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Revision 1.182 by root, Thu Sep 3 12:35:01 2009 UTC vs.
Revision 1.231 by root, Tue Mar 27 23:47:57 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 => "Got 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
… …
60use AnyEvent (); BEGIN { AnyEvent::common_sense } 60use AnyEvent (); BEGIN { AnyEvent::common_sense }
61use AnyEvent::Util qw(WSAEWOULDBLOCK); 61use AnyEvent::Util qw(WSAEWOULDBLOCK);
62 62
63our $VERSION = $AnyEvent::VERSION; 63our $VERSION = $AnyEvent::VERSION;
64 64
65sub _load_func($) {
66 my $func = $_[0];
67
68 unless (defined &$func) {
69 my $pkg = $func;
70 do {
71 $pkg =~ s/::[^:]+$//
72 or return;
73 eval "require $pkg";
74 } until defined &$func;
75 }
76
77 \&$func
78}
79
80sub MAX_READ_SIZE() { 131072 }
81
65=head1 METHODS 82=head1 METHODS
66 83
67=over 4 84=over 4
68 85
69=item $handle = B<new> AnyEvent::TLS fh => $filehandle, key => value... 86=item $handle = B<new> AnyEvent::Handle fh => $filehandle, key => value...
70 87
71The constructor supports these arguments (all as C<< key => value >> pairs). 88The constructor supports these arguments (all as C<< key => value >> pairs).
72 89
73=over 4 90=over 4
74 91
… …
97=over 4 114=over 4
98 115
99=item on_prepare => $cb->($handle) 116=item on_prepare => $cb->($handle)
100 117
101This (rarely used) callback is called before a new connection is 118This (rarely used) callback is called before a new connection is
102attempted, 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
103prepare the file handle with parameters required for the actual connect 121file handle with parameters required for the actual connect (as opposed to
104(as opposed to settings that can be changed when the connection is already 122settings that can be changed when the connection is already established).
105established).
106 123
107The 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
108seconds (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
109timeout is to be used). 126default timeout is to be used).
110 127
111=item on_connect => $cb->($handle, $host, $port, $retry->()) 128=item on_connect => $cb->($handle, $host, $port, $retry->())
112 129
113This callback is called when a connection has been successfully established. 130This callback is called when a connection has been successfully established.
114 131
115The actual numeric host and port (the socket peername) are passed as 132The peer's numeric host and port (the socket peername) are passed as
116parameters, together with a retry callback. 133parameters, together with a retry callback. At the time it is called the
134read and write queues, EOF status, TLS status and similar properties of
135the handle will have been reset.
117 136
137It is not allowed to use the read or write queues while the handle object
138is connecting.
139
118When, for some reason, the handle is not acceptable, then calling 140If, for some reason, the handle is not acceptable, calling C<$retry> will
119C<$retry> will continue with the next conenction target (in case of 141continue with the next connection target (in case of multi-homed hosts or
120multi-homed hosts or SRV records there can be multiple connection 142SRV records there can be multiple connection endpoints). The C<$retry>
121endpoints). 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
122tls 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.
123 146
124In most cases, ignoring the C<$retry> parameter is the way to go. 147In most cases, you should ignore the C<$retry> parameter.
125 148
126=item on_connect_error => $cb->($handle, $message) 149=item on_connect_error => $cb->($handle, $message)
127 150
128This callback is called when the conenction could not be 151This callback is called when the connection could not be
129established. C<$!> will contain the relevant error code, and C<$message> a 152established. C<$!> will contain the relevant error code, and C<$message> a
130message describing it (usually the same as C<"$!">). 153message describing it (usually the same as C<"$!">).
131 154
132If 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
133fatal error instead. 156fatal error instead.
… …
136 159
137=item on_error => $cb->($handle, $fatal, $message) 160=item on_error => $cb->($handle, $fatal, $message)
138 161
139This is the error callback, which is called when, well, some error 162This is the error callback, which is called when, well, some error
140occured, such as not being able to resolve the hostname, failure to 163occured, such as not being able to resolve the hostname, failure to
141connect or a read error. 164connect, or a read error.
142 165
143Some errors are fatal (which is indicated by C<$fatal> being true). On 166Some errors are fatal (which is indicated by C<$fatal> being true). On
144fatal errors the handle object will be destroyed (by a call to C<< -> 167fatal errors the handle object will be destroyed (by a call to C<< ->
145destroy >>) after invoking the error callback (which means you are free to 168destroy >>) after invoking the error callback (which means you are free to
146examine the handle object). Examples of fatal errors are an EOF condition 169examine the handle object). Examples of fatal errors are an EOF condition
147with active (but unsatisifable) read watchers (C<EPIPE>) or I/O errors. In 170with active (but unsatisfiable) read watchers (C<EPIPE>) or I/O errors. In
148cases where the other side can close the connection at their will it is 171cases where the other side can close the connection at will, it is
149often easiest to not report C<EPIPE> errors in this callback. 172often easiest to not report C<EPIPE> errors in this callback.
150 173
151AnyEvent::Handle tries to find an appropriate error code for you to check 174AnyEvent::Handle tries to find an appropriate error code for you to check
152against, but in some cases (TLS errors), this does not work well. It is 175against, but in some cases (TLS errors), this does not work well. It is
153recommended to always output the C<$message> argument in human-readable 176recommended to always output the C<$message> argument in human-readable
154error messages (it's usually the same as C<"$!">). 177error messages (it's usually the same as C<"$!">).
155 178
156Non-fatal errors can be retried by simply returning, but it is recommended 179Non-fatal errors can be retried by returning, but it is recommended
157to simply ignore this parameter and instead abondon the handle object 180to simply ignore this parameter and instead abondon the handle object
158when this callback is invoked. Examples of non-fatal errors are timeouts 181when this callback is invoked. Examples of non-fatal errors are timeouts
159C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>). 182C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>).
160 183
161On callback entrance, the value of C<$!> contains the operating system 184On entry to the callback, the value of C<$!> contains the operating
162error code (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT>, C<EBADMSG> or 185system error code (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT>, C<EBADMSG> or
163C<EPROTO>). 186C<EPROTO>).
164 187
165While 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
166you will not be notified of errors otherwise. The default simply calls 189you will not be notified of errors otherwise. The default just calls
167C<croak>. 190C<croak>.
168 191
169=item on_read => $cb->($handle) 192=item on_read => $cb->($handle)
170 193
171This sets the default read callback, which is called when data arrives 194This sets the default read callback, which is called when data arrives
… …
176To access (and remove data from) the read buffer, use the C<< ->rbuf >> 199To access (and remove data from) the read buffer, use the C<< ->rbuf >>
177method or access the C<< $handle->{rbuf} >> member directly. Note that you 200method or access the C<< $handle->{rbuf} >> member directly. Note that you
178must not enlarge or modify the read buffer, you can only remove data at 201must not enlarge or modify the read buffer, you can only remove data at
179the beginning from it. 202the beginning from it.
180 203
204You can also call C<< ->push_read (...) >> or any other function that
205modifies the read queue. Or do both. Or ...
206
181When an EOF condition is detected then AnyEvent::Handle will first try to 207When an EOF condition is detected, AnyEvent::Handle will first try to
182feed all the remaining data to the queued callbacks and C<on_read> before 208feed all the remaining data to the queued callbacks and C<on_read> before
183calling the C<on_eof> callback. If no progress can be made, then a fatal 209calling the C<on_eof> callback. If no progress can be made, then a fatal
184error will be raised (with C<$!> set to C<EPIPE>). 210error will be raised (with C<$!> set to C<EPIPE>).
