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Revision 1.197 by root, Tue Aug 31 00:59:55 2010 UTC vs.
Revision 1.229 by root, Mon Feb 27 17:14:02 2012 UTC

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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 => "got error $msg\n";
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 $cv->recv;
32 32
33=head1 DESCRIPTION 33=head1 DESCRIPTION
34 34
35This module is a helper module to make it easier to do event-based I/O on 35This is a helper module to make it easier to do event-based I/O on
36stream-based filehandles (sockets, pipes or other stream things). 36stream-based filehandles (sockets, pipes, and other stream things).
37 37
38The L<AnyEvent::Intro> tutorial contains some well-documented 38The L<AnyEvent::Intro> tutorial contains some well-documented
39AnyEvent::Handle examples. 39AnyEvent::Handle examples.
40 40
41In the following, when the documentation refers to of "bytes" then this 41In the following, where the documentation refers to "bytes", it means
42means characters. As sysread and syswrite are used for all I/O, their 42characters. As sysread and syswrite are used for all I/O, their
43treatment of characters applies to this module as well. 43treatment of characters applies to this module as well.
44 44
45At the very minimum, you should specify C<fh> or C<connect>, and the 45At the very minimum, you should specify C<fh> or C<connect>, and the
46C<on_error> callback. 46C<on_error> callback.
47 47
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75 } 75 }
76 76
77 \&$func 77 \&$func
78} 78}
79 79
80sub 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...
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112=over 4 114=over 4
113 115
114=item on_prepare => $cb->($handle) 116=item on_prepare => $cb->($handle)
115 117
116This (rarely used) callback is called before a new connection is 118This (rarely used) callback is called before a new connection is
117attempted, 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
118prepare the file handle with parameters required for the actual connect 121file 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 122settings that can be changed when the connection is already established).
120established).
121 123
122The 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
123seconds (or C<0>, or C<undef>, or the empty list, to indicate the default 125seconds (or C<0>, or C<undef>, or the empty list, to indicate that the
124timeout is to be used). 126default timeout is to be used).
125 127
126=item on_connect => $cb->($handle, $host, $port, $retry->()) 128=item on_connect => $cb->($handle, $host, $port, $retry->())
127 129
128This callback is called when a connection has been successfully established. 130This callback is called when a connection has been successfully established.
129 131
130The actual numeric host and port (the socket peername) are passed as 132The peer's numeric host and port (the socket peername) are passed as
131parameters, together with a retry callback. 133parameters, together with a retry callback. At the time it is called the
134read and write queues, EOF status, TLS status and similar properties of
135the handle will have been reset.
132 136
137It is not allowed to use the read or write queues while the handle object
138is connecting.
139
133When, for some reason, the handle is not acceptable, then calling 140If, for some reason, the handle is not acceptable, calling C<$retry> will
134C<$retry> will continue with the next connection target (in case of 141continue with the next connection target (in case of multi-homed hosts or
135multi-homed hosts or SRV records there can be multiple connection 142SRV records there can be multiple connection endpoints). The C<$retry>
136endpoints). At the time it is called the read and write queues, eof 143callback can be invoked after the connect callback returns, i.e. one can
137status, tls status and similar properties of the handle will have been 144start a handshake and then decide to retry with the next host if the
138reset. 145handshake fails.
139 146
140In most cases, ignoring the C<$retry> parameter is the way to go. 147In most cases, you should ignore the C<$retry> parameter.
141 148
142=item on_connect_error => $cb->($handle, $message) 149=item on_connect_error => $cb->($handle, $message)
143 150
144This callback is called when the connection could not be 151This callback is called when the connection could not be
145established. C<$!> will contain the relevant error code, and C<$message> a 152established. C<$!> will contain the relevant error code, and C<$message> a
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152 159
153=item on_error => $cb->($handle, $fatal, $message) 160=item on_error => $cb->($handle, $fatal, $message)
154 161
155This is the error callback, which is called when, well, some error 162This is the error callback, which is called when, well, some error
156occured, such as not being able to resolve the hostname, failure to 163occured, such as not being able to resolve the hostname, failure to
157connect or a read error. 164connect, or a read error.
158 165
159Some errors are fatal (which is indicated by C<$fatal> being true). On 166Some errors are fatal (which is indicated by C<$fatal> being true). On
160fatal errors the handle object will be destroyed (by a call to C<< -> 167fatal errors the handle object will be destroyed (by a call to C<< ->
161destroy >>) after invoking the error callback (which means you are free to 168destroy >>) after invoking the error callback (which means you are free to
162examine the handle object). Examples of fatal errors are an EOF condition 169examine the handle object). Examples of fatal errors are an EOF condition
163with active (but unsatisifable) read watchers (C<EPIPE>) or I/O errors. In 170with active (but unsatisfiable) read watchers (C<EPIPE>) or I/O errors. In
164cases where the other side can close the connection at their will it is 171cases where the other side can close the connection at will, it is
165often easiest to not report C<EPIPE> errors in this callback. 172often easiest to not report C<EPIPE> errors in this callback.
166 173
167AnyEvent::Handle tries to find an appropriate error code for you to check 174AnyEvent::Handle tries to find an appropriate error code for you to check
168against, but in some cases (TLS errors), this does not work well. It is 175against, but in some cases (TLS errors), this does not work well. It is
169recommended to always output the C<$message> argument in human-readable 176recommended to always output the C<$message> argument in human-readable
170error messages (it's usually the same as C<"$!">). 177error messages (it's usually the same as C<"$!">).
171 178
172Non-fatal errors can be retried by simply returning, but it is recommended 179Non-fatal errors can be retried by returning, but it is recommended
173to simply ignore this parameter and instead abondon the handle object 180to simply ignore this parameter and instead abondon the handle object
174when this callback is invoked. Examples of non-fatal errors are timeouts 181when this callback is invoked. Examples of non-fatal errors are timeouts
175C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>). 182C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>).
176 183
177On callback entrance, the value of C<$!> contains the operating system 184On entry to the callback, the value of C<$!> contains the operating
178error code (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT>, C<EBADMSG> or 185system error code (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT>, C<EBADMSG> or
179C<EPROTO>). 186C<EPROTO>).
180 187
181While not mandatory, it is I<highly> recommended to set this callback, as 188While not mandatory, it is I<highly> recommended to set this callback, as
182you will not be notified of errors otherwise. The default simply calls 189you will not be notified of errors otherwise. The default just calls
183C<croak>. 190C<croak>.
184 191
185=item on_read => $cb->($handle) 192=item on_read => $cb->($handle)
186 193
187This sets the default read callback, which is called when data arrives 194This sets the default read callback, which is called when data arrives
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195the beginning from it. 202the beginning from it.
196 203
197You can also call C<< ->push_read (...) >> or any other function that 204You can also call C<< ->push_read (...) >> or any other function that
198modifies the read queue. Or do both. Or ... 205modifies the read queue. Or do both. Or ...
199 206
200When an EOF condition is detected then AnyEvent::Handle will first try to 207When an EOF condition is detected, AnyEvent::Handle will first try to
201feed all the remaining data to the queued callbacks and C<on_read> before 208feed all the remaining data to the queued callbacks and C<on_read> before
202calling the C<on_eof> callback. If no progress can be made, then a fatal 209calling the C<on_eof> callback. If no progress can be made, then a fatal
203error will be raised (with C<$!> set to C<EPIPE>). 210error will be raised (with C<$!> set to C<EPIPE>).
