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Revision 1.185 by root, Thu Sep 3 19:48:27 2009 UTC vs.
Revision 1.235 by root, Tue May 8 19:41:22 2012 UTC

1=head1 NAME 1=head1 NAME
2 2
3AnyEvent::Handle - non-blocking I/O on file handles via AnyEvent 3AnyEvent::Handle - non-blocking I/O on streaming handles via AnyEvent
4 4
5=head1 SYNOPSIS 5=head1 SYNOPSIS
6 6
7 use AnyEvent; 7 use AnyEvent;
8 use AnyEvent::Handle; 8 use AnyEvent::Handle;
… …
11 11
12 my $hdl; $hdl = new AnyEvent::Handle 12 my $hdl; $hdl = new AnyEvent::Handle
13 fh => \*STDIN, 13 fh => \*STDIN,
14 on_error => sub { 14 on_error => sub {
15 my ($hdl, $fatal, $msg) = @_; 15 my ($hdl, $fatal, $msg) = @_;
16 warn "got error $msg\n"; 16 AE::log error => $msg;
17 $hdl->destroy; 17 $hdl->destroy;
18 $cv->send; 18 $cv->send;
19 ); 19 };
20 20
21 # send some request line 21 # send some request line
22 $hdl->push_write ("getinfo\015\012"); 22 $hdl->push_write ("getinfo\015\012");
23 23
24 # read the response line 24 # read the response line
25 $hdl->push_read (line => sub { 25 $hdl->push_read (line => sub {
26 my ($hdl, $line) = @_; 26 my ($hdl, $line) = @_;
27 warn "got line <$line>\n"; 27 say "got line <$line>";
28 $cv->send; 28 $cv->send;
29 }); 29 });
30 30
31 $cv->recv; 31 $cv->recv;
32 32
33=head1 DESCRIPTION 33=head1 DESCRIPTION
34 34
35This module is a helper module to make it easier to do event-based I/O on 35This is a helper module to make it easier to do event-based I/O on
36filehandles. 36stream-based filehandles (sockets, pipes, and other stream things).
37 37
38The L<AnyEvent::Intro> tutorial contains some well-documented 38The L<AnyEvent::Intro> tutorial contains some well-documented
39AnyEvent::Handle examples. 39AnyEvent::Handle examples.
40 40
41In the following, when the documentation refers to of "bytes" then this 41In the following, where the documentation refers to "bytes", it means
42means characters. As sysread and syswrite are used for all I/O, their 42characters. As sysread and syswrite are used for all I/O, their
43treatment of characters applies to this module as well. 43treatment of characters applies to this module as well.
44 44
45At the very minimum, you should specify C<fh> or C<connect>, and the 45At the very minimum, you should specify C<fh> or C<connect>, and the
46C<on_error> callback. 46C<on_error> callback.
47 47
… …
75 } 75 }
76 76
77 \&$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::TLS fh => $filehandle, key => value... 86=item $handle = B<new> AnyEvent::Handle fh => $filehandle, key => value...
85 87
86The constructor supports these arguments (all as C<< key => value >> pairs). 88The constructor supports these arguments (all as C<< key => value >> pairs).
87 89
88=over 4 90=over 4
89 91
… …
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<$retry> will continue with the next conenction target (in case of 141continue with the next connection target (in case of multi-homed hosts or
135multi-homed hosts or SRV records there can be multiple connection 142SRV records there can be multiple connection endpoints). The C<$retry>
136endpoints). When it is called then the read and write queues, eof status, 143callback can be invoked after the connect callback returns, i.e. one can
137tls status and similar properties of the handle are being reset. 144start a handshake and then decide to retry with the next host if the
145handshake fails.
138 146
139In most cases, ignoring the C<$retry> parameter is the way to go. 147In most cases, you should ignore the C<$retry> parameter.
140 148
141=item on_connect_error => $cb->($handle, $message) 149=item on_connect_error => $cb->($handle, $message)
142 150
143This callback is called when the conenction could not be 151This callback is called when the connection could not be
144established. C<$!> will contain the relevant error code, and C<$message> a 152established. C<$!> will contain the relevant error code, and C<$message> a
145message describing it (usually the same as C<"$!">). 153message describing it (usually the same as C<"$!">).
146 154
147If this callback isn't specified, then C<on_error> will be called with a 155If this callback isn't specified, then C<on_error> will be called with a
148fatal error instead. 156fatal error instead.
… …
151 159
152=item on_error => $cb->($handle, $fatal, $message) 160=item on_error => $cb->($handle, $fatal, $message)
153 161
154This is the error callback, which is called when, well, some error 162This is the error callback, which is called when, well, some error
155occured, such as not being able to resolve the hostname, failure to 163occured, such as not being able to resolve the hostname, failure to
156connect or a read error. 164connect, or a read error.
157 165
158Some errors are fatal (which is indicated by C<$fatal> being true). On 166Some errors are fatal (which is indicated by C<$fatal> being true). On
159fatal errors the handle object will be destroyed (by a call to C<< -> 167fatal errors the handle object will be destroyed (by a call to C<< ->
160destroy >>) after invoking the error callback (which means you are free to 168destroy >>) after invoking the error callback (which means you are free to
161examine the handle object). Examples of fatal errors are an EOF condition 169examine the handle object). Examples of fatal errors are an EOF condition
162with active (but unsatisifable) read watchers (C<EPIPE>) or I/O errors. In 170with active (but unsatisfiable) read watchers (C<EPIPE>) or I/O errors. In
163cases where the other side can close the connection at their will it is 171cases where the other side can close the connection at will, it is
164often easiest to not report C<EPIPE> errors in this callback. 172often easiest to not report C<EPIPE> errors in this callback.
165 173
166AnyEvent::Handle tries to find an appropriate error code for you to check 174AnyEvent::Handle tries to find an appropriate error code for you to check
167against, but in some cases (TLS errors), this does not work well. It is 175against, but in some cases (TLS errors), this does not work well.
168recommended to always output the C<$message> argument in human-readable
169error messages (it's usually the same as C<"$!">).
170 176
177If you report the error to the user, it is recommended to always output
178the C<$message> argument in human-readable error messages (you don't need
179to report C<"$!"> if you report C<$message>).
180
181If you want to react programmatically to the error, then looking at C<$!>
182and comparing it against some of the documented C<Errno> values is usually
183better than looking at the C<$message>.
184
171Non-fatal errors can be retried by simply returning, but it is recommended 185Non-fatal errors can be retried by returning, but it is recommended
172to simply ignore this parameter and instead abondon the handle object 186to simply ignore this parameter and instead abondon the handle object
173when this callback is invoked. Examples of non-fatal errors are timeouts 187when this callback is invoked. Examples of non-fatal errors are timeouts
174C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>). 188C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>).
175 189
176On callback entrance, the value of C<$!> contains the operating system 190On entry to the callback, the value of C<$!> contains the operating
177error code (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT>, C<EBADMSG> or 191system error code (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT>, C<EBADMSG> or
178C<EPROTO>). 192C<EPROTO>).
179 193
180While not mandatory, it is I<highly> recommended to set this callback, as 194While not mandatory, it is I<highly> recommended to set this callback, as
181you will not be notified of errors otherwise. The default simply calls 195you will not be notified of errors otherwise. The default just calls
182C<croak>. 196C<croak>.
183 197
184=item on_read => $cb->($handle) 198=item on_read => $cb->($handle)
185 199
186This sets the default read callback, which is called when data arrives 200This sets the default read callback, which is called when data arrives
… …
191To access (and remove data from) the read buffer, use the C<< ->rbuf >> 205To access (and remove data from) the read buffer, use the C<< ->rbuf >>
192method or access the C<< $handle->{rbuf} >> member directly. Note that you 206method or access the C<< $handle->{rbuf} >> member directly. Note that you
193must not enlarge or modify the read buffer, you can only remove data at 207must not enlarge or modify the read buffer, you can only remove data at
194the beginning from it. 208the beginning from it.
195 209
210You can also call C<< ->push_read (...) >> or any other function that
211modifies the read queue. Or do both. Or ...
212
196When an EOF condition is detected then AnyEvent::Handle will first try to 213When an EOF condition is detected, AnyEvent::Handle will first try to
197feed all the remaining data to the queued callbacks and C<on_read> before 214feed all the remaining data to the queued callbacks and C<on_read> before
198calling the C<on_eof> callback. If no progress can be made, then a fatal 215calling the C<on_eof> callback. If no progress can be made, then a fatal
199error will be raised (with C<$!> set to C<EPIPE>). 216error will be raised (with C<$!> set to C<EPIPE>).
200 217
201Note that, unlike requests in the read queue, an C<on_read> callback 218Note that, unlike requests in the read queue, an C<on_read> callback
… …
219If an EOF condition has been detected but no C<on_eof> callback has been 236If an EOF condition has been detected but no C<on_eof> callback has been
220set, then a fatal error will be raised with C<$!> set to <0>. 237set, then a fatal error will be raised with C<$!> set to <0>.
221 238
222=item on_drain => $cb->($handle) 239=item on_drain => $cb->($handle)
223 240
224This sets the callback that is called when the write buffer becomes empty 241This sets the callback that is called once when the write buffer becomes
225(or when the callback is set and the buffer is empty already). 242empty (and immediately when the handle object is created).
226 243
227To append to the write buffer, use the C<< ->push_write >> method. 244To append to the write buffer, use the C<< ->push_write >> method.
