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Revision 1.178 by root, Tue Aug 11 01:15:17 2009 UTC vs.
Revision 1.224 by root, Mon Sep 5 07:21:54 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;
… …
11 11
12 my $hdl; $hdl = new AnyEvent::Handle 12 my $hdl; $hdl = new AnyEvent::Handle
13 fh => \*STDIN, 13 fh => \*STDIN,
14 on_error => sub { 14 on_error => sub {
15 my ($hdl, $fatal, $msg) = @_; 15 my ($hdl, $fatal, $msg) = @_;
16 warn "got error $msg\n"; 16 AE::log 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
25 $hdl->push_read (line => sub { 25 $hdl->push_read (line => sub {
26 my ($hdl, $line) = @_; 26 my ($hdl, $line) = @_;
27 warn "got line <$line>\n"; 27 AE::log warn => "got line <$line>\n";
28 $cv->send; 28 $cv->send;
29 }); 29 });
30 30
31 $cv->recv; 31 $cv->recv;
32 32
33=head1 DESCRIPTION 33=head1 DESCRIPTION
34 34
35This module is a helper module to make it easier to do event-based I/O on 35This is a helper module to make it easier to do event-based I/O on
36filehandles. 36stream-based filehandles (sockets, pipes, and other stream things).
37 37
38The L<AnyEvent::Intro> tutorial contains some well-documented 38The L<AnyEvent::Intro> tutorial contains some well-documented
39AnyEvent::Handle examples. 39AnyEvent::Handle examples.
40 40
41In the following, when the documentation refers to of "bytes" then this 41In the following, where the documentation refers to "bytes", it means
42means characters. As sysread and syswrite are used for all I/O, their 42characters. As sysread and syswrite are used for all I/O, their
43treatment of characters applies to this module as well. 43treatment of characters applies to this module as well.
44 44
45At the very minimum, you should specify C<fh> or C<connect>, and the 45At the very minimum, you should specify C<fh> or C<connect>, and the
46C<on_error> callback. 46C<on_error> callback.
47 47
… …
60use AnyEvent (); BEGIN { AnyEvent::common_sense } 60use AnyEvent (); BEGIN { AnyEvent::common_sense }
61use AnyEvent::Util qw(WSAEWOULDBLOCK); 61use AnyEvent::Util qw(WSAEWOULDBLOCK);
62 62
63our $VERSION = $AnyEvent::VERSION; 63our $VERSION = $AnyEvent::VERSION;
64 64
65sub _load_func($) {
66 my $func = $_[0];
67
68 unless (defined &$func) {
69 my $pkg = $func;
70 do {
71 $pkg =~ s/::[^:]+$//
72 or return;
73 eval "require $pkg";
74 } until defined &$func;
75 }
76
77 \&$func
78}
79
80sub MAX_READ_SIZE() { 131072 }
81
65=head1 METHODS 82=head1 METHODS
66 83
67=over 4 84=over 4
68 85
69=item $handle = B<new> AnyEvent::TLS fh => $filehandle, key => value... 86=item $handle = B<new> AnyEvent::Handle fh => $filehandle, key => value...
70 87
71The constructor supports these arguments (all as C<< key => value >> pairs). 88The constructor supports these arguments (all as C<< key => value >> pairs).
72 89
73=over 4 90=over 4
74 91
… …
97=over 4 114=over 4
98 115
99=item on_prepare => $cb->($handle) 116=item on_prepare => $cb->($handle)
100 117
101This (rarely used) callback is called before a new connection is 118This (rarely used) callback is called before a new connection is
102attempted, but after the file handle has been created. It could be used to 119attempted, but after the file handle has been created (you can access that
120file handle via C<< $handle->{fh} >>). It could be used to prepare the
103prepare the file handle with parameters required for the actual connect 121file handle with parameters required for the actual connect (as opposed to
104(as opposed to settings that can be changed when the connection is already 122settings that can be changed when the connection is already established).
105established).
106 123
107The return value of this callback should be the connect timeout value in 124The return value of this callback should be the connect timeout value in
108seconds (or C<0>, or C<undef>, or the empty list, to indicate the default 125seconds (or C<0>, or C<undef>, or the empty list, to indicate that the
109timeout is to be used). 126default timeout is to be used).