204 211
205Note that, unlike requests in the read queue, an C<on_read> callback 212Note that, unlike requests in the read queue, an C<on_read> callback
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223If an EOF condition has been detected but no C<on_eof> callback has been 230If an EOF condition has been detected but no C<on_eof> callback has been
224set, then a fatal error will be raised with C<$!> set to <0>. 231set, then a fatal error will be raised with C<$!> set to <0>.
225 232
226=item on_drain => $cb->($handle) 233=item on_drain => $cb->($handle)
227 234
228This sets the callback that is called when the write buffer becomes empty 235This sets the callback that is called once when the write buffer becomes
229(or when the callback is set and the buffer is empty already). 236empty (and immediately when the handle object is created).
230 237
231To append to the write buffer, use the C<< ->push_write >> method. 238To append to the write buffer, use the C<< ->push_write >> method.
232 239
233This callback is useful when you don't want to put all of your write data 240This callback is useful when you don't want to put all of your write data
234into the queue at once, for example, when you want to write the contents 241into the queue at once, for example, when you want to write the contents
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246many seconds pass without a successful read or write on the underlying 253many seconds pass without a successful read or write on the underlying
247file handle (or a call to C<timeout_reset>), the C<on_timeout> callback 254file handle (or a call to C<timeout_reset>), the C<on_timeout> callback
248will be invoked (and if that one is missing, a non-fatal C<ETIMEDOUT> 255will be invoked (and if that one is missing, a non-fatal C<ETIMEDOUT>
249error will be raised). 256error will be raised).
250 257
251There are three variants of the timeouts that work fully independent 258There are three variants of the timeouts that work independently of each
252of each other, for both read and write, just read, and just write: 259other, for both read and write (triggered when nothing was read I<OR>
260written), just read (triggered when nothing was read), and just write:
253C<timeout>, C<rtimeout> and C<wtimeout>, with corresponding callbacks 261C<timeout>, C<rtimeout> and C<wtimeout>, with corresponding callbacks
254C<on_timeout>, C<on_rtimeout> and C<on_wtimeout>, and reset functions 262C<on_timeout>, C<on_rtimeout> and C<on_wtimeout>, and reset functions
255C<timeout_reset>, C<rtimeout_reset>, and C<wtimeout_reset>. 263C<timeout_reset>, C<rtimeout_reset>, and C<wtimeout_reset>.
256 264
257Note that timeout processing is also active when you currently do not have 265Note that timeout processing is active even when you do not have any
258any outstanding read or write requests: If you plan to keep the connection 266outstanding read or write requests: If you plan to keep the connection
259idle then you should disable the timout temporarily or ignore the timeout 267idle then you should disable the timeout temporarily or ignore the
260in the C<on_timeout> callback, in which case AnyEvent::Handle will simply 268timeout in the corresponding C<on_timeout> callback, in which case
261restart the timeout. 269AnyEvent::Handle will simply restart the timeout.
262 270
263Zero (the default) disables this timeout. 271Zero (the default) disables the corresponding timeout.
264 272
265=item on_timeout => $cb->($handle) 273=item on_timeout => $cb->($handle)
274
275=item on_rtimeout => $cb->($handle)
276
277=item on_wtimeout => $cb->($handle)
266 278
267Called whenever the inactivity timeout passes. If you return from this 279Called whenever the inactivity timeout passes. If you return from this
268callback, then the timeout will be reset as if some activity had happened, 280callback, then the timeout will be reset as if some activity had happened,
269so this condition is not fatal in any way. 281so this condition is not fatal in any way.
270 282
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278be configured to accept only so-and-so much data that it cannot act on 290be configured to accept only so-and-so much data that it cannot act on
279(for example, when expecting a line, an attacker could send an unlimited 291(for example, when expecting a line, an attacker could send an unlimited
280amount of data without a callback ever being called as long as the line 292amount of data without a callback ever being called as long as the line
281isn't finished). 293isn't finished).
282 294
295=item wbuf_max => <bytes>
296
297If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)
298when the write buffer ever (strictly) exceeds this size. This is useful to
299avoid some forms of denial-of-service attacks.
300
301Although the units of this parameter is bytes, this is the I<raw> number
302of bytes not yet accepted by the kernel. This can make a difference when
303you e.g. use TLS, as TLS typically makes your write data larger (but it
304can also make it smaller due to compression).
305
306As an example of when this limit is useful, take a chat server that sends
307chat messages to a client. If the client does not read those in a timely
308manner then the send buffer in the server would grow unbounded.
309
283=item autocork => <boolean> 310=item autocork => <boolean>
284 311
285When disabled (the default), then C<push_write> will try to immediately 312When disabled (the default), C<push_write> will try to immediately
286write the data to the handle, if possible. This avoids having to register 313write the data to the handle if possible. This avoids having to register
287a write watcher and wait for the next event loop iteration, but can 314a write watcher and wait for the next event loop iteration, but can
288be inefficient if you write multiple small chunks (on the wire, this 315be inefficient if you write multiple small chunks (on the wire, this
289disadvantage is usually avoided by your kernel's nagle algorithm, see 316disadvantage is usually avoided by your kernel's nagle algorithm, see
290C<no_delay>, but this option can save costly syscalls). 317C<no_delay>, but this option can save costly syscalls).
291 318
292When enabled, then writes will always be queued till the next event loop 319When enabled, writes will always be queued till the next event loop
293iteration. This is efficient when you do many small writes per iteration, 320iteration. This is efficient when you do many small writes per iteration,
294but less efficient when you do a single write only per iteration (or when 321but less efficient when you do a single write only per iteration (or when
295the write buffer often is full). It also increases write latency. 322the write buffer often is full). It also increases write latency.
296 323
297=item no_delay => <boolean> 324=item no_delay => <boolean>
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301the Nagle algorithm, and usually it is beneficial. 328the Nagle algorithm, and usually it is beneficial.
302 329
303In some situations you want as low a delay as possible, which can be 330In some situations you want as low a delay as possible, which can be
304accomplishd by setting this option to a true value. 331accomplishd by setting this option to a true value.
305 332
306The default is your opertaing system's default behaviour (most likely 333The default is your operating system's default behaviour (most likely
307enabled), this option explicitly enables or disables it, if possible. 334enabled). This option explicitly enables or disables it, if possible.
308 335
309=item keepalive => <boolean> 336=item keepalive => <boolean>
310 337
311Enables (default disable) the SO_KEEPALIVE option on the stream socket: 338Enables (default disable) the SO_KEEPALIVE option on the stream socket:
312normally, TCP connections have no time-out once established, so TCP 339normally, TCP connections have no time-out once established, so TCP
313connections, once established, can stay alive forever even when the other 340connections, once established, can stay alive forever even when the other
314side has long gone. TCP keepalives are a cheap way to take down long-lived 341side has long gone. TCP keepalives are a cheap way to take down long-lived
315TCP connections whent he other side becomes unreachable. While the default 342TCP connections when the other side becomes unreachable. While the default
316is OS-dependent, TCP keepalives usually kick in after around two hours, 343is OS-dependent, TCP keepalives usually kick in after around two hours,
317and, if the other side doesn't reply, take down the TCP connection some 10 344and, if the other side doesn't reply, take down the TCP connection some 10
318to 15 minutes later. 345to 15 minutes later.