228 245
229This callback is useful when you don't want to put all of your write data 246This callback is useful when you don't want to put all of your write data
230into the queue at once, for example, when you want to write the contents 247into the queue at once, for example, when you want to write the contents
… …
242many seconds pass without a successful read or write on the underlying 259many seconds pass without a successful read or write on the underlying
243file handle (or a call to C<timeout_reset>), the C<on_timeout> callback 260file handle (or a call to C<timeout_reset>), the C<on_timeout> callback
244will be invoked (and if that one is missing, a non-fatal C<ETIMEDOUT> 261will be invoked (and if that one is missing, a non-fatal C<ETIMEDOUT>
245error will be raised). 262error will be raised).
246 263
247There are three variants of the timeouts that work fully independent 264There are three variants of the timeouts that work independently of each
248of each other, for both read and write, just read, and just write: 265other, for both read and write (triggered when nothing was read I<OR>
266written), just read (triggered when nothing was read), and just write:
249C<timeout>, C<rtimeout> and C<wtimeout>, with corresponding callbacks 267C<timeout>, C<rtimeout> and C<wtimeout>, with corresponding callbacks
250C<on_timeout>, C<on_rtimeout> and C<on_wtimeout>, and reset functions 268C<on_timeout>, C<on_rtimeout> and C<on_wtimeout>, and reset functions
251C<timeout_reset>, C<rtimeout_reset>, and C<wtimeout_reset>. 269C<timeout_reset>, C<rtimeout_reset>, and C<wtimeout_reset>.
252 270
253Note that timeout processing is also active when you currently do not have 271Note that timeout processing is active even when you do not have any
254any outstanding read or write requests: If you plan to keep the connection 272outstanding read or write requests: If you plan to keep the connection
255idle then you should disable the timout temporarily or ignore the timeout 273idle then you should disable the timeout temporarily or ignore the
256in the C<on_timeout> callback, in which case AnyEvent::Handle will simply 274timeout in the corresponding C<on_timeout> callback, in which case
257restart the timeout. 275AnyEvent::Handle will simply restart the timeout.
258 276
259Zero (the default) disables this timeout. 277Zero (the default) disables the corresponding timeout.
260 278
261=item on_timeout => $cb->($handle) 279=item on_timeout => $cb->($handle)
280
281=item on_rtimeout => $cb->($handle)
282
283=item on_wtimeout => $cb->($handle)
262 284
263Called whenever the inactivity timeout passes. If you return from this 285Called whenever the inactivity timeout passes. If you return from this
264callback, then the timeout will be reset as if some activity had happened, 286callback, then the timeout will be reset as if some activity had happened,
265so this condition is not fatal in any way. 287so this condition is not fatal in any way.
266 288
… …
274be configured to accept only so-and-so much data that it cannot act on 296be configured to accept only so-and-so much data that it cannot act on
275(for example, when expecting a line, an attacker could send an unlimited 297(for example, when expecting a line, an attacker could send an unlimited
276amount of data without a callback ever being called as long as the line 298amount of data without a callback ever being called as long as the line
277isn't finished). 299isn't finished).
278 300
301=item wbuf_max => <bytes>
302
303If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)
304when the write buffer ever (strictly) exceeds this size. This is useful to
305avoid some forms of denial-of-service attacks.
306
307Although the units of this parameter is bytes, this is the I<raw> number
308of bytes not yet accepted by the kernel. This can make a difference when
309you e.g. use TLS, as TLS typically makes your write data larger (but it
310can also make it smaller due to compression).
311
312As an example of when this limit is useful, take a chat server that sends
313chat messages to a client. If the client does not read those in a timely
314manner then the send buffer in the server would grow unbounded.
315
279=item autocork => <boolean> 316=item autocork => <boolean>
280 317
281When disabled (the default), then C<push_write> will try to immediately 318When disabled (the default), C<push_write> will try to immediately
282write the data to the handle, if possible. This avoids having to register 319write the data to the handle if possible. This avoids having to register
283a write watcher and wait for the next event loop iteration, but can 320a write watcher and wait for the next event loop iteration, but can
284be inefficient if you write multiple small chunks (on the wire, this 321be inefficient if you write multiple small chunks (on the wire, this
285disadvantage is usually avoided by your kernel's nagle algorithm, see 322disadvantage is usually avoided by your kernel's nagle algorithm, see
286C<no_delay>, but this option can save costly syscalls). 323C<no_delay>, but this option can save costly syscalls).
287 324
288When enabled, then writes will always be queued till the next event loop 325When enabled, writes will always be queued till the next event loop
289iteration. This is efficient when you do many small writes per iteration, 326iteration. This is efficient when you do many small writes per iteration,
290but less efficient when you do a single write only per iteration (or when 327but less efficient when you do a single write only per iteration (or when
291the write buffer often is full). It also increases write latency. 328the write buffer often is full). It also increases write latency.
292 329
293=item no_delay => <boolean> 330=item no_delay => <boolean>
… …
297the Nagle algorithm, and usually it is beneficial. 334the Nagle algorithm, and usually it is beneficial.
298 335
299In some situations you want as low a delay as possible, which can be 336In some situations you want as low a delay as possible, which can be
300accomplishd by setting this option to a true value. 337accomplishd by setting this option to a true value.
301 338
302The default is your opertaing system's default behaviour (most likely 339The default is your operating system's default behaviour (most likely
303enabled), this option explicitly enables or disables it, if possible. 340enabled). This option explicitly enables or disables it, if possible.
304 341
305=item keepalive => <boolean> 342=item keepalive => <boolean>
306 343
307Enables (default disable) the SO_KEEPALIVE option on the stream socket: 344Enables (default disable) the SO_KEEPALIVE option on the stream socket:
308normally, TCP connections have no time-out once established, so TCP 345normally, TCP connections have no time-out once established, so TCP
309conenctions, once established, can stay alive forever even when the other 346connections, once established, can stay alive forever even when the other
310side has long gone. TCP keepalives are a cheap way to take down long-lived 347side has long gone. TCP keepalives are a cheap way to take down long-lived
311TCP connections whent he other side becomes unreachable. While the default 348TCP connections when the other side becomes unreachable. While the default
312is OS-dependent, TCP keepalives usually kick in after around two hours, 349is OS-dependent, TCP keepalives usually kick in after around two hours,
313and, if the other side doesn't reply, take down the TCP connection some 10 350and, if the other side doesn't reply, take down the TCP connection some 10
314to 15 minutes later. 351to 15 minutes later.
315 352
316It is harmless to specify this option for file handles that do not support 353It is harmless to specify this option for file handles that do not support
… …
334already have occured on BSD systems), but at least it will protect you 371already have occured on BSD systems), but at least it will protect you
335from most attacks. 372from most attacks.
336 373
337=item read_size => <bytes> 374=item read_size => <bytes>
338 375
339The default read block size (the amount of bytes this module will 376The initial read block size, the number of bytes this module will try
340try to read during each loop iteration, which affects memory 377to read during each loop iteration. Each handle object will consume
341requirements). Default: C<8192>. 378at least this amount of memory for the read buffer as well, so when
379handling many connections watch out for memory requirements). See also
380C<max_read_size>. Default: C<2048>.
381
382=item max_read_size => <bytes>
383
384The maximum read buffer size used by the dynamic adjustment
385algorithm: Each time AnyEvent::Handle can read C<read_size> bytes in
386one go it will double C<read_size> up to the maximum given by this
387option. Default: C<131072> or C<read_size>, whichever is higher.
342 388
343=item low_water_mark => <bytes> 389=item low_water_mark => <bytes>
344 390
345Sets the amount of bytes (default: C<0>) that make up an "empty" write 391Sets the number of bytes (default: C<0>) that make up an "empty" write
346buffer: If the write reaches this size or gets even samller it is 392buffer: If the buffer reaches this size or gets even samller it is
347considered empty. 393considered empty.
348 394
349Sometimes it can be beneficial (for performance reasons) to add data to 395Sometimes it can be beneficial (for performance reasons) to add data to
350the write buffer before it is fully drained, but this is a rare case, as 396the write buffer before it is fully drained, but this is a rare case, as
351the operating system kernel usually buffers data as well, so the default 397the operating system kernel usually buffers data as well, so the default
352is good in almost all cases. 398is good in almost all cases.
353 399
354=item linger => <seconds> 400=item linger => <seconds>
355 401
356If non-zero (default: C<3600>), then the destructor of the 402If this is non-zero (default: C<3600>), the destructor of the
357AnyEvent::Handle object will check whether there is still outstanding 403AnyEvent::Handle object will check whether there is still outstanding
358write data and will install a watcher that will write this data to the 404write data and will install a watcher that will write this data to the
359socket. No errors will be reported (this mostly matches how the operating 405socket. No errors will be reported (this mostly matches how the operating
360system treats outstanding data at socket close time). 406system treats outstanding data at socket close time).
361 407
… …
368A string used to identify the remote site - usually the DNS hostname 414A string used to identify the remote site - usually the DNS hostname
369(I<not> IDN!) used to create the connection, rarely the IP address. 415(I<not> IDN!) used to create the connection, rarely the IP address.
370 416
371Apart from being useful in error messages, this string is also used in TLS 417Apart from being useful in error messages, this string is also used in TLS
372peername verification (see C<verify_peername> in L<AnyEvent::TLS>). This 418peername verification (see C<verify_peername> in L<AnyEvent::TLS>). This
373verification will be skipped when C<peername> is not specified or 419verification will be skipped when C<peername> is not specified or is
374C<undef>. 420C<undef>.
