ViewVC Help
View File | Revision Log | Show Annotations | Download File
/cvs/AnyEvent/lib/AnyEvent/Handle.pm
(Generate patch)

Comparing AnyEvent/lib/AnyEvent/Handle.pm (file contents):
Revision 1.186 by root, Mon Sep 7 19:54:57 2009 UTC vs.
Revision 1.237 by root, Tue Jul 30 23:14:32 2013 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<$retry> will continue with the next connection target (in case of 141continue with the next connection target (in case of multi-homed hosts or
135multi-homed hosts or SRV records there can be multiple connection 142SRV records there can be multiple connection endpoints). The C<$retry>
136endpoints). At the time it is called the read and write queues, eof 143callback can be invoked after the connect callback returns, i.e. one can
137status, tls status and similar properties of the handle will have been 144start a handshake and then decide to retry with the next host if the
138reset. 145handshake fails.
139 146
140In most cases, ignoring the C<$retry> parameter is the way to go. 147In most cases, you should ignore the C<$retry> parameter.
141 148
142=item on_connect_error => $cb->($handle, $message) 149=item on_connect_error => $cb->($handle, $message)
143 150
144This callback is called when the connection could not be 151This callback is called when the connection could not be
145established. C<$!> will contain the relevant error code, and C<$message> a 152established. C<$!> will contain the relevant error code, and C<$message> a
… …
152 159
153=item on_error => $cb->($handle, $fatal, $message) 160=item on_error => $cb->($handle, $fatal, $message)
154 161
155This is the error callback, which is called when, well, some error 162This is the error callback, which is called when, well, some error
156occured, such as not being able to resolve the hostname, failure to 163occured, such as not being able to resolve the hostname, failure to
157connect or a read error. 164connect, or a read error.
158 165
159Some errors are fatal (which is indicated by C<$fatal> being true). On 166Some errors are fatal (which is indicated by C<$fatal> being true). On
160fatal errors the handle object will be destroyed (by a call to C<< -> 167fatal errors the handle object will be destroyed (by a call to C<< ->
161destroy >>) after invoking the error callback (which means you are free to 168destroy >>) after invoking the error callback (which means you are free to
162examine the handle object). Examples of fatal errors are an EOF condition 169examine the handle object). Examples of fatal errors are an EOF condition
163with active (but unsatisifable) read watchers (C<EPIPE>) or I/O errors. In 170with active (but unsatisfiable) read watchers (C<EPIPE>) or I/O errors. In
164cases where the other side can close the connection at their will it is 171cases where the other side can close the connection at will, it is
165often easiest to not report C<EPIPE> errors in this callback. 172often easiest to not report C<EPIPE> errors in this callback.
166 173
167AnyEvent::Handle tries to find an appropriate error code for you to check 174AnyEvent::Handle tries to find an appropriate error code for you to check
168against, but in some cases (TLS errors), this does not work well. It is 175against, but in some cases (TLS errors), this does not work well.
169recommended to always output the C<$message> argument in human-readable
170error messages (it's usually the same as C<"$!">).
171 176
177If you report the error to the user, it is recommended to always output
178the C<$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
172Non-fatal errors can be retried by simply returning, but it is recommended 185Non-fatal errors can be retried by returning, but it is recommended
173to simply ignore this parameter and instead abondon the handle object 186to simply ignore this parameter and instead abondon the handle object
174when this callback is invoked. Examples of non-fatal errors are timeouts 187when this callback is invoked. Examples of non-fatal errors are timeouts
175C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>). 188C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>).
176 189
177On callback entrance, the value of C<$!> contains the operating system 190On entry to the callback, the value of C<$!> contains the operating
178error code (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT>, C<EBADMSG> or 191system error code (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT>, C<EBADMSG> or
179C<EPROTO>). 192C<EPROTO>).
180 193
181While 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
182you will not be notified of errors otherwise. The default simply calls 195you will not be notified of errors otherwise. The default just calls
183C<croak>. 196C<croak>.
184 197
185=item on_read => $cb->($handle) 198=item on_read => $cb->($handle)
186 199
187This sets the default read callback, which is called when data arrives 200This sets the default read callback, which is called when data arrives
… …
192To 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 >>
193method or access the C<< $handle->{rbuf} >> member directly. Note that you 206method or access the C<< $handle->{rbuf} >> member directly. Note that you
194must not enlarge or modify the read buffer, you can only remove data at 207must not enlarge or modify the read buffer, you can only remove data at
195the beginning from it. 208the beginning from it.
196 209
210You can also call C<< ->push_read (...) >> or any other function that
211modifies the read queue. Or do both. Or ...
212
197When an EOF condition is detected then AnyEvent::Handle will first try to 213When an EOF condition is detected, AnyEvent::Handle will first try to
198feed all the remaining data to the queued callbacks and C<on_read> before 214feed all the remaining data to the queued callbacks and C<on_read> before
199calling the C<on_eof> callback. If no progress can be made, then a fatal 215calling the C<on_eof> callback. If no progress can be made, then a fatal
200error will be raised (with C<$!> set to C<EPIPE>). 216error will be raised (with C<$!> set to C<EPIPE>).
201 217
202Note that, unlike requests in the read queue, an C<on_read> callback 218Note that, unlike requests in the read queue, an C<on_read> callback
… …
220If an EOF condition has been detected but no C<on_eof> callback has been 236If an EOF condition has been detected but no C<on_eof> callback has been
221set, then a fatal error will be raised with C<$!> set to <0>. 237set, then a fatal error will be raised with C<$!> set to <0>.
222 238
223=item on_drain => $cb->($handle) 239=item on_drain => $cb->($handle)
224 240
225This 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
226(or when the callback is set and the buffer is empty already). 242empty (and immediately when the handle object is created).
227 243
228To append to the write buffer, use the C<< ->push_write >> method. 244To append to the write buffer, use the C<< ->push_write >> method.
229 245
230This 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
231into 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
… …
243many seconds pass without a successful read or write on the underlying 259many seconds pass without a successful read or write on the underlying
244file 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
245will 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>
246error will be raised). 262error will be raised).
247 263
248There are three variants of the timeouts that work fully independent 264There are three variants of the timeouts that work independently of each
249of 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:
250C<timeout>, C<rtimeout> and C<wtimeout>, with corresponding callbacks 267C<timeout>, C<rtimeout> and C<wtimeout>, with corresponding callbacks
251C<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
252C<timeout_reset>, C<rtimeout_reset>, and C<wtimeout_reset>. 269C<timeout_reset>, C<rtimeout_reset>, and C<wtimeout_reset>.
253 270
254Note 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
255any outstanding read or write requests: If you plan to keep the connection 272outstanding read or write requests: If you plan to keep the connection
256idle then you should disable the timout temporarily or ignore the timeout 273idle then you should disable the timeout temporarily or ignore the
257in the C<on_timeout> callback, in which case AnyEvent::Handle will simply 274timeout in the corresponding C<on_timeout> callback, in which case
258restart the timeout. 275AnyEvent::Handle will simply restart the timeout.
259 276
260Zero (the default) disables this timeout. 277Zero (the default) disables the corresponding timeout.
261 278
262=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)
263 284
264Called whenever the inactivity timeout passes. If you return from this 285Called whenever the inactivity timeout passes. If you return from this
265callback, 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,
266so this condition is not fatal in any way. 287so this condition is not fatal in any way.
267 288
… …
275be 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
276(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
277amount 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
278isn't finished). 299isn't finished).
279 300
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
280=item autocork => <boolean> 316=item autocork => <boolean>
281 317
282When disabled (the default), then C<push_write> will try to immediately 318When disabled (the default), C<push_write> will try to immediately
283write 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
284a 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
285be inefficient if you write multiple small chunks (on the wire, this 321be inefficient if you write multiple small chunks (on the wire, this
286disadvantage is usually avoided by your kernel's nagle algorithm, see 322disadvantage is usually avoided by your kernel's nagle algorithm, see
287C<no_delay>, but this option can save costly syscalls). 323C<no_delay>, but this option can save costly syscalls).
288 324
289When enabled, then writes will always be queued till the next event loop 325When enabled, writes will always be queued till the next event loop
290iteration. This is efficient when you do many small writes per iteration, 326iteration. This is efficient when you do many small writes per iteration,
291but 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
292the write buffer often is full). It also increases write latency. 328the write buffer often is full). It also increases write latency.