319 346
320It is harmless to specify this option for file handles that do not support 347It is harmless to specify this option for file handles that do not support
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338already have occured on BSD systems), but at least it will protect you 365already have occured on BSD systems), but at least it will protect you
339from most attacks. 366from most attacks.
340 367
341=item read_size => <bytes> 368=item read_size => <bytes>
342 369
343The default read block size (the amount of bytes this module will 370The initial read block size, the number of bytes this module will try
344try to read during each loop iteration, which affects memory 371to read during each loop iteration. Each handle object will consume
345requirements). Default: C<8192>. 372at least this amount of memory for the read buffer as well, so when
373handling many connections watch out for memory requirements). See also
374C<max_read_size>. Default: C<2048>.
375
376=item max_read_size => <bytes>
377
378The maximum read buffer size used by the dynamic adjustment
379algorithm: Each time AnyEvent::Handle can read C<read_size> bytes in
380one go it will double C<read_size> up to the maximum given by this
381option. Default: C<131072> or C<read_size>, whichever is higher.
346 382
347=item low_water_mark => <bytes> 383=item low_water_mark => <bytes>
348 384
349Sets the amount of bytes (default: C<0>) that make up an "empty" write 385Sets the number of bytes (default: C<0>) that make up an "empty" write
350buffer: If the write reaches this size or gets even samller it is 386buffer: If the buffer reaches this size or gets even samller it is
351considered empty. 387considered empty.
352 388
353Sometimes it can be beneficial (for performance reasons) to add data to 389Sometimes it can be beneficial (for performance reasons) to add data to
354the write buffer before it is fully drained, but this is a rare case, as 390the write buffer before it is fully drained, but this is a rare case, as
355the operating system kernel usually buffers data as well, so the default 391the operating system kernel usually buffers data as well, so the default
356is good in almost all cases. 392is good in almost all cases.
357 393
358=item linger => <seconds> 394=item linger => <seconds>
359 395
360If non-zero (default: C<3600>), then the destructor of the 396If this is non-zero (default: C<3600>), the destructor of the
361AnyEvent::Handle object will check whether there is still outstanding 397AnyEvent::Handle object will check whether there is still outstanding
362write data and will install a watcher that will write this data to the 398write data and will install a watcher that will write this data to the
363socket. No errors will be reported (this mostly matches how the operating 399socket. No errors will be reported (this mostly matches how the operating
364system treats outstanding data at socket close time). 400system treats outstanding data at socket close time).
365 401
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372A string used to identify the remote site - usually the DNS hostname 408A string used to identify the remote site - usually the DNS hostname
373(I<not> IDN!) used to create the connection, rarely the IP address. 409(I<not> IDN!) used to create the connection, rarely the IP address.
374 410
375Apart from being useful in error messages, this string is also used in TLS 411Apart from being useful in error messages, this string is also used in TLS
376peername verification (see C<verify_peername> in L<AnyEvent::TLS>). This 412peername verification (see C<verify_peername> in L<AnyEvent::TLS>). This
377verification will be skipped when C<peername> is not specified or 413verification will be skipped when C<peername> is not specified or is
378C<undef>. 414C<undef>.
379 415
380=item tls => "accept" | "connect" | Net::SSLeay::SSL object 416=item tls => "accept" | "connect" | Net::SSLeay::SSL object
381 417
382When this parameter is given, it enables TLS (SSL) mode, that means 418When this parameter is given, it enables TLS (SSL) mode, that means
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408B<IMPORTANT:> since Net::SSLeay "objects" are really only integers, 444B<IMPORTANT:> since Net::SSLeay "objects" are really only integers,
409passing in the wrong integer will lead to certain crash. This most often 445passing in the wrong integer will lead to certain crash. This most often
410happens when one uses a stylish C<< tls => 1 >> and is surprised about the 446happens when one uses a stylish C<< tls => 1 >> and is surprised about the
411segmentation fault. 447segmentation fault.
412 448
413See the C<< ->starttls >> method for when need to start TLS negotiation later. 449Use the C<< ->starttls >> method if you need to start TLS negotiation later.
414 450
415=item tls_ctx => $anyevent_tls 451=item tls_ctx => $anyevent_tls
416 452
417Use the given C<AnyEvent::TLS> object to create the new TLS connection 453Use the given C<AnyEvent::TLS> object to create the new TLS connection
418(unless a connection object was specified directly). If this parameter is 454(unless a connection object was specified directly). If this
419missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>. 455parameter is missing (or C<undef>), then AnyEvent::Handle will use
456C<AnyEvent::Handle::TLS_CTX>.
420 457
421Instead of an object, you can also specify a hash reference with C<< key 458Instead of an object, you can also specify a hash reference with C<< key
422=> value >> pairs. Those will be passed to L<AnyEvent::TLS> to create a 459=> value >> pairs. Those will be passed to L<AnyEvent::TLS> to create a
423new TLS context object. 460new TLS context object.
424 461
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433 470
434TLS handshake failures will not cause C<on_error> to be invoked when this 471TLS handshake failures will not cause C<on_error> to be invoked when this
435callback is in effect, instead, the error message will be passed to C<on_starttls>. 472callback is in effect, instead, the error message will be passed to C<on_starttls>.
436 473
437Without this callback, handshake failures lead to C<on_error> being 474Without this callback, handshake failures lead to C<on_error> being
438called, as normal. 475called as usual.
439 476
440Note that you cannot call C<starttls> right again in this callback. If you 477Note that you cannot just call C<starttls> again in this callback. If you
441need to do that, start an zero-second timer instead whose callback can 478need to do that, start an zero-second timer instead whose callback can
442then call C<< ->starttls >> again. 479then call C<< ->starttls >> again.
