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Revision 1.183 by root, Thu Sep 3 12:45:35 2009 UTC vs.
Revision 1.214 by root, Sun Jan 16 17:12:27 2011 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;
… …
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 warn "got error $msg\n";
17 $hdl->destroy; 17 $hdl->destroy;
18 $cv->send; 18 $cv->send;
19 ); 19 };
20 20
21 # send some request line 21 # send some request line
22 $hdl->push_write ("getinfo\015\012"); 22 $hdl->push_write ("getinfo\015\012");
23 23
24 # read the response line 24 # read the response line
… …
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, $retry->())
112 129
113This callback is called when a connection has been successfully established. 130This callback is called when a connection has been successfully established.
114 131
115The actual numeric host and port (the socket peername) are passed as 132The peer's numeric host and port (the socket peername) are passed as
116parameters, together with a retry callback. 133parameters, together with a retry callback.
117 134
118When, for some reason, the handle is not acceptable, then calling 135If, for some reason, the handle is not acceptable, calling C<$retry>
119C<$retry> will continue with the next conenction target (in case of 136will continue with the next connection target (in case of multi-homed
120multi-homed hosts or SRV records there can be multiple connection 137hosts or SRV records there can be multiple connection endpoints). At the
121endpoints). When it is called then the read and write queues, eof status, 138time it is called the read and write queues, eof status, tls status and
122tls status and similar properties of the handle are being reset. 139similar properties of the handle will have been reset.
123 140
124In most cases, ignoring the C<$retry> parameter is the way to go. 141In most cases, you should ignore the C<$retry> parameter.
125 142
126=item on_connect_error => $cb->($handle, $message) 143=item on_connect_error => $cb->($handle, $message)
127 144
128This callback is called when the conenction could not be 145This callback is called when the connection could not be
129established. C<$!> will contain the relevant error code, and C<$message> a 146established. C<$!> will contain the relevant error code, and C<$message> a
130message describing it (usually the same as C<"$!">). 147message describing it (usually the same as C<"$!">).
131 148
132If this callback isn't specified, then C<on_error> will be called with a 149If this callback isn't specified, then C<on_error> will be called with a
133fatal error instead. 150fatal error instead.
… …
136 153
137=item on_error => $cb->($handle, $fatal, $message) 154=item on_error => $cb->($handle, $fatal, $message)
138 155
139This is the error callback, which is called when, well, some error 156This is the error callback, which is called when, well, some error
140occured, such as not being able to resolve the hostname, failure to 157occured, such as not being able to resolve the hostname, failure to
141connect or a read error. 158connect, or a read error.
142 159
143Some errors are fatal (which is indicated by C<$fatal> being true). On 160Some errors are fatal (which is indicated by C<$fatal> being true). On
144fatal errors the handle object will be destroyed (by a call to C<< -> 161fatal errors the handle object will be destroyed (by a call to C<< ->
145destroy >>) after invoking the error callback (which means you are free to 162destroy >>) after invoking the error callback (which means you are free to
146examine the handle object). Examples of fatal errors are an EOF condition 163examine the handle object). Examples of fatal errors are an EOF condition
147with active (but unsatisifable) read watchers (C<EPIPE>) or I/O errors. In 164with active (but unsatisfiable) read watchers (C<EPIPE>) or I/O errors. In
148cases where the other side can close the connection at their will it is 165cases where the other side can close the connection at will, it is
149often easiest to not report C<EPIPE> errors in this callback. 166often easiest to not report C<EPIPE> errors in this callback.
150 167
151AnyEvent::Handle tries to find an appropriate error code for you to check 168AnyEvent::Handle tries to find an appropriate error code for you to check
152against, but in some cases (TLS errors), this does not work well. It is 169against, but in some cases (TLS errors), this does not work well. It is
153recommended to always output the C<$message> argument in human-readable 170recommended to always output the C<$message> argument in human-readable
154error messages (it's usually the same as C<"$!">). 171error messages (it's usually the same as C<"$!">).
155 172
156Non-fatal errors can be retried by simply returning, but it is recommended 173Non-fatal errors can be retried by returning, but it is recommended
157to simply ignore this parameter and instead abondon the handle object 174to simply ignore this parameter and instead abondon the handle object
158when this callback is invoked. Examples of non-fatal errors are timeouts 175when this callback is invoked. Examples of non-fatal errors are timeouts
159C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>). 176C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>).
160 177
161On callback entrance, the value of C<$!> contains the operating system 178On entry to the callback, the value of C<$!> contains the operating
162error code (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT>, C<EBADMSG> or 179system error code (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT>, C<EBADMSG> or
163C<EPROTO>). 180C<EPROTO>).
164 181
165While not mandatory, it is I<highly> recommended to set this callback, as 182While not mandatory, it is I<highly> recommended to set this callback, as
166you will not be notified of errors otherwise. The default simply calls 183you will not be notified of errors otherwise. The default just calls
167C<croak>. 184C<croak>.
168 185
169=item on_read => $cb->($handle) 186=item on_read => $cb->($handle)
170 187
171This sets the default read callback, which is called when data arrives 188This sets the default read callback, which is called when data arrives
… …
176To access (and remove data from) the read buffer, use the C<< ->rbuf >> 193To access (and remove data from) the read buffer, use the C<< ->rbuf >>
177method or access the C<< $handle->{rbuf} >> member directly. Note that you 194method or access the C<< $handle->{rbuf} >> member directly. Note that you
178must not enlarge or modify the read buffer, you can only remove data at 195must not enlarge or modify the read buffer, you can only remove data at
179the beginning from it. 196the beginning from it.
180 197
198You can also call C<< ->push_read (...) >> or any other function that
199modifies the read queue. Or do both. Or ...
200
181When an EOF condition is detected then AnyEvent::Handle will first try to 201When an EOF condition is detected, AnyEvent::Handle will first try to
182feed all the remaining data to the queued callbacks and C<on_read> before 202feed all the remaining data to the queued callbacks and C<on_read> before
183calling the C<on_eof> callback. If no progress can be made, then a fatal 203calling the C<on_eof> callback. If no progress can be made, then a fatal
184error will be raised (with C<$!> set to C<EPIPE>). 204error will be raised (with C<$!> set to C<EPIPE>).
185 205
186Note that, unlike requests in the read queue, an C<on_read> callback 206Note that, unlike requests in the read queue, an C<on_read> callback
… …
205set, then a fatal error will be raised with C<$!> set to <0>. 225set, then a fatal error will be raised with C<$!> set to <0>.
206 226
207=item on_drain => $cb->($handle) 227=item on_drain => $cb->($handle)
208 228
209This sets the callback that is called when the write buffer becomes empty 229This sets the callback that is called when the write buffer becomes empty
210(or when the callback is set and the buffer is empty already). 230(or immediately if the buffer is empty already).
211 231
212To append to the write buffer, use the C<< ->push_write >> method. 232To append to the write buffer, use the C<< ->push_write >> method.
213 233
214This callback is useful when you don't want to put all of your write data 234This 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 235into 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 247many 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 248file 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> 249will be invoked (and if that one is missing, a non-fatal C<ETIMEDOUT>
230error will be raised). 250error will be raised).