185 211
186Note that, unlike requests in the read queue, an C<on_read> callback 212Note that, unlike requests in the read queue, an C<on_read> callback
… …
204If an EOF condition has been detected but no C<on_eof> callback has been 230If an EOF condition has been detected but no C<on_eof> callback has been
205set, then a fatal error will be raised with C<$!> set to <0>. 231set, then a fatal error will be raised with C<$!> set to <0>.
206 232
207=item on_drain => $cb->($handle) 233=item on_drain => $cb->($handle)
208 234
209This 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
210(or when the callback is set and the buffer is empty already). 236empty (and immediately when the handle object is created).
211 237
212To append to the write buffer, use the C<< ->push_write >> method. 238To append to the write buffer, use the C<< ->push_write >> method.
213 239
214This 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
215into 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
… …
227many seconds pass without a successful read or write on the underlying 253many seconds pass without a successful read or write on the underlying
228file 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
229will 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>
230error will be raised). 256error will be raised).
231 257
232There are three variants of the timeouts that work fully independent 258There are three variants of the timeouts that work independently of each
233of 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:
234C<timeout>, C<rtimeout> and C<wtimeout>, with corresponding callbacks 261C<timeout>, C<rtimeout> and C<wtimeout>, with corresponding callbacks
235C<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
236C<timeout_reset>, C<rtimeout_reset>, and C<wtimeout_reset>. 263C<timeout_reset>, C<rtimeout_reset>, and C<wtimeout_reset>.
237 264
238Note 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
239any outstanding read or write requests: If you plan to keep the connection 266outstanding read or write requests: If you plan to keep the connection
240idle then you should disable the timout temporarily or ignore the timeout 267idle then you should disable the timeout temporarily or ignore the
241in the C<on_timeout> callback, in which case AnyEvent::Handle will simply 268timeout in the corresponding C<on_timeout> callback, in which case
242restart the timeout. 269AnyEvent::Handle will simply restart the timeout.
243 270
244Zero (the default) disables this timeout. 271Zero (the default) disables the corresponding timeout.
245 272
246=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)
247 278
248Called whenever the inactivity timeout passes. If you return from this 279Called whenever the inactivity timeout passes. If you return from this
249callback, 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,
250so this condition is not fatal in any way. 281so this condition is not fatal in any way.
251 282
… …
259be 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
260(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
261amount 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
262isn't finished). 293isn't finished).
263 294
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
264=item autocork => <boolean> 310=item autocork => <boolean>
265 311
266When disabled (the default), then C<push_write> will try to immediately 312When disabled (the default), C<push_write> will try to immediately
267write 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
268a 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
269be inefficient if you write multiple small chunks (on the wire, this 315be inefficient if you write multiple small chunks (on the wire, this
270disadvantage is usually avoided by your kernel's nagle algorithm, see 316disadvantage is usually avoided by your kernel's nagle algorithm, see
271C<no_delay>, but this option can save costly syscalls). 317C<no_delay>, but this option can save costly syscalls).
272 318
273When enabled, then writes will always be queued till the next event loop 319When enabled, writes will always be queued till the next event loop
274iteration. This is efficient when you do many small writes per iteration, 320iteration. This is efficient when you do many small writes per iteration,
275but 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
276the write buffer often is full). It also increases write latency. 322the write buffer often is full). It also increases write latency.
277 323
278=item no_delay => <boolean> 324=item no_delay => <boolean>
… …
282the Nagle algorithm, and usually it is beneficial. 328the Nagle algorithm, and usually it is beneficial.
283 329
284In 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
285accomplishd by setting this option to a true value. 331accomplishd by setting this option to a true value.
286 332
287The default is your opertaing system's default behaviour (most likely 333The default is your operating system's default behaviour (most likely
288enabled), this option explicitly enables or disables it, if possible. 334enabled). This option explicitly enables or disables it, if possible.
289 335
290=item keepalive => <boolean> 336=item keepalive => <boolean>
291 337
292Enables (default disable) the SO_KEEPALIVE option on the stream socket: 338Enables (default disable) the SO_KEEPALIVE option on the stream socket:
293normally, TCP connections have no time-out once established, so TCP 339normally, TCP connections have no time-out once established, so TCP
294conenctions, once established, can stay alive forever even when the other 340connections, once established, can stay alive forever even when the other
295side 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
296TCP connections whent he other side becomes unreachable. While the default 342TCP connections when the other side becomes unreachable. While the default
297is OS-dependent, TCP keepalives usually kick in after around two hours, 343is OS-dependent, TCP keepalives usually kick in after around two hours,
298and, 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
299to 15 minutes later. 345to 15 minutes later.
300 346
301It 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
… …
306 352
307BSD majorly fucked up the implementation of TCP urgent data. The result 353BSD majorly fucked up the implementation of TCP urgent data. The result
308is that almost no OS implements TCP according to the specs, and every OS 354is that almost no OS implements TCP according to the specs, and every OS
309implements it slightly differently. 355implements it slightly differently.
310 356
311If you want to handle TCP urgent data, then setting this flag gives you 357If you want to handle TCP urgent data, then setting this flag (the default
312the most portable way of getting urgent data, by putting it into the 358is enabled) gives you the most portable way of getting urgent data, by
313stream. 359putting it into the stream.
360
361Since BSD emulation of OOB data on top of TCP's urgent data can have
362security implications, AnyEvent::Handle sets this flag automatically
363unless explicitly specified. Note that setting this flag after
364establishing a connection I<may> be a bit too late (data loss could
365already have occured on BSD systems), but at least it will protect you
366from most attacks.
314 367
315=item read_size => <bytes> 368=item read_size => <bytes>
316 369
317The default read block size (the amount of bytes this module will 370The initial read block size, the number of bytes this module will try
318try to read during each loop iteration, which affects memory 371to read during each loop iteration. Each handle object will consume
319requirements). 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.
320 382
321=item low_water_mark => <bytes> 383=item low_water_mark => <bytes>
322 384
323Sets 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
324buffer: 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
325considered empty. 387considered empty.
326 388
327Sometimes it can be beneficial (for performance reasons) to add data to 389Sometimes it can be beneficial (for performance reasons) to add data to
328the 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
329the operating system kernel usually buffers data as well, so the default 391the operating system kernel usually buffers data as well, so the default
330is good in almost all cases. 392is good in almost all cases.
331 393
332=item linger => <seconds> 394=item linger => <seconds>
333 395
334If non-zero (default: C<3600>), then the destructor of the 396If this is non-zero (default: C<3600>), the destructor of the
335AnyEvent::Handle object will check whether there is still outstanding 397AnyEvent::Handle object will check whether there is still outstanding
336write 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
337socket. No errors will be reported (this mostly matches how the operating 399socket. No errors will be reported (this mostly matches how the operating
338system treats outstanding data at socket close time). 400system treats outstanding data at socket close time).
339 401
… …
346A string used to identify the remote site - usually the DNS hostname 408A string used to identify the remote site - usually the DNS hostname
347(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.
348 410
349Apart 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
350peername verification (see C<verify_peername> in L<AnyEvent::TLS>). This 412peername verification (see C<verify_peername> in L<AnyEvent::TLS>). This
351verification will be skipped when C<peername> is not specified or 413verification will be skipped when C<peername> is not specified or is
352C<undef>. 414C<undef>.
353 415
354=item tls => "accept" | "connect" | Net::SSLeay::SSL object 416=item tls => "accept" | "connect" | Net::SSLeay::SSL object
355 417
356When this parameter is given, it enables TLS (SSL) mode, that means 418When this parameter is given, it enables TLS (SSL) mode, that means
357AnyEvent will start a TLS handshake as soon as the conenction has been 419AnyEvent will start a TLS handshake as soon as the connection has been
358established and will transparently encrypt/decrypt data afterwards. 420established and will transparently encrypt/decrypt data afterwards.
359 421
360All TLS protocol errors will be signalled as C<EPROTO>, with an 422All TLS protocol errors will be signalled as C<EPROTO>, with an
361appropriate error message. 423appropriate error message.