443 480
444=item on_stoptls => $cb->($handle) 481=item on_stoptls => $cb->($handle)
445 482
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493 $self->{connect}[0], 530 $self->{connect}[0],
494 $self->{connect}[1], 531 $self->{connect}[1],
495 sub { 532 sub {
496 my ($fh, $host, $port, $retry) = @_; 533 my ($fh, $host, $port, $retry) = @_;
497 534
535 delete $self->{_connect}; # no longer needed
536
498 if ($fh) { 537 if ($fh) {
499 $self->{fh} = $fh; 538 $self->{fh} = $fh;
500 539
501 delete $self->{_skip_drain_rbuf}; 540 delete $self->{_skip_drain_rbuf};
502 $self->_start; 541 $self->_start;
… …
509 }); 548 });
510 549
511 } else { 550 } else {
512 if ($self->{on_connect_error}) { 551 if ($self->{on_connect_error}) {
513 $self->{on_connect_error}($self, "$!"); 552 $self->{on_connect_error}($self, "$!");
514 $self->destroy; 553 $self->destroy if $self;
515 } else { 554 } else {
516 $self->_error ($!, 1); 555 $self->_error ($!, 1);
517 } 556 }
518 } 557 }
519 }, 558 },
520 sub { 559 sub {
521 local $self->{fh} = $_[0]; 560 local $self->{fh} = $_[0];
522 561
523 $self->{on_prepare} 562 $self->{on_prepare}
524 ? $self->{on_prepare}->($self) 563 ? $self->{on_prepare}->($self)
525 : () 564 : ()
526 } 565 }
527 ); 566 );
528 } 567 }
529 568
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547 586
548 $self->{_activity} = 587 $self->{_activity} =
549 $self->{_ractivity} = 588 $self->{_ractivity} =
550 $self->{_wactivity} = AE::now; 589 $self->{_wactivity} = AE::now;
551 590
591 $self->{read_size} ||= 2048;
592 $self->{max_read_size} = $self->{read_size}
593 if $self->{read_size} > ($self->{max_read_size} || MAX_READ_SIZE);
594
552 $self->timeout (delete $self->{timeout} ) if $self->{timeout}; 595 $self->timeout (delete $self->{timeout} ) if $self->{timeout};
553 $self->rtimeout (delete $self->{rtimeout} ) if $self->{rtimeout}; 596 $self->rtimeout (delete $self->{rtimeout} ) if $self->{rtimeout};
554 $self->wtimeout (delete $self->{wtimeout} ) if $self->{wtimeout}; 597 $self->wtimeout (delete $self->{wtimeout} ) if $self->{wtimeout};
555 598
556 $self->no_delay (delete $self->{no_delay} ) if exists $self->{no_delay} && $self->{no_delay}; 599 $self->no_delay (delete $self->{no_delay} ) if exists $self->{no_delay} && $self->{no_delay};
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559 $self->oobinline (exists $self->{oobinline} ? delete $self->{oobinline} : 1); 602 $self->oobinline (exists $self->{oobinline} ? delete $self->{oobinline} : 1);
560 603
561 $self->starttls (delete $self->{tls}, delete $self->{tls_ctx}) 604 $self->starttls (delete $self->{tls}, delete $self->{tls_ctx})
562 if $self->{tls}; 605 if $self->{tls};
563 606
564 $self->on_drain (delete $self->{on_drain}) if $self->{on_drain}; 607 $self->on_drain (delete $self->{on_drain} ) if $self->{on_drain};
565 608
566 $self->start_read 609 $self->start_read
567 if $self->{on_read} || @{ $self->{_queue} }; 610 if $self->{on_read} || @{ $self->{_queue} };
568 611
569 $self->_drain_wbuf; 612 $self->_drain_wbuf;
… …
645=cut 688=cut
646 689
647sub no_delay { 690sub no_delay {
648 $_[0]{no_delay} = $_[1]; 691 $_[0]{no_delay} = $_[1];
649 692
650 eval {
651 local $SIG{__DIE__};
652 setsockopt $_[0]{fh}, Socket::IPPROTO_TCP (), Socket::TCP_NODELAY (), int $_[1] 693 setsockopt $_[0]{fh}, Socket::IPPROTO_TCP (), Socket::TCP_NODELAY (), int $_[1]
653 if $_[0]{fh}; 694 if $_[0]{fh};
654 };
655} 695}
656 696
657=item $handle->keepalive ($boolean) 697=item $handle->keepalive ($boolean)
658 698
659Enables or disables the C<keepalive> setting (see constructor argument of 699Enables or disables the C<keepalive> setting (see constructor argument of
… …
727 767
728=item $handle->rbuf_max ($max_octets) 768=item $handle->rbuf_max ($max_octets)
729 769
730Configures the C<rbuf_max> setting (C<undef> disables it). 770Configures the C<rbuf_max> setting (C<undef> disables it).
731 771
772=item $handle->wbuf_max ($max_octets)
773
774Configures the C<wbuf_max> setting (C<undef> disables it).
775
732=cut 776=cut
733 777
734sub rbuf_max { 778sub rbuf_max {
735 $_[0]{rbuf_max} = $_[1]; 779 $_[0]{rbuf_max} = $_[1];
736} 780}
737 781
782sub wbuf_max {
783 $_[0]{wbuf_max} = $_[1];
784}
785
738############################################################################# 786#############################################################################
739 787
740=item $handle->timeout ($seconds) 788=item $handle->timeout ($seconds)
741 789
742=item $handle->rtimeout ($seconds) 790=item $handle->rtimeout ($seconds)
743 791
744=item $handle->wtimeout ($seconds) 792=item $handle->wtimeout ($seconds)
745 793
746Configures (or disables) the inactivity timeout. 794Configures (or disables) the inactivity timeout.
795
796The timeout will be checked instantly, so this method might destroy the
797handle before it returns.
747 798
748=item $handle->timeout_reset 799=item $handle->timeout_reset
749 800
750=item $handle->rtimeout_reset 801=item $handle->rtimeout_reset
751 802
… …
768 $_[0]{$on_timeout} = $_[1]; 819 $_[0]{$on_timeout} = $_[1];
769 }; 820 };
770 821
771 *$timeout = sub { 822 *$timeout = sub {
772 my ($self, $new_value) = @_; 823 my ($self, $new_value) = @_;
824
825 $new_value >= 0
826 or Carp::croak "AnyEvent::Handle->$timeout called with negative timeout ($new_value), caught";
773 827
774 $self->{$timeout} = $new_value; 828 $self->{$timeout} = $new_value;
775 delete $self->{$tw}; &$cb; 829 delete $self->{$tw}; &$cb;
776 }; 830 };
777 831
… …
832 886
833The write queue is very simple: you can add data to its end, and 887The write queue is very simple: you can add data to its end, and
834AnyEvent::Handle will automatically try to get rid of it for you. 888AnyEvent::Handle will automatically try to get rid of it for you.
835 889
836When data could be written and the write buffer is shorter then the low 890When data could be written and the write buffer is shorter then the low
837water mark, the C<on_drain> callback will be invoked. 891water mark, the C<on_drain> callback will be invoked once.
838 892
839=over 4 893=over 4
840 894
841=item $handle->on_drain ($cb) 895=item $handle->on_drain ($cb)
842 896
… …
857 if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf}); 911 if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf});
858} 912}
859 913
860=item $handle->push_write ($data) 914=item $handle->push_write ($data)
861 915
862Queues the given scalar to be written. You can push as much data as you 916Queues the given scalar to be written. You can push as much data as
863want (only limited by the available memory), as C<AnyEvent::Handle> 917you want (only limited by the available memory and C<wbuf_max>), as
864buffers it independently of the kernel. 918C<AnyEvent::Handle> buffers it independently of the kernel.
865 919
866This method may invoke callbacks (and therefore the handle might be 920This method may invoke callbacks (and therefore the handle might be
867destroyed after it returns). 921destroyed after it returns).