293 329
294=item no_delay => <boolean> 330=item no_delay => <boolean>
… …
298the Nagle algorithm, and usually it is beneficial. 334the Nagle algorithm, and usually it is beneficial.
299 335
300In 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
301accomplishd by setting this option to a true value. 337accomplishd by setting this option to a true value.
302 338
303The default is your opertaing system's default behaviour (most likely 339The default is your operating system's default behaviour (most likely
304enabled), this option explicitly enables or disables it, if possible. 340enabled). This option explicitly enables or disables it, if possible.
305 341
306=item keepalive => <boolean> 342=item keepalive => <boolean>
307 343
308Enables (default disable) the SO_KEEPALIVE option on the stream socket: 344Enables (default disable) the SO_KEEPALIVE option on the stream socket:
309normally, TCP connections have no time-out once established, so TCP 345normally, TCP connections have no time-out once established, so TCP
310connections, once established, can stay alive forever even when the other 346connections, once established, can stay alive forever even when the other
311side 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
312TCP connections whent he other side becomes unreachable. While the default 348TCP connections when the other side becomes unreachable. While the default
313is OS-dependent, TCP keepalives usually kick in after around two hours, 349is OS-dependent, TCP keepalives usually kick in after around two hours,
314and, 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
315to 15 minutes later. 351to 15 minutes later.
316 352
317It 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
… …
335already 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
336from most attacks. 372from most attacks.
337 373
338=item read_size => <bytes> 374=item read_size => <bytes>
339 375
340The default read block size (the amount of bytes this module will 376The initial read block size, the number of bytes this module will try
341try to read during each loop iteration, which affects memory 377to read during each loop iteration. Each handle object will consume
342requirements). 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.
343 388
344=item low_water_mark => <bytes> 389=item low_water_mark => <bytes>
345 390
346Sets 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
347buffer: 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
348considered empty. 393considered empty.
349 394
350Sometimes it can be beneficial (for performance reasons) to add data to 395Sometimes it can be beneficial (for performance reasons) to add data to
351the 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
352the operating system kernel usually buffers data as well, so the default 397the operating system kernel usually buffers data as well, so the default
353is good in almost all cases. 398is good in almost all cases.
354 399
355=item linger => <seconds> 400=item linger => <seconds>
356 401
357If non-zero (default: C<3600>), then the destructor of the 402If this is non-zero (default: C<3600>), the destructor of the
358AnyEvent::Handle object will check whether there is still outstanding 403AnyEvent::Handle object will check whether there is still outstanding
359write 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
360socket. No errors will be reported (this mostly matches how the operating 405socket. No errors will be reported (this mostly matches how the operating
361system treats outstanding data at socket close time). 406system treats outstanding data at socket close time).
362 407
… …
369A string used to identify the remote site - usually the DNS hostname 414A string used to identify the remote site - usually the DNS hostname
370(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.
371 416
372Apart 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
373peername verification (see C<verify_peername> in L<AnyEvent::TLS>). This 418peername verification (see C<verify_peername> in L<AnyEvent::TLS>). This
374verification will be skipped when C<peername> is not specified or 419verification will be skipped when C<peername> is not specified or is
375C<undef>. 420C<undef>.
376 421
377=item tls => "accept" | "connect" | Net::SSLeay::SSL object 422=item tls => "accept" | "connect" | Net::SSLeay::SSL object
378 423
379When this parameter is given, it enables TLS (SSL) mode, that means 424When this parameter is given, it enables TLS (SSL) mode, that means
… …
384appropriate error message. 429appropriate error message.
385 430
386TLS mode requires Net::SSLeay to be installed (it will be loaded 431TLS mode requires Net::SSLeay to be installed (it will be loaded
387automatically 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
388have 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
389to 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.
390 436
391Unlike 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
392C<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>
393mode. 439mode.
394 440
… …
405B<IMPORTANT:> since Net::SSLeay "objects" are really only integers, 451B<IMPORTANT:> since Net::SSLeay "objects" are really only integers,
406passing 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
407happens 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
408segmentation fault. 454segmentation fault.
409 455
410See 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.
411 457
412=item tls_ctx => $anyevent_tls 458=item tls_ctx => $anyevent_tls
413 459
414Use 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
415(unless a connection object was specified directly). If this parameter is 461(unless a connection object was specified directly). If this
416missing, 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>.
417 464
418Instead 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
419=> 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
420new TLS context object. 467new TLS context object.
421 468
… …
430 477
431TLS 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
432callback 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>.
433 480
434Without this callback, handshake failures lead to C<on_error> being 481Without this callback, handshake failures lead to C<on_error> being
435called, as normal. 482called as usual.
436 483
437Note 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
438need 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
439then call C<< ->starttls >> again. 486then call C<< ->starttls >> again.
440 487
441=item on_stoptls => $cb->($handle) 488=item on_stoptls => $cb->($handle)
442 489
… …
490 $self->{connect}[0], 537 $self->{connect}[0],
491 $self->{connect}[1], 538 $self->{connect}[1],
492 sub { 539 sub {
493 my ($fh, $host, $port, $retry) = @_; 540 my ($fh, $host, $port, $retry) = @_;
494 541
542 delete $self->{_connect}; # no longer needed
543
495 if ($fh) { 544 if ($fh) {
496 $self->{fh} = $fh; 545 $self->{fh} = $fh;
497 546
498 delete $self->{_skip_drain_rbuf}; 547 delete $self->{_skip_drain_rbuf};
499 $self->_start; 548 $self->_start;
… …
506 }); 555 });
507 556
508 } else { 557 } else {
509 if ($self->{on_connect_error}) { 558 if ($self->{on_connect_error}) {
510 $self->{on_connect_error}($self, "$!"); 559 $self->{on_connect_error}($self, "$!");
511 $self->destroy; 560 $self->destroy if $self;
512 } else { 561 } else {
513 $self->_error ($!, 1); 562 $self->_error ($!, 1);
514 } 563 }
515 } 564 }
516 }, 565 },
517 sub { 566 sub {
518 local $self->{fh} = $_[0]; 567 local $self->{fh} = $_[0];
519 568
520 $self->{on_prepare} 569 $self->{on_prepare}
521 ? $self->{on_prepare}->($self) 570 ? $self->{on_prepare}->($self)
522 : () 571 : ()
523 } 572 }
524 ); 573 );
525 } 574 }
526 575
… …
532} 581}
533 582
534sub _start { 583sub _start {
535 my ($self) = @_; 584 my ($self) = @_;
536 585
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
537 AnyEvent::Util::fh_nonblocking $self->{fh}, 1; 592 AnyEvent::Util::fh_nonblocking $self->{fh}, 1;
538 593
539 $self->{_activity} = 594 $self->{_activity} =
540 $self->{_ractivity} = 595 $self->{_ractivity} =
541 $self->{_wactivity} = AE::now; 596 $self->{_wactivity} = AE::now;
542 597
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
543 $self->timeout (delete $self->{timeout} ) if $self->{timeout}; 602 $self->timeout (delete $self->{timeout} ) if $self->{timeout};
544 $self->rtimeout (delete $self->{rtimeout} ) if $self->{rtimeout}; 603 $self->rtimeout (delete $self->{rtimeout} ) if $self->{rtimeout};
545 $self->wtimeout (delete $self->{wtimeout} ) if $self->{wtimeout}; 604 $self->wtimeout (delete $self->{wtimeout} ) if $self->{wtimeout};
546 605
547 $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};
… …
550 $self->oobinline (exists $self->{oobinline} ? delete $self->{oobinline} : 1); 609 $self->oobinline (exists $self->{oobinline} ? delete $self->{oobinline} : 1);
551 610
552 $self->starttls (delete $self->{tls}, delete $self->{tls_ctx}) 611 $self->starttls (delete $self->{tls}, delete $self->{tls_ctx})
553 if $self->{tls}; 612 if $self->{tls};
554 613
555 $self->on_drain (delete $self->{on_drain}) if $self->{on_drain}; 614 $self->on_drain (delete $self->{on_drain} ) if $self->{on_drain};
556 615
557 $self->start_read 616 $self->start_read
558 if $self->{on_read} || @{ $self->{_queue} }; 617 if $self->{on_read} || @{ $self->{_queue} };
559 618
560 $self->_drain_wbuf; 619 $self->_drain_wbuf;
… …
567 $message ||= "$!"; 626 $message ||= "$!";
568 627
569 if ($self->{on_error}) { 628 if ($self->{on_error}) {
570 $self->{on_error}($self, $fatal, $message); 629 $self->{on_error}($self, $fatal, $message);
571 $self->destroy if $fatal; 630 $self->destroy if $fatal;
572 } elsif ($self->{fh}) { 631 } elsif ($self->{fh} || $self->{connect}) {
573 $self->destroy; 632 $self->destroy;
574 Carp::croak "AnyEvent::Handle uncaught error: $message"; 633 Carp::croak "AnyEvent::Handle uncaught error: $message";
575 } 634 }
576} 635}
577 636
… …
636=cut 695=cut
637 696
638sub no_delay { 697sub no_delay {
639 $_[0]{no_delay} = $_[1]; 698 $_[0]{no_delay} = $_[1];
640 699
641 eval {
642 local $SIG{__DIE__};
643 setsockopt $_[0]{fh}, Socket::IPPROTO_TCP (), Socket::TCP_NODELAY (), int $_[1] 700 setsockopt $_[0]{fh}, Socket::IPPROTO_TCP (), Socket::TCP_NODELAY (), int $_[1]
644 if $_[0]{fh}; 701 if $_[0]{fh};
645 };
646} 702}
647 703
648=item $handle->keepalive ($boolean) 704=item $handle->keepalive ($boolean)
649 705
650Enables or disables the C<keepalive> setting (see constructor argument of 706Enables or disables the C<keepalive> setting (see constructor argument of
… …
710 766
711Replace 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).