231 251
232There are three variants of the timeouts that work fully independent 252There are three variants of the timeouts that work independently
233of each other, for both read and write, just read, and just write: 253of each other, for both read and write, just read, and just write:
234C<timeout>, C<rtimeout> and C<wtimeout>, with corresponding callbacks 254C<timeout>, C<rtimeout> and C<wtimeout>, with corresponding callbacks
235C<on_timeout>, C<on_rtimeout> and C<on_wtimeout>, and reset functions 255C<on_timeout>, C<on_rtimeout> and C<on_wtimeout>, and reset functions
236C<timeout_reset>, C<rtimeout_reset>, and C<wtimeout_reset>. 256C<timeout_reset>, C<rtimeout_reset>, and C<wtimeout_reset>.
237 257
238Note that timeout processing is also active when you currently do not have 258Note that timeout processing is active even when you do not have
239any outstanding read or write requests: If you plan to keep the connection 259any outstanding read or write requests: If you plan to keep the connection
240idle then you should disable the timout temporarily or ignore the timeout 260idle then you should disable the timeout temporarily or ignore the timeout
241in the C<on_timeout> callback, in which case AnyEvent::Handle will simply 261in the C<on_timeout> callback, in which case AnyEvent::Handle will simply
242restart the timeout. 262restart the timeout.
243 263
244Zero (the default) disables this timeout. 264Zero (the default) disables this timeout.
245 265
… …
259be configured to accept only so-and-so much data that it cannot act on 279be 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 280(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 281amount of data without a callback ever being called as long as the line
262isn't finished). 282isn't finished).
263 283
284=item wbuf_max => <bytes>
285
286If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)
287when the write buffer ever (strictly) exceeds this size. This is useful to
288avoid some forms of denial-of-service attacks.
289
290Although the units of this parameter is bytes, this is the I<raw> number
291of bytes not yet accepted by the kernel. This can make a difference when
292you e.g. use TLS, as TLS typically makes your write data larger (but it
293can also make it smaller due to compression).
294
295As an example of when this limit is useful, take a chat server that sends
296chat messages to a client. If the client does not read those in a timely
297manner then the send buffer in the server would grow unbounded.
298
264=item autocork => <boolean> 299=item autocork => <boolean>
265 300
266When disabled (the default), then C<push_write> will try to immediately 301When disabled (the default), C<push_write> will try to immediately
267write the data to the handle, if possible. This avoids having to register 302write 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 303a write watcher and wait for the next event loop iteration, but can
269be inefficient if you write multiple small chunks (on the wire, this 304be inefficient if you write multiple small chunks (on the wire, this
270disadvantage is usually avoided by your kernel's nagle algorithm, see 305disadvantage is usually avoided by your kernel's nagle algorithm, see
271C<no_delay>, but this option can save costly syscalls). 306C<no_delay>, but this option can save costly syscalls).
272 307
273When enabled, then writes will always be queued till the next event loop 308When enabled, writes will always be queued till the next event loop
274iteration. This is efficient when you do many small writes per iteration, 309iteration. 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 310but less efficient when you do a single write only per iteration (or when
276the write buffer often is full). It also increases write latency. 311the write buffer often is full). It also increases write latency.
277 312
278=item no_delay => <boolean> 313=item no_delay => <boolean>
… …
282the Nagle algorithm, and usually it is beneficial. 317the Nagle algorithm, and usually it is beneficial.
283 318
284In some situations you want as low a delay as possible, which can be 319In some situations you want as low a delay as possible, which can be
285accomplishd by setting this option to a true value. 320accomplishd by setting this option to a true value.
286 321
287The default is your opertaing system's default behaviour (most likely 322The default is your operating system's default behaviour (most likely
288enabled), this option explicitly enables or disables it, if possible. 323enabled). This option explicitly enables or disables it, if possible.
289 324
290=item keepalive => <boolean> 325=item keepalive => <boolean>
291 326
292Enables (default disable) the SO_KEEPALIVE option on the stream socket: 327Enables (default disable) the SO_KEEPALIVE option on the stream socket:
293normally, TCP connections have no time-out once established, so TCP 328normally, TCP connections have no time-out once established, so TCP
294conenctions, once established, can stay alive forever even when the other 329connections, 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 330side 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 331TCP connections when the other side becomes unreachable. While the default
297is OS-dependent, TCP keepalives usually kick in after around two hours, 332is 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 333and, if the other side doesn't reply, take down the TCP connection some 10
299to 15 minutes later. 334to 15 minutes later.
300 335
301It is harmless to specify this option for file handles that do not support 336It is harmless to specify this option for file handles that do not support
… …
312is enabled) gives you the most portable way of getting urgent data, by 347is enabled) gives you the most portable way of getting urgent data, by
313putting it into the stream. 348putting it into the stream.
314 349
315Since BSD emulation of OOB data on top of TCP's urgent data can have 350Since BSD emulation of OOB data on top of TCP's urgent data can have
316security implications, AnyEvent::Handle sets this flag automatically 351security implications, AnyEvent::Handle sets this flag automatically
317unless explicitly specified. 352unless explicitly specified. Note that setting this flag after
353establishing a connection I<may> be a bit too late (data loss could
354already have occured on BSD systems), but at least it will protect you
355from most attacks.
318 356
319=item read_size => <bytes> 357=item read_size => <bytes>
320 358
321The default read block size (the amount of bytes this module will 359The initial read block size, the number of bytes this module will try to
322try to read during each loop iteration, which affects memory 360read during each loop iteration. Each handle object will consume at least
323requirements). Default: C<8192>. 361this amount of memory for the read buffer as well, so when handling many
362connections requirements). See also C<max_read_size>. Default: C<2048>.
363
364=item max_read_size => <bytes>
365
366The maximum read buffer size used by the dynamic adjustment
367algorithm: Each time AnyEvent::Handle can read C<read_size> bytes in
368one go it will double C<read_size> up to the maximum given by this
369option. Default: C<131072> or C<read_size>, whichever is higher.
324 370
325=item low_water_mark => <bytes> 371=item low_water_mark => <bytes>
326 372
327Sets the amount of bytes (default: C<0>) that make up an "empty" write 373Sets the number of bytes (default: C<0>) that make up an "empty" write
328buffer: If the write reaches this size or gets even samller it is 374buffer: If the buffer reaches this size or gets even samller it is
329considered empty. 375considered empty.
330 376
331Sometimes it can be beneficial (for performance reasons) to add data to 377Sometimes it can be beneficial (for performance reasons) to add data to
332the write buffer before it is fully drained, but this is a rare case, as 378the write buffer before it is fully drained, but this is a rare case, as
333the operating system kernel usually buffers data as well, so the default 379the operating system kernel usually buffers data as well, so the default
334is good in almost all cases. 380is good in almost all cases.
335 381
336=item linger => <seconds> 382=item linger => <seconds>
337 383
338If non-zero (default: C<3600>), then the destructor of the 384If this is non-zero (default: C<3600>), the destructor of the
339AnyEvent::Handle object will check whether there is still outstanding 385AnyEvent::Handle object will check whether there is still outstanding
340write data and will install a watcher that will write this data to the 386write data and will install a watcher that will write this data to the
341socket. No errors will be reported (this mostly matches how the operating 387socket. No errors will be reported (this mostly matches how the operating
342system treats outstanding data at socket close time). 388system treats outstanding data at socket close time).
343 389
… …
350A string used to identify the remote site - usually the DNS hostname 396A string used to identify the remote site - usually the DNS hostname
351(I<not> IDN!) used to create the connection, rarely the IP address. 397(I<not> IDN!) used to create the connection, rarely the IP address.