868 922
869=cut 923=cut
… …
897 $cb->() unless $self->{autocork}; 951 $cb->() unless $self->{autocork};
898 952
899 # if still data left in wbuf, we need to poll 953 # if still data left in wbuf, we need to poll
900 $self->{_ww} = AE::io $self->{fh}, 1, $cb 954 $self->{_ww} = AE::io $self->{fh}, 1, $cb
901 if length $self->{wbuf}; 955 if length $self->{wbuf};
956
957 if (
958 defined $self->{wbuf_max}
959 && $self->{wbuf_max} < length $self->{wbuf}
960 ) {
961 $self->_error (Errno::ENOSPC, 1), return;
962 }
902 }; 963 };
903} 964}
904 965
905our %WH; 966our %WH;
906 967
… …
1026=cut 1087=cut
1027 1088
1028register_write_type storable => sub { 1089register_write_type storable => sub {
1029 my ($self, $ref) = @_; 1090 my ($self, $ref) = @_;
1030 1091
1031 require Storable; 1092 require Storable unless $Storable::VERSION;
1032 1093
1033 pack "w/a*", Storable::nfreeze ($ref) 1094 pack "w/a*", Storable::nfreeze ($ref)
1034}; 1095};
1035 1096
1036=back 1097=back
… …
1041before it was actually written. One way to do that is to replace your 1102before it was actually written. One way to do that is to replace your
1042C<on_drain> handler by a callback that shuts down the socket (and set 1103C<on_drain> handler by a callback that shuts down the socket (and set
1043C<low_water_mark> to C<0>). This method is a shorthand for just that, and 1104C<low_water_mark> to C<0>). This method is a shorthand for just that, and
1044replaces the C<on_drain> callback with: 1105replaces the C<on_drain> callback with:
1045 1106
1046 sub { shutdown $_[0]{fh}, 1 } # for push_shutdown 1107 sub { shutdown $_[0]{fh}, 1 }
1047 1108
1048This simply shuts down the write side and signals an EOF condition to the 1109This simply shuts down the write side and signals an EOF condition to the
1049the peer. 1110the peer.
1050 1111
1051You can rely on the normal read queue and C<on_eof> handling 1112You can rely on the normal read queue and C<on_eof> handling
… …
1073 1134
1074Whenever the given C<type> is used, C<push_write> will the function with 1135Whenever the given C<type> is used, C<push_write> will the function with
1075the handle object and the remaining arguments. 1136the handle object and the remaining arguments.
1076 1137
1077The function is supposed to return a single octet string that will be 1138The function is supposed to return a single octet string that will be
1078appended to the write buffer, so you cna mentally treat this function as a 1139appended to the write buffer, so you can mentally treat this function as a
1079"arguments to on-the-wire-format" converter. 1140"arguments to on-the-wire-format" converter.
1080 1141
1081Example: implement a custom write type C<join> that joins the remaining 1142Example: implement a custom write type C<join> that joins the remaining
1082arguments using the first one. 1143arguments using the first one.
1083 1144
… …
1117partial message has been received so far), or change the read queue with 1178partial message has been received so far), or change the read queue with
1118e.g. C<push_read>. 1179e.g. C<push_read>.
1119 1180
1120In the more complex case, you want to queue multiple callbacks. In this 1181In the more complex case, you want to queue multiple callbacks. In this
1121case, AnyEvent::Handle will call the first queued callback each time new 1182case, AnyEvent::Handle will call the first queued callback each time new
1122data arrives (also the first time it is queued) and removes it when it has 1183data arrives (also the first time it is queued) and remove it when it has
1123done its job (see C<push_read>, below). 1184done its job (see C<push_read>, below).
1124 1185
1125This way you can, for example, push three line-reads, followed by reading 1186This way you can, for example, push three line-reads, followed by reading
1126a chunk of data, and AnyEvent::Handle will execute them in order. 1187a chunk of data, and AnyEvent::Handle will execute them in order.
1127 1188
… …
1272 $self->_drain_rbuf if $cb; 1333 $self->_drain_rbuf if $cb;
1273} 1334}
1274 1335
1275=item $handle->rbuf 1336=item $handle->rbuf
1276 1337
1277Returns the read buffer (as a modifiable lvalue). 1338Returns the read buffer (as a modifiable lvalue). You can also access the
1339read buffer directly as the C<< ->{rbuf} >> member, if you want (this is
1340much faster, and no less clean).
1278 1341
1279You can access the read buffer directly as the C<< ->{rbuf} >> 1342The only operation allowed on the read buffer (apart from looking at it)
1280member, if you want. However, the only operation allowed on the 1343is removing data from its beginning. Otherwise modifying or appending to
1281read buffer (apart from looking at it) is removing data from its 1344it is not allowed and will lead to hard-to-track-down bugs.
1282beginning. Otherwise modifying or appending to it is not allowed and will
1283lead to hard-to-track-down bugs.
1284 1345
1285NOTE: The read buffer should only be used or modified if the C<on_read>, 1346NOTE: The read buffer should only be used or modified in the C<on_read>
1286C<push_read> or C<unshift_read> methods are used. The other read methods 1347callback or when C<push_read> or C<unshift_read> are used with a single
1287automatically manage the read buffer. 1348callback (i.e. untyped). Typed C<push_read> and C<unshift_read> methods
1349will manage the read buffer on their own.
1288 1350
1289=cut 1351=cut
1290 1352
1291sub rbuf : lvalue { 1353sub rbuf : lvalue {
1292 $_[0]{rbuf} 1354 $_[0]{rbuf}
… …
1343 my $cb = pop; 1405 my $cb = pop;
1344 1406
1345 if (@_) { 1407 if (@_) {
1346 my $type = shift; 1408 my $type = shift;
1347 1409
1410 $cb = ($RH{$type} ||= _load_func "$type\::anyevent_read_type"
1348 $cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::unshift_read") 1411 or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::unshift_read")
1349 ->($self, $cb, @_); 1412 ->($self, $cb, @_);
1350 } 1413 }
1351 1414
1352 unshift @{ $self->{_queue} }, $cb; 1415 unshift @{ $self->{_queue} }, $cb;
1353 $self->_drain_rbuf; 1416 $self->_drain_rbuf;
… …
1375data. 1438data.
1376 1439
1377Example: read 2 bytes. 1440Example: read 2 bytes.
1378 1441
1379 $handle->push_read (chunk => 2, sub { 1442 $handle->push_read (chunk => 2, sub {
1380 warn "yay ", unpack "H*", $_[1]; 1443 say "yay " . unpack "H*", $_[1];
1381 }); 1444 });
1382 1445
1383=cut 1446=cut
1384 1447
1385register_read_type chunk => sub { 1448register_read_type chunk => sub {
… …
1419 if (@_ < 3) { 1482 if (@_ < 3) {
1420 # this is more than twice as fast as the generic code below 1483 # this is more than twice as fast as the generic code below
1421 sub { 1484 sub {
1422 $_[0]{rbuf} =~ s/^([^\015\012]*)(\015?\012)// or return; 1485 $_[0]{rbuf} =~ s/^([^\015\012]*)(\015?\012)// or return;
1423 1486
1424 $cb->($_[0], $1, $2); 1487 $cb->($_[0], "$1", "$2");
1425 1 1488 1
1426 } 1489 }
1427 } else { 1490 } else {
1428 $eol = quotemeta $eol unless ref $eol; 1491 $eol = quotemeta $eol unless ref $eol;
1429 $eol = qr|^(.*?)($eol)|s; 1492 $eol = qr|^(.*?)($eol)|s;
1430 1493
1431 sub { 1494 sub {
1432 $_[0]{rbuf} =~ s/$eol// or return; 1495 $_[0]{rbuf} =~ s/$eol// or return;
1433 1496
1434 $cb->($_[0], $1, $2); 1497 $cb->($_[0], "$1", "$2");
1435 1 1498 1
1436 } 1499 }
1437 } 1500 }
1438}; 1501};
1439 1502
… …
1461the receive buffer when neither C<$accept> nor C<$reject> match, 1524the receive buffer when neither C<$accept> nor C<$reject> match,
1462and everything preceding and including the match will be accepted 1525and everything preceding and including the match will be accepted
1463unconditionally. This is useful to skip large amounts of data that you 1526unconditionally. This is useful to skip large amounts of data that you
1464know cannot be matched, so that the C<$accept> or C<$reject> regex do not 1527know cannot be matched, so that the C<$accept> or C<$reject> regex do not
1465have to start matching from the beginning. This is purely an optimisation 1528have to start matching from the beginning. This is purely an optimisation
1466and is usually worth only when you expect more than a few kilobytes. 1529and is usually worth it only when you expect more than a few kilobytes.