712 768
713=cut 769=cut
714 770
715sub on_starttls { 771sub on_stoptls {
716 $_[0]{on_stoptls} = $_[1]; 772 $_[0]{on_stoptls} = $_[1];
717} 773}
718 774
719=item $handle->rbuf_max ($max_octets) 775=item $handle->rbuf_max ($max_octets)
720 776
721Configures 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).
722 782
723=cut 783=cut
724 784
725sub rbuf_max { 785sub rbuf_max {
726 $_[0]{rbuf_max} = $_[1]; 786 $_[0]{rbuf_max} = $_[1];
727} 787}
728 788
789sub wbuf_max {
790 $_[0]{wbuf_max} = $_[1];
791}
792
729############################################################################# 793#############################################################################
730 794
731=item $handle->timeout ($seconds) 795=item $handle->timeout ($seconds)
732 796
733=item $handle->rtimeout ($seconds) 797=item $handle->rtimeout ($seconds)
734 798
735=item $handle->wtimeout ($seconds) 799=item $handle->wtimeout ($seconds)
736 800
737Configures (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.
738 805
739=item $handle->timeout_reset 806=item $handle->timeout_reset
740 807
741=item $handle->rtimeout_reset 808=item $handle->rtimeout_reset
742 809
… …
759 $_[0]{$on_timeout} = $_[1]; 826 $_[0]{$on_timeout} = $_[1];
760 }; 827 };
761 828
762 *$timeout = sub { 829 *$timeout = sub {
763 my ($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";
764 834
765 $self->{$timeout} = $new_value; 835 $self->{$timeout} = $new_value;
766 delete $self->{$tw}; &$cb; 836 delete $self->{$tw}; &$cb;
767 }; 837 };
768 838
… …
823 893
824The 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
825AnyEvent::Handle will automatically try to get rid of it for you. 895AnyEvent::Handle will automatically try to get rid of it for you.
826 896
827When 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
828water mark, the C<on_drain> callback will be invoked. 898water mark, the C<on_drain> callback will be invoked once.
829 899
830=over 4 900=over 4
831 901
832=item $handle->on_drain ($cb) 902=item $handle->on_drain ($cb)
833 903
834Sets 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
835C<on_drain> in the constructor). 905C<on_drain> in the constructor).
836 906
907This method may invoke callbacks (and therefore the handle might be
908destroyed after it returns).
909
837=cut 910=cut
838 911
839sub on_drain { 912sub on_drain {
840 my ($self, $cb) = @_; 913 my ($self, $cb) = @_;
841 914
… …
845 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});
846} 919}
847 920
848=item $handle->push_write ($data) 921=item $handle->push_write ($data)
849 922
850Queues 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
851want (only limited by the available memory), as C<AnyEvent::Handle> 924you want (only limited by the available memory and C<wbuf_max>), as
852buffers 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).
853 929
854=cut 930=cut
855 931
856sub _drain_wbuf { 932sub _drain_wbuf {
857 my ($self) = @_; 933 my ($self) = @_;
… …
882 $cb->() unless $self->{autocork}; 958 $cb->() unless $self->{autocork};
883 959
884 # if still data left in wbuf, we need to poll 960 # if still data left in wbuf, we need to poll
885 $self->{_ww} = AE::io $self->{fh}, 1, $cb 961 $self->{_ww} = AE::io $self->{fh}, 1, $cb
886 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 $self->_error (Errno::ENOSPC, 1), return;
969 }
887 }; 970 };
888} 971}
889 972
890our %WH; 973our %WH;
891 974
… …
903 @_ = ($WH{$type} ||= _load_func "$type\::anyevent_write_type" 986 @_ = ($WH{$type} ||= _load_func "$type\::anyevent_write_type"
904 or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::push_write") 987 or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::push_write")
905 ->($self, @_); 988 ->($self, @_);
906 } 989 }
907 990
991 # we downgrade here to avoid hard-to-track-down bugs,
992 # and diagnose the problem earlier and better.
993
908 if ($self->{tls}) { 994 if ($self->{tls}) {
909 $self->{_tls_wbuf} .= $_[0]; 995 utf8::downgrade $self->{_tls_wbuf} .= $_[0];
910 &_dotls ($self) if $self->{fh}; 996 &_dotls ($self) if $self->{fh};
911 } else { 997 } else {
912 $self->{wbuf} .= $_[0]; 998 utf8::downgrade $self->{wbuf} .= $_[0];
913 $self->_drain_wbuf if $self->{fh}; 999 $self->_drain_wbuf if $self->{fh};
914 } 1000 }
915} 1001}
916 1002
917=item $handle->push_write (type => @args) 1003=item $handle->push_write (type => @args)
918 1004
919Instead of formatting your data yourself, you can also let this module 1005Instead of formatting your data yourself, you can also let this module
920do the job by specifying a type and type-specific arguments. You 1006do the job by specifying a type and type-specific arguments. You
921can also specify the (fully qualified) name of a package, in which 1007can also specify the (fully qualified) name of a package, in which
922case AnyEvent tries to load the package and then expects to find the 1008case AnyEvent tries to load the package and then expects to find the
923C<anyevent_read_type> function inside (see "custom write types", below). 1009C<anyevent_write_type> function inside (see "custom write types", below).
924 1010
925Predefined types are (if you have ideas for additional types, feel free to 1011Predefined types are (if you have ideas for additional types, feel free to
926drop by and tell us): 1012drop by and tell us):
927 1013
928=over 4 1014=over 4
… …
1008=cut 1094=cut
1009 1095
1010register_write_type storable => sub { 1096register_write_type storable => sub {
1011 my ($self, $ref) = @_; 1097 my ($self, $ref) = @_;
1012 1098
1013 require Storable; 1099 require Storable unless $Storable::VERSION;
1014 1100
1015 pack "w/a*", Storable::nfreeze ($ref) 1101 pack "w/a*", Storable::nfreeze ($ref)
1016}; 1102};
1017 1103
1018=back 1104=back
… …
1023before 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
1024C<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
1025C<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
1026replaces the C<on_drain> callback with: 1112replaces the C<on_drain> callback with:
1027 1113
1028 sub { shutdown $_[0]{fh}, 1 } # for push_shutdown 1114 sub { shutdown $_[0]{fh}, 1 }
1029 1115
1030This simply shuts down the write side and signals an EOF condition to the 1116This simply shuts down the write side and signals an EOF condition to the
1031the peer. 1117the peer.
1032 1118
1033You can rely on the normal read queue and C<on_eof> handling 1119You can rely on the normal read queue and C<on_eof> handling
1034afterwards. This is the cleanest way to close a connection. 1120afterwards. This is the cleanest way to close a connection.
1121
1122This method may invoke callbacks (and therefore the handle might be
1123destroyed after it returns).
1035 1124
1036=cut 1125=cut
1037 1126
1038sub push_shutdown { 1127sub push_shutdown {
1039 my ($self) = @_; 1128 my ($self) = @_;
… …
1052 1141
1053Whenever 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
1054the handle object and the remaining arguments. 1143the handle object and the remaining arguments.