110 127
111=item on_connect => $cb->($handle, $host, $port, $retry->()) 128=item on_connect => $cb->($handle, $host, $port, $retry->())
112 129
113This callback is called when a connection has been successfully established. 130This callback is called when a connection has been successfully established.
114 131
115The actual numeric host and port (the socket peername) are passed as 132The peer's numeric host and port (the socket peername) are passed as
116parameters, together with a retry callback. 133parameters, together with a retry callback.
117 134
118When, for some reason, the handle is not acceptable, then calling 135If, for some reason, the handle is not acceptable, calling C<$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 of each
233of each other, for both read and write, just read, and just write: 253other, for both read and write (triggered when nothing was read I<OR>
254written), just read (triggered when nothing was read), and just write:
234C<timeout>, C<rtimeout> and C<wtimeout>, with corresponding callbacks 255C<timeout>, C<rtimeout> and C<wtimeout>, with corresponding callbacks
235C<on_timeout>, C<on_rtimeout> and C<on_wtimeout>, and reset functions 256C<on_timeout>, C<on_rtimeout> and C<on_wtimeout>, and reset functions
236C<timeout_reset>, C<rtimeout_reset>, and C<wtimeout_reset>. 257C<timeout_reset>, C<rtimeout_reset>, and C<wtimeout_reset>.
237 258
238Note that timeout processing is also active when you currently do not have 259Note that timeout processing is active even when you do not have any
239any outstanding read or write requests: If you plan to keep the connection 260outstanding read or write requests: If you plan to keep the connection
240idle then you should disable the timout temporarily or ignore the timeout 261idle then you should disable the timeout temporarily or ignore the
241in the C<on_timeout> callback, in which case AnyEvent::Handle will simply 262timeout in the corresponding C<on_timeout> callback, in which case
242restart the timeout. 263AnyEvent::Handle will simply restart the timeout.
243 264
244Zero (the default) disables this timeout. 265Zero (the default) disables the corresponding timeout.
245 266
246=item on_timeout => $cb->($handle) 267=item on_timeout => $cb->($handle)
268
269=item on_rtimeout => $cb->($handle)
270
271=item on_wtimeout => $cb->($handle)
247 272
248Called whenever the inactivity timeout passes. If you return from this 273Called whenever the inactivity timeout passes. If you return from this
249callback, then the timeout will be reset as if some activity had happened, 274callback, then the timeout will be reset as if some activity had happened,
250so this condition is not fatal in any way. 275so this condition is not fatal in any way.
251 276
… …
259be configured to accept only so-and-so much data that it cannot act on 284be 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 285(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 286amount of data without a callback ever being called as long as the line
262isn't finished). 287isn't finished).
263 288
289=item wbuf_max => <bytes>
290
291If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)
292when the write buffer ever (strictly) exceeds this size. This is useful to
293avoid some forms of denial-of-service attacks.
294
295Although the units of this parameter is bytes, this is the I<raw> number
296of bytes not yet accepted by the kernel. This can make a difference when
297you e.g. use TLS, as TLS typically makes your write data larger (but it
298can also make it smaller due to compression).
299
300As an example of when this limit is useful, take a chat server that sends
301chat messages to a client. If the client does not read those in a timely
302manner then the send buffer in the server would grow unbounded.
303
264=item autocork => <boolean> 304=item autocork => <boolean>
265 305
266When disabled (the default), then C<push_write> will try to immediately 306When disabled (the default), C<push_write> will try to immediately
267write the data to the handle, if possible. This avoids having to register 307write 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 308a write watcher and wait for the next event loop iteration, but can
269be inefficient if you write multiple small chunks (on the wire, this 309be inefficient if you write multiple small chunks (on the wire, this
270disadvantage is usually avoided by your kernel's nagle algorithm, see 310disadvantage is usually avoided by your kernel's nagle algorithm, see
271C<no_delay>, but this option can save costly syscalls). 311C<no_delay>, but this option can save costly syscalls).
272 312
273When enabled, then writes will always be queued till the next event loop 313When enabled, writes will always be queued till the next event loop
274iteration. This is efficient when you do many small writes per iteration, 314iteration. 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 315but less efficient when you do a single write only per iteration (or when
276the write buffer often is full). It also increases write latency. 316the write buffer often is full). It also increases write latency.
