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 1.184 by root, Thu Sep 3 13:14:38 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
… …
319already have occured on BSD systems), but at least it will protect you 354already have occured on BSD systems), but at least it will protect you
320from most attacks. 355from most attacks.
321 356
322=item read_size => <bytes> 357=item read_size => <bytes>
323 358
324The 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
325try to read during each loop iteration, which affects memory 360read during each loop iteration. Each handle object will consume at least
326requirements). 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.
327 370
328=item low_water_mark => <bytes> 371=item low_water_mark => <bytes>
329 372
330Sets 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
331buffer: 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
332considered empty. 375considered empty.
333 376
334Sometimes it can be beneficial (for performance reasons) to add data to 377Sometimes it can be beneficial (for performance reasons) to add data to
335the 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
336the operating system kernel usually buffers data as well, so the default 379the operating system kernel usually buffers data as well, so the default
337is good in almost all cases. 380is good in almost all cases.
338 381
339=item linger => <seconds> 382=item linger => <seconds>
340 383
341If non-zero (default: C<3600>), then the destructor of the 384If this is non-zero (default: C<3600>), the destructor of the
342AnyEvent::Handle object will check whether there is still outstanding 385AnyEvent::Handle object will check whether there is still outstanding
343write 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
344socket. No errors will be reported (this mostly matches how the operating 387socket. No errors will be reported (this mostly matches how the operating
345system treats outstanding data at socket close time). 388system treats outstanding data at socket close time).
346 389
… …
353A string used to identify the remote site - usually the DNS hostname 396A string used to identify the remote site - usually the DNS hostname
354(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.
355 398
356Apart 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
357peername verification (see C<verify_peername> in L<AnyEvent::TLS>). This 400peername verification (see C<verify_peername> in L<AnyEvent::TLS>). This
358verification will be skipped when C<peername> is not specified or 401verification will be skipped when C<peername> is not specified or is
359C<undef>. 402C<undef>.
360 403
361=item tls => "accept" | "connect" | Net::SSLeay::SSL object 404=item tls => "accept" | "connect" | Net::SSLeay::SSL object
362 405
363When this parameter is given, it enables TLS (SSL) mode, that means 406When this parameter is given, it enables TLS (SSL) mode, that means
364AnyEvent 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
365established and will transparently encrypt/decrypt data afterwards. 408established and will transparently encrypt/decrypt data afterwards.
366 409
367All TLS protocol errors will be signalled as C<EPROTO>, with an 410All TLS protocol errors will be signalled as C<EPROTO>, with an
368appropriate error message. 411appropriate error message.
369 412
… …
389B<IMPORTANT:> since Net::SSLeay "objects" are really only integers, 432B<IMPORTANT:> since Net::SSLeay "objects" are really only integers,
390passing 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
391happens 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
392segmentation fault. 435segmentation fault.
393 436
394See 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.
395 438
396=item tls_ctx => $anyevent_tls 439=item tls_ctx => $anyevent_tls
397 440
398Use 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
399(unless a connection object was specified directly). If this parameter is 442(unless a connection object was specified directly). If this
400missing, 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>.
401 445
402Instead 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
403=> 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
404new TLS context object. 448new TLS context object.
405 449
… …
414 458
415TLS 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
416callback 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>.
417 461
418Without this callback, handshake failures lead to C<on_error> being 462Without this callback, handshake failures lead to C<on_error> being
419called, as normal. 463called as usual.
420 464
421Note 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
422need 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
423then call C<< ->starttls >> again. 467then call C<< ->starttls >> again.