362 424
… …
382B<IMPORTANT:> since Net::SSLeay "objects" are really only integers, 444B<IMPORTANT:> since Net::SSLeay "objects" are really only integers,
383passing 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
384happens 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
385segmentation fault. 447segmentation fault.
386 448
387See 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.
388 450
389=item tls_ctx => $anyevent_tls 451=item tls_ctx => $anyevent_tls
390 452
391Use 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
392(unless a connection object was specified directly). If this parameter is 454(unless a connection object was specified directly). If this
393missing, 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>.
394 457
395Instead 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
396=> 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
397new TLS context object. 460new TLS context object.
398 461
… …
407 470
408TLS 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
409callback 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>.
410 473
411Without this callback, handshake failures lead to C<on_error> being 474Without this callback, handshake failures lead to C<on_error> being
412called, as normal. 475called as usual.
413 476
414Note 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
415need 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
416then call C<< ->starttls >> again. 479then call C<< ->starttls >> again.
417 480
418=item on_stoptls => $cb->($handle) 481=item on_stoptls => $cb->($handle)
419 482
… …
467 $self->{connect}[0], 530 $self->{connect}[0],
468 $self->{connect}[1], 531 $self->{connect}[1],
469 sub { 532 sub {
470 my ($fh, $host, $port, $retry) = @_; 533 my ($fh, $host, $port, $retry) = @_;
471 534
535 delete $self->{_connect}; # no longer needed
536
472 if ($fh) { 537 if ($fh) {
473 $self->{fh} = $fh; 538 $self->{fh} = $fh;
474 539
475 delete $self->{_skip_drain_rbuf}; 540 delete $self->{_skip_drain_rbuf};
476 $self->_start; 541 $self->_start;
… …
483 }); 548 });
484 549
485 } else { 550 } else {
486 if ($self->{on_connect_error}) { 551 if ($self->{on_connect_error}) {
487 $self->{on_connect_error}($self, "$!"); 552 $self->{on_connect_error}($self, "$!");
488 $self->destroy; 553 $self->destroy if $self;
489 } else { 554 } else {
490 $self->_error ($!, 1); 555 $self->_error ($!, 1);
491 } 556 }
492 } 557 }
493 }, 558 },
494 sub { 559 sub {
495 local $self->{fh} = $_[0]; 560 local $self->{fh} = $_[0];
496 561
497 $self->{on_prepare} 562 $self->{on_prepare}
498 ? $self->{on_prepare}->($self) 563 ? $self->{on_prepare}->($self)
499 : () 564 : ()
500 } 565 }
501 ); 566 );
502 } 567 }
503 568
… …
509} 574}
510 575
511sub _start { 576sub _start {
512 my ($self) = @_; 577 my ($self) = @_;
513 578
579 # too many clueless people try to use udp and similar sockets
580 # with AnyEvent::Handle, do them a favour.
581 my $type = getsockopt $self->{fh}, Socket::SOL_SOCKET (), Socket::SO_TYPE ();
582 Carp::croak "AnyEvent::Handle: only stream sockets supported, anything else will NOT work!"
583 if Socket::SOCK_STREAM () != (unpack "I", $type) && defined $type;
584
514 AnyEvent::Util::fh_nonblocking $self->{fh}, 1; 585 AnyEvent::Util::fh_nonblocking $self->{fh}, 1;
515 586
516 $self->{_activity} = 587 $self->{_activity} =
517 $self->{_ractivity} = 588 $self->{_ractivity} =
518 $self->{_wactivity} = AE::now; 589 $self->{_wactivity} = AE::now;
519 590
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
520 $self->timeout (delete $self->{timeout} ) if $self->{timeout}; 595 $self->timeout (delete $self->{timeout} ) if $self->{timeout};
521 $self->rtimeout (delete $self->{rtimeout} ) if $self->{rtimeout}; 596 $self->rtimeout (delete $self->{rtimeout} ) if $self->{rtimeout};
522 $self->wtimeout (delete $self->{wtimeout} ) if $self->{wtimeout}; 597 $self->wtimeout (delete $self->{wtimeout} ) if $self->{wtimeout};
523 598
524 $self->no_delay (delete $self->{no_delay} ) if exists $self->{no_delay}; 599 $self->no_delay (delete $self->{no_delay} ) if exists $self->{no_delay} && $self->{no_delay};
525 $self->keepalive (delete $self->{keepalive}) if exists $self->{keepalive}; 600 $self->keepalive (delete $self->{keepalive}) if exists $self->{keepalive} && $self->{keepalive};
601
526 $self->oobinline (delete $self->{oobinline}) if exists $self->{oobinline}; 602 $self->oobinline (exists $self->{oobinline} ? delete $self->{oobinline} : 1);
527 603
528 $self->starttls (delete $self->{tls}, delete $self->{tls_ctx}) 604 $self->starttls (delete $self->{tls}, delete $self->{tls_ctx})
529 if $self->{tls}; 605 if $self->{tls};
530 606
531 $self->on_drain (delete $self->{on_drain}) if $self->{on_drain}; 607 $self->on_drain (delete $self->{on_drain} ) if $self->{on_drain};
532 608
533 $self->start_read 609 $self->start_read
534 if $self->{on_read} || @{ $self->{_queue} }; 610 if $self->{on_read} || @{ $self->{_queue} };
535 611
536 $self->_drain_wbuf; 612 $self->_drain_wbuf;
… …
543 $message ||= "$!"; 619 $message ||= "$!";
544 620
545 if ($self->{on_error}) { 621 if ($self->{on_error}) {
546 $self->{on_error}($self, $fatal, $message); 622 $self->{on_error}($self, $fatal, $message);
547 $self->destroy if $fatal; 623 $self->destroy if $fatal;
548 } elsif ($self->{fh}) { 624 } elsif ($self->{fh} || $self->{connect}) {
549 $self->destroy; 625 $self->destroy;
550 Carp::croak "AnyEvent::Handle uncaught error: $message"; 626 Carp::croak "AnyEvent::Handle uncaught error: $message";
551 } 627 }
552} 628}
553 629
… …
612=cut 688=cut
613 689
614sub no_delay { 690sub no_delay {
615 $_[0]{no_delay} = $_[1]; 691 $_[0]{no_delay} = $_[1];
616 692
617 eval {
618 local $SIG{__DIE__};
619 setsockopt $_[0]{fh}, Socket::IPPROTO_TCP (), Socket::TCP_NODELAY (), int $_[1] 693 setsockopt $_[0]{fh}, Socket::IPPROTO_TCP (), Socket::TCP_NODELAY (), int $_[1]
620 if $_[0]{fh}; 694 if $_[0]{fh};
621 };
622} 695}
623 696
624=item $handle->keepalive ($boolean) 697=item $handle->keepalive ($boolean)
625 698
626Enables or disables the C<keepalive> setting (see constructor argument of 699Enables or disables the C<keepalive> setting (see constructor argument of
… …
686 759
687Replace the current C<on_stoptls> callback (see the C<on_stoptls> constructor argument). 760Replace the current C<on_stoptls> callback (see the C<on_stoptls> constructor argument).
688 761
689=cut 762=cut
690 763
691sub on_starttls { 764sub on_stoptls {
692 $_[0]{on_stoptls} = $_[1]; 765 $_[0]{on_stoptls} = $_[1];
693} 766}
694 767
695=item $handle->rbuf_max ($max_octets) 768=item $handle->rbuf_max ($max_octets)
696 769
697Configures the C<rbuf_max> setting (C<undef> disables it). 770Configures the C<rbuf_max> setting (C<undef> disables it).
771
772=item $handle->wbuf_max ($max_octets)
773
774Configures the C<wbuf_max> setting (C<undef> disables it).