277 317
278=item no_delay => <boolean> 318=item no_delay => <boolean>
… …
282the Nagle algorithm, and usually it is beneficial. 322the Nagle algorithm, and usually it is beneficial.
283 323
284In some situations you want as low a delay as possible, which can be 324In some situations you want as low a delay as possible, which can be
285accomplishd by setting this option to a true value. 325accomplishd by setting this option to a true value.
286 326
287The default is your opertaing system's default behaviour (most likely 327The default is your operating system's default behaviour (most likely
288enabled), this option explicitly enables or disables it, if possible. 328enabled). This option explicitly enables or disables it, if possible.
329
330=item keepalive => <boolean>
331
332Enables (default disable) the SO_KEEPALIVE option on the stream socket:
333normally, TCP connections have no time-out once established, so TCP
334connections, once established, can stay alive forever even when the other
335side has long gone. TCP keepalives are a cheap way to take down long-lived
336TCP connections when the other side becomes unreachable. While the default
337is OS-dependent, TCP keepalives usually kick in after around two hours,
338and, if the other side doesn't reply, take down the TCP connection some 10
339to 15 minutes later.
340
341It is harmless to specify this option for file handles that do not support
342keepalives, and enabling it on connections that are potentially long-lived
343is usually a good idea.
344
345=item oobinline => <boolean>
346
347BSD majorly fucked up the implementation of TCP urgent data. The result
348is that almost no OS implements TCP according to the specs, and every OS
349implements it slightly differently.
350
351If you want to handle TCP urgent data, then setting this flag (the default
352is enabled) gives you the most portable way of getting urgent data, by
353putting it into the stream.
354
355Since BSD emulation of OOB data on top of TCP's urgent data can have
356security implications, AnyEvent::Handle sets this flag automatically
357unless explicitly specified. Note that setting this flag after
358establishing a connection I<may> be a bit too late (data loss could
359already have occured on BSD systems), but at least it will protect you
360from most attacks.
289 361
290=item read_size => <bytes> 362=item read_size => <bytes>
291 363
292The default read block size (the amount of bytes this module will 364The initial read block size, the number of bytes this module will try
293try to read during each loop iteration, which affects memory 365to read during each loop iteration. Each handle object will consume
294requirements). Default: C<8192>. 366at least this amount of memory for the read buffer as well, so when
367handling many connections watch out for memory requirements). See also
368C<max_read_size>. Default: C<2048>.
369
370=item max_read_size => <bytes>
371
372The maximum read buffer size used by the dynamic adjustment
373algorithm: Each time AnyEvent::Handle can read C<read_size> bytes in
374one go it will double C<read_size> up to the maximum given by this
375option. Default: C<131072> or C<read_size>, whichever is higher.
295 376
296=item low_water_mark => <bytes> 377=item low_water_mark => <bytes>
297 378
298Sets the amount of bytes (default: C<0>) that make up an "empty" write 379Sets the number of bytes (default: C<0>) that make up an "empty" write
299buffer: If the write reaches this size or gets even samller it is 380buffer: If the buffer reaches this size or gets even samller it is
300considered empty. 381considered empty.
301 382
302Sometimes it can be beneficial (for performance reasons) to add data to 383Sometimes it can be beneficial (for performance reasons) to add data to
303the write buffer before it is fully drained, but this is a rare case, as 384the write buffer before it is fully drained, but this is a rare case, as
304the operating system kernel usually buffers data as well, so the default 385the operating system kernel usually buffers data as well, so the default
305is good in almost all cases. 386is good in almost all cases.
306 387
307=item linger => <seconds> 388=item linger => <seconds>
308 389
309If non-zero (default: C<3600>), then the destructor of the 390If this is non-zero (default: C<3600>), the destructor of the
310AnyEvent::Handle object will check whether there is still outstanding 391AnyEvent::Handle object will check whether there is still outstanding
311write data and will install a watcher that will write this data to the 392write data and will install a watcher that will write this data to the
312socket. No errors will be reported (this mostly matches how the operating 393socket. No errors will be reported (this mostly matches how the operating
313system treats outstanding data at socket close time). 394system treats outstanding data at socket close time).