424 468
425=item on_stoptls => $cb->($handle) 469=item on_stoptls => $cb->($handle)
426 470
… …
473 AnyEvent::Socket::tcp_connect ( 517 AnyEvent::Socket::tcp_connect (
474 $self->{connect}[0], 518 $self->{connect}[0],
475 $self->{connect}[1], 519 $self->{connect}[1],
476 sub { 520 sub {
477 my ($fh, $host, $port, $retry) = @_; 521 my ($fh, $host, $port, $retry) = @_;
522
523 delete $self->{_connect}; # no longer needed
478 524
479 if ($fh) { 525 if ($fh) {
480 $self->{fh} = $fh; 526 $self->{fh} = $fh;
481 527
482 delete $self->{_skip_drain_rbuf}; 528 delete $self->{_skip_drain_rbuf};
… …
500 }, 546 },
501 sub { 547 sub {
502 local $self->{fh} = $_[0]; 548 local $self->{fh} = $_[0];
503 549
504 $self->{on_prepare} 550 $self->{on_prepare}
505 ? $self->{on_prepare}->($self) 551 ? $self->{on_prepare}->($self)
506 : () 552 : ()
507 } 553 }
508 ); 554 );
509 } 555 }
510 556
… …
516} 562}
517 563
518sub _start { 564sub _start {
519 my ($self) = @_; 565 my ($self) = @_;
520 566
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
521 AnyEvent::Util::fh_nonblocking $self->{fh}, 1; 573 AnyEvent::Util::fh_nonblocking $self->{fh}, 1;
522 574
523 $self->{_activity} = 575 $self->{_activity} =
524 $self->{_ractivity} = 576 $self->{_ractivity} =
525 $self->{_wactivity} = AE::now; 577 $self->{_wactivity} = AE::now;
526 578
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
527 $self->timeout (delete $self->{timeout} ) if $self->{timeout}; 583 $self->timeout (delete $self->{timeout} ) if $self->{timeout};
528 $self->rtimeout (delete $self->{rtimeout} ) if $self->{rtimeout}; 584 $self->rtimeout (delete $self->{rtimeout} ) if $self->{rtimeout};
529 $self->wtimeout (delete $self->{wtimeout} ) if $self->{wtimeout}; 585 $self->wtimeout (delete $self->{wtimeout} ) if $self->{wtimeout};
530 586
531 $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};
… …
534 $self->oobinline (exists $self->{oobinline} ? delete $self->{oobinline} : 1); 590 $self->oobinline (exists $self->{oobinline} ? delete $self->{oobinline} : 1);
535 591
536 $self->starttls (delete $self->{tls}, delete $self->{tls_ctx}) 592 $self->starttls (delete $self->{tls}, delete $self->{tls_ctx})
537 if $self->{tls}; 593 if $self->{tls};
538 594
539 $self->on_drain (delete $self->{on_drain}) if $self->{on_drain}; 595 $self->on_drain (delete $self->{on_drain} ) if $self->{on_drain};
540 596
541 $self->start_read 597 $self->start_read
542 if $self->{on_read} || @{ $self->{_queue} }; 598 if $self->{on_read} || @{ $self->{_queue} };
543 599
544 $self->_drain_wbuf; 600 $self->_drain_wbuf;
… …
551 $message ||= "$!"; 607 $message ||= "$!";
552 608
553 if ($self->{on_error}) { 609 if ($self->{on_error}) {
554 $self->{on_error}($self, $fatal, $message); 610 $self->{on_error}($self, $fatal, $message);
555 $self->destroy if $fatal; 611 $self->destroy if $fatal;
556 } elsif ($self->{fh}) { 612 } elsif ($self->{fh} || $self->{connect}) {
557 $self->destroy; 613 $self->destroy;
558 Carp::croak "AnyEvent::Handle uncaught error: $message"; 614 Carp::croak "AnyEvent::Handle uncaught error: $message";
559 } 615 }
560} 616}
561 617
… …
620=cut 676=cut
621 677
622sub no_delay { 678sub no_delay {
623 $_[0]{no_delay} = $_[1]; 679 $_[0]{no_delay} = $_[1];
624 680
625 eval {
626 local $SIG{__DIE__};
627 setsockopt $_[0]{fh}, Socket::IPPROTO_TCP (), Socket::TCP_NODELAY (), int $_[1] 681 setsockopt $_[0]{fh}, Socket::IPPROTO_TCP (), Socket::TCP_NODELAY (), int $_[1]
628 if $_[0]{fh}; 682 if $_[0]{fh};
629 };
630} 683}
631 684
632=item $handle->keepalive ($boolean) 685=item $handle->keepalive ($boolean)
633 686
634Enables or disables the C<keepalive> setting (see constructor argument of 687Enables or disables the C<keepalive> setting (see constructor argument of
… …
694 747
695Replace 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).