1055 1144
1056The 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
1057appended 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
1058"arguments to on-the-wire-format" converter. 1147"arguments to on-the-wire-format" converter.
1059 1148
1060Example: implement a custom write type C<join> that joins the remaining 1149Example: implement a custom write type C<join> that joins the remaining
1061arguments using the first one. 1150arguments using the first one.
1062 1151
… …
1089ways, 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
1090a queue. 1179a queue.
1091 1180
1092In 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
1093new 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
1094enough is there) from the read buffer (C<< $handle->rbuf >>). Or you cna 1183enough is there) from the read buffer (C<< $handle->rbuf >>). Or you can
1095leave the data there if you want to accumulate more (e.g. when only a 1184leave the data there if you want to accumulate more (e.g. when only a
1096partial message has been received so far). 1185partial message has been received so far), or change the read queue with
1186e.g. C<push_read>.
1097 1187
1098In the more complex case, you want to queue multiple callbacks. In this 1188In the more complex case, you want to queue multiple callbacks. In this
1099case, AnyEvent::Handle will call the first queued callback each time new 1189case, AnyEvent::Handle will call the first queued callback each time new
1100data arrives (also the first time it is queued) and removes it when it has 1190data arrives (also the first time it is queued) and remove it when it has
1101done its job (see C<push_read>, below). 1191done its job (see C<push_read>, below).
1102 1192
1103This way you can, for example, push three line-reads, followed by reading 1193This way you can, for example, push three line-reads, followed by reading
1104a chunk of data, and AnyEvent::Handle will execute them in order. 1194a chunk of data, and AnyEvent::Handle will execute them in order.
1105 1195
… …
1236 1326
1237This replaces the currently set C<on_read> callback, or clears it (when 1327This replaces the currently set C<on_read> callback, or clears it (when
1238the new callback is C<undef>). See the description of C<on_read> in the 1328the new callback is C<undef>). See the description of C<on_read> in the
1239constructor. 1329constructor.
1240 1330
1331This method may invoke callbacks (and therefore the handle might be
1332destroyed after it returns).
1333
1241=cut 1334=cut
1242 1335
1243sub on_read { 1336sub on_read {
1244 my ($self, $cb) = @_; 1337 my ($self, $cb) = @_;
1245 1338
… …
1247 $self->_drain_rbuf if $cb; 1340 $self->_drain_rbuf if $cb;
1248} 1341}
1249 1342
1250=item $handle->rbuf 1343=item $handle->rbuf
1251 1344
1252Returns 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).
1253 1348
1254You can access the read buffer directly as the C<< ->{rbuf} >> 1349The only operation allowed on the read buffer (apart from looking at it)
1255member, if you want. However, the only operation allowed on the 1350is removing data from its beginning. Otherwise modifying or appending to
1256read buffer (apart from looking at it) is removing data from its 1351it is not allowed and will lead to hard-to-track-down bugs.
1257beginning. Otherwise modifying or appending to it is not allowed and will
1258lead to hard-to-track-down bugs.
1259 1352
1260NOTE: 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>
1261C<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
1262automatically 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.
1263 1357
1264=cut 1358=cut
1265 1359
1266sub rbuf : lvalue { 1360sub rbuf : lvalue {
1267 $_[0]{rbuf} 1361 $_[0]{rbuf}
… …
1284 1378
1285If 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
1286interested 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
1287true, it will be removed from the queue. 1381true, it will be removed from the queue.
1288 1382
1383These methods may invoke callbacks (and therefore the handle might be
1384destroyed after it returns).
1385
1289=cut 1386=cut
1290 1387
1291our %RH; 1388our %RH;
1292 1389
1293sub register_read_type($$) { 1390sub register_read_type($$) {
… …
1315 my $cb = pop; 1412 my $cb = pop;
1316 1413
1317 if (@_) { 1414 if (@_) {
1318 my $type = shift; 1415 my $type = shift;
1319 1416
1417 $cb = ($RH{$type} ||= _load_func "$type\::anyevent_read_type"
1320 $cb = ($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")
1321 ->($self, $cb, @_); 1419 ->($self, $cb, @_);
1322 } 1420 }
1323 1421
1324 unshift @{ $self->{_queue} }, $cb; 1422 unshift @{ $self->{_queue} }, $cb;
1325 $self->_drain_rbuf; 1423 $self->_drain_rbuf;
… …
1347data. 1445data.
1348 1446
1349Example: read 2 bytes. 1447Example: read 2 bytes.
1350 1448
1351 $handle->push_read (chunk => 2, sub { 1449 $handle->push_read (chunk => 2, sub {
1352 warn "yay ", unpack "H*", $_[1]; 1450 say "yay " . unpack "H*", $_[1];
1353 }); 1451 });
1354 1452
1355=cut 1453=cut
1356 1454
1357register_read_type chunk => sub { 1455register_read_type chunk => sub {
… …
1387 1485
1388register_read_type line => sub { 1486register_read_type line => sub {
1389 my ($self, $cb, $eol) = @_; 1487 my ($self, $cb, $eol) = @_;
1390 1488
1391 if (@_ < 3) { 1489 if (@_ < 3) {
1392 # this is more than twice as fast as the generic code below 1490 # this is faster then the generic code below
1393 sub { 1491 sub {
1394 $_[0]{rbuf} =~ s/^([^\015\012]*)(\015?\012)// or return; 1492 (my $pos = index $_[0]{rbuf}, "\012") >= 0
1493 or return;
1395 1494
1495 (my $str = substr $_[0]{rbuf}, 0, $pos + 1, "") =~ s/(\015?\012)\Z// or die;
1396 $cb->($_[0], $1, $2); 1496 $cb->($_[0], $str, "$1");
1397 1 1497 1
1398 } 1498 }
1399 } else { 1499 } else {
1400 $eol = quotemeta $eol unless ref $eol; 1500 $eol = quotemeta $eol unless ref $eol;
1401 $eol = qr|^(.*?)($eol)|s; 1501 $eol = qr|^(.*?)($eol)|s;
1402 1502
1403 sub { 1503 sub {
1404 $_[0]{rbuf} =~ s/$eol// or return; 1504 $_[0]{rbuf} =~ s/$eol// or return;
1405 1505
1406 $cb->($_[0], $1, $2); 1506 $cb->($_[0], "$1", "$2");
1407 1 1507 1
1408 } 1508 }
1409 } 1509 }
1410}; 1510};
1411 1511
… …
1433the receive buffer when neither C<$accept> nor C<$reject> match, 1533the receive buffer when neither C<$accept> nor C<$reject> match,
1434and everything preceding and including the match will be accepted 1534and everything preceding and including the match will be accepted
1435unconditionally. This is useful to skip large amounts of data that you 1535unconditionally. This is useful to skip large amounts of data that you
1436know cannot be matched, so that the C<$accept> or C<$reject> regex do not 1536know cannot be matched, so that the C<$accept> or C<$reject> regex do not
1437have to start matching from the beginning. This is purely an optimisation 1537have to start matching from the beginning. This is purely an optimisation
1438and is usually worth only when you expect more than a few kilobytes. 1538and is usually worth it only when you expect more than a few kilobytes.
1439 1539
1440Example: expect a http header, which ends at C<\015\012\015\012>. Since we 1540Example: expect a http header, which ends at C<\015\012\015\012>. Since we
1441expect the header to be very large (it isn't in practise, but...), we use 1541expect the header to be very large (it isn't in practice, but...), we use
1442a skip regex to skip initial portions. The skip regex is tricky in that 1542a skip regex to skip initial portions. The skip regex is tricky in that
1443it only accepts something not ending in either \015 or \012, as these are 1543it only accepts something not ending in either \015 or \012, as these are
1444required for the accept regex. 1544required for the accept regex.