1467 1530
1468Example: expect a http header, which ends at C<\015\012\015\012>. Since we 1531Example: expect a http header, which ends at C<\015\012\015\012>. Since we
1469expect the header to be very large (it isn't in practise, but...), we use 1532expect the header to be very large (it isn't in practice, but...), we use
1470a skip regex to skip initial portions. The skip regex is tricky in that 1533a skip regex to skip initial portions. The skip regex is tricky in that
1471it only accepts something not ending in either \015 or \012, as these are 1534it only accepts something not ending in either \015 or \012, as these are
1472required for the accept regex. 1535required for the accept regex.
1473 1536
1474 $handle->push_read (regex => 1537 $handle->push_read (regex =>
… …
1487 1550
1488 sub { 1551 sub {
1489 # accept 1552 # accept
1490 if ($$rbuf =~ $accept) { 1553 if ($$rbuf =~ $accept) {
1491 $data .= substr $$rbuf, 0, $+[0], ""; 1554 $data .= substr $$rbuf, 0, $+[0], "";
1492 $cb->($self, $data); 1555 $cb->($_[0], $data);
1493 return 1; 1556 return 1;
1494 } 1557 }
1495 1558
1496 # reject 1559 # reject
1497 if ($reject && $$rbuf =~ $reject) { 1560 if ($reject && $$rbuf =~ $reject) {
1498 $self->_error (Errno::EBADMSG); 1561 $_[0]->_error (Errno::EBADMSG);
1499 } 1562 }
1500 1563
1501 # skip 1564 # skip
1502 if ($skip && $$rbuf =~ $skip) { 1565 if ($skip && $$rbuf =~ $skip) {
1503 $data .= substr $$rbuf, 0, $+[0], ""; 1566 $data .= substr $$rbuf, 0, $+[0], "";
… …
1519 my ($self, $cb) = @_; 1582 my ($self, $cb) = @_;
1520 1583
1521 sub { 1584 sub {
1522 unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) { 1585 unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
1523 if ($_[0]{rbuf} =~ /[^0-9]/) { 1586 if ($_[0]{rbuf} =~ /[^0-9]/) {
1524 $self->_error (Errno::EBADMSG); 1587 $_[0]->_error (Errno::EBADMSG);
1525 } 1588 }
1526 return; 1589 return;
1527 } 1590 }
1528 1591
1529 my $len = $1; 1592 my $len = $1;
1530 1593
1531 $self->unshift_read (chunk => $len, sub { 1594 $_[0]->unshift_read (chunk => $len, sub {
1532 my $string = $_[1]; 1595 my $string = $_[1];
1533 $_[0]->unshift_read (chunk => 1, sub { 1596 $_[0]->unshift_read (chunk => 1, sub {
1534 if ($_[1] eq ",") { 1597 if ($_[1] eq ",") {
1535 $cb->($_[0], $string); 1598 $cb->($_[0], $string);
1536 } else { 1599 } else {
1537 $self->_error (Errno::EBADMSG); 1600 $_[0]->_error (Errno::EBADMSG);
1538 } 1601 }
1539 }); 1602 });
1540 }); 1603 });
1541 1604
1542 1 1605 1
… …
1615 1678
1616 my $data; 1679 my $data;
1617 my $rbuf = \$self->{rbuf}; 1680 my $rbuf = \$self->{rbuf};
1618 1681
1619 sub { 1682 sub {
1620 my $ref = eval { $json->incr_parse ($self->{rbuf}) }; 1683 my $ref = eval { $json->incr_parse ($_[0]{rbuf}) };
1621 1684
1622 if ($ref) { 1685 if ($ref) {
1623 $self->{rbuf} = $json->incr_text; 1686 $_[0]{rbuf} = $json->incr_text;
1624 $json->incr_text = ""; 1687 $json->incr_text = "";
1625 $cb->($self, $ref); 1688 $cb->($_[0], $ref);
1626 1689
1627 1 1690 1
1628 } elsif ($@) { 1691 } elsif ($@) {
1629 # error case 1692 # error case
1630 $json->incr_skip; 1693 $json->incr_skip;
1631 1694
1632 $self->{rbuf} = $json->incr_text; 1695 $_[0]{rbuf} = $json->incr_text;
1633 $json->incr_text = ""; 1696 $json->incr_text = "";
1634 1697
1635 $self->_error (Errno::EBADMSG); 1698 $_[0]->_error (Errno::EBADMSG);
1636 1699
1637 () 1700 ()
1638 } else { 1701 } else {
1639 $self->{rbuf} = ""; 1702 $_[0]{rbuf} = "";
1640 1703
1641 () 1704 ()
1642 } 1705 }
1643 } 1706 }
1644}; 1707};
… …
1654=cut 1717=cut
1655 1718
1656register_read_type storable => sub { 1719register_read_type storable => sub {
1657 my ($self, $cb) = @_; 1720 my ($self, $cb) = @_;
1658 1721
1659 require Storable; 1722 require Storable unless $Storable::VERSION;
1660 1723
1661 sub { 1724 sub {
1662 # when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method 1725 # when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
1663 defined (my $len = eval { unpack "w", $_[0]{rbuf} }) 1726 defined (my $len = eval { unpack "w", $_[0]{rbuf} })
1664 or return; 1727 or return;
… …
1677 # read remaining chunk 1740 # read remaining chunk
1678 $_[0]->unshift_read (chunk => $len, sub { 1741 $_[0]->unshift_read (chunk => $len, sub {
1679 if (my $ref = eval { Storable::thaw ($_[1]) }) { 1742 if (my $ref = eval { Storable::thaw ($_[1]) }) {
1680 $cb->($_[0], $ref); 1743 $cb->($_[0], $ref);
1681 } else { 1744 } else {
1682 $self->_error (Errno::EBADMSG); 1745 $_[0]->_error (Errno::EBADMSG);
1683 } 1746 }
1684 }); 1747 });
1685 } 1748 }
1686 1749
1687 1 1750 1
… …
1725Note that AnyEvent::Handle will automatically C<start_read> for you when 1788Note that AnyEvent::Handle will automatically C<start_read> for you when
1726you change the C<on_read> callback or push/unshift a read callback, and it 1789you change the C<on_read> callback or push/unshift a read callback, and it
1727will automatically C<stop_read> for you when neither C<on_read> is set nor 1790will automatically C<stop_read> for you when neither C<on_read> is set nor
1728there are any read requests in the queue. 1791there are any read requests in the queue.