375 421
376=item tls => "accept" | "connect" | Net::SSLeay::SSL object 422=item tls => "accept" | "connect" | Net::SSLeay::SSL object
377 423
378When this parameter is given, it enables TLS (SSL) mode, that means 424When this parameter is given, it enables TLS (SSL) mode, that means
379AnyEvent will start a TLS handshake as soon as the conenction has been 425AnyEvent will start a TLS handshake as soon as the connection has been
380established and will transparently encrypt/decrypt data afterwards. 426established and will transparently encrypt/decrypt data afterwards.
381 427
382All TLS protocol errors will be signalled as C<EPROTO>, with an 428All TLS protocol errors will be signalled as C<EPROTO>, with an
383appropriate error message. 429appropriate error message.
384 430
385TLS mode requires Net::SSLeay to be installed (it will be loaded 431TLS mode requires Net::SSLeay to be installed (it will be loaded
386automatically when you try to create a TLS handle): this module doesn't 432automatically when you try to create a TLS handle): this module doesn't
387have a dependency on that module, so if your module requires it, you have 433have a dependency on that module, so if your module requires it, you have
388to add the dependency yourself. 434to add the dependency yourself. If Net::SSLeay cannot be loaded or is too
435old, you get an C<EPROTO> error.
389 436
390Unlike TCP, TLS has a server and client side: for the TLS server side, use 437Unlike TCP, TLS has a server and client side: for the TLS server side, use
391C<accept>, and for the TLS client side of a connection, use C<connect> 438C<accept>, and for the TLS client side of a connection, use C<connect>
392mode. 439mode.
393 440
… …
404B<IMPORTANT:> since Net::SSLeay "objects" are really only integers, 451B<IMPORTANT:> since Net::SSLeay "objects" are really only integers,
405passing in the wrong integer will lead to certain crash. This most often 452passing in the wrong integer will lead to certain crash. This most often
406happens when one uses a stylish C<< tls => 1 >> and is surprised about the 453happens when one uses a stylish C<< tls => 1 >> and is surprised about the
407segmentation fault. 454segmentation fault.
408 455
409See the C<< ->starttls >> method for when need to start TLS negotiation later. 456Use the C<< ->starttls >> method if you need to start TLS negotiation later.
410 457
411=item tls_ctx => $anyevent_tls 458=item tls_ctx => $anyevent_tls
412 459
413Use the given C<AnyEvent::TLS> object to create the new TLS connection 460Use the given C<AnyEvent::TLS> object to create the new TLS connection
414(unless a connection object was specified directly). If this parameter is 461(unless a connection object was specified directly). If this
415missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>. 462parameter is missing (or C<undef>), then AnyEvent::Handle will use
463C<AnyEvent::Handle::TLS_CTX>.
416 464
417Instead of an object, you can also specify a hash reference with C<< key 465Instead of an object, you can also specify a hash reference with C<< key
418=> value >> pairs. Those will be passed to L<AnyEvent::TLS> to create a 466=> value >> pairs. Those will be passed to L<AnyEvent::TLS> to create a
419new TLS context object. 467new TLS context object.
420 468
… …
429 477
430TLS handshake failures will not cause C<on_error> to be invoked when this 478TLS handshake failures will not cause C<on_error> to be invoked when this
431callback is in effect, instead, the error message will be passed to C<on_starttls>. 479callback is in effect, instead, the error message will be passed to C<on_starttls>.
432 480
433Without this callback, handshake failures lead to C<on_error> being 481Without this callback, handshake failures lead to C<on_error> being
434called, as normal. 482called as usual.
435 483
436Note that you cannot call C<starttls> right again in this callback. If you 484Note that you cannot just call C<starttls> again in this callback. If you
437need to do that, start an zero-second timer instead whose callback can 485need to do that, start an zero-second timer instead whose callback can
438then call C<< ->starttls >> again. 486then call C<< ->starttls >> again.
439 487
440=item on_stoptls => $cb->($handle) 488=item on_stoptls => $cb->($handle)
441 489
… …
489 $self->{connect}[0], 537 $self->{connect}[0],
490 $self->{connect}[1], 538 $self->{connect}[1],
491 sub { 539 sub {
492 my ($fh, $host, $port, $retry) = @_; 540 my ($fh, $host, $port, $retry) = @_;
493 541
542 delete $self->{_connect}; # no longer needed
543
494 if ($fh) { 544 if ($fh) {
495 $self->{fh} = $fh; 545 $self->{fh} = $fh;
496 546
497 delete $self->{_skip_drain_rbuf}; 547 delete $self->{_skip_drain_rbuf};
498 $self->_start; 548 $self->_start;
… …
505 }); 555 });
506 556
507 } else { 557 } else {
508 if ($self->{on_connect_error}) { 558 if ($self->{on_connect_error}) {
509 $self->{on_connect_error}($self, "$!"); 559 $self->{on_connect_error}($self, "$!");
510 $self->destroy; 560 $self->destroy if $self;
511 } else { 561 } else {
512 $self->_error ($!, 1); 562 $self->_error ($!, 1);
513 } 563 }
514 } 564 }
515 }, 565 },
516 sub { 566 sub {
517 local $self->{fh} = $_[0]; 567 local $self->{fh} = $_[0];
518 568
519 $self->{on_prepare} 569 $self->{on_prepare}
520 ? $self->{on_prepare}->($self) 570 ? $self->{on_prepare}->($self)
521 : () 571 : ()
522 } 572 }
523 ); 573 );
524 } 574 }
525 575
… …
531} 581}
532 582
533sub _start { 583sub _start {
534 my ($self) = @_; 584 my ($self) = @_;
535 585
586 # too many clueless people try to use udp and similar sockets
587 # with AnyEvent::Handle, do them a favour.
588 my $type = getsockopt $self->{fh}, Socket::SOL_SOCKET (), Socket::SO_TYPE ();
589 Carp::croak "AnyEvent::Handle: only stream sockets supported, anything else will NOT work!"
590 if Socket::SOCK_STREAM () != (unpack "I", $type) && defined $type;
591
536 AnyEvent::Util::fh_nonblocking $self->{fh}, 1; 592 AnyEvent::Util::fh_nonblocking $self->{fh}, 1;
537 593
538 $self->{_activity} = 594 $self->{_activity} =
539 $self->{_ractivity} = 595 $self->{_ractivity} =
540 $self->{_wactivity} = AE::now; 596 $self->{_wactivity} = AE::now;
541 597
598 $self->{read_size} ||= 2048;
599 $self->{max_read_size} = $self->{read_size}
600 if $self->{read_size} > ($self->{max_read_size} || MAX_READ_SIZE);
601
542 $self->timeout (delete $self->{timeout} ) if $self->{timeout}; 602 $self->timeout (delete $self->{timeout} ) if $self->{timeout};
543 $self->rtimeout (delete $self->{rtimeout} ) if $self->{rtimeout}; 603 $self->rtimeout (delete $self->{rtimeout} ) if $self->{rtimeout};
544 $self->wtimeout (delete $self->{wtimeout} ) if $self->{wtimeout}; 604 $self->wtimeout (delete $self->{wtimeout} ) if $self->{wtimeout};
545 605
546 $self->no_delay (delete $self->{no_delay} ) if exists $self->{no_delay} && $self->{no_delay}; 606 $self->no_delay (delete $self->{no_delay} ) if exists $self->{no_delay} && $self->{no_delay};
… …
549 $self->oobinline (exists $self->{oobinline} ? delete $self->{oobinline} : 1); 609 $self->oobinline (exists $self->{oobinline} ? delete $self->{oobinline} : 1);
550 610
551 $self->starttls (delete $self->{tls}, delete $self->{tls_ctx}) 611 $self->starttls (delete $self->{tls}, delete $self->{tls_ctx})
552 if $self->{tls}; 612 if $self->{tls};
553 613
554 $self->on_drain (delete $self->{on_drain}) if $self->{on_drain}; 614 $self->on_drain (delete $self->{on_drain} ) if $self->{on_drain};
555 615
556 $self->start_read 616 $self->start_read
557 if $self->{on_read} || @{ $self->{_queue} }; 617 if $self->{on_read} || @{ $self->{_queue} };
558 618
559 $self->_drain_wbuf; 619 $self->_drain_wbuf;
… …
566 $message ||= "$!"; 626 $message ||= "$!";
567 627
568 if ($self->{on_error}) { 628 if ($self->{on_error}) {
569 $self->{on_error}($self, $fatal, $message); 629 $self->{on_error}($self, $fatal, $message);
570 $self->destroy if $fatal; 630 $self->destroy if $fatal;
571 } elsif ($self->{fh}) { 631 } elsif ($self->{fh} || $self->{connect}) {
572 $self->destroy; 632 $self->destroy;
573 Carp::croak "AnyEvent::Handle uncaught error: $message"; 633 Carp::croak "AnyEvent::Handle uncaught error: $message";
574 } 634 }
575} 635}
576 636
… …
635=cut 695=cut
636 696
637sub no_delay { 697sub no_delay {
638 $_[0]{no_delay} = $_[1]; 698 $_[0]{no_delay} = $_[1];
639 699
640 eval {
641 local $SIG{__DIE__};
642 setsockopt $_[0]{fh}, Socket::IPPROTO_TCP (), Socket::TCP_NODELAY (), int $_[1] 700 setsockopt $_[0]{fh}, Socket::IPPROTO_TCP (), Socket::TCP_NODELAY (), int $_[1]
643 if $_[0]{fh}; 701 if $_[0]{fh};
644 };
645} 702}
646 703
647=item $handle->keepalive ($boolean) 704=item $handle->keepalive ($boolean)
648 705
649Enables or disables the C<keepalive> setting (see constructor argument of 706Enables or disables the C<keepalive> setting (see constructor argument of
… …
709 766
710Replace the current C<on_stoptls> callback (see the C<on_stoptls> constructor argument). 767Replace the current C<on_stoptls> callback (see the C<on_stoptls> constructor argument).