1445 1545
1446 $handle->push_read (regex => 1546 $handle->push_read (regex =>
… …
1459 1559
1460 sub { 1560 sub {
1461 # accept 1561 # accept
1462 if ($$rbuf =~ $accept) { 1562 if ($$rbuf =~ $accept) {
1463 $data .= substr $$rbuf, 0, $+[0], ""; 1563 $data .= substr $$rbuf, 0, $+[0], "";
1464 $cb->($self, $data); 1564 $cb->($_[0], $data);
1465 return 1; 1565 return 1;
1466 } 1566 }
1467 1567
1468 # reject 1568 # reject
1469 if ($reject && $$rbuf =~ $reject) { 1569 if ($reject && $$rbuf =~ $reject) {
1470 $self->_error (Errno::EBADMSG); 1570 $_[0]->_error (Errno::EBADMSG);
1471 } 1571 }
1472 1572
1473 # skip 1573 # skip
1474 if ($skip && $$rbuf =~ $skip) { 1574 if ($skip && $$rbuf =~ $skip) {
1475 $data .= substr $$rbuf, 0, $+[0], ""; 1575 $data .= substr $$rbuf, 0, $+[0], "";
… …
1491 my ($self, $cb) = @_; 1591 my ($self, $cb) = @_;
1492 1592
1493 sub { 1593 sub {
1494 unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) { 1594 unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
1495 if ($_[0]{rbuf} =~ /[^0-9]/) { 1595 if ($_[0]{rbuf} =~ /[^0-9]/) {
1496 $self->_error (Errno::EBADMSG); 1596 $_[0]->_error (Errno::EBADMSG);
1497 } 1597 }
1498 return; 1598 return;
1499 } 1599 }
1500 1600
1501 my $len = $1; 1601 my $len = $1;
1502 1602
1503 $self->unshift_read (chunk => $len, sub { 1603 $_[0]->unshift_read (chunk => $len, sub {
1504 my $string = $_[1]; 1604 my $string = $_[1];
1505 $_[0]->unshift_read (chunk => 1, sub { 1605 $_[0]->unshift_read (chunk => 1, sub {
1506 if ($_[1] eq ",") { 1606 if ($_[1] eq ",") {
1507 $cb->($_[0], $string); 1607 $cb->($_[0], $string);
1508 } else { 1608 } else {
1509 $self->_error (Errno::EBADMSG); 1609 $_[0]->_error (Errno::EBADMSG);
1510 } 1610 }
1511 }); 1611 });
1512 }); 1612 });
1513 1613
1514 1 1614 1
… …
1587 1687
1588 my $data; 1688 my $data;
1589 my $rbuf = \$self->{rbuf}; 1689 my $rbuf = \$self->{rbuf};
1590 1690
1591 sub { 1691 sub {
1592 my $ref = eval { $json->incr_parse ($self->{rbuf}) }; 1692 my $ref = eval { $json->incr_parse ($_[0]{rbuf}) };
1593 1693
1594 if ($ref) { 1694 if ($ref) {
1595 $self->{rbuf} = $json->incr_text; 1695 $_[0]{rbuf} = $json->incr_text;
1596 $json->incr_text = ""; 1696 $json->incr_text = "";
1597 $cb->($self, $ref); 1697 $cb->($_[0], $ref);
1598 1698
1599 1 1699 1
1600 } elsif ($@) { 1700 } elsif ($@) {
1601 # error case 1701 # error case
1602 $json->incr_skip; 1702 $json->incr_skip;
1603 1703
1604 $self->{rbuf} = $json->incr_text; 1704 $_[0]{rbuf} = $json->incr_text;
1605 $json->incr_text = ""; 1705 $json->incr_text = "";
1606 1706
1607 $self->_error (Errno::EBADMSG); 1707 $_[0]->_error (Errno::EBADMSG);
1608 1708
1609 () 1709 ()
1610 } else { 1710 } else {
1611 $self->{rbuf} = ""; 1711 $_[0]{rbuf} = "";
1612 1712
1613 () 1713 ()
1614 } 1714 }
1615 } 1715 }
1616}; 1716};
… …
1626=cut 1726=cut
1627 1727
1628register_read_type storable => sub { 1728register_read_type storable => sub {
1629 my ($self, $cb) = @_; 1729 my ($self, $cb) = @_;
1630 1730
1631 require Storable; 1731 require Storable unless $Storable::VERSION;
1632 1732
1633 sub { 1733 sub {
1634 # when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method 1734 # when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
1635 defined (my $len = eval { unpack "w", $_[0]{rbuf} }) 1735 defined (my $len = eval { unpack "w", $_[0]{rbuf} })
1636 or return; 1736 or return;
… …
1639 1739
1640 # bypass unshift if we already have the remaining chunk 1740 # bypass unshift if we already have the remaining chunk
1641 if ($format + $len <= length $_[0]{rbuf}) { 1741 if ($format + $len <= length $_[0]{rbuf}) {
1642 my $data = substr $_[0]{rbuf}, $format, $len; 1742 my $data = substr $_[0]{rbuf}, $format, $len;
1643 substr $_[0]{rbuf}, 0, $format + $len, ""; 1743 substr $_[0]{rbuf}, 0, $format + $len, "";
1744
1644 $cb->($_[0], Storable::thaw ($data)); 1745 eval { $cb->($_[0], Storable::thaw ($data)); 1 }
1746 or return $_[0]->_error (Errno::EBADMSG);
1645 } else { 1747 } else {
1646 # remove prefix 1748 # remove prefix
1647 substr $_[0]{rbuf}, 0, $format, ""; 1749 substr $_[0]{rbuf}, 0, $format, "";
1648 1750
1649 # read remaining chunk 1751 # read remaining chunk
1650 $_[0]->unshift_read (chunk => $len, sub { 1752 $_[0]->unshift_read (chunk => $len, sub {
1651 if (my $ref = eval { Storable::thaw ($_[1]) }) { 1753 eval { $cb->($_[0], Storable::thaw ($_[1])); 1 }
1652 $cb->($_[0], $ref);
1653 } else {
1654 $self->_error (Errno::EBADMSG); 1754 or $_[0]->_error (Errno::EBADMSG);
1655 }
1656 }); 1755 });
1657 } 1756 }
1658 1757
1659 1 1758 1
1660 } 1759 }
1760};
1761
1762=item tls_detect => $cb->($handle, $detect, $major, $minor)
1763
1764Checks the input stream for a valid SSL or TLS handshake TLSPaintext
1765record without consuming anything. Only SSL version 3 or higher
1766is handled, up to the fictituous protocol 4.x (but both SSL3+ and
1767SSL2-compatible framing is supported).
1768
1769If it detects that the input data is likely TLS, it calls the callback
1770with a true value for C<$detect> and the (on-wire) TLS version as second
1771and third argument (C<$major> is C<3>, and C<$minor> is 0..3 for SSL
17723.0, TLS 1.0, 1.1 and 1.2, respectively). If it detects the input to
1773be definitely not TLS, it calls the callback with a false value for
1774C<$detect>.
1775
1776The callback could use this information to decide whether or not to start
1777TLS negotiation.
1778
1779In all cases the data read so far is passed to the following read
1780handlers.
1781
1782Usually you want to use the C<tls_autostart> read type instead.
1783
1784If you want to design a protocol that works in the presence of TLS
1785dtection, make sure that any non-TLS data doesn't start with the octet 22
1786(ASCII SYN, 16 hex) or 128-255 (i.e. highest bit set). The checks this
1787read type does are a bit more strict, but might losen in the future to
1788accomodate protocol changes.
1789
1790This read type does not rely on L<AnyEvent::TLS> (and thus, not on
1791L<Net::SSLeay>).
1792
1793=item tls_autostart => $tls[, $tls_ctx]
1794
1795Tries to detect a valid SSL or TLS handshake. If one is detected, it tries
1796to start tls by calling C<starttls> with the given arguments.
1797
1798In practise, C<$tls> must be C<accept>, or a Net::SSLeay context that has
1799been configured to accept, as servers do not normally send a handshake on
1800their own and ths cannot be detected in this way.
1801
1802See C<tls_detect> above for more details.
1803
1804Example: give the client a chance to start TLS before accepting a text
1805line.
