 | |
1366 | |
1358 | The TLS connection object will end up in C<< $handle->{tls} >> after this |
1367 | The TLS connection object will end up in C<< $handle->{tls} >> after this |
1359 | call and can be used or changed to your liking. Note that the handshake |
1368 | call and can be used or changed to your liking. Note that the handshake |
1360 | might have already started when this function returns. |
1369 | might have already started when this function returns. |
1361 | |
1370 | |
|
|
1371 | If it an error to start a TLS handshake more than once per |
|
|
1372 | AnyEvent::Handle object (this is due to bugs in OpenSSL). |
|
|
1373 | |
1362 | =cut |
1374 | =cut |
1363 | |
1375 | |
1364 | sub starttls { |
1376 | sub starttls { |
1365 | my ($self, $ssl, $ctx) = @_; |
1377 | my ($self, $ssl, $ctx) = @_; |
1366 | |
1378 | |
1367 | $self->stoptls; |
1379 | require Net::SSLeay; |
1368 | |
1380 | |
|
|
1381 | Carp::croak "it is an error to call starttls more than once on an Anyevent::Handle object" |
|
|
1382 | if $self->{tls}; |
|
|
1383 | |
1369 | if ($ssl eq "accept") { |
1384 | if ($ssl eq "accept") { |
1370 | $ssl = Net::SSLeay::new ($ctx || TLS_CTX ()); |
1385 | $ssl = Net::SSLeay::new ($ctx || TLS_CTX ()); |
1371 | Net::SSLeay::set_accept_state ($ssl); |
1386 | Net::SSLeay::set_accept_state ($ssl); |
1372 | } elsif ($ssl eq "connect") { |
1387 | } elsif ($ssl eq "connect") { |
1373 | $ssl = Net::SSLeay::new ($ctx || TLS_CTX ()); |
1388 | $ssl = Net::SSLeay::new ($ctx || TLS_CTX ()); |
… | |
… | |
1382 | # and mismaintained ssleay-module doesn't even offer them). |
1397 | # and mismaintained ssleay-module doesn't even offer them). |
1383 | # http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html |
1398 | # http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html |
1384 | # |
1399 | # |
1385 | # in short: this is a mess. |
1400 | # in short: this is a mess. |
1386 | # |
1401 | # |
1387 | # note that we do not try to kepe the length constant between writes as we are required to do. |
1402 | # note that we do not try to keep the length constant between writes as we are required to do. |
1388 | # we assume that most (but not all) of this insanity only applies to non-blocking cases, |
1403 | # we assume that most (but not all) of this insanity only applies to non-blocking cases, |
1389 | # and we drive openssl fully in blocking mode here. |
1404 | # and we drive openssl fully in blocking mode here. Or maybe we don't - openssl seems to |
|
|
1405 | # have identity issues in that area. |
1390 | Net::SSLeay::CTX_set_mode ($self->{tls}, |
1406 | Net::SSLeay::CTX_set_mode ($self->{tls}, |
1391 | (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1) |
1407 | (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1) |
1392 | | (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2)); |
1408 | | (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2)); |
1393 | |
1409 | |
1394 | $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); |
1410 | $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); |
1395 | $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); |
1411 | $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); |
1396 | |
1412 | |
1397 | Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio}); |
1413 | Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio}); |
1398 | |
1414 | |
1399 | $self->{filter_w} = sub { |
1415 | &_dotls; # need to trigger the initial handshake |
1400 | $_[0]{_tls_wbuf} .= ${$_[1]}; |
1416 | $self->start_read; # make sure we actually do read |
1401 | &_dotls; |
|
|
1402 | }; |
|
|
1403 | $self->{filter_r} = sub { |
|
|
1404 | Net::SSLeay::BIO_write ($_[0]{_rbio}, ${$_[1]}); |
|
|
1405 | &_dotls; |
|
|
1406 | }; |
|
|
1407 | } |
1417 | } |
1408 | |
1418 | |
1409 | =item $handle->stoptls |
1419 | =item $handle->stoptls |
1410 | |
1420 | |
1411 | Destroys the SSL connection, if any. Partial read or write data will be |
1421 | Shuts down the SSL connection - this makes a proper EOF handshake by |
1412 | lost. |
1422 | sending a close notify to the other side, but since OpenSSL doesn't |
|
|