696 749
697=cut 750=cut
698 751
699sub on_starttls { 752sub on_stoptls {
700 $_[0]{on_stoptls} = $_[1]; 753 $_[0]{on_stoptls} = $_[1];
701} 754}
702 755
703=item $handle->rbuf_max ($max_octets) 756=item $handle->rbuf_max ($max_octets)
704 757
705Configures 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).
706 763
707=cut 764=cut
708 765
709sub rbuf_max { 766sub rbuf_max {
710 $_[0]{rbuf_max} = $_[1]; 767 $_[0]{rbuf_max} = $_[1];
768}
769
770sub rbuf_max {
771 $_[0]{wbuf_max} = $_[1];
711} 772}
712 773
713############################################################################# 774#############################################################################
714 775
715=item $handle->timeout ($seconds) 776=item $handle->timeout ($seconds)
… …
743 $_[0]{$on_timeout} = $_[1]; 804 $_[0]{$on_timeout} = $_[1];
744 }; 805 };
745 806
746 *$timeout = sub { 807 *$timeout = sub {
747 my ($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";
748 812
749 $self->{$timeout} = $new_value; 813 $self->{$timeout} = $new_value;
750 delete $self->{$tw}; &$cb; 814 delete $self->{$tw}; &$cb;
751 }; 815 };
752 816
… …
816=item $handle->on_drain ($cb) 880=item $handle->on_drain ($cb)
817 881
818Sets 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
819C<on_drain> in the constructor). 883C<on_drain> in the constructor).
820 884
885This method may invoke callbacks (and therefore the handle might be
886destroyed after it returns).
887
821=cut 888=cut
822 889
823sub on_drain { 890sub on_drain {
824 my ($self, $cb) = @_; 891 my ($self, $cb) = @_;
825 892
… …
829 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});
830} 897}
831 898
832=item $handle->push_write ($data) 899=item $handle->push_write ($data)
833 900
834Queues 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
835want (only limited by the available memory), as C<AnyEvent::Handle> 902you want (only limited by the available memory and C<wbuf_max>), as
836buffers 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).
837 907
838=cut 908=cut
839 909
840sub _drain_wbuf { 910sub _drain_wbuf {
841 my ($self) = @_; 911 my ($self) = @_;
… …
866 $cb->() unless $self->{autocork}; 936 $cb->() unless $self->{autocork};
867 937
868 # if still data left in wbuf, we need to poll 938 # if still data left in wbuf, we need to poll
869 $self->{_ww} = AE::io $self->{fh}, 1, $cb 939 $self->{_ww} = AE::io $self->{fh}, 1, $cb
870 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 }
871 }; 948 };
872} 949}
873 950
874our %WH; 951our %WH;
875 952
953# deprecated
876sub register_write_type($$) { 954sub register_write_type($$) {
877 $WH{$_[0]} = $_[1]; 955 $WH{$_[0]} = $_[1];
878} 956}
879 957
880sub push_write { 958sub push_write {
881 my $self = shift; 959 my $self = shift;
882 960
883 if (@_ > 1) { 961 if (@_ > 1) {
884 my $type = shift; 962 my $type = shift;
885 963
964 @_ = ($WH{$type} ||= _load_func "$type\::anyevent_write_type"
886 @_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write") 965 or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::push_write")
887 ->($self, @_); 966 ->($self, @_);
888 } 967 }
889 968
969 # we downgrade here to avoid hard-to-track-down bugs,
970 # and diagnose the problem earlier and better.