1806
1807 $hdl->push_read (tls_detect => "accept");
1808 $hdl->push_read (line => sub {
1809 print "received ", ($_[0]{tls} ? "encrypted" : "cleartext"), " <$_[1]>\n";
1810 });
1811
1812=cut
1813
1814register_read_type tls_detect => sub {
1815 my ($self, $cb) = @_;
1816
1817 sub {
1818 # this regex matches a full or partial tls record
1819 if (
1820 # ssl3+: type(22=handshake) major(=3) minor(any) length_hi
1821 $self->{rbuf} =~ /^(?:\z| \x16 (\z| [\x03\x04] (?:\z| . (?:\z| [\x00-\x40] ))))/xs
1822 # ssl2 comapatible: len_hi len_lo type(1) major minor dummy(forlength)
1823 or $self->{rbuf} =~ /^(?:\z| [\x80-\xff] (?:\z| . (?:\z| \x01 (\z| [\x03\x04] (?:\z| . (?:\z| . ))))))/xs
1824 ) {
1825 return if 3 != length $1; # partial match, can't decide yet
1826
1827 # full match, valid TLS record
1828 my ($major, $minor) = unpack "CC", $1;
1829 $cb->($self, "accept", $major + $minor * 0.1);
1830 } else {
1831 # mismatch == guaranteed not TLS
1832 $cb->($self, undef);
1833 }
1834
1835 1
1836 }
1837};
1838
1839register_read_type tls_autostart => sub {
1840 my ($self, @tls) = @_;
1841
1842 $RH{tls_detect}($self, sub {
1843 return unless $_[1];
1844 $_[0]->starttls (@tls);
1845 })
1661}; 1846};
1662 1847
1663=back 1848=back
1664 1849
1665=item custom read types - Package::anyevent_read_type $handle, $cb, @args 1850=item custom read types - Package::anyevent_read_type $handle, $cb, @args
… …
1697Note that AnyEvent::Handle will automatically C<start_read> for you when 1882Note that AnyEvent::Handle will automatically C<start_read> for you when
1698you change the C<on_read> callback or push/unshift a read callback, and it 1883you change the C<on_read> callback or push/unshift a read callback, and it
1699will automatically C<stop_read> for you when neither C<on_read> is set nor 1884will automatically C<stop_read> for you when neither C<on_read> is set nor
1700there are any read requests in the queue. 1885there are any read requests in the queue.
1701 1886
1702These methods will have no effect when in TLS mode (as TLS doesn't support 1887In older versions of this module (<= 5.3), these methods had no effect,
1703half-duplex connections). 1888as TLS does not support half-duplex connections. In current versions they
1889work as expected, as this behaviour is required to avoid certain resource
1890attacks, where the program would be forced to read (and buffer) arbitrary
1891amounts of data before being able to send some data. The drawback is that
1892some readings of the the SSL/TLS specifications basically require this
1893attack to be working, as SSL/TLS implementations might stall sending data
1894during a rehandshake.
1895
1896As a guideline, during the initial handshake, you should not stop reading,
1897and as a client, it might cause problems, depending on your application.
1704 1898
1705=cut 1899=cut
1706 1900
1707sub stop_read { 1901sub stop_read {
1708 my ($self) = @_; 1902 my ($self) = @_;
1709 1903
1710 delete $self->{_rw} unless $self->{tls}; 1904 delete $self->{_rw};
1711} 1905}
1712 1906
1713sub start_read { 1907sub start_read {
1714 my ($self) = @_; 1908 my ($self) = @_;
1715 1909
1716 unless ($self->{_rw} || $self->{_eof}) { 1910 unless ($self->{_rw} || $self->{_eof} || !$self->{fh}) {
1717 Scalar::Util::weaken $self; 1911 Scalar::Util::weaken $self;
1718 1912
1719 $self->{_rw} = AE::io $self->{fh}, 0, sub { 1913 $self->{_rw} = AE::io $self->{fh}, 0, sub {
1720 my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf}); 1914 my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf});
1721 my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf; 1915 my $len = sysread $self->{fh}, $$rbuf, $self->{read_size}, length $$rbuf;
1722 1916
1723 if ($len > 0) { 1917 if ($len > 0) {
1724 $self->{_activity} = $self->{_ractivity} = AE::now; 1918 $self->{_activity} = $self->{_ractivity} = AE::now;
1725 1919
1726 if ($self->{tls}) { 1920 if ($self->{tls}) {
… …
1729 &_dotls ($self); 1923 &_dotls ($self);
1730 } else { 1924 } else {
1731 $self->_drain_rbuf; 1925 $self->_drain_rbuf;
1732 } 1926 }
1733 1927
1928 if ($len == $self->{read_size}) {
1929 $self->{read_size} *= 2;
1930 $self->{read_size} = $self->{max_read_size} || MAX_READ_SIZE
1931 if $self->{read_size} > ($self->{max_read_size} || MAX_READ_SIZE);
1932 }
1933
1734 } elsif (defined $len) { 1934 } elsif (defined $len) {
1735 delete $self->{_rw}; 1935 delete $self->{_rw};
1736 $self->{_eof} = 1; 1936 $self->{_eof} = 1;
1737 $self->_drain_rbuf; 1937 $self->_drain_rbuf;
1738 1938
… …
1750 my ($self, $err) = @_; 1950 my ($self, $err) = @_;
1751 1951
1752 return $self->_error ($!, 1) 1952 return $self->_error ($!, 1)
1753 if $err == Net::SSLeay::ERROR_SYSCALL (); 1953 if $err == Net::SSLeay::ERROR_SYSCALL ();
1754 1954
1755 my $err =Net::SSLeay::ERR_error_string (Net::SSLeay::ERR_get_error ()); 1955 my $err = Net::SSLeay::ERR_error_string (Net::SSLeay::ERR_get_error ());
1756 1956
1757 # reduce error string to look less scary 1957 # reduce error string to look less scary
1758 $err =~ s/^error:[0-9a-fA-F]{8}:[^:]+:([^:]+):/\L$1: /; 1958 $err =~ s/^error:[0-9a-fA-F]{8}:[^:]+:([^:]+):/\L$1: /;
1759 1959
1760 if ($self->{_on_starttls}) { 1960 if ($self->{_on_starttls}) {
… …
1814 && ($tmp != $ERROR_SYSCALL || $!); 2014 && ($tmp != $ERROR_SYSCALL || $!);
1815 2015
1816 while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) { 2016 while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) {
1817 $self->{wbuf} .= $tmp; 2017 $self->{wbuf} .= $tmp;
1818 $self->_drain_wbuf; 2018 $self->_drain_wbuf;
2019 $self->{tls} or return; # tls session might have gone away in callback
1819 } 2020 }
1820 2021
1821 $self->{_on_starttls} 2022 $self->{_on_starttls}
1822 and Net::SSLeay::state ($self->{tls}) == Net::SSLeay::ST_OK () 2023 and Net::SSLeay::state ($self->{tls}) == Net::SSLeay::ST_OK ()
1823 and (delete $self->{_on_starttls})->($self, 1, "TLS/SSL connection established"); 2024 and (delete $self->{_on_starttls})->($self, 1, "TLS/SSL connection established");
… …
1825 2026
1826=item $handle->starttls ($tls[, $tls_ctx]) 2027=item $handle->starttls ($tls[, $tls_ctx])
1827 2028
1828Instead of starting TLS negotiation immediately when the AnyEvent::Handle 2029Instead of starting TLS negotiation immediately when the AnyEvent::Handle
1829object is created, you can also do that at a later time by calling 2030object is created, you can also do that at a later time by calling
1830C<starttls>. 2031C<starttls>. See the C<tls> constructor argument for general info.
1831 2032
1832Starting TLS is currently an asynchronous operation - when you push some 2033Starting TLS is currently an asynchronous operation - when you push some
1833write data and then call C<< ->starttls >> then TLS negotiation will start 2034write data and then call C<< ->starttls >> then TLS negotiation will start
1834immediately, after which the queued write data is then sent. 2035immediately, after which the queued write data is then sent. This might
2036change in future versions, so best make sure you have no outstanding write
2037data when calling this method.
1835 2038
1836The first argument is the same as the C<tls> constructor argument (either 2039The first argument is the same as the C<tls> constructor argument (either
1837C<"connect">, C<"accept"> or an existing Net::SSLeay object). 2040C<"connect">, C<"accept"> or an existing Net::SSLeay object).
1838 2041
1839The second argument is the optional C<AnyEvent::TLS> object that is used 2042The second argument is the optional C<AnyEvent::TLS> object that is used
… …
1845context in C<< $handle->{tls_ctx} >> after this call and can be used or 2048context in C<< $handle->{tls_ctx} >> after this call and can be used or
1846changed to your liking. Note that the handshake might have already started 2049changed to your liking. Note that the handshake might have already started
1847when this function returns. 2050when this function returns.
1848 2051
1849Due to bugs in OpenSSL, it might or might not be possible to do multiple 2052Due to bugs in OpenSSL, it might or might not be possible to do multiple
1850handshakes on the same stream. Best do not attempt to use the stream after 2053handshakes on the same stream. It is best to not attempt to use the
1851stopping TLS. 2054stream after stopping TLS.
2055
2056This method may invoke callbacks (and therefore the handle might be
2057destroyed after it returns).