1729 1792
1730These methods will have no effect when in TLS mode (as TLS doesn't support 1793In older versions of this module (<= 5.3), these methods had no effect,
1731half-duplex connections). 1794as TLS does not support half-duplex connections. In current versions they
1795work as expected, as this behaviour is required to avoid certain resource
1796attacks, where the program would be forced to read (and buffer) arbitrary
1797amounts of data before being able to send some data. The drawback is that
1798some readings of the the SSL/TLS specifications basically require this
1799attack to be working, as SSL/TLS implementations might stall sending data
1800during a rehandshake.
1801
1802As a guideline, during the initial handshake, you should not stop reading,
1803and as a client, it might cause problems, depending on your application.
1732 1804
1733=cut 1805=cut
1734 1806
1735sub stop_read { 1807sub stop_read {
1736 my ($self) = @_; 1808 my ($self) = @_;
1737 1809
1738 delete $self->{_rw} unless $self->{tls}; 1810 delete $self->{_rw};
1739} 1811}
1740 1812
1741sub start_read { 1813sub start_read {
1742 my ($self) = @_; 1814 my ($self) = @_;
1743 1815
1744 unless ($self->{_rw} || $self->{_eof} || !$self->{fh}) { 1816 unless ($self->{_rw} || $self->{_eof} || !$self->{fh}) {
1745 Scalar::Util::weaken $self; 1817 Scalar::Util::weaken $self;
1746 1818
1747 $self->{_rw} = AE::io $self->{fh}, 0, sub { 1819 $self->{_rw} = AE::io $self->{fh}, 0, sub {
1748 my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf}); 1820 my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf});
1749 my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf; 1821 my $len = sysread $self->{fh}, $$rbuf, $self->{read_size}, length $$rbuf;
1750 1822
1751 if ($len > 0) { 1823 if ($len > 0) {
1752 $self->{_activity} = $self->{_ractivity} = AE::now; 1824 $self->{_activity} = $self->{_ractivity} = AE::now;
1753 1825
1754 if ($self->{tls}) { 1826 if ($self->{tls}) {
1755 Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf); 1827 Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf);
1756 1828
1757 &_dotls ($self); 1829 &_dotls ($self);
1758 } else { 1830 } else {
1759 $self->_drain_rbuf; 1831 $self->_drain_rbuf;
1832 }
1833
1834 if ($len == $self->{read_size}) {
1835 $self->{read_size} *= 2;
1836 $self->{read_size} = $self->{max_read_size} || MAX_READ_SIZE
1837 if $self->{read_size} > ($self->{max_read_size} || MAX_READ_SIZE);
1760 } 1838 }
1761 1839
1762 } elsif (defined $len) { 1840 } elsif (defined $len) {
1763 delete $self->{_rw}; 1841 delete $self->{_rw};
1764 $self->{_eof} = 1; 1842 $self->{_eof} = 1;
… …
1874context in C<< $handle->{tls_ctx} >> after this call and can be used or 1952context in C<< $handle->{tls_ctx} >> after this call and can be used or
1875changed to your liking. Note that the handshake might have already started 1953changed to your liking. Note that the handshake might have already started
1876when this function returns. 1954when this function returns.
1877 1955
1878Due to bugs in OpenSSL, it might or might not be possible to do multiple 1956Due to bugs in OpenSSL, it might or might not be possible to do multiple
1879handshakes on the same stream. Best do not attempt to use the stream after 1957handshakes on the same stream. It is best to not attempt to use the
1880stopping TLS. 1958stream after stopping TLS.
1881 1959
1882This method may invoke callbacks (and therefore the handle might be 1960This method may invoke callbacks (and therefore the handle might be
1883destroyed after it returns). 1961destroyed after it returns).
1884 1962
1885=cut 1963=cut
… …
1939 Net::SSLeay::CTX_set_mode ($tls, 1|2); 2017 Net::SSLeay::CTX_set_mode ($tls, 1|2);
1940 2018
1941 $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); 2019 $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1942 $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); 2020 $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1943 2021
1944 Net::SSLeay::BIO_write ($self->{_rbio}, delete $self->{rbuf}); 2022 Net::SSLeay::BIO_write ($self->{_rbio}, $self->{rbuf});
2023 $self->{rbuf} = "";
1945 2024
1946 Net::SSLeay::set_bio ($tls, $self->{_rbio}, $self->{_wbio}); 2025 Net::SSLeay::set_bio ($tls, $self->{_rbio}, $self->{_wbio});
1947 2026
1948 $self->{_on_starttls} = sub { $_[0]{on_starttls}(@_) } 2027 $self->{_on_starttls} = sub { $_[0]{on_starttls}(@_) }
1949 if $self->{on_starttls}; 2028 if $self->{on_starttls};
… …
1987 if $self->{tls} > 0; 2066 if $self->{tls} > 0;
1988 2067
1989 delete @$self{qw(_rbio _wbio _tls_wbuf _on_starttls)}; 2068 delete @$self{qw(_rbio _wbio _tls_wbuf _on_starttls)};
1990} 2069}
1991 2070
2071=item $handle->resettls
2072
2073This rarely-used method simply resets and TLS state on the handle, usually
2074causing data loss.
2075
2076One case where it may be useful is when you want to skip over the data in
2077the stream but you are not interested in interpreting it, so data loss is
2078no concern.
2079
2080=cut
2081
2082*resettls = \&_freetls;
2083
1992sub DESTROY { 2084sub DESTROY {
1993 my ($self) = @_; 2085 my ($self) = @_;
1994 2086
1995 &_freetls; 2087 &_freetls;
1996 2088
… …
2005 push @linger, AE::io $fh, 1, sub { 2097 push @linger, AE::io $fh, 1, sub {
2006 my $len = syswrite $fh, $wbuf, length $wbuf; 2098 my $len = syswrite $fh, $wbuf, length $wbuf;
2007 2099
2008 if ($len > 0) { 2100 if ($len > 0) {
2009 substr $wbuf, 0, $len, ""; 2101 substr $wbuf, 0, $len, "";
2010 } else { 2102 } elsif (defined $len || ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK)) {
2011 @linger = (); # end 2103 @linger = (); # end
2012 } 2104 }
2013 }; 2105 };
2014 push @linger, AE::timer $linger, 0, sub { 2106 push @linger, AE::timer $linger, 0, sub {
2015 @linger = (); 2107 @linger = ();
… …
2111 2203
2112It is only safe to "forget" the reference inside EOF or error callbacks, 2204It is only safe to "forget" the reference inside EOF or error callbacks,
2113from within all other callbacks, you need to explicitly call the C<< 2205from within all other callbacks, you need to explicitly call the C<<
2114->destroy >> method. 2206->destroy >> method.
2115 2207
2208=item Why is my C<on_eof> callback never called?
2209
2210Probably because your C<on_error> callback is being called instead: When
2211you have outstanding requests in your read queue, then an EOF is
2212considered an error as you clearly expected some data.