352 398
353Apart from being useful in error messages, this string is also used in TLS 399Apart from being useful in error messages, this string is also used in TLS
354peername verification (see C<verify_peername> in L<AnyEvent::TLS>). This 400peername verification (see C<verify_peername> in L<AnyEvent::TLS>). This
355verification will be skipped when C<peername> is not specified or 401verification will be skipped when C<peername> is not specified or is
356C<undef>. 402C<undef>.
357 403
358=item tls => "accept" | "connect" | Net::SSLeay::SSL object 404=item tls => "accept" | "connect" | Net::SSLeay::SSL object
359 405
360When this parameter is given, it enables TLS (SSL) mode, that means 406When this parameter is given, it enables TLS (SSL) mode, that means
361AnyEvent will start a TLS handshake as soon as the conenction has been 407AnyEvent will start a TLS handshake as soon as the connection has been
362established and will transparently encrypt/decrypt data afterwards. 408established and will transparently encrypt/decrypt data afterwards.
363 409
364All TLS protocol errors will be signalled as C<EPROTO>, with an 410All TLS protocol errors will be signalled as C<EPROTO>, with an
365appropriate error message. 411appropriate error message.
366 412
… …
386B<IMPORTANT:> since Net::SSLeay "objects" are really only integers, 432B<IMPORTANT:> since Net::SSLeay "objects" are really only integers,
387passing in the wrong integer will lead to certain crash. This most often 433passing in the wrong integer will lead to certain crash. This most often
388happens when one uses a stylish C<< tls => 1 >> and is surprised about the 434happens when one uses a stylish C<< tls => 1 >> and is surprised about the
389segmentation fault. 435segmentation fault.
390 436
391See the C<< ->starttls >> method for when need to start TLS negotiation later. 437Use the C<< ->starttls >> method if you need to start TLS negotiation later.
392 438
393=item tls_ctx => $anyevent_tls 439=item tls_ctx => $anyevent_tls
394 440
395Use the given C<AnyEvent::TLS> object to create the new TLS connection 441Use the given C<AnyEvent::TLS> object to create the new TLS connection
396(unless a connection object was specified directly). If this parameter is 442(unless a connection object was specified directly). If this
397missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>. 443parameter is missing (or C<undef>), then AnyEvent::Handle will use
444C<AnyEvent::Handle::TLS_CTX>.
398 445
399Instead of an object, you can also specify a hash reference with C<< key 446Instead of an object, you can also specify a hash reference with C<< key
400=> value >> pairs. Those will be passed to L<AnyEvent::TLS> to create a 447=> value >> pairs. Those will be passed to L<AnyEvent::TLS> to create a
401new TLS context object. 448new TLS context object.
402 449
… …
411 458
412TLS handshake failures will not cause C<on_error> to be invoked when this 459TLS handshake failures will not cause C<on_error> to be invoked when this
413callback is in effect, instead, the error message will be passed to C<on_starttls>. 460callback is in effect, instead, the error message will be passed to C<on_starttls>.
414 461
415Without this callback, handshake failures lead to C<on_error> being 462Without this callback, handshake failures lead to C<on_error> being
416called, as normal. 463called as usual.
417 464
418Note that you cannot call C<starttls> right again in this callback. If you 465Note that you cannot just call C<starttls> again in this callback. If you
419need to do that, start an zero-second timer instead whose callback can 466need to do that, start an zero-second timer instead whose callback can
420then call C<< ->starttls >> again. 467then call C<< ->starttls >> again.
421 468
422=item on_stoptls => $cb->($handle) 469=item on_stoptls => $cb->($handle)
423 470
… …
470 AnyEvent::Socket::tcp_connect ( 517 AnyEvent::Socket::tcp_connect (
471 $self->{connect}[0], 518 $self->{connect}[0],
472 $self->{connect}[1], 519 $self->{connect}[1],
473 sub { 520 sub {
474 my ($fh, $host, $port, $retry) = @_; 521 my ($fh, $host, $port, $retry) = @_;
522
523 delete $self->{_connect}; # no longer needed
475 524
476 if ($fh) { 525 if ($fh) {
477 $self->{fh} = $fh; 526 $self->{fh} = $fh;
478 527
479 delete $self->{_skip_drain_rbuf}; 528 delete $self->{_skip_drain_rbuf};
… …
497 }, 546 },
498 sub { 547 sub {
499 local $self->{fh} = $_[0]; 548 local $self->{fh} = $_[0];
500 549
501 $self->{on_prepare} 550 $self->{on_prepare}
502 ? $self->{on_prepare}->($self) 551 ? $self->{on_prepare}->($self)
503 : () 552 : ()
504 } 553 }
505 ); 554 );
506 } 555 }
507 556
… …
513} 562}
514 563
515sub _start { 564sub _start {
516 my ($self) = @_; 565 my ($self) = @_;
517 566
567 # too many clueless people try to use udp and similar sockets
568 # with AnyEvent::Handle, do them a favour.
569 my $type = getsockopt $self->{fh}, Socket::SOL_SOCKET (), Socket::SO_TYPE ();
570 Carp::croak "AnyEvent::Handle: only stream sockets supported, anything else will NOT work!"
571 if Socket::SOCK_STREAM () != (unpack "I", $type) && defined $type;
572
518 AnyEvent::Util::fh_nonblocking $self->{fh}, 1; 573 AnyEvent::Util::fh_nonblocking $self->{fh}, 1;
519 574
520 $self->{_activity} = 575 $self->{_activity} =
521 $self->{_ractivity} = 576 $self->{_ractivity} =
522 $self->{_wactivity} = AE::now; 577 $self->{_wactivity} = AE::now;
523 578
579 $self->{read_size} ||= 2048;
580 $self->{max_read_size} = $self->{read_size}
581 if $self->{read_size} > ($self->{max_read_size} || MAX_READ_SIZE);
582
524 $self->timeout (delete $self->{timeout} ) if $self->{timeout}; 583 $self->timeout (delete $self->{timeout} ) if $self->{timeout};
525 $self->rtimeout (delete $self->{rtimeout} ) if $self->{rtimeout}; 584 $self->rtimeout (delete $self->{rtimeout} ) if $self->{rtimeout};
526 $self->wtimeout (delete $self->{wtimeout} ) if $self->{wtimeout}; 585 $self->wtimeout (delete $self->{wtimeout} ) if $self->{wtimeout};
527 586
528 $self->no_delay (delete $self->{no_delay} ) if exists $self->{no_delay} && $self->{no_delay}; 587 $self->no_delay (delete $self->{no_delay} ) if exists $self->{no_delay} && $self->{no_delay};
… …
531 $self->oobinline (exists $self->{oobinline} ? delete $self->{oobinline} : 1); 590 $self->oobinline (exists $self->{oobinline} ? delete $self->{oobinline} : 1);
532 591
533 $self->starttls (delete $self->{tls}, delete $self->{tls_ctx}) 592 $self->starttls (delete $self->{tls}, delete $self->{tls_ctx})
534 if $self->{tls}; 593 if $self->{tls};
535 594
536 $self->on_drain (delete $self->{on_drain}) if $self->{on_drain}; 595 $self->on_drain (delete $self->{on_drain} ) if $self->{on_drain};
537 596
538 $self->start_read 597 $self->start_read
539 if $self->{on_read} || @{ $self->{_queue} }; 598 if $self->{on_read} || @{ $self->{_queue} };
540 599
541 $self->_drain_wbuf; 600 $self->_drain_wbuf;
… …
548 $message ||= "$!"; 607 $message ||= "$!";
549 608
550 if ($self->{on_error}) { 609 if ($self->{on_error}) {
551 $self->{on_error}($self, $fatal, $message); 610 $self->{on_error}($self, $fatal, $message);
552 $self->destroy if $fatal; 611 $self->destroy if $fatal;
553 } elsif ($self->{fh}) { 612 } elsif ($self->{fh} || $self->{connect}) {
554 $self->destroy; 613 $self->destroy;
555 Carp::croak "AnyEvent::Handle uncaught error: $message"; 614 Carp::croak "AnyEvent::Handle uncaught error: $message";
556 } 615 }
557} 616}
558 617
… …
617=cut 676=cut
618 677
619sub no_delay { 678sub no_delay {
620 $_[0]{no_delay} = $_[1]; 679 $_[0]{no_delay} = $_[1];
621 680
622 eval {
623 local $SIG{__DIE__};
624 setsockopt $_[0]{fh}, Socket::IPPROTO_TCP (), Socket::TCP_NODELAY (), int $_[1] 681 setsockopt $_[0]{fh}, Socket::IPPROTO_TCP (), Socket::TCP_NODELAY (), int $_[1]
625 if $_[0]{fh}; 682 if $_[0]{fh};
626 };
627} 683}
628 684
629=item $handle->keepalive ($boolean) 685=item $handle->keepalive ($boolean)
630 686
631Enables or disables the C<keepalive> setting (see constructor argument of 687Enables or disables the C<keepalive> setting (see constructor argument of
… …
691 747
692Replace the current C<on_stoptls> callback (see the C<on_stoptls> constructor argument). 748Replace the current C<on_stoptls> callback (see the C<on_stoptls> constructor argument).