711 768
712=cut 769=cut
713 770
714sub on_starttls { 771sub on_stoptls {
715 $_[0]{on_stoptls} = $_[1]; 772 $_[0]{on_stoptls} = $_[1];
716} 773}
717 774
718=item $handle->rbuf_max ($max_octets) 775=item $handle->rbuf_max ($max_octets)
719 776
720Configures the C<rbuf_max> setting (C<undef> disables it). 777Configures the C<rbuf_max> setting (C<undef> disables it).
778
779=item $handle->wbuf_max ($max_octets)
780
781Configures the C<wbuf_max> setting (C<undef> disables it).
721 782
722=cut 783=cut
723 784
724sub rbuf_max { 785sub rbuf_max {
725 $_[0]{rbuf_max} = $_[1]; 786 $_[0]{rbuf_max} = $_[1];
726} 787}
727 788
789sub wbuf_max {
790 $_[0]{wbuf_max} = $_[1];
791}
792
728############################################################################# 793#############################################################################
729 794
730=item $handle->timeout ($seconds) 795=item $handle->timeout ($seconds)
731 796
732=item $handle->rtimeout ($seconds) 797=item $handle->rtimeout ($seconds)
733 798
734=item $handle->wtimeout ($seconds) 799=item $handle->wtimeout ($seconds)
735 800
736Configures (or disables) the inactivity timeout. 801Configures (or disables) the inactivity timeout.
802
803The timeout will be checked instantly, so this method might destroy the
804handle before it returns.
737 805
738=item $handle->timeout_reset 806=item $handle->timeout_reset
739 807
740=item $handle->rtimeout_reset 808=item $handle->rtimeout_reset
741 809
… …
758 $_[0]{$on_timeout} = $_[1]; 826 $_[0]{$on_timeout} = $_[1];
759 }; 827 };
760 828
761 *$timeout = sub { 829 *$timeout = sub {
762 my ($self, $new_value) = @_; 830 my ($self, $new_value) = @_;
831
832 $new_value >= 0
833 or Carp::croak "AnyEvent::Handle->$timeout called with negative timeout ($new_value), caught";
763 834
764 $self->{$timeout} = $new_value; 835 $self->{$timeout} = $new_value;
765 delete $self->{$tw}; &$cb; 836 delete $self->{$tw}; &$cb;
766 }; 837 };
767 838
… …
822 893
823The write queue is very simple: you can add data to its end, and 894The write queue is very simple: you can add data to its end, and
824AnyEvent::Handle will automatically try to get rid of it for you. 895AnyEvent::Handle will automatically try to get rid of it for you.
825 896
826When data could be written and the write buffer is shorter then the low 897When data could be written and the write buffer is shorter then the low
827water mark, the C<on_drain> callback will be invoked. 898water mark, the C<on_drain> callback will be invoked once.
828 899
829=over 4 900=over 4
830 901
831=item $handle->on_drain ($cb) 902=item $handle->on_drain ($cb)
832 903
833Sets the C<on_drain> callback or clears it (see the description of 904Sets the C<on_drain> callback or clears it (see the description of
834C<on_drain> in the constructor). 905C<on_drain> in the constructor).
835 906
907This method may invoke callbacks (and therefore the handle might be
908destroyed after it returns).
909
836=cut 910=cut
837 911
838sub on_drain { 912sub on_drain {
839 my ($self, $cb) = @_; 913 my ($self, $cb) = @_;
840 914
… …
844 if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf}); 918 if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf});
845} 919}
846 920
847=item $handle->push_write ($data) 921=item $handle->push_write ($data)
848 922
849Queues the given scalar to be written. You can push as much data as you 923Queues the given scalar to be written. You can push as much data as
850want (only limited by the available memory), as C<AnyEvent::Handle> 924you want (only limited by the available memory and C<wbuf_max>), as
851buffers it independently of the kernel. 925C<AnyEvent::Handle> buffers it independently of the kernel.
926
927This method may invoke callbacks (and therefore the handle might be
928destroyed after it returns).
852 929
853=cut 930=cut
854 931
855sub _drain_wbuf { 932sub _drain_wbuf {
856 my ($self) = @_; 933 my ($self) = @_;
… …
881 $cb->() unless $self->{autocork}; 958 $cb->() unless $self->{autocork};
882 959
883 # if still data left in wbuf, we need to poll 960 # if still data left in wbuf, we need to poll
884 $self->{_ww} = AE::io $self->{fh}, 1, $cb 961 $self->{_ww} = AE::io $self->{fh}, 1, $cb
885 if length $self->{wbuf}; 962 if length $self->{wbuf};
963
964 if (
965 defined $self->{wbuf_max}
966 && $self->{wbuf_max} < length $self->{wbuf}
967 ) {
968 $self->_error (Errno::ENOSPC, 1), return;
969 }
886 }; 970 };
887} 971}
888 972
889our %WH; 973our %WH;
890 974
… …
902 @_ = ($WH{$type} ||= _load_func "$type\::anyevent_write_type" 986 @_ = ($WH{$type} ||= _load_func "$type\::anyevent_write_type"
903 or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::push_write") 987 or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::push_write")
904 ->($self, @_); 988 ->($self, @_);
905 } 989 }
906 990
991 # we downgrade here to avoid hard-to-track-down bugs,
992 # and diagnose the problem earlier and better.
993
907 if ($self->{tls}) { 994 if ($self->{tls}) {
908 $self->{_tls_wbuf} .= $_[0]; 995 utf8::downgrade $self->{_tls_wbuf} .= $_[0];
909 &_dotls ($self) if $self->{fh}; 996 &_dotls ($self) if $self->{fh};
910 } else { 997 } else {
911 $self->{wbuf} .= $_[0]; 998 utf8::downgrade $self->{wbuf} .= $_[0];
912 $self->_drain_wbuf if $self->{fh}; 999 $self->_drain_wbuf if $self->{fh};
913 } 1000 }
914} 1001}
915 1002
916=item $handle->push_write (type => @args) 1003=item $handle->push_write (type => @args)
917 1004
918Instead of formatting your data yourself, you can also let this module 1005Instead of formatting your data yourself, you can also let this module
919do the job by specifying a type and type-specific arguments. You 1006do the job by specifying a type and type-specific arguments. You
920can also specify the (fully qualified) name of a package, in which 1007can also specify the (fully qualified) name of a package, in which
921case AnyEvent tries to load the package and then expects to find the 1008case AnyEvent tries to load the package and then expects to find the
922C<anyevent_read_type> function inside (see "custom write types", below). 1009C<anyevent_write_type> function inside (see "custom write types", below).
923 1010
924Predefined types are (if you have ideas for additional types, feel free to 1011Predefined types are (if you have ideas for additional types, feel free to
925drop by and tell us): 1012drop by and tell us):
926 1013
927=over 4 1014=over 4
… …
1007=cut 1094=cut
1008 1095
1009register_write_type storable => sub { 1096register_write_type storable => sub {
1010 my ($self, $ref) = @_; 1097 my ($self, $ref) = @_;
1011 1098
1012 require Storable; 1099 require Storable unless $Storable::VERSION;
1013 1100
1014 pack "w/a*", Storable::nfreeze ($ref) 1101 pack "w/a*", Storable::nfreeze ($ref)
1015}; 1102};
1016 1103
1017=back 1104=back
… …
1022before it was actually written. One way to do that is to replace your 1109before it was actually written. One way to do that is to replace your
1023C<on_drain> handler by a callback that shuts down the socket (and set 1110C<on_drain> handler by a callback that shuts down the socket (and set
1024C<low_water_mark> to C<0>). This method is a shorthand for just that, and 1111C<low_water_mark> to C<0>). This method is a shorthand for just that, and
1025replaces the C<on_drain> callback with: 1112replaces the C<on_drain> callback with:
1026 1113
1027 sub { shutdown $_[0]{fh}, 1 } # for push_shutdown 1114 sub { shutdown $_[0]{fh}, 1 }
1028 1115
1029This simply shuts down the write side and signals an EOF condition to the 1116This simply shuts down the write side and signals an EOF condition to the
1030the peer. 1117the peer.
1031 1118
1032You can rely on the normal read queue and C<on_eof> handling 1119You can rely on the normal read queue and C<on_eof> handling
1033afterwards. This is the cleanest way to close a connection. 1120afterwards. This is the cleanest way to close a connection.
1121
1122This method may invoke callbacks (and therefore the handle might be
1123destroyed after it returns).
1034 1124
1035=cut 1125=cut
1036 1126
1037sub push_shutdown { 1127sub push_shutdown {
1038 my ($self) = @_; 1128 my ($self) = @_;
… …
1051 1141
1052Whenever the given C<type> is used, C<push_write> will the function with 1142Whenever the given C<type> is used, C<push_write> will the function with
1053the handle object and the remaining arguments. 1143the handle object and the remaining arguments.
1054 1144
1055The function is supposed to return a single octet string that will be 1145The function is supposed to return a single octet string that will be
1056appended to the write buffer, so you cna mentally treat this function as a 1146appended to the write buffer, so you can mentally treat this function as a
1057"arguments to on-the-wire-format" converter. 1147"arguments to on-the-wire-format" converter.
1058 1148
1059Example: implement a custom write type C<join> that joins the remaining 1149Example: implement a custom write type C<join> that joins the remaining
1060arguments using the first one. 1150arguments using the first one.
1061 1151
… …
1088ways, the "simple" way, using only C<on_read> and the "complex" way, using 1178ways, the "simple" way, using only C<on_read> and the "complex" way, using
1089a queue. 1179a queue.