971
890 if ($self->{tls}) { 972 if ($self->{tls}) {
891 $self->{_tls_wbuf} .= $_[0]; 973 utf8::downgrade $self->{_tls_wbuf} .= $_[0];
892 &_dotls ($self) if $self->{fh}; 974 &_dotls ($self) if $self->{fh};
893 } else { 975 } else {
894 $self->{wbuf} .= $_[0]; 976 utf8::downgrade $self->{wbuf} .= $_[0];
895 $self->_drain_wbuf if $self->{fh}; 977 $self->_drain_wbuf if $self->{fh};
896 } 978 }
897} 979}
898 980
899=item $handle->push_write (type => @args) 981=item $handle->push_write (type => @args)
900 982
901Instead of formatting your data yourself, you can also let this module do 983Instead of formatting your data yourself, you can also let this module
902the 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).
903 988
904Predefined 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
905drop by and tell us): 990drop by and tell us):
906 991
907=over 4 992=over 4
… …
1002before 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
1003C<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
1004C<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
1005replaces the C<on_drain> callback with: 1090replaces the C<on_drain> callback with:
1006 1091
1007 sub { shutdown $_[0]{fh}, 1 } # for push_shutdown 1092 sub { shutdown $_[0]{fh}, 1 }
1008 1093
1009This simply shuts down the write side and signals an EOF condition to the 1094This simply shuts down the write side and signals an EOF condition to the
1010the peer. 1095the peer.
1011 1096
1012You can rely on the normal read queue and C<on_eof> handling 1097You can rely on the normal read queue and C<on_eof> handling
1013afterwards. This is the cleanest way to close a connection. 1098afterwards. This is the cleanest way to close a connection.
1014 1099
1100This method may invoke callbacks (and therefore the handle might be
1101destroyed after it returns).
1102
1015=cut 1103=cut
1016 1104
1017sub push_shutdown { 1105sub push_shutdown {
1018 my ($self) = @_; 1106 my ($self) = @_;
1019 1107
1020 delete $self->{low_water_mark}; 1108 delete $self->{low_water_mark};
1021 $self->on_drain (sub { shutdown $_[0]{fh}, 1 }); 1109 $self->on_drain (sub { shutdown $_[0]{fh}, 1 });
1022} 1110}
1023 1111
1024=item AnyEvent::Handle::register_write_type type => $coderef->($handle, @args) 1112=item custom write types - Package::anyevent_write_type $handle, @args
1025 1113
1026This 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
1027Whenever 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
1028reference with the handle object and the remaining arguments. 1121the handle object and the remaining arguments.
1029 1122
1030The 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
1031be 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.
1032 1126
1033Note 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
1034global, 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 }
1035 1143
1036=cut 1144=cut
1037 1145
1038############################################################################# 1146#############################################################################
1039 1147
… …
1048ways, 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
1049a queue. 1157a queue.
1050 1158
1051In 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
1052new 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
1053enough is there) from the read buffer (C<< $handle->rbuf >>). Or you cna 1161enough is there) from the read buffer (C<< $handle->rbuf >>). Or you can
1054leave the data there if you want to accumulate more (e.g. when only a 1162leave the data there if you want to accumulate more (e.g. when only a
1055partial message has been received so far). 1163partial message has been received so far), or change the read queue with
1164e.g. C<push_read>.
1056 1165
1057In the more complex case, you want to queue multiple callbacks. In this 1166In the more complex case, you want to queue multiple callbacks. In this
1058case, AnyEvent::Handle will call the first queued callback each time new 1167case, AnyEvent::Handle will call the first queued callback each time new
1059data arrives (also the first time it is queued) and removes it when it has 1168data arrives (also the first time it is queued) and remove it when it has
1060done its job (see C<push_read>, below). 1169done its job (see C<push_read>, below).
1061 1170
1062This way you can, for example, push three line-reads, followed by reading 1171This way you can, for example, push three line-reads, followed by reading
1063a chunk of data, and AnyEvent::Handle will execute them in order. 1172a chunk of data, and AnyEvent::Handle will execute them in order.
1064 1173
… …
1195 1304
1196This replaces the currently set C<on_read> callback, or clears it (when 1305This replaces the currently set C<on_read> callback, or clears it (when
1197the new callback is C<undef>). See the description of C<on_read> in the 1306the new callback is C<undef>). See the description of C<on_read> in the
1198constructor. 1307constructor.