1852 2058
1853=cut 2059=cut
1854 2060
1855our %TLS_CACHE; #TODO not yet documented, should we? 2061our %TLS_CACHE; #TODO not yet documented, should we?
1856 2062
… …
1858 my ($self, $tls, $ctx) = @_; 2064 my ($self, $tls, $ctx) = @_;
1859 2065
1860 Carp::croak "It is an error to call starttls on an AnyEvent::Handle object while TLS is already active, caught" 2066 Carp::croak "It is an error to call starttls on an AnyEvent::Handle object while TLS is already active, caught"
1861 if $self->{tls}; 2067 if $self->{tls};
1862 2068
2069 unless (defined $AnyEvent::TLS::VERSION) {
2070 eval {
2071 require Net::SSLeay;
2072 require AnyEvent::TLS;
2073 1
2074 } or return $self->_error (Errno::EPROTO, 1, "TLS support not available on this system");
2075 }
2076
1863 $self->{tls} = $tls; 2077 $self->{tls} = $tls;
1864 $self->{tls_ctx} = $ctx if @_ > 2; 2078 $self->{tls_ctx} = $ctx if @_ > 2;
1865 2079
1866 return unless $self->{fh}; 2080 return unless $self->{fh};
1867 2081
1868 require Net::SSLeay;
1869
1870 $ERROR_SYSCALL = Net::SSLeay::ERROR_SYSCALL (); 2082 $ERROR_SYSCALL = Net::SSLeay::ERROR_SYSCALL ();
1871 $ERROR_WANT_READ = Net::SSLeay::ERROR_WANT_READ (); 2083 $ERROR_WANT_READ = Net::SSLeay::ERROR_WANT_READ ();
1872 2084
1873 $tls = delete $self->{tls}; 2085 $tls = delete $self->{tls};
1874 $ctx = $self->{tls_ctx}; 2086 $ctx = $self->{tls_ctx};
1875 2087
1876 local $Carp::CarpLevel = 1; # skip ourselves when creating a new context or session 2088 local $Carp::CarpLevel = 1; # skip ourselves when creating a new context or session
1877 2089
1878 if ("HASH" eq ref $ctx) { 2090 if ("HASH" eq ref $ctx) {
1879 require AnyEvent::TLS;
1880
1881 if ($ctx->{cache}) { 2091 if ($ctx->{cache}) {
1882 my $key = $ctx+0; 2092 my $key = $ctx+0;
1883 $ctx = $TLS_CACHE{$key} ||= new AnyEvent::TLS %$ctx; 2093 $ctx = $TLS_CACHE{$key} ||= new AnyEvent::TLS %$ctx;
1884 } else { 2094 } else {
1885 $ctx = new AnyEvent::TLS %$ctx; 2095 $ctx = new AnyEvent::TLS %$ctx;
… …
1907 Net::SSLeay::CTX_set_mode ($tls, 1|2); 2117 Net::SSLeay::CTX_set_mode ($tls, 1|2);
1908 2118
1909 $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); 2119 $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1910 $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); 2120 $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1911 2121
1912 Net::SSLeay::BIO_write ($self->{_rbio}, delete $self->{rbuf}); 2122 Net::SSLeay::BIO_write ($self->{_rbio}, $self->{rbuf});
2123 $self->{rbuf} = "";
1913 2124
1914 Net::SSLeay::set_bio ($tls, $self->{_rbio}, $self->{_wbio}); 2125 Net::SSLeay::set_bio ($tls, $self->{_rbio}, $self->{_wbio});
1915 2126
1916 $self->{_on_starttls} = sub { $_[0]{on_starttls}(@_) } 2127 $self->{_on_starttls} = sub { $_[0]{on_starttls}(@_) }
1917 if $self->{on_starttls}; 2128 if $self->{on_starttls};
… …
1922 2133
1923=item $handle->stoptls 2134=item $handle->stoptls
1924 2135
1925Shuts down the SSL connection - this makes a proper EOF handshake by 2136Shuts down the SSL connection - this makes a proper EOF handshake by
1926sending a close notify to the other side, but since OpenSSL doesn't 2137sending a close notify to the other side, but since OpenSSL doesn't
1927support non-blocking shut downs, it is not guarenteed that you can re-use 2138support non-blocking shut downs, it is not guaranteed that you can re-use
1928the stream afterwards. 2139the stream afterwards.
2140
2141This method may invoke callbacks (and therefore the handle might be
2142destroyed after it returns).
1929 2143
1930=cut 2144=cut
1931 2145
1932sub stoptls { 2146sub stoptls {
1933 my ($self) = @_; 2147 my ($self) = @_;
1934 2148
1935 if ($self->{tls}) { 2149 if ($self->{tls} && $self->{fh}) {
1936 Net::SSLeay::shutdown ($self->{tls}); 2150 Net::SSLeay::shutdown ($self->{tls});
1937 2151
1938 &_dotls; 2152 &_dotls;
1939 2153
1940# # we don't give a shit. no, we do, but we can't. no...#d# 2154# # we don't give a shit. no, we do, but we can't. no...#d#
… …
1952 if $self->{tls} > 0; 2166 if $self->{tls} > 0;
1953 2167
1954 delete @$self{qw(_rbio _wbio _tls_wbuf _on_starttls)}; 2168 delete @$self{qw(_rbio _wbio _tls_wbuf _on_starttls)};
1955} 2169}
1956 2170
2171=item $handle->resettls
2172
2173This rarely-used method simply resets and TLS state on the handle, usually
2174causing data loss.
2175
2176One case where it may be useful is when you want to skip over the data in
2177the stream but you are not interested in interpreting it, so data loss is
2178no concern.
2179
2180=cut
2181
2182*resettls = \&_freetls;
2183
1957sub DESTROY { 2184sub DESTROY {
1958 my ($self) = @_; 2185 my ($self) = @_;
1959 2186
1960 &_freetls; 2187 &_freetls;
1961 2188
… …
1970 push @linger, AE::io $fh, 1, sub { 2197 push @linger, AE::io $fh, 1, sub {
1971 my $len = syswrite $fh, $wbuf, length $wbuf; 2198 my $len = syswrite $fh, $wbuf, length $wbuf;
1972 2199
1973 if ($len > 0) { 2200 if ($len > 0) {
1974 substr $wbuf, 0, $len, ""; 2201 substr $wbuf, 0, $len, "";
1975 } else { 2202 } elsif (defined $len || ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK)) {
1976 @linger = (); # end 2203 @linger = (); # end
1977 } 2204 }
1978 }; 2205 };
1979 push @linger, AE::timer $linger, 0, sub { 2206 push @linger, AE::timer $linger, 0, sub {
1980 @linger = (); 2207 @linger = ();
… …
2017 2244
2018sub AnyEvent::Handle::destroyed::AUTOLOAD { 2245sub AnyEvent::Handle::destroyed::AUTOLOAD {
2019 #nop 2246 #nop
2020} 2247}
2021 2248
2249=item $handle->destroyed
2250
2251Returns false as long as the handle hasn't been destroyed by a call to C<<
2252->destroy >>, true otherwise.
2253
2254Can be useful to decide whether the handle is still valid after some
2255callback possibly destroyed the handle. For example, C<< ->push_write >>,
2256C<< ->starttls >> and other methods can call user callbacks, which in turn
2257can destroy the handle, so work can be avoided by checking sometimes:
2258
2259 $hdl->starttls ("accept");
2260 return if $hdl->destroyed;
2261 $hdl->push_write (...
2262
2263Note that the call to C<push_write> will silently be ignored if the handle
2264has been destroyed, so often you can just ignore the possibility of the
2265handle being destroyed.
2266
2267=cut
2268
2269sub destroyed { 0 }
2270sub AnyEvent::Handle::destroyed::destroyed { 1 }
2271
2022=item AnyEvent::Handle::TLS_CTX 2272=item AnyEvent::Handle::TLS_CTX
2023 2273
2024This function creates and returns the AnyEvent::TLS object used by default 2274This function creates and returns the AnyEvent::TLS object used by default
2025for TLS mode. 2275for TLS mode.
2026 2276
… …
2053 2303
2054It is only safe to "forget" the reference inside EOF or error callbacks, 2304It is only safe to "forget" the reference inside EOF or error callbacks,
2055from within all other callbacks, you need to explicitly call the C<< 2305from within all other callbacks, you need to explicitly call the C<<
2056->destroy >> method. 2306->destroy >> method.