1090 1180
1091In the simple case, you just install an C<on_read> callback and whenever 1181In the simple case, you just install an C<on_read> callback and whenever
1092new data arrives, it will be called. You can then remove some data (if 1182new data arrives, it will be called. You can then remove some data (if
1093enough is there) from the read buffer (C<< $handle->rbuf >>). Or you cna 1183enough is there) from the read buffer (C<< $handle->rbuf >>). Or you can
1094leave the data there if you want to accumulate more (e.g. when only a 1184leave the data there if you want to accumulate more (e.g. when only a
1095partial message has been received so far). 1185partial message has been received so far), or change the read queue with
1186e.g. C<push_read>.
1096 1187
1097In the more complex case, you want to queue multiple callbacks. In this 1188In the more complex case, you want to queue multiple callbacks. In this
1098case, AnyEvent::Handle will call the first queued callback each time new 1189case, AnyEvent::Handle will call the first queued callback each time new
1099data arrives (also the first time it is queued) and removes it when it has 1190data arrives (also the first time it is queued) and remove it when it has
1100done its job (see C<push_read>, below). 1191done its job (see C<push_read>, below).
1101 1192
1102This way you can, for example, push three line-reads, followed by reading 1193This way you can, for example, push three line-reads, followed by reading
1103a chunk of data, and AnyEvent::Handle will execute them in order. 1194a chunk of data, and AnyEvent::Handle will execute them in order.
1104 1195
… …
1235 1326
1236This replaces the currently set C<on_read> callback, or clears it (when 1327This replaces the currently set C<on_read> callback, or clears it (when
1237the new callback is C<undef>). See the description of C<on_read> in the 1328the new callback is C<undef>). See the description of C<on_read> in the
1238constructor. 1329constructor.
1239 1330
1331This method may invoke callbacks (and therefore the handle might be
1332destroyed after it returns).
1333
1240=cut 1334=cut
1241 1335
1242sub on_read { 1336sub on_read {
1243 my ($self, $cb) = @_; 1337 my ($self, $cb) = @_;
1244 1338
… …
1246 $self->_drain_rbuf if $cb; 1340 $self->_drain_rbuf if $cb;
1247} 1341}
1248 1342
1249=item $handle->rbuf 1343=item $handle->rbuf
1250 1344
1251Returns the read buffer (as a modifiable lvalue). 1345Returns the read buffer (as a modifiable lvalue). You can also access the
1346read buffer directly as the C<< ->{rbuf} >> member, if you want (this is
1347much faster, and no less clean).
1252 1348
1253You can access the read buffer directly as the C<< ->{rbuf} >> 1349The only operation allowed on the read buffer (apart from looking at it)
1254member, if you want. However, the only operation allowed on the 1350is removing data from its beginning. Otherwise modifying or appending to
1255read buffer (apart from looking at it) is removing data from its 1351it is not allowed and will lead to hard-to-track-down bugs.
1256beginning. Otherwise modifying or appending to it is not allowed and will
1257lead to hard-to-track-down bugs.
1258 1352
1259NOTE: The read buffer should only be used or modified if the C<on_read>, 1353NOTE: The read buffer should only be used or modified in the C<on_read>
1260C<push_read> or C<unshift_read> methods are used. The other read methods 1354callback or when C<push_read> or C<unshift_read> are used with a single
1261automatically manage the read buffer. 1355callback (i.e. untyped). Typed C<push_read> and C<unshift_read> methods
1356will manage the read buffer on their own.
1262 1357
1263=cut 1358=cut
1264 1359
1265sub rbuf : lvalue { 1360sub rbuf : lvalue {
1266 $_[0]{rbuf} 1361 $_[0]{rbuf}
… …
1283 1378
1284If enough data was available, then the callback must remove all data it is 1379If enough data was available, then the callback must remove all data it is
1285interested in (which can be none at all) and return a true value. After returning 1380interested in (which can be none at all) and return a true value. After returning
1286true, it will be removed from the queue. 1381true, it will be removed from the queue.
1287 1382
1383These methods may invoke callbacks (and therefore the handle might be
1384destroyed after it returns).
1385
1288=cut 1386=cut
1289 1387
1290our %RH; 1388our %RH;
1291 1389
1292sub register_read_type($$) { 1390sub register_read_type($$) {
… …
1314 my $cb = pop; 1412 my $cb = pop;
1315 1413
1316 if (@_) { 1414 if (@_) {
1317 my $type = shift; 1415 my $type = shift;
1318 1416
1417 $cb = ($RH{$type} ||= _load_func "$type\::anyevent_read_type"
1319 $cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::unshift_read") 1418 or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::unshift_read")
1320 ->($self, $cb, @_); 1419 ->($self, $cb, @_);
1321 } 1420 }
1322 1421
1323 unshift @{ $self->{_queue} }, $cb; 1422 unshift @{ $self->{_queue} }, $cb;
1324 $self->_drain_rbuf; 1423 $self->_drain_rbuf;
… …
1346data. 1445data.
1347 1446
1348Example: read 2 bytes. 1447Example: read 2 bytes.
1349 1448
1350 $handle->push_read (chunk => 2, sub { 1449 $handle->push_read (chunk => 2, sub {
1351 warn "yay ", unpack "H*", $_[1]; 1450 say "yay " . unpack "H*", $_[1];
1352 }); 1451 });
1353 1452
1354=cut 1453=cut
1355 1454
1356register_read_type chunk => sub { 1455register_read_type chunk => sub {
… …
1390 if (@_ < 3) { 1489 if (@_ < 3) {
1391 # this is more than twice as fast as the generic code below 1490 # this is more than twice as fast as the generic code below
1392 sub { 1491 sub {
1393 $_[0]{rbuf} =~ s/^([^\015\012]*)(\015?\012)// or return; 1492 $_[0]{rbuf} =~ s/^([^\015\012]*)(\015?\012)// or return;
1394 1493
1395 $cb->($_[0], $1, $2); 1494 $cb->($_[0], "$1", "$2");
1396 1 1495 1
1397 } 1496 }
1398 } else { 1497 } else {
1399 $eol = quotemeta $eol unless ref $eol; 1498 $eol = quotemeta $eol unless ref $eol;
1400 $eol = qr|^(.*?)($eol)|s; 1499 $eol = qr|^(.*?)($eol)|s;
1401 1500
1402 sub { 1501 sub {
1403 $_[0]{rbuf} =~ s/$eol// or return; 1502 $_[0]{rbuf} =~ s/$eol// or return;
1404 1503
1405 $cb->($_[0], $1, $2); 1504 $cb->($_[0], "$1", "$2");
1406 1 1505 1
1407 } 1506 }
1408 } 1507 }
1409}; 1508};
1410 1509
… …
1432the receive buffer when neither C<$accept> nor C<$reject> match, 1531the receive buffer when neither C<$accept> nor C<$reject> match,
1433and everything preceding and including the match will be accepted 1532and everything preceding and including the match will be accepted
1434unconditionally. This is useful to skip large amounts of data that you 1533unconditionally. This is useful to skip large amounts of data that you
1435know cannot be matched, so that the C<$accept> or C<$reject> regex do not 1534know cannot be matched, so that the C<$accept> or C<$reject> regex do not
1436have to start matching from the beginning. This is purely an optimisation 1535have to start matching from the beginning. This is purely an optimisation
1437and is usually worth only when you expect more than a few kilobytes. 1536and is usually worth it only when you expect more than a few kilobytes.
1438 1537
1439Example: expect a http header, which ends at C<\015\012\015\012>. Since we 1538Example: expect a http header, which ends at C<\015\012\015\012>. Since we
1440expect the header to be very large (it isn't in practise, but...), we use 1539expect the header to be very large (it isn't in practice, but...), we use
1441a skip regex to skip initial portions. The skip regex is tricky in that 1540a skip regex to skip initial portions. The skip regex is tricky in that
1442it only accepts something not ending in either \015 or \012, as these are 1541it only accepts something not ending in either \015 or \012, as these are
1443required for the accept regex. 1542required for the accept regex.