1199 1308
1309This method may invoke callbacks (and therefore the handle might be
1310destroyed after it returns).
1311
1200=cut 1312=cut
1201 1313
1202sub on_read { 1314sub on_read {
1203 my ($self, $cb) = @_; 1315 my ($self, $cb) = @_;
1204 1316
… …
1206 $self->_drain_rbuf if $cb; 1318 $self->_drain_rbuf if $cb;
1207} 1319}
1208 1320
1209=item $handle->rbuf 1321=item $handle->rbuf
1210 1322
1211Returns 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).
1212 1326
1213You can access the read buffer directly as the C<< ->{rbuf} >> 1327The only operation allowed on the read buffer (apart from looking at it)
1214member, if you want. However, the only operation allowed on the 1328is removing data from its beginning. Otherwise modifying or appending to
1215read buffer (apart from looking at it) is removing data from its 1329it is not allowed and will lead to hard-to-track-down bugs.
1216beginning. Otherwise modifying or appending to it is not allowed and will
1217lead to hard-to-track-down bugs.
1218 1330
1219NOTE: 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>
1220C<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
1221automatically 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.
1222 1335
1223=cut 1336=cut
1224 1337
1225sub rbuf : lvalue { 1338sub rbuf : lvalue {
1226 $_[0]{rbuf} 1339 $_[0]{rbuf}
… …
1243 1356
1244If 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
1245interested 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
1246true, it will be removed from the queue. 1359true, it will be removed from the queue.
1247 1360
1361These methods may invoke callbacks (and therefore the handle might be
1362destroyed after it returns).
1363
1248=cut 1364=cut
1249 1365
1250our %RH; 1366our %RH;
1251 1367
1252sub register_read_type($$) { 1368sub register_read_type($$) {
… …
1258 my $cb = pop; 1374 my $cb = pop;
1259 1375
1260 if (@_) { 1376 if (@_) {
1261 my $type = shift; 1377 my $type = shift;
1262 1378
1379 $cb = ($RH{$type} ||= _load_func "$type\::anyevent_read_type"
1263 $cb = ($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")
1264 ->($self, $cb, @_); 1381 ->($self, $cb, @_);
1265 } 1382 }
1266 1383
1267 push @{ $self->{_queue} }, $cb; 1384 push @{ $self->{_queue} }, $cb;
1268 $self->_drain_rbuf; 1385 $self->_drain_rbuf;
… …
1273 my $cb = pop; 1390 my $cb = pop;
1274 1391
1275 if (@_) { 1392 if (@_) {
1276 my $type = shift; 1393 my $type = shift;
1277 1394
1395 $cb = ($RH{$type} ||= _load_func "$type\::anyevent_read_type"
1278 $cb = ($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")
1279 ->($self, $cb, @_); 1397 ->($self, $cb, @_);
1280 } 1398 }
1281 1399
1282 unshift @{ $self->{_queue} }, $cb; 1400 unshift @{ $self->{_queue} }, $cb;
1283 $self->_drain_rbuf; 1401 $self->_drain_rbuf;
… …
1287 1405
1288=item $handle->unshift_read (type => @args, $cb) 1406=item $handle->unshift_read (type => @args, $cb)
1289 1407
1290Instead of providing a callback that parses the data itself you can chose 1408Instead of providing a callback that parses the data itself you can chose
1291between a number of predefined parsing formats, for chunks of data, lines 1409between a number of predefined parsing formats, for chunks of data, lines
1292etc. 1410etc. You can also specify the (fully qualified) name of a package, in
1411which case AnyEvent tries to load the package and then expects to find the
1412C<anyevent_read_type> function inside (see "custom read types", below).