314 395
… …
321A string used to identify the remote site - usually the DNS hostname 402A string used to identify the remote site - usually the DNS hostname
322(I<not> IDN!) used to create the connection, rarely the IP address. 403(I<not> IDN!) used to create the connection, rarely the IP address.
323 404
324Apart from being useful in error messages, this string is also used in TLS 405Apart from being useful in error messages, this string is also used in TLS
325peername verification (see C<verify_peername> in L<AnyEvent::TLS>). This 406peername verification (see C<verify_peername> in L<AnyEvent::TLS>). This
326verification will be skipped when C<peername> is not specified or 407verification will be skipped when C<peername> is not specified or is
327C<undef>. 408C<undef>.
328 409
329=item tls => "accept" | "connect" | Net::SSLeay::SSL object 410=item tls => "accept" | "connect" | Net::SSLeay::SSL object
330 411
331When this parameter is given, it enables TLS (SSL) mode, that means 412When this parameter is given, it enables TLS (SSL) mode, that means
332AnyEvent will start a TLS handshake as soon as the conenction has been 413AnyEvent will start a TLS handshake as soon as the connection has been
333established and will transparently encrypt/decrypt data afterwards. 414established and will transparently encrypt/decrypt data afterwards.
334 415
335All TLS protocol errors will be signalled as C<EPROTO>, with an 416All TLS protocol errors will be signalled as C<EPROTO>, with an
336appropriate error message. 417appropriate error message.
337 418
… …
357B<IMPORTANT:> since Net::SSLeay "objects" are really only integers, 438B<IMPORTANT:> since Net::SSLeay "objects" are really only integers,
358passing in the wrong integer will lead to certain crash. This most often 439passing in the wrong integer will lead to certain crash. This most often
359happens when one uses a stylish C<< tls => 1 >> and is surprised about the 440happens when one uses a stylish C<< tls => 1 >> and is surprised about the
360segmentation fault. 441segmentation fault.
361 442
362See the C<< ->starttls >> method for when need to start TLS negotiation later. 443Use the C<< ->starttls >> method if you need to start TLS negotiation later.
363 444
364=item tls_ctx => $anyevent_tls 445=item tls_ctx => $anyevent_tls
365 446
366Use the given C<AnyEvent::TLS> object to create the new TLS connection 447Use the given C<AnyEvent::TLS> object to create the new TLS connection
367(unless a connection object was specified directly). If this parameter is 448(unless a connection object was specified directly). If this
368missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>. 449parameter is missing (or C<undef>), then AnyEvent::Handle will use
450C<AnyEvent::Handle::TLS_CTX>.
369 451
370Instead of an object, you can also specify a hash reference with C<< key 452Instead of an object, you can also specify a hash reference with C<< key
371=> value >> pairs. Those will be passed to L<AnyEvent::TLS> to create a 453=> value >> pairs. Those will be passed to L<AnyEvent::TLS> to create a
372new TLS context object. 454new TLS context object.
373 455
… …
382 464
383TLS handshake failures will not cause C<on_error> to be invoked when this 465TLS handshake failures will not cause C<on_error> to be invoked when this
384callback is in effect, instead, the error message will be passed to C<on_starttls>. 466callback is in effect, instead, the error message will be passed to C<on_starttls>.
385 467
386Without this callback, handshake failures lead to C<on_error> being 468Without this callback, handshake failures lead to C<on_error> being
387called, as normal. 469called as usual.
388 470
389Note that you cannot call C<starttls> right again in this callback. If you 471Note that you cannot just call C<starttls> again in this callback. If you
390need to do that, start an zero-second timer instead whose callback can 472need to do that, start an zero-second timer instead whose callback can
391then call C<< ->starttls >> again. 473then call C<< ->starttls >> again.