698 775
699=cut 776=cut
700 777
701sub rbuf_max { 778sub rbuf_max {
702 $_[0]{rbuf_max} = $_[1]; 779 $_[0]{rbuf_max} = $_[1];
703} 780}
704 781
782sub wbuf_max {
783 $_[0]{wbuf_max} = $_[1];
784}
785
705############################################################################# 786#############################################################################
706 787
707=item $handle->timeout ($seconds) 788=item $handle->timeout ($seconds)
708 789
709=item $handle->rtimeout ($seconds) 790=item $handle->rtimeout ($seconds)
710 791
711=item $handle->wtimeout ($seconds) 792=item $handle->wtimeout ($seconds)
712 793
713Configures (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.
714 798
715=item $handle->timeout_reset 799=item $handle->timeout_reset
716 800
717=item $handle->rtimeout_reset 801=item $handle->rtimeout_reset
718 802
… …
735 $_[0]{$on_timeout} = $_[1]; 819 $_[0]{$on_timeout} = $_[1];
736 }; 820 };
737 821
738 *$timeout = sub { 822 *$timeout = sub {
739 my ($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";
740 827
741 $self->{$timeout} = $new_value; 828 $self->{$timeout} = $new_value;
742 delete $self->{$tw}; &$cb; 829 delete $self->{$tw}; &$cb;
743 }; 830 };
744 831
… …
799 886
800The 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
801AnyEvent::Handle will automatically try to get rid of it for you. 888AnyEvent::Handle will automatically try to get rid of it for you.
802 889
803When 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
804water mark, the C<on_drain> callback will be invoked. 891water mark, the C<on_drain> callback will be invoked once.
805 892
806=over 4 893=over 4
807 894
808=item $handle->on_drain ($cb) 895=item $handle->on_drain ($cb)
809 896
810Sets the C<on_drain> callback or clears it (see the description of 897Sets the C<on_drain> callback or clears it (see the description of
811C<on_drain> in the constructor). 898C<on_drain> in the constructor).
812 899
900This method may invoke callbacks (and therefore the handle might be
901destroyed after it returns).
902
813=cut 903=cut
814 904
815sub on_drain { 905sub on_drain {
816 my ($self, $cb) = @_; 906 my ($self, $cb) = @_;
817 907
… …
821 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});
822} 912}
823 913
824=item $handle->push_write ($data) 914=item $handle->push_write ($data)
825 915
826Queues 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
827want (only limited by the available memory), as C<AnyEvent::Handle> 917you want (only limited by the available memory and C<wbuf_max>), as
828buffers it independently of the kernel. 918C<AnyEvent::Handle> buffers it independently of the kernel.
919
920This method may invoke callbacks (and therefore the handle might be
921destroyed after it returns).
829 922
830=cut 923=cut
831 924
832sub _drain_wbuf { 925sub _drain_wbuf {
833 my ($self) = @_; 926 my ($self) = @_;
… …
858 $cb->() unless $self->{autocork}; 951 $cb->() unless $self->{autocork};
859 952
860 # if still data left in wbuf, we need to poll 953 # if still data left in wbuf, we need to poll
861 $self->{_ww} = AE::io $self->{fh}, 1, $cb 954 $self->{_ww} = AE::io $self->{fh}, 1, $cb
862 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 }
863 }; 963 };
864} 964}
865 965
866our %WH; 966our %WH;
867 967
968# deprecated
868sub register_write_type($$) { 969sub register_write_type($$) {
869 $WH{$_[0]} = $_[1]; 970 $WH{$_[0]} = $_[1];
870} 971}
871 972
872sub push_write { 973sub push_write {
873 my $self = shift; 974 my $self = shift;
874 975
875 if (@_ > 1) { 976 if (@_ > 1) {
876 my $type = shift; 977 my $type = shift;
877 978
979 @_ = ($WH{$type} ||= _load_func "$type\::anyevent_write_type"
878 @_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write") 980 or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::push_write")
879 ->($self, @_); 981 ->($self, @_);
880 } 982 }
881 983
984 # we downgrade here to avoid hard-to-track-down bugs,
985 # and diagnose the problem earlier and better.
986
882 if ($self->{tls}) { 987 if ($self->{tls}) {
883 $self->{_tls_wbuf} .= $_[0]; 988 utf8::downgrade $self->{_tls_wbuf} .= $_[0];
884 &_dotls ($self) if $self->{fh}; 989 &_dotls ($self) if $self->{fh};
885 } else { 990 } else {
886 $self->{wbuf} .= $_[0]; 991 utf8::downgrade $self->{wbuf} .= $_[0];
887 $self->_drain_wbuf if $self->{fh}; 992 $self->_drain_wbuf if $self->{fh};
888 } 993 }
889} 994}
890 995
891=item $handle->push_write (type => @args) 996=item $handle->push_write (type => @args)
892 997
893Instead of formatting your data yourself, you can also let this module do 998Instead of formatting your data yourself, you can also let this module
894the job by specifying a type and type-specific arguments. 999do the job by specifying a type and type-specific arguments. You
1000can also specify the (fully qualified) name of a package, in which
1001case AnyEvent tries to load the package and then expects to find the
1002C<anyevent_write_type> function inside (see "custom write types", below).
895 1003
896Predefined types are (if you have ideas for additional types, feel free to 1004Predefined types are (if you have ideas for additional types, feel free to
897drop by and tell us): 1005drop by and tell us):
898 1006
899=over 4 1007=over 4
… …
979=cut 1087=cut
980 1088
981register_write_type storable => sub { 1089register_write_type storable => sub {
982 my ($self, $ref) = @_; 1090 my ($self, $ref) = @_;
983 1091
984 require Storable; 1092 require Storable unless $Storable::VERSION;
985 1093
986 pack "w/a*", Storable::nfreeze ($ref) 1094 pack "w/a*", Storable::nfreeze ($ref)
987}; 1095};
988 1096
989=back 1097=back
… …
994before 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
995C<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
996C<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
997replaces the C<on_drain> callback with: 1105replaces the C<on_drain> callback with:
998 1106
999 sub { shutdown $_[0]{fh}, 1 } # for push_shutdown 1107 sub { shutdown $_[0]{fh}, 1 }
1000 1108
1001This simply shuts down the write side and signals an EOF condition to the 1109This simply shuts down the write side and signals an EOF condition to the
1002the peer. 1110the peer.
1003 1111
1004You can rely on the normal read queue and C<on_eof> handling 1112You can rely on the normal read queue and C<on_eof> handling
1005afterwards. This is the cleanest way to close a connection. 1113afterwards. This is the cleanest way to close a connection.
1006 1114
1115This method may invoke callbacks (and therefore the handle might be
1116destroyed after it returns).
1117
1007=cut 1118=cut
1008 1119
1009sub push_shutdown { 1120sub push_shutdown {
1010 my ($self) = @_; 1121 my ($self) = @_;
1011 1122
1012 delete $self->{low_water_mark}; 1123 delete $self->{low_water_mark};
1013 $self->on_drain (sub { shutdown $_[0]{fh}, 1 }); 1124 $self->on_drain (sub { shutdown $_[0]{fh}, 1 });
1014} 1125}
1015 1126
1016=item AnyEvent::Handle::register_write_type type => $coderef->($handle, @args) 1127=item custom write types - Package::anyevent_write_type $handle, @args
1017 1128
1018This function (not method) lets you add your own types to C<push_write>. 1129Instead of one of the predefined types, you can also specify the name of
1130a package. AnyEvent will try to load the package and then expects to find
1131a function named C<anyevent_write_type> inside. If it isn't found, it
1132progressively tries to load the parent package until it either finds the
1133function (good) or runs out of packages (bad).