693 749
694=cut 750=cut
695 751
696sub on_starttls { 752sub on_stoptls {
697 $_[0]{on_stoptls} = $_[1]; 753 $_[0]{on_stoptls} = $_[1];
698} 754}
699 755
700=item $handle->rbuf_max ($max_octets) 756=item $handle->rbuf_max ($max_octets)
701 757
702Configures the C<rbuf_max> setting (C<undef> disables it). 758Configures the C<rbuf_max> setting (C<undef> disables it).
759
760=item $handle->wbuf_max ($max_octets)
761
762Configures the C<wbuf_max> setting (C<undef> disables it).
703 763
704=cut 764=cut
705 765
706sub rbuf_max { 766sub rbuf_max {
707 $_[0]{rbuf_max} = $_[1]; 767 $_[0]{rbuf_max} = $_[1];
768}
769
770sub rbuf_max {
771 $_[0]{wbuf_max} = $_[1];
708} 772}
709 773
710############################################################################# 774#############################################################################
711 775
712=item $handle->timeout ($seconds) 776=item $handle->timeout ($seconds)
… …
740 $_[0]{$on_timeout} = $_[1]; 804 $_[0]{$on_timeout} = $_[1];
741 }; 805 };
742 806
743 *$timeout = sub { 807 *$timeout = sub {
744 my ($self, $new_value) = @_; 808 my ($self, $new_value) = @_;
809
810 $new_value >= 0
811 or Carp::croak "AnyEvent::Handle->$timeout called with negative timeout ($new_value), caught";
745 812
746 $self->{$timeout} = $new_value; 813 $self->{$timeout} = $new_value;
747 delete $self->{$tw}; &$cb; 814 delete $self->{$tw}; &$cb;
748 }; 815 };
749 816
… …
813=item $handle->on_drain ($cb) 880=item $handle->on_drain ($cb)
814 881
815Sets the C<on_drain> callback or clears it (see the description of 882Sets the C<on_drain> callback or clears it (see the description of
816C<on_drain> in the constructor). 883C<on_drain> in the constructor).
817 884
885This method may invoke callbacks (and therefore the handle might be
886destroyed after it returns).
887
818=cut 888=cut
819 889
820sub on_drain { 890sub on_drain {
821 my ($self, $cb) = @_; 891 my ($self, $cb) = @_;
822 892
… …
826 if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf}); 896 if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf});
827} 897}
828 898
829=item $handle->push_write ($data) 899=item $handle->push_write ($data)
830 900
831Queues the given scalar to be written. You can push as much data as you 901Queues the given scalar to be written. You can push as much data as
832want (only limited by the available memory), as C<AnyEvent::Handle> 902you want (only limited by the available memory and C<wbuf_max>), as
833buffers it independently of the kernel. 903C<AnyEvent::Handle> buffers it independently of the kernel.
904
905This method may invoke callbacks (and therefore the handle might be
906destroyed after it returns).
834 907
835=cut 908=cut
836 909
837sub _drain_wbuf { 910sub _drain_wbuf {
838 my ($self) = @_; 911 my ($self) = @_;
… …
863 $cb->() unless $self->{autocork}; 936 $cb->() unless $self->{autocork};
864 937
865 # if still data left in wbuf, we need to poll 938 # if still data left in wbuf, we need to poll
866 $self->{_ww} = AE::io $self->{fh}, 1, $cb 939 $self->{_ww} = AE::io $self->{fh}, 1, $cb
867 if length $self->{wbuf}; 940 if length $self->{wbuf};
941
942 if (
943 defined $self->{wbuf_max}
944 && $self->{wbuf_max} < length $self->{wbuf}
945 ) {
946 $self->_error (Errno::ENOSPC, 1), return;
947 }
868 }; 948 };
869} 949}
870 950
871our %WH; 951our %WH;
872 952
953# deprecated
873sub register_write_type($$) { 954sub register_write_type($$) {
874 $WH{$_[0]} = $_[1]; 955 $WH{$_[0]} = $_[1];
875} 956}
876 957
877sub push_write { 958sub push_write {
878 my $self = shift; 959 my $self = shift;
879 960
880 if (@_ > 1) { 961 if (@_ > 1) {
881 my $type = shift; 962 my $type = shift;
882 963
964 @_ = ($WH{$type} ||= _load_func "$type\::anyevent_write_type"
883 @_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write") 965 or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::push_write")
884 ->($self, @_); 966 ->($self, @_);
885 } 967 }
886 968
969 # we downgrade here to avoid hard-to-track-down bugs,
970 # and diagnose the problem earlier and better.
971
887 if ($self->{tls}) { 972 if ($self->{tls}) {
888 $self->{_tls_wbuf} .= $_[0]; 973 utf8::downgrade $self->{_tls_wbuf} .= $_[0];
889 &_dotls ($self) if $self->{fh}; 974 &_dotls ($self) if $self->{fh};
890 } else { 975 } else {
891 $self->{wbuf} .= $_[0]; 976 utf8::downgrade $self->{wbuf} .= $_[0];
892 $self->_drain_wbuf if $self->{fh}; 977 $self->_drain_wbuf if $self->{fh};
893 } 978 }
894} 979}
895 980
896=item $handle->push_write (type => @args) 981=item $handle->push_write (type => @args)
897 982
898Instead of formatting your data yourself, you can also let this module do 983Instead of formatting your data yourself, you can also let this module
899the job by specifying a type and type-specific arguments. 984do the job by specifying a type and type-specific arguments. You
985can also specify the (fully qualified) name of a package, in which
986case AnyEvent tries to load the package and then expects to find the
987C<anyevent_write_type> function inside (see "custom write types", below).