1444 1543
1445 $handle->push_read (regex => 1544 $handle->push_read (regex =>
… …
1458 1557
1459 sub { 1558 sub {
1460 # accept 1559 # accept
1461 if ($$rbuf =~ $accept) { 1560 if ($$rbuf =~ $accept) {
1462 $data .= substr $$rbuf, 0, $+[0], ""; 1561 $data .= substr $$rbuf, 0, $+[0], "";
1463 $cb->($self, $data); 1562 $cb->($_[0], $data);
1464 return 1; 1563 return 1;
1465 } 1564 }
1466 1565
1467 # reject 1566 # reject
1468 if ($reject && $$rbuf =~ $reject) { 1567 if ($reject && $$rbuf =~ $reject) {
1469 $self->_error (Errno::EBADMSG); 1568 $_[0]->_error (Errno::EBADMSG);
1470 } 1569 }
1471 1570
1472 # skip 1571 # skip
1473 if ($skip && $$rbuf =~ $skip) { 1572 if ($skip && $$rbuf =~ $skip) {
1474 $data .= substr $$rbuf, 0, $+[0], ""; 1573 $data .= substr $$rbuf, 0, $+[0], "";
… …
1490 my ($self, $cb) = @_; 1589 my ($self, $cb) = @_;
1491 1590
1492 sub { 1591 sub {
1493 unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) { 1592 unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
1494 if ($_[0]{rbuf} =~ /[^0-9]/) { 1593 if ($_[0]{rbuf} =~ /[^0-9]/) {
1495 $self->_error (Errno::EBADMSG); 1594 $_[0]->_error (Errno::EBADMSG);
1496 } 1595 }
1497 return; 1596 return;
1498 } 1597 }
1499 1598
1500 my $len = $1; 1599 my $len = $1;
1501 1600
1502 $self->unshift_read (chunk => $len, sub { 1601 $_[0]->unshift_read (chunk => $len, sub {
1503 my $string = $_[1]; 1602 my $string = $_[1];
1504 $_[0]->unshift_read (chunk => 1, sub { 1603 $_[0]->unshift_read (chunk => 1, sub {
1505 if ($_[1] eq ",") { 1604 if ($_[1] eq ",") {
1506 $cb->($_[0], $string); 1605 $cb->($_[0], $string);
1507 } else { 1606 } else {
1508 $self->_error (Errno::EBADMSG); 1607 $_[0]->_error (Errno::EBADMSG);
1509 } 1608 }
1510 }); 1609 });
1511 }); 1610 });
1512 1611
1513 1 1612 1
… …
1586 1685
1587 my $data; 1686 my $data;
1588 my $rbuf = \$self->{rbuf}; 1687 my $rbuf = \$self->{rbuf};
1589 1688
1590 sub { 1689 sub {
1591 my $ref = eval { $json->incr_parse ($self->{rbuf}) }; 1690 my $ref = eval { $json->incr_parse ($_[0]{rbuf}) };
1592 1691
1593 if ($ref) { 1692 if ($ref) {
1594 $self->{rbuf} = $json->incr_text; 1693 $_[0]{rbuf} = $json->incr_text;
1595 $json->incr_text = ""; 1694 $json->incr_text = "";
1596 $cb->($self, $ref); 1695 $cb->($_[0], $ref);
1597 1696
1598 1 1697 1
1599 } elsif ($@) { 1698 } elsif ($@) {
1600 # error case 1699 # error case
1601 $json->incr_skip; 1700 $json->incr_skip;
1602 1701
1603 $self->{rbuf} = $json->incr_text; 1702 $_[0]{rbuf} = $json->incr_text;
1604 $json->incr_text = ""; 1703 $json->incr_text = "";
1605 1704
1606 $self->_error (Errno::EBADMSG); 1705 $_[0]->_error (Errno::EBADMSG);
1607 1706
1608 () 1707 ()
1609 } else { 1708 } else {
1610 $self->{rbuf} = ""; 1709 $_[0]{rbuf} = "";
1611 1710
1612 () 1711 ()
1613 } 1712 }
1614 } 1713 }
1615}; 1714};
… …
1625=cut 1724=cut
1626 1725
1627register_read_type storable => sub { 1726register_read_type storable => sub {
1628 my ($self, $cb) = @_; 1727 my ($self, $cb) = @_;
1629 1728
1630 require Storable; 1729 require Storable unless $Storable::VERSION;
1631 1730
1632 sub { 1731 sub {
1633 # when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method 1732 # when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
1634 defined (my $len = eval { unpack "w", $_[0]{rbuf} }) 1733 defined (my $len = eval { unpack "w", $_[0]{rbuf} })
1635 or return; 1734 or return;
… …
1638 1737
1639 # bypass unshift if we already have the remaining chunk 1738 # bypass unshift if we already have the remaining chunk
1640 if ($format + $len <= length $_[0]{rbuf}) { 1739 if ($format + $len <= length $_[0]{rbuf}) {
1641 my $data = substr $_[0]{rbuf}, $format, $len; 1740 my $data = substr $_[0]{rbuf}, $format, $len;
1642 substr $_[0]{rbuf}, 0, $format + $len, ""; 1741 substr $_[0]{rbuf}, 0, $format + $len, "";
1742
1643 $cb->($_[0], Storable::thaw ($data)); 1743 eval { $cb->($_[0], Storable::thaw ($data)); 1 }
1744 or return $_[0]->_error (Errno::EBADMSG);
1644 } else { 1745 } else {
1645 # remove prefix 1746 # remove prefix
1646 substr $_[0]{rbuf}, 0, $format, ""; 1747 substr $_[0]{rbuf}, 0, $format, "";
1647 1748
1648 # read remaining chunk 1749 # read remaining chunk
1649 $_[0]->unshift_read (chunk => $len, sub { 1750 $_[0]->unshift_read (chunk => $len, sub {
1650 if (my $ref = eval { Storable::thaw ($_[1]) }) { 1751 eval { $cb->($_[0], Storable::thaw ($_[1])); 1 }
1651 $cb->($_[0], $ref);
1652 } else {
1653 $self->_error (Errno::EBADMSG); 1752 or $_[0]->_error (Errno::EBADMSG);
1654 }
1655 }); 1753 });
1656 } 1754 }
1657 1755
1658 1 1756 1
1659 } 1757 }
… …
1696Note that AnyEvent::Handle will automatically C<start_read> for you when 1794Note that AnyEvent::Handle will automatically C<start_read> for you when
1697you change the C<on_read> callback or push/unshift a read callback, and it 1795you change the C<on_read> callback or push/unshift a read callback, and it
1698will automatically C<stop_read> for you when neither C<on_read> is set nor 1796will automatically C<stop_read> for you when neither C<on_read> is set nor
1699there are any read requests in the queue. 1797there are any read requests in the queue.
1700 1798
1701These methods will have no effect when in TLS mode (as TLS doesn't support 1799In older versions of this module (<= 5.3), these methods had no effect,
1702half-duplex connections). 1800as TLS does not support half-duplex connections. In current versions they
1801work as expected, as this behaviour is required to avoid certain resource
1802attacks, where the program would be forced to read (and buffer) arbitrary
1803amounts of data before being able to send some data. The drawback is that
1804some readings of the the SSL/TLS specifications basically require this
1805attack to be working, as SSL/TLS implementations might stall sending data
1806during a rehandshake.
1807
1808As a guideline, during the initial handshake, you should not stop reading,
1809and as a client, it might cause problems, depending on your application.
1703 1810
1704=cut 1811=cut
1705 1812
1706sub stop_read { 1813sub stop_read {
1707 my ($self) = @_; 1814 my ($self) = @_;
1708 1815
1709 delete $self->{_rw} unless $self->{tls}; 1816 delete $self->{_rw};
1710} 1817}
1711 1818
1712sub start_read { 1819sub start_read {
1713 my ($self) = @_; 1820 my ($self) = @_;
1714 1821
1715 unless ($self->{_rw} || $self->{_eof}) { 1822 unless ($self->{_rw} || $self->{_eof} || !$self->{fh}) {
1716 Scalar::Util::weaken $self; 1823 Scalar::Util::weaken $self;
1717 1824
1718 $self->{_rw} = AE::io $self->{fh}, 0, sub { 1825 $self->{_rw} = AE::io $self->{fh}, 0, sub {
1719 my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf}); 1826 my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf});
1720 my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf; 1827 my $len = sysread $self->{fh}, $$rbuf, $self->{read_size}, length $$rbuf;
1721 1828
1722 if ($len > 0) { 1829 if ($len > 0) {
1723 $self->{_activity} = $self->{_ractivity} = AE::now; 1830 $self->{_activity} = $self->{_ractivity} = AE::now;
1724 1831
1725 if ($self->{tls}) { 1832 if ($self->{tls}) {
… …
1728 &_dotls ($self); 1835 &_dotls ($self);
1729 } else { 1836 } else {
1730 $self->_drain_rbuf; 1837 $self->_drain_rbuf;
1731 } 1838 }
1732 1839
1840 if ($len == $self->{read_size}) {
1841 $self->{read_size} *= 2;
1842 $self->{read_size} = $self->{max_read_size} || MAX_READ_SIZE
1843 if $self->{read_size} > ($self->{max_read_size} || MAX_READ_SIZE);
1844 }
1845
1733 } elsif (defined $len) { 1846 } elsif (defined $len) {
1734 delete $self->{_rw}; 1847 delete $self->{_rw};
1735 $self->{_eof} = 1; 1848 $self->{_eof} = 1;
1736 $self->_drain_rbuf; 1849 $self->_drain_rbuf;
1737 1850
… …
1749 my ($self, $err) = @_; 1862 my ($self, $err) = @_;
1750 1863
1751 return $self->_error ($!, 1) 1864 return $self->_error ($!, 1)
1752 if $err == Net::SSLeay::ERROR_SYSCALL (); 1865 if $err == Net::SSLeay::ERROR_SYSCALL ();
1753 1866
1754 my $err =Net::SSLeay::ERR_error_string (Net::SSLeay::ERR_get_error ()); 1867 my $err = Net::SSLeay::ERR_error_string (Net::SSLeay::ERR_get_error ());
1755 1868
1756 # reduce error string to look less scary 1869 # reduce error string to look less scary
1757 $err =~ s/^error:[0-9a-fA-F]{8}:[^:]+:([^:]+):/\L$1: /; 1870 $err =~ s/^error:[0-9a-fA-F]{8}:[^:]+:([^:]+):/\L$1: /;
1758 1871
1759 if ($self->{_on_starttls}) { 1872 if ($self->{_on_starttls}) {
… …
1813 && ($tmp != $ERROR_SYSCALL || $!); 1926 && ($tmp != $ERROR_SYSCALL || $!);
1814 1927
1815 while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) { 1928 while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) {
1816 $self->{wbuf} .= $tmp; 1929 $self->{wbuf} .= $tmp;
1817 $self->_drain_wbuf; 1930 $self->_drain_wbuf;
1931 $self->{tls} or return; # tls session might have gone away in callback
1818 } 1932 }
1819 1933
1820 $self->{_on_starttls} 1934 $self->{_on_starttls}
1821 and Net::SSLeay::state ($self->{tls}) == Net::SSLeay::ST_OK () 1935 and Net::SSLeay::state ($self->{tls}) == Net::SSLeay::ST_OK ()
1822 and (delete $self->{_on_starttls})->($self, 1, "TLS/SSL connection established"); 1936 and (delete $self->{_on_starttls})->($self, 1, "TLS/SSL connection established");
… …
1824 1938
1825=item $handle->starttls ($tls[, $tls_ctx]) 1939=item $handle->starttls ($tls[, $tls_ctx])
1826 1940
1827Instead of starting TLS negotiation immediately when the AnyEvent::Handle 1941Instead of starting TLS negotiation immediately when the AnyEvent::Handle
1828object is created, you can also do that at a later time by calling 1942object is created, you can also do that at a later time by calling
1829C<starttls>. 1943C<starttls>. See the C<tls> constructor argument for general info.