1423 | support non-blocking shut downs, it is not possible to re-use the stream |
|
|
1424 | afterwards. |
1413 | |
1425 | |
1414 | =cut |
1426 | =cut |
1415 | |
1427 | |
1416 | sub stoptls { |
1428 | sub stoptls { |
1417 | my ($self) = @_; |
1429 | my ($self) = @_; |
1418 | |
1430 | |
|
|
1431 | if ($self->{tls}) { |
|
|
1432 | Net::SSLeay::shutdown ($self->{tls}); |
|
|
1433 | |
|
|
1434 | &_dotls; |
|
|
1435 | |
|
|
1436 | # we don't give a shit. no, we do, but we can't. no... |
|
|
1437 | # we, we... have to use openssl :/ |
|
|
1438 | &_freetls; |
|
|
1439 | } |
|
|
1440 | } |
|
|
1441 | |
|
|
1442 | sub _freetls { |
|
|
1443 | my ($self) = @_; |
|
|
1444 | |
|
|
1445 | return unless $self->{tls}; |
|
|
1446 | |
1419 | Net::SSLeay::free (delete $self->{tls}) if $self->{tls}; |
1447 | Net::SSLeay::free (delete $self->{tls}); |
1420 | |
1448 | |
1421 | delete $self->{_rbio}; |
1449 | delete @$self{qw(_rbio _wbio _tls_wbuf)}; |
1422 | delete $self->{_wbio}; |
|
|
1423 | delete $self->{_tls_wbuf}; |
|
|
1424 | delete $self->{filter_r}; |
|
|
1425 | delete $self->{filter_w}; |
|
|
1426 | } |
1450 | } |
1427 | |
1451 | |
1428 | sub DESTROY { |
1452 | sub DESTROY { |
1429 | my $self = shift; |
1453 | my $self = shift; |
1430 | |
1454 | |
1431 | $self->stoptls; |
1455 | &_freetls; |
1432 | |
1456 | |
1433 | my $linger = exists $self->{linger} ? $self->{linger} : 3600; |
1457 | my $linger = exists $self->{linger} ? $self->{linger} : 3600; |
1434 | |
1458 | |
1435 | if ($linger && length $self->{wbuf}) { |
1459 | if ($linger && length $self->{wbuf}) { |
1436 | my $fh = delete $self->{fh}; |
1460 | my $fh = delete $self->{fh}; |
… | |
… | |
1488 | } |
1512 | } |
1489 | } |
1513 | } |
1490 | |
1514 | |
1491 | =back |
1515 | =back |
1492 | |
1516 | |
|
|
1517 | |
|
|
1518 | =head1 NONFREQUENTLY ASKED QUESTIONS |
|
|
1519 | |
|
|
1520 | =over 4 |
|
|
1521 | |
|
|
1522 | =item How do I read data until the other side closes the connection? |
|
|
1523 | |
|
|
1524 | If you just want to read your data into a perl scalar, the easiest way |
|
|
1525 | to achieve this is by setting an C<on_read> callback that does nothing, |
|
|
1526 | clearing the C<on_eof> callback and in the C<on_error> callback, the data |
|
|
1527 | will be in C<$_[0]{rbuf}>: |
|
|
1528 | |
|
|
1529 | $handle->on_read (sub { }); |
|
|
1530 | $handle->on_eof (undef); |
|
|
1531 | $handle->on_error (sub { |
|
|
1532 | my $data = delete $_[0]{rbuf}; |
|
|
1533 | undef $handle; |
|
|
1534 | }); |
|
|
1535 | |
|
|
1536 | The reason to use C<on_error> is that TCP connections, due to latencies |
|
|
1537 | and packets loss, might get closed quite violently with an error, when in |
|
|
1538 | fact, all data has been received. |
|
|
1539 | |
|
|
1540 | It is usually better to use acknowledgements when transfering data, |
|
|
1541 | to make sure the other side hasn't just died and you got the data |
|
|
1542 | intact. This is also one reason why so many internet protocols have an |
|
|
1543 | explicit QUIT command. |
|
|
1544 | |
|
|
1545 | |
|
|
1546 | =item I don't want to destroy the handle too early - how do I wait until |
|
|
1547 | all data has been written? |
|
|
1548 | |
|
|
1549 | After writing your last bits of data, set the C<on_drain> callback |
|
|
1550 | and destroy the handle in there - with the default setting of |
|
|
1551 | C<low_water_mark> this will be called precisely when all data has been |
|
|
1552 | written to the socket: |
|
|
1553 | |
|
|
1554 | $handle->push_write (...); |
|
|
1555 | $handle->on_drain (sub { |
|
|
1556 | warn "all data submitted to the kernel\n"; |
|
|
1557 | undef $handle; |
|
|
1558 | }); |
|
|
1559 | |
|
|
1560 | =back |
|
|
1561 | |
|
|
1562 | |
1493 | =head1 SUBCLASSING AnyEvent::Handle |
1563 | =head1 SUBCLASSING AnyEvent::Handle |
1494 | |
1564 | |
1495 | In many cases, you might want to subclass AnyEvent::Handle. |
1565 | In many cases, you might want to subclass AnyEvent::Handle. |
1496 | |
1566 | |
1497 | To make this easier, a given version of AnyEvent::Handle uses these |
1567 | To make this easier, a given version of AnyEvent::Handle uses these |