900 988
901Predefined types are (if you have ideas for additional types, feel free to 989Predefined types are (if you have ideas for additional types, feel free to
902drop by and tell us): 990drop by and tell us):
903 991
904=over 4 992=over 4
… …
999before it was actually written. One way to do that is to replace your 1087before it was actually written. One way to do that is to replace your
1000C<on_drain> handler by a callback that shuts down the socket (and set 1088C<on_drain> handler by a callback that shuts down the socket (and set
1001C<low_water_mark> to C<0>). This method is a shorthand for just that, and 1089C<low_water_mark> to C<0>). This method is a shorthand for just that, and
1002replaces the C<on_drain> callback with: 1090replaces the C<on_drain> callback with:
1003 1091
1004 sub { shutdown $_[0]{fh}, 1 } # for push_shutdown 1092 sub { shutdown $_[0]{fh}, 1 }
1005 1093
1006This simply shuts down the write side and signals an EOF condition to the 1094This simply shuts down the write side and signals an EOF condition to the
1007the peer. 1095the peer.
1008 1096
1009You can rely on the normal read queue and C<on_eof> handling 1097You can rely on the normal read queue and C<on_eof> handling
1010afterwards. This is the cleanest way to close a connection. 1098afterwards. This is the cleanest way to close a connection.
1011 1099
1100This method may invoke callbacks (and therefore the handle might be
1101destroyed after it returns).
1102
1012=cut 1103=cut
1013 1104
1014sub push_shutdown { 1105sub push_shutdown {
1015 my ($self) = @_; 1106 my ($self) = @_;
1016 1107
1017 delete $self->{low_water_mark}; 1108 delete $self->{low_water_mark};
1018 $self->on_drain (sub { shutdown $_[0]{fh}, 1 }); 1109 $self->on_drain (sub { shutdown $_[0]{fh}, 1 });
1019} 1110}
1020 1111
1021=item AnyEvent::Handle::register_write_type type => $coderef->($handle, @args) 1112=item custom write types - Package::anyevent_write_type $handle, @args
1022 1113
1023This function (not method) lets you add your own types to C<push_write>. 1114Instead of one of the predefined types, you can also specify the name of
1115a package. AnyEvent will try to load the package and then expects to find
1116a function named C<anyevent_write_type> inside. If it isn't found, it
1117progressively tries to load the parent package until it either finds the
1118function (good) or runs out of packages (bad).
1119
1024Whenever the given C<type> is used, C<push_write> will invoke the code 1120Whenever the given C<type> is used, C<push_write> will the function with
1025reference with the handle object and the remaining arguments. 1121the handle object and the remaining arguments.
1026 1122
1027The code reference is supposed to return a single octet string that will 1123The function is supposed to return a single octet string that will be
1028be appended to the write buffer. 1124appended to the write buffer, so you cna mentally treat this function as a
1125"arguments to on-the-wire-format" converter.
1029 1126
1030Note that this is a function, and all types registered this way will be 1127Example: implement a custom write type C<join> that joins the remaining
1031global, so try to use unique names. 1128arguments using the first one.
1129
1130 $handle->push_write (My::Type => " ", 1,2,3);
1131
1132 # uses the following package, which can be defined in the "My::Type" or in
1133 # the "My" modules to be auto-loaded, or just about anywhere when the
1134 # My::Type::anyevent_write_type is defined before invoking it.
1135
1136 package My::Type;
1137
1138 sub anyevent_write_type {
1139 my ($handle, $delim, @args) = @_;
1140
1141 join $delim, @args
1142 }
1032 1143
1033=cut 1144=cut
1034 1145
1035############################################################################# 1146#############################################################################
1036 1147
… …
1045ways, the "simple" way, using only C<on_read> and the "complex" way, using 1156ways, the "simple" way, using only C<on_read> and the "complex" way, using
1046a queue. 1157a queue.
1047 1158
1048In the simple case, you just install an C<on_read> callback and whenever 1159In the simple case, you just install an C<on_read> callback and whenever
1049new data arrives, it will be called. You can then remove some data (if 1160new data arrives, it will be called. You can then remove some data (if
1050enough is there) from the read buffer (C<< $handle->rbuf >>). Or you cna 1161enough is there) from the read buffer (C<< $handle->rbuf >>). Or you can
1051leave the data there if you want to accumulate more (e.g. when only a 1162leave the data there if you want to accumulate more (e.g. when only a
1052partial message has been received so far). 1163partial message has been received so far), or change the read queue with
1164e.g. C<push_read>.
1053 1165
1054In the more complex case, you want to queue multiple callbacks. In this 1166In the more complex case, you want to queue multiple callbacks. In this
1055case, AnyEvent::Handle will call the first queued callback each time new 1167case, AnyEvent::Handle will call the first queued callback each time new
1056data arrives (also the first time it is queued) and removes it when it has 1168data arrives (also the first time it is queued) and remove it when it has
1057done its job (see C<push_read>, below). 1169done its job (see C<push_read>, below).
1058 1170
1059This way you can, for example, push three line-reads, followed by reading 1171This way you can, for example, push three line-reads, followed by reading
1060a chunk of data, and AnyEvent::Handle will execute them in order. 1172a chunk of data, and AnyEvent::Handle will execute them in order.
1061 1173
… …
1192 1304
1193This replaces the currently set C<on_read> callback, or clears it (when 1305This replaces the currently set C<on_read> callback, or clears it (when
1194the new callback is C<undef>). See the description of C<on_read> in the 1306the new callback is C<undef>). See the description of C<on_read> in the
1195constructor. 1307constructor.
1196 1308
1309This method may invoke callbacks (and therefore the handle might be
1310destroyed after it returns).
1311
1197=cut 1312=cut
1198 1313
1199sub on_read { 1314sub on_read {
1200 my ($self, $cb) = @_; 1315 my ($self, $cb) = @_;
1201 1316
… …
1203 $self->_drain_rbuf if $cb; 1318 $self->_drain_rbuf if $cb;
1204} 1319}
1205 1320
1206=item $handle->rbuf 1321=item $handle->rbuf
1207 1322
1208Returns the read buffer (as a modifiable lvalue). 1323Returns the read buffer (as a modifiable lvalue). You can also access the
1324read buffer directly as the C<< ->{rbuf} >> member, if you want (this is
1325much faster, and no less clean).
1209 1326
1210You can access the read buffer directly as the C<< ->{rbuf} >> 1327The only operation allowed on the read buffer (apart from looking at it)
1211member, if you want. However, the only operation allowed on the 1328is removing data from its beginning. Otherwise modifying or appending to
1212read buffer (apart from looking at it) is removing data from its 1329it is not allowed and will lead to hard-to-track-down bugs.
1213beginning. Otherwise modifying or appending to it is not allowed and will
1214lead to hard-to-track-down bugs.
1215 1330
1216NOTE: The read buffer should only be used or modified if the C<on_read>, 1331NOTE: The read buffer should only be used or modified in the C<on_read>
1217C<push_read> or C<unshift_read> methods are used. The other read methods 1332callback or when C<push_read> or C<unshift_read> are used with a single
1218automatically manage the read buffer. 1333callback (i.e. untyped). Typed C<push_read> and C<unshift_read> methods
1334will manage the read buffer on their own.