1293 1413
1294Predefined types are (if you have ideas for additional types, feel free to 1414Predefined types are (if you have ideas for additional types, feel free to
1295drop by and tell us): 1415drop by and tell us):
1296 1416
1297=over 4 1417=over 4
… …
1389the receive buffer when neither C<$accept> nor C<$reject> match, 1509the receive buffer when neither C<$accept> nor C<$reject> match,
1390and everything preceding and including the match will be accepted 1510and everything preceding and including the match will be accepted
1391unconditionally. This is useful to skip large amounts of data that you 1511unconditionally. This is useful to skip large amounts of data that you
1392know cannot be matched, so that the C<$accept> or C<$reject> regex do not 1512know cannot be matched, so that the C<$accept> or C<$reject> regex do not
1393have to start matching from the beginning. This is purely an optimisation 1513have to start matching from the beginning. This is purely an optimisation
1394and 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.
1395 1515
1396Example: 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
1397expect 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
1398a 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
1399it 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
1400required for the accept regex. 1520required for the accept regex.
1401 1521
1402 $handle->push_read (regex => 1522 $handle->push_read (regex =>
… …
1616 } 1736 }
1617}; 1737};
1618 1738
1619=back 1739=back
1620 1740
1621=item AnyEvent::Handle::register_read_type type => $coderef->($handle, $cb, @args) 1741=item custom read types - Package::anyevent_read_type $handle, $cb, @args
1622 1742
1623This function (not method) lets you add your own types to C<push_read>. 1743Instead of one of the predefined types, you can also specify the name
1744of a package. AnyEvent will try to load the package and then expects to
1745find a function named C<anyevent_read_type> inside. If it isn't found, it
1746progressively tries to load the parent package until it either finds the
1747function (good) or runs out of packages (bad).
1624 1748
1625Whenever the given C<type> is used, C<push_read> will invoke the code 1749Whenever this type is used, C<push_read> will invoke the function with the
1626reference with the handle object, the callback and the remaining 1750handle object, the original callback and the remaining arguments.
1627arguments.
1628 1751
1629The code reference is supposed to return a callback (usually a closure) 1752The function is supposed to return a callback (usually a closure) that
1630that works as a plain read callback (see C<< ->push_read ($cb) >>). 1753works as a plain read callback (see C<< ->push_read ($cb) >>), so you can
1754mentally treat the function as a "configurable read type to read callback"
1755converter.
1631 1756
1632It should invoke the passed callback when it is done reading (remember to 1757It should invoke the original callback when it is done reading (remember
1633pass C<$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).
1634 1760
1635Note that this is a function, and all types registered this way will be
1636global, so try to use unique names.
1637
1638For examples, see the source of this module (F<perldoc -m AnyEvent::Handle>, 1761For examples, see the source of this module (F<perldoc -m
1639search for C<register_read_type>)). 1762AnyEvent::Handle>, search for C<register_read_type>)).
1640 1763
1641=item $handle->stop_read 1764=item $handle->stop_read
1642 1765
1643=item $handle->start_read 1766=item $handle->start_read
1644 1767
… …
1650Note that AnyEvent::Handle will automatically C<start_read> for you when 1773Note that AnyEvent::Handle will automatically C<start_read> for you when
1651you change the C<on_read> callback or push/unshift a read callback, and it 1774you change the C<on_read> callback or push/unshift a read callback, and it
1652will automatically C<stop_read> for you when neither C<on_read> is set nor 1775will automatically C<stop_read> for you when neither C<on_read> is set nor
1653there are any read requests in the queue. 1776there are any read requests in the queue.
1654 1777
1655These methods will have no effect when in TLS mode (as TLS doesn't support 1778In older versions of this module (<= 5.3), these methods had no effect,
1656half-duplex connections). 1779as TLS does not support half-duplex connections. In current versions they
1780work as expected, as this behaviour is required to avoid certain resource
1781attacks, where the program would be forced to read (and buffer) arbitrary
1782amounts of data before being able to send some data. The drawback is that
1783some readings of the the SSL/TLS specifications basically require this
1784attack to be working, as SSL/TLS implementations might stall sending data
1785during a rehandshake.
1786
1787As a guideline, during the initial handshake, you should not stop reading,
1788and as a client, it might cause problems, depending on your applciation.