1830 1944
1831Starting TLS is currently an asynchronous operation - when you push some 1945Starting TLS is currently an asynchronous operation - when you push some
1832write data and then call C<< ->starttls >> then TLS negotiation will start 1946write data and then call C<< ->starttls >> then TLS negotiation will start
1833immediately, after which the queued write data is then sent. 1947immediately, after which the queued write data is then sent. This might
1948change in future versions, so best make sure you have no outstanding write
1949data when calling this method.
1834 1950
1835The first argument is the same as the C<tls> constructor argument (either 1951The first argument is the same as the C<tls> constructor argument (either
1836C<"connect">, C<"accept"> or an existing Net::SSLeay object). 1952C<"connect">, C<"accept"> or an existing Net::SSLeay object).
1837 1953
1838The second argument is the optional C<AnyEvent::TLS> object that is used 1954The second argument is the optional C<AnyEvent::TLS> object that is used
… …
1844context in C<< $handle->{tls_ctx} >> after this call and can be used or 1960context in C<< $handle->{tls_ctx} >> after this call and can be used or
1845changed to your liking. Note that the handshake might have already started 1961changed to your liking. Note that the handshake might have already started
1846when this function returns. 1962when this function returns.
1847 1963
1848Due to bugs in OpenSSL, it might or might not be possible to do multiple 1964Due to bugs in OpenSSL, it might or might not be possible to do multiple
1849handshakes on the same stream. Best do not attempt to use the stream after 1965handshakes on the same stream. It is best to not attempt to use the
1850stopping TLS. 1966stream after stopping TLS.
1967
1968This method may invoke callbacks (and therefore the handle might be
1969destroyed after it returns).
1851 1970
1852=cut 1971=cut
1853 1972
1854our %TLS_CACHE; #TODO not yet documented, should we? 1973our %TLS_CACHE; #TODO not yet documented, should we?
1855 1974
… …
1857 my ($self, $tls, $ctx) = @_; 1976 my ($self, $tls, $ctx) = @_;
1858 1977
1859 Carp::croak "It is an error to call starttls on an AnyEvent::Handle object while TLS is already active, caught" 1978 Carp::croak "It is an error to call starttls on an AnyEvent::Handle object while TLS is already active, caught"
1860 if $self->{tls}; 1979 if $self->{tls};
1861 1980
1981 unless (defined $AnyEvent::TLS::VERSION) {
1982 eval {
1983 require Net::SSLeay;
1984 require AnyEvent::TLS;
1985 1
1986 } or return $self->_error (Errno::EPROTO, 1, "TLS support not available on this system");
1987 }
1988
1862 $self->{tls} = $tls; 1989 $self->{tls} = $tls;
1863 $self->{tls_ctx} = $ctx if @_ > 2; 1990 $self->{tls_ctx} = $ctx if @_ > 2;
1864 1991
1865 return unless $self->{fh}; 1992 return unless $self->{fh};
1866 1993
1867 require Net::SSLeay;
1868
1869 $ERROR_SYSCALL = Net::SSLeay::ERROR_SYSCALL (); 1994 $ERROR_SYSCALL = Net::SSLeay::ERROR_SYSCALL ();
1870 $ERROR_WANT_READ = Net::SSLeay::ERROR_WANT_READ (); 1995 $ERROR_WANT_READ = Net::SSLeay::ERROR_WANT_READ ();
1871 1996
1872 $tls = delete $self->{tls}; 1997 $tls = delete $self->{tls};
1873 $ctx = $self->{tls_ctx}; 1998 $ctx = $self->{tls_ctx};
1874 1999
1875 local $Carp::CarpLevel = 1; # skip ourselves when creating a new context or session 2000 local $Carp::CarpLevel = 1; # skip ourselves when creating a new context or session
1876 2001
1877 if ("HASH" eq ref $ctx) { 2002 if ("HASH" eq ref $ctx) {
1878 require AnyEvent::TLS;
1879
1880 if ($ctx->{cache}) { 2003 if ($ctx->{cache}) {
1881 my $key = $ctx+0; 2004 my $key = $ctx+0;
1882 $ctx = $TLS_CACHE{$key} ||= new AnyEvent::TLS %$ctx; 2005 $ctx = $TLS_CACHE{$key} ||= new AnyEvent::TLS %$ctx;
1883 } else { 2006 } else {
1884 $ctx = new AnyEvent::TLS %$ctx; 2007 $ctx = new AnyEvent::TLS %$ctx;
… …
1906 Net::SSLeay::CTX_set_mode ($tls, 1|2); 2029 Net::SSLeay::CTX_set_mode ($tls, 1|2);
1907 2030
1908 $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); 2031 $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1909 $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); 2032 $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1910 2033
1911 Net::SSLeay::BIO_write ($self->{_rbio}, delete $self->{rbuf}); 2034 Net::SSLeay::BIO_write ($self->{_rbio}, $self->{rbuf});
2035 $self->{rbuf} = "";
1912 2036
1913 Net::SSLeay::set_bio ($tls, $self->{_rbio}, $self->{_wbio}); 2037 Net::SSLeay::set_bio ($tls, $self->{_rbio}, $self->{_wbio});
1914 2038
1915 $self->{_on_starttls} = sub { $_[0]{on_starttls}(@_) } 2039 $self->{_on_starttls} = sub { $_[0]{on_starttls}(@_) }
1916 if $self->{on_starttls}; 2040 if $self->{on_starttls};
… …
1921 2045
1922=item $handle->stoptls 2046=item $handle->stoptls
1923 2047
1924Shuts down the SSL connection - this makes a proper EOF handshake by 2048Shuts down the SSL connection - this makes a proper EOF handshake by
1925sending a close notify to the other side, but since OpenSSL doesn't 2049sending a close notify to the other side, but since OpenSSL doesn't
1926support non-blocking shut downs, it is not guarenteed that you can re-use 2050support non-blocking shut downs, it is not guaranteed that you can re-use
1927the stream afterwards. 2051the stream afterwards.
2052
2053This method may invoke callbacks (and therefore the handle might be
2054destroyed after it returns).
1928 2055
1929=cut 2056=cut
1930 2057
1931sub stoptls { 2058sub stoptls {
1932 my ($self) = @_; 2059 my ($self) = @_;
1933 2060
1934 if ($self->{tls}) { 2061 if ($self->{tls} && $self->{fh}) {
1935 Net::SSLeay::shutdown ($self->{tls}); 2062 Net::SSLeay::shutdown ($self->{tls});
1936 2063
1937 &_dotls; 2064 &_dotls;
1938 2065
1939# # we don't give a shit. no, we do, but we can't. no...#d# 2066# # we don't give a shit. no, we do, but we can't. no...#d#
… …
1951 if $self->{tls} > 0; 2078 if $self->{tls} > 0;
1952 2079
1953 delete @$self{qw(_rbio _wbio _tls_wbuf _on_starttls)}; 2080 delete @$self{qw(_rbio _wbio _tls_wbuf _on_starttls)};
1954} 2081}
1955 2082
2083=item $handle->resettls
2084
2085This rarely-used method simply resets and TLS state on the handle, usually
2086causing data loss.
2087
2088One case where it may be useful is when you want to skip over the data in
2089the stream but you are not interested in interpreting it, so data loss is
2090no concern.
2091
2092=cut
2093
2094*resettls = \&_freetls;
2095
1956sub DESTROY { 2096sub DESTROY {
1957 my ($self) = @_; 2097 my ($self) = @_;
1958 2098
1959 &_freetls; 2099 &_freetls;
1960 2100
… …
1969 push @linger, AE::io $fh, 1, sub { 2109 push @linger, AE::io $fh, 1, sub {
1970 my $len = syswrite $fh, $wbuf, length $wbuf; 2110 my $len = syswrite $fh, $wbuf, length $wbuf;
1971 2111
1972 if ($len > 0) { 2112 if ($len > 0) {
1973 substr $wbuf, 0, $len, ""; 2113 substr $wbuf, 0, $len, "";
1974 } else { 2114 } elsif (defined $len || ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK)) {
1975 @linger = (); # end 2115 @linger = (); # end
1976 } 2116 }
1977 }; 2117 };
1978 push @linger, AE::timer $linger, 0, sub { 2118 push @linger, AE::timer $linger, 0, sub {
1979 @linger = (); 2119 @linger = ();
… …
2016 2156
2017sub AnyEvent::Handle::destroyed::AUTOLOAD { 2157sub AnyEvent::Handle::destroyed::AUTOLOAD {
2018 #nop 2158 #nop
2019} 2159}
2020 2160
2161=item $handle->destroyed
2162
2163Returns false as long as the handle hasn't been destroyed by a call to C<<
2164->destroy >>, true otherwise.