1219 1335
1220=cut 1336=cut
1221 1337
1222sub rbuf : lvalue { 1338sub rbuf : lvalue {
1223 $_[0]{rbuf} 1339 $_[0]{rbuf}
… …
1240 1356
1241If enough data was available, then the callback must remove all data it is 1357If enough data was available, then the callback must remove all data it is
1242interested in (which can be none at all) and return a true value. After returning 1358interested in (which can be none at all) and return a true value. After returning
1243true, it will be removed from the queue. 1359true, it will be removed from the queue.
1244 1360
1361These methods may invoke callbacks (and therefore the handle might be
1362destroyed after it returns).
1363
1245=cut 1364=cut
1246 1365
1247our %RH; 1366our %RH;
1248 1367
1249sub register_read_type($$) { 1368sub register_read_type($$) {
… …
1255 my $cb = pop; 1374 my $cb = pop;
1256 1375
1257 if (@_) { 1376 if (@_) {
1258 my $type = shift; 1377 my $type = shift;
1259 1378
1379 $cb = ($RH{$type} ||= _load_func "$type\::anyevent_read_type"
1260 $cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_read") 1380 or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::push_read")
1261 ->($self, $cb, @_); 1381 ->($self, $cb, @_);
1262 } 1382 }
1263 1383
1264 push @{ $self->{_queue} }, $cb; 1384 push @{ $self->{_queue} }, $cb;
1265 $self->_drain_rbuf; 1385 $self->_drain_rbuf;
… …
1270 my $cb = pop; 1390 my $cb = pop;
1271 1391
1272 if (@_) { 1392 if (@_) {
1273 my $type = shift; 1393 my $type = shift;
1274 1394
1395 $cb = ($RH{$type} ||= _load_func "$type\::anyevent_read_type"
1275 $cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::unshift_read") 1396 or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::unshift_read")
1276 ->($self, $cb, @_); 1397 ->($self, $cb, @_);
1277 } 1398 }
1278 1399
1279 unshift @{ $self->{_queue} }, $cb; 1400 unshift @{ $self->{_queue} }, $cb;
1280 $self->_drain_rbuf; 1401 $self->_drain_rbuf;
… …
1284 1405
1285=item $handle->unshift_read (type => @args, $cb) 1406=item $handle->unshift_read (type => @args, $cb)
1286 1407
1287Instead of providing a callback that parses the data itself you can chose 1408Instead of providing a callback that parses the data itself you can chose
1288between a number of predefined parsing formats, for chunks of data, lines 1409between a number of predefined parsing formats, for chunks of data, lines
1289etc. 1410etc. You can also specify the (fully qualified) name of a package, in
1411which case AnyEvent tries to load the package and then expects to find the
1412C<anyevent_read_type> function inside (see "custom read types", below).
1290 1413
1291Predefined types are (if you have ideas for additional types, feel free to 1414Predefined types are (if you have ideas for additional types, feel free to
1292drop by and tell us): 1415drop by and tell us):
1293 1416
1294=over 4 1417=over 4
… …
1386the receive buffer when neither C<$accept> nor C<$reject> match, 1509the receive buffer when neither C<$accept> nor C<$reject> match,
1387and everything preceding and including the match will be accepted 1510and everything preceding and including the match will be accepted
1388unconditionally. This is useful to skip large amounts of data that you 1511unconditionally. This is useful to skip large amounts of data that you
1389know cannot be matched, so that the C<$accept> or C<$reject> regex do not 1512know cannot be matched, so that the C<$accept> or C<$reject> regex do not
1390have to start matching from the beginning. This is purely an optimisation 1513have to start matching from the beginning. This is purely an optimisation
1391and is usually worth only when you expect more than a few kilobytes. 1514and is usually worth it only when you expect more than a few kilobytes.
1392 1515
1393Example: expect a http header, which ends at C<\015\012\015\012>. Since we 1516Example: expect a http header, which ends at C<\015\012\015\012>. Since we
1394expect the header to be very large (it isn't in practise, but...), we use 1517expect the header to be very large (it isn't in practice, but...), we use
1395a skip regex to skip initial portions. The skip regex is tricky in that 1518a skip regex to skip initial portions. The skip regex is tricky in that
1396it only accepts something not ending in either \015 or \012, as these are 1519it only accepts something not ending in either \015 or \012, as these are
1397required for the accept regex. 1520required for the accept regex.
1398 1521
1399 $handle->push_read (regex => 1522 $handle->push_read (regex =>
… …
1613 } 1736 }
1614}; 1737};
1615 1738
1616=back 1739=back
1617 1740
1618=item AnyEvent::Handle::register_read_type type => $coderef->($handle, $cb, @args) 1741=item custom read types - Package::anyevent_read_type $handle, $cb, @args
1619 1742
1620This function (not method) lets you add your own types to C<push_read>. 1743Instead of one of the predefined types, you can also specify the name
1744of a package. AnyEvent will try to load the package and then expects to
1745find a function named C<anyevent_read_type> inside. If it isn't found, it
1746progressively tries to load the parent package until it either finds the
1747function (good) or runs out of packages (bad).
1621 1748
1622Whenever the given C<type> is used, C<push_read> will invoke the code 1749Whenever this type is used, C<push_read> will invoke the function with the
1623reference with the handle object, the callback and the remaining 1750handle object, the original callback and the remaining arguments.
1624arguments.
1625 1751
1626The code reference is supposed to return a callback (usually a closure) 1752The function is supposed to return a callback (usually a closure) that
1627that works as a plain read callback (see C<< ->push_read ($cb) >>). 1753works as a plain read callback (see C<< ->push_read ($cb) >>), so you can
1754mentally treat the function as a "configurable read type to read callback"
1755converter.
1628 1756
1629It should invoke the passed callback when it is done reading (remember to 1757It should invoke the original callback when it is done reading (remember
1630pass C<$handle> as first argument as all other callbacks do that). 1758to pass C<$handle> as first argument as all other callbacks do that,
1759although there is no strict requirement on this).
1631 1760
1632Note that this is a function, and all types registered this way will be
1633global, so try to use unique names.
1634
1635For examples, see the source of this module (F<perldoc -m AnyEvent::Handle>, 1761For examples, see the source of this module (F<perldoc -m
1636search for C<register_read_type>)). 1762AnyEvent::Handle>, search for C<register_read_type>)).
1637 1763
1638=item $handle->stop_read 1764=item $handle->stop_read
1639 1765
1640=item $handle->start_read 1766=item $handle->start_read
1641 1767
… …
1647Note that AnyEvent::Handle will automatically C<start_read> for you when 1773Note that AnyEvent::Handle will automatically C<start_read> for you when
1648you change the C<on_read> callback or push/unshift a read callback, and it 1774you change the C<on_read> callback or push/unshift a read callback, and it
1649will automatically C<stop_read> for you when neither C<on_read> is set nor 1775will automatically C<stop_read> for you when neither C<on_read> is set nor
1650there are any read requests in the queue. 1776there are any read requests in the queue.
1651 1777
1652These methods will have no effect when in TLS mode (as TLS doesn't support 1778In older versions of this module (<= 5.3), these methods had no effect,
1653half-duplex connections). 1779as TLS does not support half-duplex connections. In current versions they
1780work as expected, as this behaviour is required to avoid certain resource
1781attacks, where the program would be forced to read (and buffer) arbitrary
1782amounts of data before being able to send some data. The drawback is that
1783some readings of the the SSL/TLS specifications basically require this
1784attack to be working, as SSL/TLS implementations might stall sending data
1785during a rehandshake.