1134
1019Whenever the given C<type> is used, C<push_write> will invoke the code 1135Whenever the given C<type> is used, C<push_write> will the function with
1020reference with the handle object and the remaining arguments. 1136the handle object and the remaining arguments.
1021 1137
1022The code reference is supposed to return a single octet string that will 1138The function is supposed to return a single octet string that will be
1023be appended to the write buffer. 1139appended to the write buffer, so you can mentally treat this function as a
1140"arguments to on-the-wire-format" converter.
1024 1141
1025Note that this is a function, and all types registered this way will be 1142Example: implement a custom write type C<join> that joins the remaining
1026global, so try to use unique names. 1143arguments using the first one.
1144
1145 $handle->push_write (My::Type => " ", 1,2,3);
1146
1147 # uses the following package, which can be defined in the "My::Type" or in
1148 # the "My" modules to be auto-loaded, or just about anywhere when the
1149 # My::Type::anyevent_write_type is defined before invoking it.
1150
1151 package My::Type;
1152
1153 sub anyevent_write_type {
1154 my ($handle, $delim, @args) = @_;
1155
1156 join $delim, @args
1157 }
1027 1158
1028=cut 1159=cut
1029 1160
1030############################################################################# 1161#############################################################################
1031 1162
… …
1040ways, the "simple" way, using only C<on_read> and the "complex" way, using 1171ways, the "simple" way, using only C<on_read> and the "complex" way, using
1041a queue. 1172a queue.
1042 1173
1043In the simple case, you just install an C<on_read> callback and whenever 1174In the simple case, you just install an C<on_read> callback and whenever
1044new data arrives, it will be called. You can then remove some data (if 1175new data arrives, it will be called. You can then remove some data (if
1045enough is there) from the read buffer (C<< $handle->rbuf >>). Or you cna 1176enough is there) from the read buffer (C<< $handle->rbuf >>). Or you can
1046leave the data there if you want to accumulate more (e.g. when only a 1177leave the data there if you want to accumulate more (e.g. when only a
1047partial message has been received so far). 1178partial message has been received so far), or change the read queue with
1179e.g. C<push_read>.
1048 1180
1049In the more complex case, you want to queue multiple callbacks. In this 1181In the more complex case, you want to queue multiple callbacks. In this
1050case, AnyEvent::Handle will call the first queued callback each time new 1182case, AnyEvent::Handle will call the first queued callback each time new
1051data arrives (also the first time it is queued) and removes it when it has 1183data arrives (also the first time it is queued) and remove it when it has
1052done its job (see C<push_read>, below). 1184done its job (see C<push_read>, below).
1053 1185
1054This way you can, for example, push three line-reads, followed by reading 1186This way you can, for example, push three line-reads, followed by reading
1055a chunk of data, and AnyEvent::Handle will execute them in order. 1187a chunk of data, and AnyEvent::Handle will execute them in order.
1056 1188
… …
1187 1319
1188This replaces the currently set C<on_read> callback, or clears it (when 1320This replaces the currently set C<on_read> callback, or clears it (when
1189the new callback is C<undef>). See the description of C<on_read> in the 1321the new callback is C<undef>). See the description of C<on_read> in the
1190constructor. 1322constructor.
1191 1323
1324This method may invoke callbacks (and therefore the handle might be
1325destroyed after it returns).
1326
1192=cut 1327=cut
1193 1328
1194sub on_read { 1329sub on_read {
1195 my ($self, $cb) = @_; 1330 my ($self, $cb) = @_;
1196 1331
… …
1198 $self->_drain_rbuf if $cb; 1333 $self->_drain_rbuf if $cb;
1199} 1334}
1200 1335
1201=item $handle->rbuf 1336=item $handle->rbuf
1202 1337
1203Returns 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).
1204 1341
1205You can access the read buffer directly as the C<< ->{rbuf} >> 1342The only operation allowed on the read buffer (apart from looking at it)
1206member, if you want. However, the only operation allowed on the 1343is removing data from its beginning. Otherwise modifying or appending to
1207read buffer (apart from looking at it) is removing data from its 1344it is not allowed and will lead to hard-to-track-down bugs.
1208beginning. Otherwise modifying or appending to it is not allowed and will
1209lead to hard-to-track-down bugs.
1210 1345
1211NOTE: 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>
1212C<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
1213automatically 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.
1214 1350
1215=cut 1351=cut
1216 1352
1217sub rbuf : lvalue { 1353sub rbuf : lvalue {
1218 $_[0]{rbuf} 1354 $_[0]{rbuf}
… …
1235 1371
1236If enough data was available, then the callback must remove all data it is 1372If enough data was available, then the callback must remove all data it is
1237interested in (which can be none at all) and return a true value. After returning 1373interested in (which can be none at all) and return a true value. After returning
1238true, it will be removed from the queue. 1374true, it will be removed from the queue.
1239 1375
1376These methods may invoke callbacks (and therefore the handle might be
1377destroyed after it returns).
1378
1240=cut 1379=cut
1241 1380
1242our %RH; 1381our %RH;
1243 1382
1244sub register_read_type($$) { 1383sub register_read_type($$) {
… …
1250 my $cb = pop; 1389 my $cb = pop;
1251 1390
1252 if (@_) { 1391 if (@_) {
1253 my $type = shift; 1392 my $type = shift;
1254 1393
1394 $cb = ($RH{$type} ||= _load_func "$type\::anyevent_read_type"
1255 $cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_read") 1395 or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::push_read")
1256 ->($self, $cb, @_); 1396 ->($self, $cb, @_);
1257 } 1397 }
1258 1398
1259 push @{ $self->{_queue} }, $cb; 1399 push @{ $self->{_queue} }, $cb;
1260 $self->_drain_rbuf; 1400 $self->_drain_rbuf;
… …
1265 my $cb = pop; 1405 my $cb = pop;
1266 1406
1267 if (@_) { 1407 if (@_) {
1268 my $type = shift; 1408 my $type = shift;
1269 1409
1410 $cb = ($RH{$type} ||= _load_func "$type\::anyevent_read_type"
1270 $cb = ($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")
1271 ->($self, $cb, @_); 1412 ->($self, $cb, @_);
1272 } 1413 }
1273 1414
1274 unshift @{ $self->{_queue} }, $cb; 1415 unshift @{ $self->{_queue} }, $cb;
1275 $self->_drain_rbuf; 1416 $self->_drain_rbuf;
… …
1279 1420
1280=item $handle->unshift_read (type => @args, $cb) 1421=item $handle->unshift_read (type => @args, $cb)
1281 1422
1282Instead of providing a callback that parses the data itself you can chose 1423Instead of providing a callback that parses the data itself you can chose
1283between a number of predefined parsing formats, for chunks of data, lines 1424between a number of predefined parsing formats, for chunks of data, lines
1284etc. 1425etc. You can also specify the (fully qualified) name of a package, in
1426which case AnyEvent tries to load the package and then expects to find the
1427C<anyevent_read_type> function inside (see "custom read types", below).
1285 1428
1286Predefined types are (if you have ideas for additional types, feel free to 1429Predefined types are (if you have ideas for additional types, feel free to
1287drop by and tell us): 1430drop by and tell us):
1288 1431
1289=over 4 1432=over 4
… …
1295data. 1438data.
1296 1439
1297Example: read 2 bytes. 1440Example: read 2 bytes.