392 474
393=item on_stoptls => $cb->($handle) 475=item on_stoptls => $cb->($handle)
394 476
… …
442 $self->{connect}[0], 524 $self->{connect}[0],
443 $self->{connect}[1], 525 $self->{connect}[1],
444 sub { 526 sub {
445 my ($fh, $host, $port, $retry) = @_; 527 my ($fh, $host, $port, $retry) = @_;
446 528
529 delete $self->{_connect}; # no longer needed
530
447 if ($fh) { 531 if ($fh) {
448 $self->{fh} = $fh; 532 $self->{fh} = $fh;
449 533
450 delete $self->{_skip_drain_rbuf}; 534 delete $self->{_skip_drain_rbuf};
451 $self->_start; 535 $self->_start;
… …
458 }); 542 });
459 543
460 } else { 544 } else {
461 if ($self->{on_connect_error}) { 545 if ($self->{on_connect_error}) {
462 $self->{on_connect_error}($self, "$!"); 546 $self->{on_connect_error}($self, "$!");
463 $self->destroy; 547 $self->destroy if $self;
464 } else { 548 } else {
465 $self->_error ($!, 1); 549 $self->_error ($!, 1);
466 } 550 }
467 } 551 }
468 }, 552 },
469 sub { 553 sub {
470 local $self->{fh} = $_[0]; 554 local $self->{fh} = $_[0];
471 555
472 $self->{on_prepare} 556 $self->{on_prepare}
473 ? $self->{on_prepare}->($self) 557 ? $self->{on_prepare}->($self)
474 : () 558 : ()
475 } 559 }
476 ); 560 );
477 } 561 }
478 562
… …
484} 568}
485 569
486sub _start { 570sub _start {
487 my ($self) = @_; 571 my ($self) = @_;
488 572
573 # too many clueless people try to use udp and similar sockets
574 # with AnyEvent::Handle, do them a favour.
575 my $type = getsockopt $self->{fh}, Socket::SOL_SOCKET (), Socket::SO_TYPE ();
576 Carp::croak "AnyEvent::Handle: only stream sockets supported, anything else will NOT work!"
577 if Socket::SOCK_STREAM () != (unpack "I", $type) && defined $type;
578
489 AnyEvent::Util::fh_nonblocking $self->{fh}, 1; 579 AnyEvent::Util::fh_nonblocking $self->{fh}, 1;
490 580
491 $self->{_activity} = 581 $self->{_activity} =
492 $self->{_ractivity} = 582 $self->{_ractivity} =
493 $self->{_wactivity} = AE::now; 583 $self->{_wactivity} = AE::now;
494 584
585 $self->{read_size} ||= 2048;
586 $self->{max_read_size} = $self->{read_size}
587 if $self->{read_size} > ($self->{max_read_size} || MAX_READ_SIZE);
588
495 $self->timeout (delete $self->{timeout} ) if $self->{timeout}; 589 $self->timeout (delete $self->{timeout} ) if $self->{timeout};
496 $self->rtimeout (delete $self->{rtimeout}) if $self->{rtimeout}; 590 $self->rtimeout (delete $self->{rtimeout} ) if $self->{rtimeout};
497 $self->wtimeout (delete $self->{wtimeout}) if $self->{wtimeout}; 591 $self->wtimeout (delete $self->{wtimeout} ) if $self->{wtimeout};
498 592
499 $self->no_delay (delete $self->{no_delay}) if exists $self->{no_delay}; 593 $self->no_delay (delete $self->{no_delay} ) if exists $self->{no_delay} && $self->{no_delay};
594 $self->keepalive (delete $self->{keepalive}) if exists $self->{keepalive} && $self->{keepalive};
500 595
596 $self->oobinline (exists $self->{oobinline} ? delete $self->{oobinline} : 1);
597
501 $self->starttls (delete $self->{tls}, delete $self->{tls_ctx}) 598 $self->starttls (delete $self->{tls}, delete $self->{tls_ctx})
502 if $self->{tls}; 599 if $self->{tls};
503 600
504 $self->on_drain (delete $self->{on_drain}) if $self->{on_drain}; 601 $self->on_drain (delete $self->{on_drain} ) if $self->{on_drain};
505 602
506 $self->start_read 603 $self->start_read
507 if $self->{on_read} || @{ $self->{_queue} }; 604 if $self->{on_read} || @{ $self->{_queue} };
508 605
509 $self->_drain_wbuf; 606 $self->_drain_wbuf;
… …
516 $message ||= "$!"; 613 $message ||= "$!";
517 614
518 if ($self->{on_error}) { 615 if ($self->{on_error}) {
519 $self->{on_error}($self, $fatal, $message); 616 $self->{on_error}($self, $fatal, $message);
520 $self->destroy if $fatal; 617 $self->destroy if $fatal;
521 } elsif ($self->{fh}) { 618 } elsif ($self->{fh} || $self->{connect}) {
522 $self->destroy; 619 $self->destroy;
523 Carp::croak "AnyEvent::Handle uncaught error: $message"; 620 Carp::croak "AnyEvent::Handle uncaught error: $message";
524 } 621 }
525} 622}
526 623
… …
585=cut 682=cut
586 683
587sub no_delay { 684sub no_delay {
588 $_[0]{no_delay} = $_[1]; 685 $_[0]{no_delay} = $_[1];
589 686
687 setsockopt $_[0]{fh}, Socket::IPPROTO_TCP (), Socket::TCP_NODELAY (), int $_[1]
688 if $_[0]{fh};
689}
690
691=item $handle->keepalive ($boolean)
692
693Enables or disables the C<keepalive> setting (see constructor argument of
694the same name for details).