1786
1787As a guideline, during the initial handshake, you should not stop reading,
1788and as a client, it might cause problems, depending on your applciation.
1654 1789
1655=cut 1790=cut
1656 1791
1657sub stop_read { 1792sub stop_read {
1658 my ($self) = @_; 1793 my ($self) = @_;
1659 1794
1660 delete $self->{_rw} unless $self->{tls}; 1795 delete $self->{_rw};
1661} 1796}
1662 1797
1663sub start_read { 1798sub start_read {
1664 my ($self) = @_; 1799 my ($self) = @_;
1665 1800
1666 unless ($self->{_rw} || $self->{_eof}) { 1801 unless ($self->{_rw} || $self->{_eof} || !$self->{fh}) {
1667 Scalar::Util::weaken $self; 1802 Scalar::Util::weaken $self;
1668 1803
1669 $self->{_rw} = AE::io $self->{fh}, 0, sub { 1804 $self->{_rw} = AE::io $self->{fh}, 0, sub {
1670 my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf}); 1805 my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf});
1671 my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf; 1806 my $len = sysread $self->{fh}, $$rbuf, $self->{read_size}, length $$rbuf;
1672 1807
1673 if ($len > 0) { 1808 if ($len > 0) {
1674 $self->{_activity} = $self->{_ractivity} = AE::now; 1809 $self->{_activity} = $self->{_ractivity} = AE::now;
1675 1810
1676 if ($self->{tls}) { 1811 if ($self->{tls}) {
1677 Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf); 1812 Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf);
1678 1813
1679 &_dotls ($self); 1814 &_dotls ($self);
1680 } else { 1815 } else {
1681 $self->_drain_rbuf; 1816 $self->_drain_rbuf;
1817 }
1818
1819 if ($len == $self->{read_size}) {
1820 $self->{read_size} *= 2;
1821 $self->{read_size} = $self->{max_read_size} || MAX_READ_SIZE
1822 if $self->{read_size} > ($self->{max_read_size} || MAX_READ_SIZE);
1682 } 1823 }
1683 1824
1684 } elsif (defined $len) { 1825 } elsif (defined $len) {
1685 delete $self->{_rw}; 1826 delete $self->{_rw};
1686 $self->{_eof} = 1; 1827 $self->{_eof} = 1;
… …
1764 && ($tmp != $ERROR_SYSCALL || $!); 1905 && ($tmp != $ERROR_SYSCALL || $!);
1765 1906
1766 while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) { 1907 while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) {
1767 $self->{wbuf} .= $tmp; 1908 $self->{wbuf} .= $tmp;
1768 $self->_drain_wbuf; 1909 $self->_drain_wbuf;
1910 $self->{tls} or return; # tls session might have gone away in callback
1769 } 1911 }
1770 1912
1771 $self->{_on_starttls} 1913 $self->{_on_starttls}
1772 and Net::SSLeay::state ($self->{tls}) == Net::SSLeay::ST_OK () 1914 and Net::SSLeay::state ($self->{tls}) == Net::SSLeay::ST_OK ()
1773 and (delete $self->{_on_starttls})->($self, 1, "TLS/SSL connection established"); 1915 and (delete $self->{_on_starttls})->($self, 1, "TLS/SSL connection established");
… …
1795context in C<< $handle->{tls_ctx} >> after this call and can be used or 1937context in C<< $handle->{tls_ctx} >> after this call and can be used or
1796changed to your liking. Note that the handshake might have already started 1938changed to your liking. Note that the handshake might have already started
1797when this function returns. 1939when this function returns.
1798 1940
1799Due to bugs in OpenSSL, it might or might not be possible to do multiple 1941Due to bugs in OpenSSL, it might or might not be possible to do multiple
1800handshakes on the same stream. Best do not attempt to use the stream after 1942handshakes on the same stream. It is best to not attempt to use the
1801stopping TLS. 1943stream after stopping TLS.
1944
1945This method may invoke callbacks (and therefore the handle might be
1946destroyed after it returns).
1802 1947
1803=cut 1948=cut
1804 1949
1805our %TLS_CACHE; #TODO not yet documented, should we? 1950our %TLS_CACHE; #TODO not yet documented, should we?
1806 1951
… …
1872 2017
1873=item $handle->stoptls 2018=item $handle->stoptls
1874 2019
1875Shuts down the SSL connection - this makes a proper EOF handshake by 2020Shuts down the SSL connection - this makes a proper EOF handshake by
1876sending a close notify to the other side, but since OpenSSL doesn't 2021sending a close notify to the other side, but since OpenSSL doesn't
1877support non-blocking shut downs, it is not guarenteed that you can re-use 2022support non-blocking shut downs, it is not guaranteed that you can re-use
1878the stream afterwards. 2023the stream afterwards.
2024
2025This method may invoke callbacks (and therefore the handle might be
2026destroyed after it returns).
1879 2027
1880=cut 2028=cut
1881 2029
1882sub stoptls { 2030sub stoptls {
1883 my ($self) = @_; 2031 my ($self) = @_;
1884 2032
1885 if ($self->{tls}) { 2033 if ($self->{tls} && $self->{fh}) {
1886 Net::SSLeay::shutdown ($self->{tls}); 2034 Net::SSLeay::shutdown ($self->{tls});
1887 2035
1888 &_dotls; 2036 &_dotls;
1889 2037
1890# # we don't give a shit. no, we do, but we can't. no...#d# 2038# # we don't give a shit. no, we do, but we can't. no...#d#
… …
1920 push @linger, AE::io $fh, 1, sub { 2068 push @linger, AE::io $fh, 1, sub {
1921 my $len = syswrite $fh, $wbuf, length $wbuf; 2069 my $len = syswrite $fh, $wbuf, length $wbuf;
1922 2070
1923 if ($len > 0) { 2071 if ($len > 0) {
1924 substr $wbuf, 0, $len, ""; 2072 substr $wbuf, 0, $len, "";
1925 } else { 2073 } elsif (defined $len || ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK)) {
1926 @linger = (); # end 2074 @linger = (); # end
1927 } 2075 }
1928 }; 2076 };
1929 push @linger, AE::timer $linger, 0, sub { 2077 push @linger, AE::timer $linger, 0, sub {
1930 @linger = (); 2078 @linger = ();
… …
1967 2115
1968sub AnyEvent::Handle::destroyed::AUTOLOAD { 2116sub AnyEvent::Handle::destroyed::AUTOLOAD {
1969 #nop 2117 #nop
1970} 2118}
1971 2119
2120=item $handle->destroyed
2121
2122Returns false as long as the handle hasn't been destroyed by a call to C<<
2123->destroy >>, true otherwise.
2124
2125Can be useful to decide whether the handle is still valid after some
2126callback possibly destroyed the handle. For example, C<< ->push_write >>,
2127C<< ->starttls >> and other methods can call user callbacks, which in turn
2128can destroy the handle, so work can be avoided by checking sometimes:
2129
2130 $hdl->starttls ("accept");
2131 return if $hdl->destroyed;
2132 $hdl->push_write (...
2133
2134Note that the call to C<push_write> will silently be ignored if the handle
2135has been destroyed, so often you can just ignore the possibility of the
2136handle being destroyed.