1298 1441
1299 $handle->push_read (chunk => 2, sub { 1442 $handle->push_read (chunk => 2, sub {
1300 warn "yay ", unpack "H*", $_[1]; 1443 say "yay " . unpack "H*", $_[1];
1301 }); 1444 });
1302 1445
1303=cut 1446=cut
1304 1447
1305register_read_type chunk => sub { 1448register_read_type chunk => sub {
… …
1339 if (@_ < 3) { 1482 if (@_ < 3) {
1340 # 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
1341 sub { 1484 sub {
1342 $_[0]{rbuf} =~ s/^([^\015\012]*)(\015?\012)// or return; 1485 $_[0]{rbuf} =~ s/^([^\015\012]*)(\015?\012)// or return;
1343 1486
1344 $cb->($_[0], $1, $2); 1487 $cb->($_[0], "$1", "$2");
1345 1 1488 1
1346 } 1489 }
1347 } else { 1490 } else {
1348 $eol = quotemeta $eol unless ref $eol; 1491 $eol = quotemeta $eol unless ref $eol;
1349 $eol = qr|^(.*?)($eol)|s; 1492 $eol = qr|^(.*?)($eol)|s;
1350 1493
1351 sub { 1494 sub {
1352 $_[0]{rbuf} =~ s/$eol// or return; 1495 $_[0]{rbuf} =~ s/$eol// or return;
1353 1496
1354 $cb->($_[0], $1, $2); 1497 $cb->($_[0], "$1", "$2");
1355 1 1498 1
1356 } 1499 }
1357 } 1500 }
1358}; 1501};
1359 1502
… …
1381the receive buffer when neither C<$accept> nor C<$reject> match, 1524the receive buffer when neither C<$accept> nor C<$reject> match,
1382and everything preceding and including the match will be accepted 1525and everything preceding and including the match will be accepted
1383unconditionally. This is useful to skip large amounts of data that you 1526unconditionally. This is useful to skip large amounts of data that you
1384know cannot be matched, so that the C<$accept> or C<$reject> regex do not 1527know cannot be matched, so that the C<$accept> or C<$reject> regex do not
1385have to start matching from the beginning. This is purely an optimisation 1528have to start matching from the beginning. This is purely an optimisation
1386and 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.
1387 1530
1388Example: 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
1389expect 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
1390a 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
1391it 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
1392required for the accept regex. 1535required for the accept regex.
1393 1536
1394 $handle->push_read (regex => 1537 $handle->push_read (regex =>
… …
1407 1550
1408 sub { 1551 sub {
1409 # accept 1552 # accept
1410 if ($$rbuf =~ $accept) { 1553 if ($$rbuf =~ $accept) {
1411 $data .= substr $$rbuf, 0, $+[0], ""; 1554 $data .= substr $$rbuf, 0, $+[0], "";
1412 $cb->($self, $data); 1555 $cb->($_[0], $data);
1413 return 1; 1556 return 1;
1414 } 1557 }
1415 1558
1416 # reject 1559 # reject
1417 if ($reject && $$rbuf =~ $reject) { 1560 if ($reject && $$rbuf =~ $reject) {
1418 $self->_error (Errno::EBADMSG); 1561 $_[0]->_error (Errno::EBADMSG);
1419 } 1562 }
1420 1563
1421 # skip 1564 # skip
1422 if ($skip && $$rbuf =~ $skip) { 1565 if ($skip && $$rbuf =~ $skip) {
1423 $data .= substr $$rbuf, 0, $+[0], ""; 1566 $data .= substr $$rbuf, 0, $+[0], "";
… …
1439 my ($self, $cb) = @_; 1582 my ($self, $cb) = @_;
1440 1583
1441 sub { 1584 sub {
1442 unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) { 1585 unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
1443 if ($_[0]{rbuf} =~ /[^0-9]/) { 1586 if ($_[0]{rbuf} =~ /[^0-9]/) {
1444 $self->_error (Errno::EBADMSG); 1587 $_[0]->_error (Errno::EBADMSG);
1445 } 1588 }
1446 return; 1589 return;
1447 } 1590 }
1448 1591
1449 my $len = $1; 1592 my $len = $1;
1450 1593
1451 $self->unshift_read (chunk => $len, sub { 1594 $_[0]->unshift_read (chunk => $len, sub {
1452 my $string = $_[1]; 1595 my $string = $_[1];
1453 $_[0]->unshift_read (chunk => 1, sub { 1596 $_[0]->unshift_read (chunk => 1, sub {
1454 if ($_[1] eq ",") { 1597 if ($_[1] eq ",") {
1455 $cb->($_[0], $string); 1598 $cb->($_[0], $string);
1456 } else { 1599 } else {
1457 $self->_error (Errno::EBADMSG); 1600 $_[0]->_error (Errno::EBADMSG);
1458 } 1601 }
1459 }); 1602 });
1460 }); 1603 });
1461 1604
1462 1 1605 1
… …
1535 1678
1536 my $data; 1679 my $data;
1537 my $rbuf = \$self->{rbuf}; 1680 my $rbuf = \$self->{rbuf};
1538 1681
1539 sub { 1682 sub {
1540 my $ref = eval { $json->incr_parse ($self->{rbuf}) }; 1683 my $ref = eval { $json->incr_parse ($_[0]{rbuf}) };
1541 1684
1542 if ($ref) { 1685 if ($ref) {
1543 $self->{rbuf} = $json->incr_text; 1686 $_[0]{rbuf} = $json->incr_text;
1544 $json->incr_text = ""; 1687 $json->incr_text = "";
1545 $cb->($self, $ref); 1688 $cb->($_[0], $ref);
1546 1689
1547 1 1690 1
1548 } elsif ($@) { 1691 } elsif ($@) {
1549 # error case 1692 # error case
1550 $json->incr_skip; 1693 $json->incr_skip;
1551 1694
1552 $self->{rbuf} = $json->incr_text; 1695 $_[0]{rbuf} = $json->incr_text;
1553 $json->incr_text = ""; 1696 $json->incr_text = "";
1554 1697
1555 $self->_error (Errno::EBADMSG); 1698 $_[0]->_error (Errno::EBADMSG);
1556 1699
1557 () 1700 ()
1558 } else { 1701 } else {
1559 $self->{rbuf} = ""; 1702 $_[0]{rbuf} = "";
1560 1703
1561 () 1704 ()
1562 } 1705 }
1563 } 1706 }
1564}; 1707};
… …
1574=cut 1717=cut
1575 1718
1576register_read_type storable => sub { 1719register_read_type storable => sub {
1577 my ($self, $cb) = @_; 1720 my ($self, $cb) = @_;
1578 1721
1579 require Storable; 1722 require Storable unless $Storable::VERSION;
1580 1723
1581 sub { 1724 sub {
1582 # 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
1583 defined (my $len = eval { unpack "w", $_[0]{rbuf} }) 1726 defined (my $len = eval { unpack "w", $_[0]{rbuf} })
1584 or return; 1727 or return;
… …
1597 # read remaining chunk 1740 # read remaining chunk
1598 $_[0]->unshift_read (chunk => $len, sub { 1741 $_[0]->unshift_read (chunk => $len, sub {
1599 if (my $ref = eval { Storable::thaw ($_[1]) }) { 1742 if (my $ref = eval { Storable::thaw ($_[1]) }) {
1600 $cb->($_[0], $ref); 1743 $cb->($_[0], $ref);
1601 } else { 1744 } else {
1602 $self->_error (Errno::EBADMSG); 1745 $_[0]->_error (Errno::EBADMSG);
1603 } 1746 }
1604 }); 1747 });
1605 } 1748 }
1606 1749
1607 1 1750 1
1608 } 1751 }
1609}; 1752};
1610 1753
1611=back 1754=back
1612 1755
1613=item AnyEvent::Handle::register_read_type type => $coderef->($handle, $cb, @args) 1756=item custom read types - Package::anyevent_read_type $handle, $cb, @args
1614 1757
1615This function (not method) lets you add your own types to C<push_read>. 1758Instead of one of the predefined types, you can also specify the name
1759of a package. AnyEvent will try to load the package and then expects to
1760find a function named C<anyevent_read_type> inside. If it isn't found, it
1761progressively tries to load the parent package until it either finds the
1762function (good) or runs out of packages (bad).