1657 1789
1658=cut 1790=cut
1659 1791
1660sub stop_read { 1792sub stop_read {
1661 my ($self) = @_; 1793 my ($self) = @_;
1662 1794
1663 delete $self->{_rw} unless $self->{tls}; 1795 delete $self->{_rw};
1664} 1796}
1665 1797
1666sub start_read { 1798sub start_read {
1667 my ($self) = @_; 1799 my ($self) = @_;
1668 1800
1669 unless ($self->{_rw} || $self->{_eof}) { 1801 unless ($self->{_rw} || $self->{_eof} || !$self->{fh}) {
1670 Scalar::Util::weaken $self; 1802 Scalar::Util::weaken $self;
1671 1803
1672 $self->{_rw} = AE::io $self->{fh}, 0, sub { 1804 $self->{_rw} = AE::io $self->{fh}, 0, sub {
1673 my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf}); 1805 my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf});
1674 my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf; 1806 my $len = sysread $self->{fh}, $$rbuf, $self->{read_size}, length $$rbuf;
1675 1807
1676 if ($len > 0) { 1808 if ($len > 0) {
1677 $self->{_activity} = $self->{_ractivity} = AE::now; 1809 $self->{_activity} = $self->{_ractivity} = AE::now;
1678 1810
1679 if ($self->{tls}) { 1811 if ($self->{tls}) {
1680 Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf); 1812 Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf);
1681 1813
1682 &_dotls ($self); 1814 &_dotls ($self);
1683 } else { 1815 } else {
1684 $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);
1685 } 1823 }
1686 1824
1687 } elsif (defined $len) { 1825 } elsif (defined $len) {
1688 delete $self->{_rw}; 1826 delete $self->{_rw};
1689 $self->{_eof} = 1; 1827 $self->{_eof} = 1;
… …
1767 && ($tmp != $ERROR_SYSCALL || $!); 1905 && ($tmp != $ERROR_SYSCALL || $!);
1768 1906
1769 while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) { 1907 while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) {
1770 $self->{wbuf} .= $tmp; 1908 $self->{wbuf} .= $tmp;
1771 $self->_drain_wbuf; 1909 $self->_drain_wbuf;
1910 $self->{tls} or return; # tls session might have gone away in callback
1772 } 1911 }
1773 1912
1774 $self->{_on_starttls} 1913 $self->{_on_starttls}
1775 and Net::SSLeay::state ($self->{tls}) == Net::SSLeay::ST_OK () 1914 and Net::SSLeay::state ($self->{tls}) == Net::SSLeay::ST_OK ()
1776 and (delete $self->{_on_starttls})->($self, 1, "TLS/SSL connection established"); 1915 and (delete $self->{_on_starttls})->($self, 1, "TLS/SSL connection established");
… …
1798context 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
1799changed to your liking. Note that the handshake might have already started 1938changed to your liking. Note that the handshake might have already started
1800when this function returns. 1939when this function returns.
1801 1940
1802Due 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
1803handshakes 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
1804stopping TLS. 1943stream after stopping TLS.
1944
1945This method may invoke callbacks (and therefore the handle might be
1946destroyed after it returns).
1805 1947
1806=cut 1948=cut
1807 1949
1808our %TLS_CACHE; #TODO not yet documented, should we? 1950our %TLS_CACHE; #TODO not yet documented, should we?
1809 1951
… …
1875 2017
1876=item $handle->stoptls 2018=item $handle->stoptls
1877 2019
1878Shuts down the SSL connection - this makes a proper EOF handshake by 2020Shuts down the SSL connection - this makes a proper EOF handshake by
1879sending a close notify to the other side, but since OpenSSL doesn't 2021sending a close notify to the other side, but since OpenSSL doesn't
1880support non-blocking shut downs, it is not guarenteed that you can re-use 2022support non-blocking shut downs, it is not guaranteed that you can re-use
1881the stream afterwards. 2023the stream afterwards.
2024
2025This method may invoke callbacks (and therefore the handle might be
2026destroyed after it returns).