695
696=cut
697
698sub keepalive {
699 $_[0]{keepalive} = $_[1];
700
590 eval { 701 eval {
591 local $SIG{__DIE__}; 702 local $SIG{__DIE__};
592 setsockopt $_[0]{fh}, &Socket::IPPROTO_TCP, &Socket::TCP_NODELAY, int $_[1] 703 setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_KEEPALIVE (), int $_[1]
593 if $_[0]{fh}; 704 if $_[0]{fh};
594 }; 705 };
595} 706}
596 707
708=item $handle->oobinline ($boolean)
709
710Enables or disables the C<oobinline> setting (see constructor argument of
711the same name for details).
712
713=cut
714
715sub oobinline {
716 $_[0]{oobinline} = $_[1];
717
718 eval {
719 local $SIG{__DIE__};
720 setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_OOBINLINE (), int $_[1]
721 if $_[0]{fh};
722 };
723}
724
725=item $handle->keepalive ($boolean)
726
727Enables or disables the C<keepalive> setting (see constructor argument of
728the same name for details).
729
730=cut
731
732sub keepalive {
733 $_[0]{keepalive} = $_[1];
734
735 eval {
736 local $SIG{__DIE__};
737 setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_KEEPALIVE (), int $_[1]
738 if $_[0]{fh};
739 };
740}
741
597=item $handle->on_starttls ($cb) 742=item $handle->on_starttls ($cb)
598 743
599Replace the current C<on_starttls> callback (see the C<on_starttls> constructor argument). 744Replace the current C<on_starttls> callback (see the C<on_starttls> constructor argument).
600 745
601=cut 746=cut
… …
608 753
609Replace the current C<on_stoptls> callback (see the C<on_stoptls> constructor argument). 754Replace the current C<on_stoptls> callback (see the C<on_stoptls> constructor argument).
610 755
611=cut 756=cut
612 757
613sub on_starttls { 758sub on_stoptls {
614 $_[0]{on_stoptls} = $_[1]; 759 $_[0]{on_stoptls} = $_[1];
615} 760}
616 761
617=item $handle->rbuf_max ($max_octets) 762=item $handle->rbuf_max ($max_octets)
618 763
619Configures the C<rbuf_max> setting (C<undef> disables it). 764Configures the C<rbuf_max> setting (C<undef> disables it).
765
766=item $handle->wbuf_max ($max_octets)
767
768Configures the C<wbuf_max> setting (C<undef> disables it).
620 769
621=cut 770=cut
622 771
623sub rbuf_max { 772sub rbuf_max {
624 $_[0]{rbuf_max} = $_[1]; 773 $_[0]{rbuf_max} = $_[1];
625} 774}
626 775
776sub wbuf_max {
777 $_[0]{wbuf_max} = $_[1];
778}
779
627############################################################################# 780#############################################################################
628 781
629=item $handle->timeout ($seconds) 782=item $handle->timeout ($seconds)
630 783
631=item $handle->rtimeout ($seconds) 784=item $handle->rtimeout ($seconds)
632 785
633=item $handle->wtimeout ($seconds) 786=item $handle->wtimeout ($seconds)
634 787
635Configures (or disables) the inactivity timeout. 788Configures (or disables) the inactivity timeout.
789
790The timeout will be checked instantly, so this method might destroy the
791handle before it returns.