1616 1763
1617Whenever the given C<type> is used, C<push_read> will invoke the code 1764Whenever this type is used, C<push_read> will invoke the function with the
1618reference with the handle object, the callback and the remaining 1765handle object, the original callback and the remaining arguments.
1619arguments.
1620 1766
1621The code reference is supposed to return a callback (usually a closure) 1767The function is supposed to return a callback (usually a closure) that
1622that works as a plain read callback (see C<< ->push_read ($cb) >>). 1768works as a plain read callback (see C<< ->push_read ($cb) >>), so you can
1769mentally treat the function as a "configurable read type to read callback"
1770converter.
1623 1771
1624It should invoke the passed callback when it is done reading (remember to 1772It should invoke the original callback when it is done reading (remember
1625pass C<$handle> as first argument as all other callbacks do that). 1773to pass C<$handle> as first argument as all other callbacks do that,
1774although there is no strict requirement on this).
1626 1775
1627Note that this is a function, and all types registered this way will be
1628global, so try to use unique names.
1629
1630For examples, see the source of this module (F<perldoc -m AnyEvent::Handle>, 1776For examples, see the source of this module (F<perldoc -m
1631search for C<register_read_type>)). 1777AnyEvent::Handle>, search for C<register_read_type>)).
1632 1778
1633=item $handle->stop_read 1779=item $handle->stop_read
1634 1780
1635=item $handle->start_read 1781=item $handle->start_read
1636 1782
… …
1642Note that AnyEvent::Handle will automatically C<start_read> for you when 1788Note that AnyEvent::Handle will automatically C<start_read> for you when
1643you change the C<on_read> callback or push/unshift a read callback, and it 1789you change the C<on_read> callback or push/unshift a read callback, and it
1644will automatically C<stop_read> for you when neither C<on_read> is set nor 1790will automatically C<stop_read> for you when neither C<on_read> is set nor
1645there are any read requests in the queue. 1791there are any read requests in the queue.
1646 1792
1647These methods will have no effect when in TLS mode (as TLS doesn't support 1793In older versions of this module (<= 5.3), these methods had no effect,
1648half-duplex connections). 1794as TLS does not support half-duplex connections. In current versions they
1795work as expected, as this behaviour is required to avoid certain resource
1796attacks, where the program would be forced to read (and buffer) arbitrary
1797amounts of data before being able to send some data. The drawback is that
1798some readings of the the SSL/TLS specifications basically require this
1799attack to be working, as SSL/TLS implementations might stall sending data
1800during a rehandshake.
1801
1802As a guideline, during the initial handshake, you should not stop reading,
1803and as a client, it might cause problems, depending on your application.
1649 1804
1650=cut 1805=cut
1651 1806
1652sub stop_read { 1807sub stop_read {
1653 my ($self) = @_; 1808 my ($self) = @_;
1654 1809
1655 delete $self->{_rw} unless $self->{tls}; 1810 delete $self->{_rw};
1656} 1811}
1657 1812
1658sub start_read { 1813sub start_read {
1659 my ($self) = @_; 1814 my ($self) = @_;
1660 1815
1661 unless ($self->{_rw} || $self->{_eof}) { 1816 unless ($self->{_rw} || $self->{_eof} || !$self->{fh}) {
1662 Scalar::Util::weaken $self; 1817 Scalar::Util::weaken $self;
1663 1818
1664 $self->{_rw} = AE::io $self->{fh}, 0, sub { 1819 $self->{_rw} = AE::io $self->{fh}, 0, sub {
1665 my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf}); 1820 my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf});
1666 my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf; 1821 my $len = sysread $self->{fh}, $$rbuf, $self->{read_size}, length $$rbuf;
1667 1822
1668 if ($len > 0) { 1823 if ($len > 0) {
1669 $self->{_activity} = $self->{_ractivity} = AE::now; 1824 $self->{_activity} = $self->{_ractivity} = AE::now;
1670 1825
1671 if ($self->{tls}) { 1826 if ($self->{tls}) {
1672 Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf); 1827 Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf);
1673 1828
1674 &_dotls ($self); 1829 &_dotls ($self);
1675 } else { 1830 } else {
1676 $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);
1677 } 1838 }
1678 1839
1679 } elsif (defined $len) { 1840 } elsif (defined $len) {
1680 delete $self->{_rw}; 1841 delete $self->{_rw};
1681 $self->{_eof} = 1; 1842 $self->{_eof} = 1;
… …
1759 && ($tmp != $ERROR_SYSCALL || $!); 1920 && ($tmp != $ERROR_SYSCALL || $!);
1760 1921
1761 while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) { 1922 while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) {
1762 $self->{wbuf} .= $tmp; 1923 $self->{wbuf} .= $tmp;
1763 $self->_drain_wbuf; 1924 $self->_drain_wbuf;
1925 $self->{tls} or return; # tls session might have gone away in callback
1764 } 1926 }
1765 1927
1766 $self->{_on_starttls} 1928 $self->{_on_starttls}
1767 and Net::SSLeay::state ($self->{tls}) == Net::SSLeay::ST_OK () 1929 and Net::SSLeay::state ($self->{tls}) == Net::SSLeay::ST_OK ()
1768 and (delete $self->{_on_starttls})->($self, 1, "TLS/SSL connection established"); 1930 and (delete $self->{_on_starttls})->($self, 1, "TLS/SSL connection established");
… …
1790context in C<< $handle->{tls_ctx} >> after this call and can be used or 1952context in C<< $handle->{tls_ctx} >> after this call and can be used or
1791changed to your liking. Note that the handshake might have already started 1953changed to your liking. Note that the handshake might have already started
1792when this function returns. 1954when this function returns.
1793 1955
1794Due to bugs in OpenSSL, it might or might not be possible to do multiple 1956Due to bugs in OpenSSL, it might or might not be possible to do multiple
1795handshakes on the same stream. Best do not attempt to use the stream after 1957handshakes on the same stream. It is best to not attempt to use the
1796stopping TLS. 1958stream after stopping TLS.
1959
1960This method may invoke callbacks (and therefore the handle might be
1961destroyed after it returns).
1797 1962
1798=cut 1963=cut
1799 1964
1800our %TLS_CACHE; #TODO not yet documented, should we? 1965our %TLS_CACHE; #TODO not yet documented, should we?
1801 1966
… …
1852 Net::SSLeay::CTX_set_mode ($tls, 1|2); 2017 Net::SSLeay::CTX_set_mode ($tls, 1|2);
1853 2018
1854 $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); 2019 $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1855 $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); 2020 $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1856 2021
1857 Net::SSLeay::BIO_write ($self->{_rbio}, delete $self->{rbuf}); 2022 Net::SSLeay::BIO_write ($self->{_rbio}, $self->{rbuf});
2023 $self->{rbuf} = "";
1858 2024
1859 Net::SSLeay::set_bio ($tls, $self->{_rbio}, $self->{_wbio}); 2025 Net::SSLeay::set_bio ($tls, $self->{_rbio}, $self->{_wbio});
1860 2026
1861 $self->{_on_starttls} = sub { $_[0]{on_starttls}(@_) } 2027 $self->{_on_starttls} = sub { $_[0]{on_starttls}(@_) }
1862 if $self->{on_starttls}; 2028 if $self->{on_starttls};
… …
1867 2033
1868=item $handle->stoptls 2034=item $handle->stoptls
1869 2035
1870Shuts down the SSL connection - this makes a proper EOF handshake by 2036Shuts down the SSL connection - this makes a proper EOF handshake by
1871sending a close notify to the other side, but since OpenSSL doesn't 2037sending a close notify to the other side, but since OpenSSL doesn't
1872support non-blocking shut downs, it is not guarenteed that you can re-use 2038support non-blocking shut downs, it is not guaranteed that you can re-use
1873the stream afterwards. 2039the stream afterwards.