2137
2138=cut
2139
2140sub destroyed { 0 }
2141sub AnyEvent::Handle::destroyed::destroyed { 1 }
2142
1972=item AnyEvent::Handle::TLS_CTX 2143=item AnyEvent::Handle::TLS_CTX
1973 2144
1974This function creates and returns the AnyEvent::TLS object used by default 2145This function creates and returns the AnyEvent::TLS object used by default
1975for TLS mode. 2146for TLS mode.
1976 2147
… …
2003 2174
2004It is only safe to "forget" the reference inside EOF or error callbacks, 2175It is only safe to "forget" the reference inside EOF or error callbacks,
2005from within all other callbacks, you need to explicitly call the C<< 2176from within all other callbacks, you need to explicitly call the C<<
2006->destroy >> method. 2177->destroy >> method.
2007 2178
2179=item Why is my C<on_eof> callback never called?
2180
2181Probably because your C<on_error> callback is being called instead: When
2182you have outstanding requests in your read queue, then an EOF is
2183considered an error as you clearly expected some data.
2184
2185To avoid this, make sure you have an empty read queue whenever your handle
2186is supposed to be "idle" (i.e. connection closes are O.K.). You cna set
2187an C<on_read> handler that simply pushes the first read requests in the
2188queue.
2189
2190See also the next question, which explains this in a bit more detail.
2191
2192=item How can I serve requests in a loop?
2193
2194Most protocols consist of some setup phase (authentication for example)
2195followed by a request handling phase, where the server waits for requests
2196and handles them, in a loop.
2197
2198There are two important variants: The first (traditional, better) variant
2199handles requests until the server gets some QUIT command, causing it to
2200close the connection first (highly desirable for a busy TCP server). A
2201client dropping the connection is an error, which means this variant can
2202detect an unexpected detection close.
2203
2204To handle this case, always make sure you have a on-empty read queue, by
2205pushing the "read request start" handler on it:
2206
2207 # we assume a request starts with a single line
2208 my @start_request; @start_request = (line => sub {
2209 my ($hdl, $line) = @_;
2210
2211 ... handle request
2212
2213 # push next request read, possibly from a nested callback
2214 $hdl->push_read (@start_request);
2215 });
2216
2217 # auth done, now go into request handling loop
2218 # now push the first @start_request
2219 $hdl->push_read (@start_request);
2220
2221By always having an outstanding C<push_read>, the handle always expects
2222some data and raises the C<EPIPE> error when the connction is dropped
2223unexpectedly.
2224
2225The second variant is a protocol where the client can drop the connection
2226at any time. For TCP, this means that the server machine may run out of
2227sockets easier, and in general, it means you cnanot distinguish a protocl
2228failure/client crash from a normal connection close. Nevertheless, these
2229kinds of protocols are common (and sometimes even the best solution to the
2230problem).
2231
2232Having an outstanding read request at all times is possible if you ignore
2233C<EPIPE> errors, but this doesn't help with when the client drops the
2234connection during a request, which would still be an error.
2235
2236A better solution is to push the initial request read in an C<on_read>
2237callback. This avoids an error, as when the server doesn't expect data
2238(i.e. is idly waiting for the next request, an EOF will not raise an
2239error, but simply result in an C<on_eof> callback. It is also a bit slower
2240and simpler:
2241
2242 # auth done, now go into request handling loop
2243 $hdl->on_read (sub {
2244 my ($hdl) = @_;
2245
2246 # called each time we receive data but the read queue is empty
2247 # simply start read the request
2248
2249 $hdl->push_read (line => sub {
2250 my ($hdl, $line) = @_;
2251
2252 ... handle request
2253
2254 # do nothing special when the request has been handled, just
2255 # let the request queue go empty.
2256 });
2257 });
2258
2008=item I get different callback invocations in TLS mode/Why can't I pause 2259=item I get different callback invocations in TLS mode/Why can't I pause
2009reading? 2260reading?
2010 2261
2011Unlike, say, TCP, TLS connections do not consist of two independent 2262Unlike, say, TCP, TLS connections do not consist of two independent
2012communication channels, one for each direction. Or put differently. The 2263communication channels, one for each direction. Or put differently, the
2013read and write directions are not independent of each other: you cannot 2264read and write directions are not independent of each other: you cannot
2014write data unless you are also prepared to read, and vice versa. 2265write data unless you are also prepared to read, and vice versa.
2015 2266
2016This can mean than, in TLS mode, you might get C<on_error> or C<on_eof> 2267This means that, in TLS mode, you might get C<on_error> or C<on_eof>
2017callback invocations when you are not expecting any read data - the reason 2268callback invocations when you are not expecting any read data - the reason
2018is that AnyEvent::Handle always reads in TLS mode. 2269is that AnyEvent::Handle always reads in TLS mode.
2019 2270
2020During the connection, you have to make sure that you always have a 2271During the connection, you have to make sure that you always have a
2021non-empty read-queue, or an C<on_read> watcher. At the end of the 2272non-empty read-queue, or an C<on_read> watcher. At the end of the
… …
2035 my $data = delete $_[0]{rbuf}; 2286 my $data = delete $_[0]{rbuf};
2036 }); 2287 });
2037 2288
2038The reason to use C<on_error> is that TCP connections, due to latencies 2289The reason to use C<on_error> is that TCP connections, due to latencies
2039and packets loss, might get closed quite violently with an error, when in 2290and packets loss, might get closed quite violently with an error, when in
2040fact, all data has been received. 2291fact all data has been received.
2041 2292
2042It is usually better to use acknowledgements when transferring data, 2293It is usually better to use acknowledgements when transferring data,
2043to make sure the other side hasn't just died and you got the data 2294to make sure the other side hasn't just died and you got the data
2044intact. This is also one reason why so many internet protocols have an 2295intact. This is also one reason why so many internet protocols have an
2045explicit QUIT command. 2296explicit QUIT command.
… …
2062consider using C<< ->push_shutdown >> instead. 2313consider using C<< ->push_shutdown >> instead.
2063 2314
2064=item I want to contact a TLS/SSL server, I don't care about security. 2315=item I want to contact a TLS/SSL server, I don't care about security.
2065 2316
2066If your TLS server is a pure TLS server (e.g. HTTPS) that only speaks TLS, 2317If your TLS server is a pure TLS server (e.g. HTTPS) that only speaks TLS,
2067simply connect to it and then create the AnyEvent::Handle with the C<tls> 2318connect to it and then create the AnyEvent::Handle with the C<tls>
2068parameter: 2319parameter:
2069 2320
2070 tcp_connect $host, $port, sub { 2321 tcp_connect $host, $port, sub {
2071 my ($fh) = @_; 2322 my ($fh) = @_;
2072 2323
… …
2172 2423
2173=item * all members not documented here and not prefixed with an underscore 2424=item * all members not documented here and not prefixed with an underscore
2174are free to use in subclasses. 2425are free to use in subclasses.
2175 2426
2176Of course, new versions of AnyEvent::Handle may introduce more "public" 2427Of course, new versions of AnyEvent::Handle may introduce more "public"
2177member variables, but thats just life, at least it is documented. 2428member variables, but that's just life. At least it is documented.
2178 2429
2179=back 2430=back
2180 2431
2181=head1 AUTHOR 2432=head1 AUTHOR
2182 2433

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