2165
2166Can be useful to decide whether the handle is still valid after some
2167callback possibly destroyed the handle. For example, C<< ->push_write >>,
2168C<< ->starttls >> and other methods can call user callbacks, which in turn
2169can destroy the handle, so work can be avoided by checking sometimes:
2170
2171 $hdl->starttls ("accept");
2172 return if $hdl->destroyed;
2173 $hdl->push_write (...
2174
2175Note that the call to C<push_write> will silently be ignored if the handle
2176has been destroyed, so often you can just ignore the possibility of the
2177handle being destroyed.
2178
2179=cut
2180
2181sub destroyed { 0 }
2182sub AnyEvent::Handle::destroyed::destroyed { 1 }
2183
2021=item AnyEvent::Handle::TLS_CTX 2184=item AnyEvent::Handle::TLS_CTX
2022 2185
2023This function creates and returns the AnyEvent::TLS object used by default 2186This function creates and returns the AnyEvent::TLS object used by default
2024for TLS mode. 2187for TLS mode.
2025 2188
… …
2052 2215
2053It is only safe to "forget" the reference inside EOF or error callbacks, 2216It is only safe to "forget" the reference inside EOF or error callbacks,
2054from within all other callbacks, you need to explicitly call the C<< 2217from within all other callbacks, you need to explicitly call the C<<
2055->destroy >> method. 2218->destroy >> method.
2056 2219
2220=item Why is my C<on_eof> callback never called?
2221
2222Probably because your C<on_error> callback is being called instead: When
2223you have outstanding requests in your read queue, then an EOF is
2224considered an error as you clearly expected some data.
2225
2226To avoid this, make sure you have an empty read queue whenever your handle
2227is supposed to be "idle" (i.e. connection closes are O.K.). You can set
2228an C<on_read> handler that simply pushes the first read requests in the
2229queue.
2230
2231See also the next question, which explains this in a bit more detail.
2232
2233=item How can I serve requests in a loop?
2234
2235Most protocols consist of some setup phase (authentication for example)
2236followed by a request handling phase, where the server waits for requests
2237and handles them, in a loop.
2238
2239There are two important variants: The first (traditional, better) variant
2240handles requests until the server gets some QUIT command, causing it to
2241close the connection first (highly desirable for a busy TCP server). A
2242client dropping the connection is an error, which means this variant can
2243detect an unexpected detection close.
2244
2245To handle this case, always make sure you have a non-empty read queue, by
2246pushing the "read request start" handler on it:
2247
2248 # we assume a request starts with a single line
2249 my @start_request; @start_request = (line => sub {
2250 my ($hdl, $line) = @_;
2251
2252 ... handle request
2253
2254 # push next request read, possibly from a nested callback
2255 $hdl->push_read (@start_request);
2256 });
2257
2258 # auth done, now go into request handling loop
2259 # now push the first @start_request
2260 $hdl->push_read (@start_request);
2261
2262By always having an outstanding C<push_read>, the handle always expects
2263some data and raises the C<EPIPE> error when the connction is dropped
2264unexpectedly.
2265
2266The second variant is a protocol where the client can drop the connection
2267at any time. For TCP, this means that the server machine may run out of
2268sockets easier, and in general, it means you cannot distinguish a protocl
2269failure/client crash from a normal connection close. Nevertheless, these
2270kinds of protocols are common (and sometimes even the best solution to the
2271problem).
2272
2273Having an outstanding read request at all times is possible if you ignore
2274C<EPIPE> errors, but this doesn't help with when the client drops the
2275connection during a request, which would still be an error.
2276
2277A better solution is to push the initial request read in an C<on_read>
2278callback. This avoids an error, as when the server doesn't expect data
2279(i.e. is idly waiting for the next request, an EOF will not raise an
2280error, but simply result in an C<on_eof> callback. It is also a bit slower
2281and simpler:
2282
2283 # auth done, now go into request handling loop
2284 $hdl->on_read (sub {
2285 my ($hdl) = @_;
2286
2287 # called each time we receive data but the read queue is empty
2288 # simply start read the request
2289
2290 $hdl->push_read (line => sub {
2291 my ($hdl, $line) = @_;
2292
2293 ... handle request
2294
2295 # do nothing special when the request has been handled, just
2296 # let the request queue go empty.
2297 });
2298 });
2299
2057=item I get different callback invocations in TLS mode/Why can't I pause 2300=item I get different callback invocations in TLS mode/Why can't I pause
2058reading? 2301reading?
2059 2302
2060Unlike, say, TCP, TLS connections do not consist of two independent 2303Unlike, say, TCP, TLS connections do not consist of two independent
2061communication channels, one for each direction. Or put differently. The 2304communication channels, one for each direction. Or put differently, the
2062read and write directions are not independent of each other: you cannot 2305read and write directions are not independent of each other: you cannot
2063write data unless you are also prepared to read, and vice versa. 2306write data unless you are also prepared to read, and vice versa.
2064 2307
2065This can mean than, in TLS mode, you might get C<on_error> or C<on_eof> 2308This means that, in TLS mode, you might get C<on_error> or C<on_eof>
2066callback invocations when you are not expecting any read data - the reason 2309callback invocations when you are not expecting any read data - the reason
2067is that AnyEvent::Handle always reads in TLS mode. 2310is that AnyEvent::Handle always reads in TLS mode.
2068 2311
2069During the connection, you have to make sure that you always have a 2312During the connection, you have to make sure that you always have a
2070non-empty read-queue, or an C<on_read> watcher. At the end of the 2313non-empty read-queue, or an C<on_read> watcher. At the end of the
… …
2082 $handle->on_eof (undef); 2325 $handle->on_eof (undef);
2083 $handle->on_error (sub { 2326 $handle->on_error (sub {
2084 my $data = delete $_[0]{rbuf}; 2327 my $data = delete $_[0]{rbuf};
2085 }); 2328 });
2086 2329
2330Note that this example removes the C<rbuf> member from the handle object,
2331which is not normally allowed by the API. It is expressly permitted in
2332this case only, as the handle object needs to be destroyed afterwards.
2333
2087The reason to use C<on_error> is that TCP connections, due to latencies 2334The reason to use C<on_error> is that TCP connections, due to latencies
2088and packets loss, might get closed quite violently with an error, when in 2335and packets loss, might get closed quite violently with an error, when in
2089fact, all data has been received. 2336fact all data has been received.
2090 2337
2091It is usually better to use acknowledgements when transferring data, 2338It is usually better to use acknowledgements when transferring data,
2092to make sure the other side hasn't just died and you got the data 2339to make sure the other side hasn't just died and you got the data
2093intact. This is also one reason why so many internet protocols have an 2340intact. This is also one reason why so many internet protocols have an
2094explicit QUIT command. 2341explicit QUIT command.
… …
2101C<low_water_mark> this will be called precisely when all data has been 2348C<low_water_mark> this will be called precisely when all data has been
2102written to the socket: 2349written to the socket:
2103 2350
2104 $handle->push_write (...); 2351 $handle->push_write (...);
2105 $handle->on_drain (sub { 2352 $handle->on_drain (sub {
2106 warn "all data submitted to the kernel\n"; 2353 AE::log debug => "All data submitted to the kernel.";
2107 undef $handle; 2354 undef $handle;
2108 }); 2355 });
2109 2356
2110If you just want to queue some data and then signal EOF to the other side, 2357If you just want to queue some data and then signal EOF to the other side,
2111consider using C<< ->push_shutdown >> instead. 2358consider using C<< ->push_shutdown >> instead.
2112 2359
2113=item I want to contact a TLS/SSL server, I don't care about security. 2360=item I want to contact a TLS/SSL server, I don't care about security.
2114 2361
2115If your TLS server is a pure TLS server (e.g. HTTPS) that only speaks TLS, 2362If your TLS server is a pure TLS server (e.g. HTTPS) that only speaks TLS,
2116simply connect to it and then create the AnyEvent::Handle with the C<tls> 2363connect to it and then create the AnyEvent::Handle with the C<tls>
2117parameter: 2364parameter:
2118 2365
2119 tcp_connect $host, $port, sub { 2366 tcp_connect $host, $port, sub {
2120 my ($fh) = @_; 2367 my ($fh) = @_;
2121 2368
… …
2195When you have intermediate CA certificates that your clients might not 2442When you have intermediate CA certificates that your clients might not
2196know about, just append them to the C<cert_file>. 2443know about, just append them to the C<cert_file>.
2197 2444
2198=back 2445=back
2199 2446
2200
2201=head1 SUBCLASSING AnyEvent::Handle 2447=head1 SUBCLASSING AnyEvent::Handle
2202 2448
2203In many cases, you might want to subclass AnyEvent::Handle. 2449In many cases, you might want to subclass AnyEvent::Handle.
2204 2450
2205To make this easier, a given version of AnyEvent::Handle uses these 2451To make this easier, a given version of AnyEvent::Handle uses these
… …
2221 2467
2222=item * all members not documented here and not prefixed with an underscore 2468=item * all members not documented here and not prefixed with an underscore
2223are free to use in subclasses. 2469are free to use in subclasses.
2224 2470
2225Of course, new versions of AnyEvent::Handle may introduce more "public" 2471Of course, new versions of AnyEvent::Handle may introduce more "public"
2226member variables, but thats just life, at least it is documented. 2472member variables, but that's just life. At least it is documented.
2227 2473
2228=back 2474=back
2229 2475
2230=head1 AUTHOR 2476=head1 AUTHOR
2231 2477
2232Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>. 2478Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>.
2233 2479
2234=cut 2480=cut
2235 2481
22361; # End of AnyEvent::Handle 24821
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