2040
2041This method may invoke callbacks (and therefore the handle might be
2042destroyed after it returns).
1874 2043
1875=cut 2044=cut
1876 2045
1877sub stoptls { 2046sub stoptls {
1878 my ($self) = @_; 2047 my ($self) = @_;
1879 2048
1880 if ($self->{tls}) { 2049 if ($self->{tls} && $self->{fh}) {
1881 Net::SSLeay::shutdown ($self->{tls}); 2050 Net::SSLeay::shutdown ($self->{tls});
1882 2051
1883 &_dotls; 2052 &_dotls;
1884 2053
1885# # we don't give a shit. no, we do, but we can't. no...#d# 2054# # we don't give a shit. no, we do, but we can't. no...#d#
… …
1897 if $self->{tls} > 0; 2066 if $self->{tls} > 0;
1898 2067
1899 delete @$self{qw(_rbio _wbio _tls_wbuf _on_starttls)}; 2068 delete @$self{qw(_rbio _wbio _tls_wbuf _on_starttls)};
1900} 2069}
1901 2070
2071=item $handle->resettls
2072
2073This rarely-used method simply resets and TLS state on the handle, usually
2074causing data loss.
2075
2076One case where it may be useful is when you want to skip over the data in
2077the stream but you are not interested in interpreting it, so data loss is
2078no concern.
2079
2080=cut
2081
2082*resettls = \&_freetls;
2083
1902sub DESTROY { 2084sub DESTROY {
1903 my ($self) = @_; 2085 my ($self) = @_;
1904 2086
1905 &_freetls; 2087 &_freetls;
1906 2088
… …
1915 push @linger, AE::io $fh, 1, sub { 2097 push @linger, AE::io $fh, 1, sub {
1916 my $len = syswrite $fh, $wbuf, length $wbuf; 2098 my $len = syswrite $fh, $wbuf, length $wbuf;
1917 2099
1918 if ($len > 0) { 2100 if ($len > 0) {
1919 substr $wbuf, 0, $len, ""; 2101 substr $wbuf, 0, $len, "";
1920 } else { 2102 } elsif (defined $len || ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK)) {
1921 @linger = (); # end 2103 @linger = (); # end
1922 } 2104 }
1923 }; 2105 };
1924 push @linger, AE::timer $linger, 0, sub { 2106 push @linger, AE::timer $linger, 0, sub {
1925 @linger = (); 2107 @linger = ();
… …
1962 2144
1963sub AnyEvent::Handle::destroyed::AUTOLOAD { 2145sub AnyEvent::Handle::destroyed::AUTOLOAD {
1964 #nop 2146 #nop
1965} 2147}
1966 2148
2149=item $handle->destroyed
2150
2151Returns false as long as the handle hasn't been destroyed by a call to C<<
2152->destroy >>, true otherwise.
2153
2154Can be useful to decide whether the handle is still valid after some
2155callback possibly destroyed the handle. For example, C<< ->push_write >>,
2156C<< ->starttls >> and other methods can call user callbacks, which in turn
2157can destroy the handle, so work can be avoided by checking sometimes:
2158
2159 $hdl->starttls ("accept");
2160 return if $hdl->destroyed;
2161 $hdl->push_write (...
2162
2163Note that the call to C<push_write> will silently be ignored if the handle
2164has been destroyed, so often you can just ignore the possibility of the
2165handle being destroyed.
2166
2167=cut
2168
2169sub destroyed { 0 }
2170sub AnyEvent::Handle::destroyed::destroyed { 1 }
2171
1967=item AnyEvent::Handle::TLS_CTX 2172=item AnyEvent::Handle::TLS_CTX
1968 2173
1969This function creates and returns the AnyEvent::TLS object used by default 2174This function creates and returns the AnyEvent::TLS object used by default
1970for TLS mode. 2175for TLS mode.
1971 2176
… …
1998 2203
1999It 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,
2000from within all other callbacks, you need to explicitly call the C<< 2205from within all other callbacks, you need to explicitly call the C<<
2001->destroy >> method. 2206->destroy >> method.
2002 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
2003=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
2004reading? 2289reading?
2005 2290
2006Unlike, say, TCP, TLS connections do not consist of two independent 2291Unlike, say, TCP, TLS connections do not consist of two independent
2007communication channels, one for each direction. Or put differently. The 2292communication channels, one for each direction. Or put differently, the
2008read and write directions are not independent of each other: you cannot 2293read and write directions are not independent of each other: you cannot
2009write data unless you are also prepared to read, and vice versa. 2294write data unless you are also prepared to read, and vice versa.
2010 2295
2011This 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>
2012callback invocations when you are not expecting any read data - the reason 2297callback invocations when you are not expecting any read data - the reason
2013is that AnyEvent::Handle always reads in TLS mode. 2298is that AnyEvent::Handle always reads in TLS mode.
2014 2299
2015During 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
2016non-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
… …
2028 $handle->on_eof (undef); 2313 $handle->on_eof (undef);
2029 $handle->on_error (sub { 2314 $handle->on_error (sub {
2030 my $data = delete $_[0]{rbuf}; 2315 my $data = delete $_[0]{rbuf};
2031 }); 2316 });
2032 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
2033The 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
2034and 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
2035fact, all data has been received. 2324fact all data has been received.
2036 2325
2037It is usually better to use acknowledgements when transferring data, 2326It is usually better to use acknowledgements when transferring data,
2038to 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
2039intact. 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
2040explicit QUIT command. 2329explicit QUIT command.
… …
2047C<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
2048written to the socket: 2337written to the socket:
2049 2338
2050 $handle->push_write (...); 2339 $handle->push_write (...);
2051 $handle->on_drain (sub { 2340 $handle->on_drain (sub {
2052 warn "all data submitted to the kernel\n"; 2341 AE::log debug => "All data submitted to the kernel.";
2053 undef $handle; 2342 undef $handle;
2054 }); 2343 });
2055 2344
2056If 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,
2057consider using C<< ->push_shutdown >> instead. 2346consider using C<< ->push_shutdown >> instead.
2058 2347
2059=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.
2060 2349
2061If 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,
2062simply 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>
2063parameter: 2352parameter:
2064 2353
2065 tcp_connect $host, $port, sub { 2354 tcp_connect $host, $port, sub {
2066 my ($fh) = @_; 2355 my ($fh) = @_;
2067 2356
… …
2141When you have intermediate CA certificates that your clients might not 2430When you have intermediate CA certificates that your clients might not
2142know about, just append them to the C<cert_file>. 2431know about, just append them to the C<cert_file>.
2143 2432
2144=back 2433=back
2145 2434
2146
2147=head1 SUBCLASSING AnyEvent::Handle 2435=head1 SUBCLASSING AnyEvent::Handle
2148 2436
2149In many cases, you might want to subclass AnyEvent::Handle. 2437In many cases, you might want to subclass AnyEvent::Handle.
2150 2438
2151To make this easier, a given version of AnyEvent::Handle uses these 2439To make this easier, a given version of AnyEvent::Handle uses these
… …
2167 2455
2168=item * all members not documented here and not prefixed with an underscore 2456=item * all members not documented here and not prefixed with an underscore
2169are free to use in subclasses. 2457are free to use in subclasses.
2170 2458
2171Of course, new versions of AnyEvent::Handle may introduce more "public" 2459Of course, new versions of AnyEvent::Handle may introduce more "public"
2172member variables, but thats just life, at least it is documented. 2460member variables, but that's just life. At least it is documented.
2173 2461
2174=back 2462=back
2175 2463
2176=head1 AUTHOR 2464=head1 AUTHOR
2177 2465
2178Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>. 2466Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>.
2179 2467
2180=cut 2468=cut
2181 2469
21821; # End of AnyEvent::Handle 24701
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