1882 2027
1883=cut 2028=cut
1884 2029
1885sub stoptls { 2030sub stoptls {
1886 my ($self) = @_; 2031 my ($self) = @_;
1887 2032
1888 if ($self->{tls}) { 2033 if ($self->{tls} && $self->{fh}) {
1889 Net::SSLeay::shutdown ($self->{tls}); 2034 Net::SSLeay::shutdown ($self->{tls});
1890 2035
1891 &_dotls; 2036 &_dotls;
1892 2037
1893# # 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#
… …
1923 push @linger, AE::io $fh, 1, sub { 2068 push @linger, AE::io $fh, 1, sub {
1924 my $len = syswrite $fh, $wbuf, length $wbuf; 2069 my $len = syswrite $fh, $wbuf, length $wbuf;
1925 2070
1926 if ($len > 0) { 2071 if ($len > 0) {
1927 substr $wbuf, 0, $len, ""; 2072 substr $wbuf, 0, $len, "";
1928 } else { 2073 } elsif (defined $len || ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK)) {
1929 @linger = (); # end 2074 @linger = (); # end
1930 } 2075 }
1931 }; 2076 };
1932 push @linger, AE::timer $linger, 0, sub { 2077 push @linger, AE::timer $linger, 0, sub {
1933 @linger = (); 2078 @linger = ();
… …
1970 2115
1971sub AnyEvent::Handle::destroyed::AUTOLOAD { 2116sub AnyEvent::Handle::destroyed::AUTOLOAD {
1972 #nop 2117 #nop
1973} 2118}
1974 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
1975=item AnyEvent::Handle::TLS_CTX 2143=item AnyEvent::Handle::TLS_CTX
1976 2144
1977This function creates and returns the AnyEvent::TLS object used by default 2145This function creates and returns the AnyEvent::TLS object used by default
1978for TLS mode. 2146for TLS mode.
1979 2147
… …
2006 2174
2007It 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,
2008from within all other callbacks, you need to explicitly call the C<< 2176from within all other callbacks, you need to explicitly call the C<<
2009->destroy >> method. 2177->destroy >> method.
2010 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
2011=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
2012reading? 2260reading?
2013 2261
2014Unlike, say, TCP, TLS connections do not consist of two independent 2262Unlike, say, TCP, TLS connections do not consist of two independent
2015communication channels, one for each direction. Or put differently. The 2263communication channels, one for each direction. Or put differently, the
2016read and write directions are not independent of each other: you cannot 2264read and write directions are not independent of each other: you cannot
2017write data unless you are also prepared to read, and vice versa. 2265write data unless you are also prepared to read, and vice versa.
2018 2266
2019This 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>
2020callback invocations when you are not expecting any read data - the reason 2268callback invocations when you are not expecting any read data - the reason
2021is that AnyEvent::Handle always reads in TLS mode. 2269is that AnyEvent::Handle always reads in TLS mode.
2022 2270
2023During 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
2024non-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
… …
2038 my $data = delete $_[0]{rbuf}; 2286 my $data = delete $_[0]{rbuf};
2039 }); 2287 });
2040 2288
2041The 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
2042and 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
2043fact, all data has been received. 2291fact all data has been received.
2044 2292
2045It is usually better to use acknowledgements when transferring data, 2293It is usually better to use acknowledgements when transferring data,
2046to 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
2047intact. 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
2048explicit QUIT command. 2296explicit QUIT command.
… …
2065consider using C<< ->push_shutdown >> instead. 2313consider using C<< ->push_shutdown >> instead.
2066 2314
2067=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.
2068 2316
2069If 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,
2070simply 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>
2071parameter: 2319parameter:
2072 2320
2073 tcp_connect $host, $port, sub { 2321 tcp_connect $host, $port, sub {
2074 my ($fh) = @_; 2322 my ($fh) = @_;
2075 2323
… …
2175 2423
2176=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
2177are free to use in subclasses. 2425are free to use in subclasses.
2178 2426
2179Of course, new versions of AnyEvent::Handle may introduce more "public" 2427Of course, new versions of AnyEvent::Handle may introduce more "public"
2180member variables, but thats just life, at least it is documented. 2428member variables, but that's just life. At least it is documented.
2181 2429
2182=back 2430=back
2183 2431
2184=head1 AUTHOR 2432=head1 AUTHOR
2185 2433

Diff Legend

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