636 792
637=item $handle->timeout_reset 793=item $handle->timeout_reset
638 794
639=item $handle->rtimeout_reset 795=item $handle->rtimeout_reset
640 796
… …
657 $_[0]{$on_timeout} = $_[1]; 813 $_[0]{$on_timeout} = $_[1];
658 }; 814 };
659 815
660 *$timeout = sub { 816 *$timeout = sub {
661 my ($self, $new_value) = @_; 817 my ($self, $new_value) = @_;
818
819 $new_value >= 0
820 or Carp::croak "AnyEvent::Handle->$timeout called with negative timeout ($new_value), caught";
662 821
663 $self->{$timeout} = $new_value; 822 $self->{$timeout} = $new_value;
664 delete $self->{$tw}; &$cb; 823 delete $self->{$tw}; &$cb;
665 }; 824 };
666 825
… …
730=item $handle->on_drain ($cb) 889=item $handle->on_drain ($cb)
731 890
732Sets the C<on_drain> callback or clears it (see the description of 891Sets the C<on_drain> callback or clears it (see the description of
733C<on_drain> in the constructor). 892C<on_drain> in the constructor).
734 893
894This method may invoke callbacks (and therefore the handle might be
895destroyed after it returns).
896
735=cut 897=cut
736 898
737sub on_drain { 899sub on_drain {
738 my ($self, $cb) = @_; 900 my ($self, $cb) = @_;
739 901
… …
743 if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf}); 905 if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf});
744} 906}
745 907
746=item $handle->push_write ($data) 908=item $handle->push_write ($data)
747 909
748Queues the given scalar to be written. You can push as much data as you 910Queues the given scalar to be written. You can push as much data as
749want (only limited by the available memory), as C<AnyEvent::Handle> 911you want (only limited by the available memory and C<wbuf_max>), as
750buffers it independently of the kernel. 912C<AnyEvent::Handle> buffers it independently of the kernel.
913
914This method may invoke callbacks (and therefore the handle might be
915destroyed after it returns).
751 916
752=cut 917=cut
753 918
754sub _drain_wbuf { 919sub _drain_wbuf {
755 my ($self) = @_; 920 my ($self) = @_;
… …
780 $cb->() unless $self->{autocork}; 945 $cb->() unless $self->{autocork};
781 946
782 # if still data left in wbuf, we need to poll 947 # if still data left in wbuf, we need to poll
783 $self->{_ww} = AE::io $self->{fh}, 1, $cb 948 $self->{_ww} = AE::io $self->{fh}, 1, $cb
784 if length $self->{wbuf}; 949 if length $self->{wbuf};
950
951 if (
952 defined $self->{wbuf_max}
953 && $self->{wbuf_max} < length $self->{wbuf}
954 ) {
955 $self->_error (Errno::ENOSPC, 1), return;
956 }
785 }; 957 };
786} 958}
787 959
788our %WH; 960our %WH;
789 961
962# deprecated
790sub register_write_type($$) { 963sub register_write_type($$) {
791 $WH{$_[0]} = $_[1]; 964 $WH{$_[0]} = $_[1];
792} 965}
793 966
794sub push_write { 967sub push_write {
795 my $self = shift; 968 my $self = shift;
796 969
797 if (@_ > 1) { 970 if (@_ > 1) {
798 my $type = shift; 971 my $type = shift;
799 972
973 @_ = ($WH{$type} ||= _load_func "$type\::anyevent_write_type"
800 @_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write") 974 or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::push_write")
801 ->($self, @_); 975 ->($self, @_);
802 } 976 }
803 977
978 # we downgrade here to avoid hard-to-track-down bugs,
979 # and diagnose the problem earlier and better.
980
804 if ($self->{tls}) { 981 if ($self->{tls}) {
805 $self->{_tls_wbuf} .= $_[0]; 982 utf8::downgrade $self->{_tls_wbuf} .= $_[0];
806 &_dotls ($self) if $self->{fh}; 983 &_dotls ($self) if $self->{fh};
807 } else { 984 } else {
808 $self->{wbuf} .= $_[0]; 985 utf8::downgrade $self->{wbuf} .= $_[0];
809 $self->_drain_wbuf if $self->{fh}; 986 $self->_drain_wbuf if $self->{fh};
810 } 987 }
811} 988}
812 989
813=item $handle->push_write (type => @args) 990=item $handle->push_write (type => @args)
814 991
815Instead of formatting your data yourself, you can also let this module do 992Instead of formatting your data yourself, you can also let this module
816the job by specifying a type and type-specific arguments. 993do the job by specifying a type and type-specific arguments. You
994can also specify the (fully qualified) name of a package, in which
995case AnyEvent tries to load the package and then expects to find the
996C<anyevent_write_type> function inside (see "custom write types", below).