2213
2214To avoid this, make sure you have an empty read queue whenever your handle
2215is supposed to be "idle" (i.e. connection closes are O.K.). You can set
2216an C<on_read> handler that simply pushes the first read requests in the
2217queue.
2218
2219See also the next question, which explains this in a bit more detail.
2220
2221=item How can I serve requests in a loop?
2222
2223Most protocols consist of some setup phase (authentication for example)
2224followed by a request handling phase, where the server waits for requests
2225and handles them, in a loop.
2226
2227There are two important variants: The first (traditional, better) variant
2228handles requests until the server gets some QUIT command, causing it to
2229close the connection first (highly desirable for a busy TCP server). A
2230client dropping the connection is an error, which means this variant can
2231detect an unexpected detection close.
2232
2233To handle this case, always make sure you have a on-empty read queue, by
2234pushing the "read request start" handler on it:
2235
2236 # we assume a request starts with a single line
2237 my @start_request; @start_request = (line => sub {
2238 my ($hdl, $line) = @_;
2239
2240 ... handle request
2241
2242 # push next request read, possibly from a nested callback
2243 $hdl->push_read (@start_request);
2244 });
2245
2246 # auth done, now go into request handling loop
2247 # now push the first @start_request
2248 $hdl->push_read (@start_request);
2249
2250By always having an outstanding C<push_read>, the handle always expects
2251some data and raises the C<EPIPE> error when the connction is dropped
2252unexpectedly.
2253
2254The second variant is a protocol where the client can drop the connection
2255at any time. For TCP, this means that the server machine may run out of
2256sockets easier, and in general, it means you cannot distinguish a protocl
2257failure/client crash from a normal connection close. Nevertheless, these
2258kinds of protocols are common (and sometimes even the best solution to the
2259problem).
2260
2261Having an outstanding read request at all times is possible if you ignore
2262C<EPIPE> errors, but this doesn't help with when the client drops the
2263connection during a request, which would still be an error.
2264
2265A better solution is to push the initial request read in an C<on_read>
2266callback. This avoids an error, as when the server doesn't expect data
2267(i.e. is idly waiting for the next request, an EOF will not raise an
2268error, but simply result in an C<on_eof> callback. It is also a bit slower
2269and simpler:
2270
2271 # auth done, now go into request handling loop
2272 $hdl->on_read (sub {
2273 my ($hdl) = @_;
2274
2275 # called each time we receive data but the read queue is empty
2276 # simply start read the request
2277
2278 $hdl->push_read (line => sub {
2279 my ($hdl, $line) = @_;
2280
2281 ... handle request
2282
2283 # do nothing special when the request has been handled, just
2284 # let the request queue go empty.
2285 });
2286 });
2287
2116=item I get different callback invocations in TLS mode/Why can't I pause 2288=item I get different callback invocations in TLS mode/Why can't I pause
2117reading? 2289reading?
2118 2290
2119Unlike, say, TCP, TLS connections do not consist of two independent 2291Unlike, say, TCP, TLS connections do not consist of two independent
2120communication channels, one for each direction. Or put differently. The 2292communication channels, one for each direction. Or put differently, the
2121read and write directions are not independent of each other: you cannot 2293read and write directions are not independent of each other: you cannot
2122write data unless you are also prepared to read, and vice versa. 2294write data unless you are also prepared to read, and vice versa.
2123 2295
2124This can mean than, in TLS mode, you might get C<on_error> or C<on_eof> 2296This means that, in TLS mode, you might get C<on_error> or C<on_eof>
2125callback invocations when you are not expecting any read data - the reason 2297callback invocations when you are not expecting any read data - the reason
2126is that AnyEvent::Handle always reads in TLS mode. 2298is that AnyEvent::Handle always reads in TLS mode.
2127 2299
2128During the connection, you have to make sure that you always have a 2300During the connection, you have to make sure that you always have a
2129non-empty read-queue, or an C<on_read> watcher. At the end of the 2301non-empty read-queue, or an C<on_read> watcher. At the end of the
… …
2141 $handle->on_eof (undef); 2313 $handle->on_eof (undef);
2142 $handle->on_error (sub { 2314 $handle->on_error (sub {
2143 my $data = delete $_[0]{rbuf}; 2315 my $data = delete $_[0]{rbuf};
2144 }); 2316 });
2145 2317
2318Note that this example removes the C<rbuf> member from the handle object,
2319which is not normally allowed by the API. It is expressly permitted in
2320this case only, as the handle object needs to be destroyed afterwards.
2321
2146The reason to use C<on_error> is that TCP connections, due to latencies 2322The reason to use C<on_error> is that TCP connections, due to latencies
2147and packets loss, might get closed quite violently with an error, when in 2323and packets loss, might get closed quite violently with an error, when in
2148fact, all data has been received. 2324fact all data has been received.
2149 2325
2150It is usually better to use acknowledgements when transferring data, 2326It is usually better to use acknowledgements when transferring data,
2151to make sure the other side hasn't just died and you got the data 2327to make sure the other side hasn't just died and you got the data
2152intact. This is also one reason why so many internet protocols have an 2328intact. This is also one reason why so many internet protocols have an
2153explicit QUIT command. 2329explicit QUIT command.
… …
2160C<low_water_mark> this will be called precisely when all data has been 2336C<low_water_mark> this will be called precisely when all data has been
2161written to the socket: 2337written to the socket:
2162 2338
2163 $handle->push_write (...); 2339 $handle->push_write (...);
2164 $handle->on_drain (sub { 2340 $handle->on_drain (sub {
2165 warn "all data submitted to the kernel\n"; 2341 AE::log debug => "all data submitted to the kernel\n";
2166 undef $handle; 2342 undef $handle;
2167 }); 2343 });
2168 2344
2169If you just want to queue some data and then signal EOF to the other side, 2345If you just want to queue some data and then signal EOF to the other side,
2170consider using C<< ->push_shutdown >> instead. 2346consider using C<< ->push_shutdown >> instead.
2171 2347
2172=item I want to contact a TLS/SSL server, I don't care about security. 2348=item I want to contact a TLS/SSL server, I don't care about security.
2173 2349
2174If your TLS server is a pure TLS server (e.g. HTTPS) that only speaks TLS, 2350If your TLS server is a pure TLS server (e.g. HTTPS) that only speaks TLS,
2175simply connect to it and then create the AnyEvent::Handle with the C<tls> 2351connect to it and then create the AnyEvent::Handle with the C<tls>
2176parameter: 2352parameter:
2177 2353
2178 tcp_connect $host, $port, sub { 2354 tcp_connect $host, $port, sub {
2179 my ($fh) = @_; 2355 my ($fh) = @_;
2180 2356
… …
2280 2456
2281=item * all members not documented here and not prefixed with an underscore 2457=item * all members not documented here and not prefixed with an underscore
2282are free to use in subclasses. 2458are free to use in subclasses.
2283 2459
2284Of course, new versions of AnyEvent::Handle may introduce more "public" 2460Of course, new versions of AnyEvent::Handle may introduce more "public"
2285member variables, but thats just life, at least it is documented. 2461member variables, but that's just life. At least it is documented.
2286 2462
2287=back 2463=back
2288 2464
2289=head1 AUTHOR 2465=head1 AUTHOR
2290 2466

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