2057 2307
2308=item Why is my C<on_eof> callback never called?
2309
2310Probably because your C<on_error> callback is being called instead: When
2311you have outstanding requests in your read queue, then an EOF is
2312considered an error as you clearly expected some data.
2313
2314To avoid this, make sure you have an empty read queue whenever your handle
2315is supposed to be "idle" (i.e. connection closes are O.K.). You can set
2316an C<on_read> handler that simply pushes the first read requests in the
2317queue.
2318
2319See also the next question, which explains this in a bit more detail.
2320
2321=item How can I serve requests in a loop?
2322
2323Most protocols consist of some setup phase (authentication for example)
2324followed by a request handling phase, where the server waits for requests
2325and handles them, in a loop.
2326
2327There are two important variants: The first (traditional, better) variant
2328handles requests until the server gets some QUIT command, causing it to
2329close the connection first (highly desirable for a busy TCP server). A
2330client dropping the connection is an error, which means this variant can
2331detect an unexpected detection close.
2332
2333To handle this case, always make sure you have a non-empty read queue, by
2334pushing the "read request start" handler on it:
2335
2336 # we assume a request starts with a single line
2337 my @start_request; @start_request = (line => sub {
2338 my ($hdl, $line) = @_;
2339
2340 ... handle request
2341
2342 # push next request read, possibly from a nested callback
2343 $hdl->push_read (@start_request);
2344 });
2345
2346 # auth done, now go into request handling loop
2347 # now push the first @start_request
2348 $hdl->push_read (@start_request);
2349
2350By always having an outstanding C<push_read>, the handle always expects
2351some data and raises the C<EPIPE> error when the connction is dropped
2352unexpectedly.
2353
2354The second variant is a protocol where the client can drop the connection
2355at any time. For TCP, this means that the server machine may run out of
2356sockets easier, and in general, it means you cannot distinguish a protocl
2357failure/client crash from a normal connection close. Nevertheless, these
2358kinds of protocols are common (and sometimes even the best solution to the
2359problem).
2360
2361Having an outstanding read request at all times is possible if you ignore
2362C<EPIPE> errors, but this doesn't help with when the client drops the
2363connection during a request, which would still be an error.
2364
2365A better solution is to push the initial request read in an C<on_read>
2366callback. This avoids an error, as when the server doesn't expect data
2367(i.e. is idly waiting for the next request, an EOF will not raise an
2368error, but simply result in an C<on_eof> callback. It is also a bit slower
2369and simpler:
2370
2371 # auth done, now go into request handling loop
2372 $hdl->on_read (sub {
2373 my ($hdl) = @_;
2374
2375 # called each time we receive data but the read queue is empty
2376 # simply start read the request
2377
2378 $hdl->push_read (line => sub {
2379 my ($hdl, $line) = @_;
2380
2381 ... handle request
2382
2383 # do nothing special when the request has been handled, just
2384 # let the request queue go empty.
2385 });
2386 });
2387
2058=item I get different callback invocations in TLS mode/Why can't I pause 2388=item I get different callback invocations in TLS mode/Why can't I pause
2059reading? 2389reading?
2060 2390
2061Unlike, say, TCP, TLS connections do not consist of two independent 2391Unlike, say, TCP, TLS connections do not consist of two independent
2062communication channels, one for each direction. Or put differently. The 2392communication channels, one for each direction. Or put differently, the
2063read and write directions are not independent of each other: you cannot 2393read and write directions are not independent of each other: you cannot
2064write data unless you are also prepared to read, and vice versa. 2394write data unless you are also prepared to read, and vice versa.
2065 2395
2066This can mean than, in TLS mode, you might get C<on_error> or C<on_eof> 2396This means that, in TLS mode, you might get C<on_error> or C<on_eof>
2067callback invocations when you are not expecting any read data - the reason 2397callback invocations when you are not expecting any read data - the reason
2068is that AnyEvent::Handle always reads in TLS mode. 2398is that AnyEvent::Handle always reads in TLS mode.
2069 2399
2070During the connection, you have to make sure that you always have a 2400During the connection, you have to make sure that you always have a
2071non-empty read-queue, or an C<on_read> watcher. At the end of the 2401non-empty read-queue, or an C<on_read> watcher. At the end of the
… …
2083 $handle->on_eof (undef); 2413 $handle->on_eof (undef);
2084 $handle->on_error (sub { 2414 $handle->on_error (sub {
2085 my $data = delete $_[0]{rbuf}; 2415 my $data = delete $_[0]{rbuf};
2086 }); 2416 });
2087 2417
2418Note that this example removes the C<rbuf> member from the handle object,
2419which is not normally allowed by the API. It is expressly permitted in
2420this case only, as the handle object needs to be destroyed afterwards.
2421
2088The reason to use C<on_error> is that TCP connections, due to latencies 2422The reason to use C<on_error> is that TCP connections, due to latencies
2089and packets loss, might get closed quite violently with an error, when in 2423and packets loss, might get closed quite violently with an error, when in
2090fact, all data has been received. 2424fact all data has been received.
2091 2425
2092It is usually better to use acknowledgements when transferring data, 2426It is usually better to use acknowledgements when transferring data,
2093to make sure the other side hasn't just died and you got the data 2427to make sure the other side hasn't just died and you got the data
2094intact. This is also one reason why so many internet protocols have an 2428intact. This is also one reason why so many internet protocols have an
2095explicit QUIT command. 2429explicit QUIT command.
… …
2102C<low_water_mark> this will be called precisely when all data has been 2436C<low_water_mark> this will be called precisely when all data has been
2103written to the socket: 2437written to the socket:
2104 2438
2105 $handle->push_write (...); 2439 $handle->push_write (...);
2106 $handle->on_drain (sub { 2440 $handle->on_drain (sub {
2107 warn "all data submitted to the kernel\n"; 2441 AE::log debug => "All data submitted to the kernel.";
2108 undef $handle; 2442 undef $handle;
2109 }); 2443 });
2110 2444
2111If you just want to queue some data and then signal EOF to the other side, 2445If you just want to queue some data and then signal EOF to the other side,
2112consider using C<< ->push_shutdown >> instead. 2446consider using C<< ->push_shutdown >> instead.
2113 2447
2114=item I want to contact a TLS/SSL server, I don't care about security. 2448=item I want to contact a TLS/SSL server, I don't care about security.
2115 2449
2116If your TLS server is a pure TLS server (e.g. HTTPS) that only speaks TLS, 2450If your TLS server is a pure TLS server (e.g. HTTPS) that only speaks TLS,
2117simply connect to it and then create the AnyEvent::Handle with the C<tls> 2451connect to it and then create the AnyEvent::Handle with the C<tls>
2118parameter: 2452parameter:
2119 2453
2120 tcp_connect $host, $port, sub { 2454 tcp_connect $host, $port, sub {
2121 my ($fh) = @_; 2455 my ($fh) = @_;
2122 2456
… …
2196When you have intermediate CA certificates that your clients might not 2530When you have intermediate CA certificates that your clients might not
2197know about, just append them to the C<cert_file>. 2531know about, just append them to the C<cert_file>.
2198 2532
2199=back 2533=back
2200 2534
2201
2202=head1 SUBCLASSING AnyEvent::Handle 2535=head1 SUBCLASSING AnyEvent::Handle
2203 2536
2204In many cases, you might want to subclass AnyEvent::Handle. 2537In many cases, you might want to subclass AnyEvent::Handle.
2205 2538
2206To make this easier, a given version of AnyEvent::Handle uses these 2539To make this easier, a given version of AnyEvent::Handle uses these
… …
2222 2555
2223=item * all members not documented here and not prefixed with an underscore 2556=item * all members not documented here and not prefixed with an underscore
2224are free to use in subclasses. 2557are free to use in subclasses.
2225 2558
2226Of course, new versions of AnyEvent::Handle may introduce more "public" 2559Of course, new versions of AnyEvent::Handle may introduce more "public"
2227member variables, but thats just life, at least it is documented. 2560member variables, but that's just life. At least it is documented.
2228 2561
2229=back 2562=back
2230 2563
2231=head1 AUTHOR 2564=head1 AUTHOR
2232 2565
2233Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>. 2566Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>.
2234 2567
2235=cut 2568=cut
2236 2569
22371; # End of AnyEvent::Handle 25701
2571

Diff Legend

– Removed lines
+ Added lines
< Changed lines
> Changed lines