817 997
818Predefined types are (if you have ideas for additional types, feel free to 998Predefined types are (if you have ideas for additional types, feel free to
819drop by and tell us): 999drop by and tell us):
820 1000
821=over 4 1001=over 4
… …
878Other languages could read single lines terminated by a newline and pass 1058Other languages could read single lines terminated by a newline and pass
879this line into their JSON decoder of choice. 1059this line into their JSON decoder of choice.
880 1060
881=cut 1061=cut
882 1062
1063sub json_coder() {
1064 eval { require JSON::XS; JSON::XS->new->utf8 }
1065 || do { require JSON; JSON->new->utf8 }
1066}
1067
883register_write_type json => sub { 1068register_write_type json => sub {
884 my ($self, $ref) = @_; 1069 my ($self, $ref) = @_;
885 1070
886 require JSON; 1071 my $json = $self->{json} ||= json_coder;
887 1072
888 $self->{json} ? $self->{json}->encode ($ref) 1073 $json->encode ($ref)
889 : JSON::encode_json ($ref)
890}; 1074};
891 1075
892=item storable => $reference 1076=item storable => $reference
893 1077
894Freezes the given reference using L<Storable> and writes it to the 1078Freezes the given reference using L<Storable> and writes it to the
… …
897=cut 1081=cut
898 1082
899register_write_type storable => sub { 1083register_write_type storable => sub {
900 my ($self, $ref) = @_; 1084 my ($self, $ref) = @_;
901 1085
902 require Storable; 1086 require Storable unless $Storable::VERSION;
903 1087
904 pack "w/a*", Storable::nfreeze ($ref) 1088 pack "w/a*", Storable::nfreeze ($ref)
905}; 1089};
906 1090
907=back 1091=back
… …
912before it was actually written. One way to do that is to replace your 1096before it was actually written. One way to do that is to replace your
913C<on_drain> handler by a callback that shuts down the socket (and set 1097C<on_drain> handler by a callback that shuts down the socket (and set
914C<low_water_mark> to C<0>). This method is a shorthand for just that, and 1098C<low_water_mark> to C<0>). This method is a shorthand for just that, and
915replaces the C<on_drain> callback with: 1099replaces the C<on_drain> callback with:
916 1100
917 sub { shutdown $_[0]{fh}, 1 } # for push_shutdown 1101 sub { shutdown $_[0]{fh}, 1 }
918 1102
919This simply shuts down the write side and signals an EOF condition to the 1103This simply shuts down the write side and signals an EOF condition to the
920the peer. 1104the peer.
921 1105
922You can rely on the normal read queue and C<on_eof> handling 1106You can rely on the normal read queue and C<on_eof> handling
923afterwards. This is the cleanest way to close a connection. 1107afterwards. This is the cleanest way to close a connection.
924 1108
1109This method may invoke callbacks (and therefore the handle might be
1110destroyed after it returns).
1111
925=cut 1112=cut
926 1113
927sub push_shutdown { 1114sub push_shutdown {
928 my ($self) = @_; 1115 my ($self) = @_;
929 1116
930 delete $self->{low_water_mark}; 1117 delete $self->{low_water_mark};
931 $self->on_drain (sub { shutdown $_[0]{fh}, 1 }); 1118 $self->on_drain (sub { shutdown $_[0]{fh}, 1 });
932} 1119}
933 1120
934=item AnyEvent::Handle::register_write_type type => $coderef->($handle, @args) 1121=item custom write types - Package::anyevent_write_type $handle, @args
935 1122
936This function (not method) lets you add your own types to C<push_write>. 1123Instead of one of the predefined types, you can also specify the name of
1124a package. AnyEvent will try to load the package and then expects to find
1125a function named C<anyevent_write_type> inside. If it isn't found, it
1126progressively tries to load the parent package until it either finds the
1127function (good) or runs out of packages (bad).
1128
937Whenever the given C<type> is used, C<push_write> will invoke the code 1129Whenever the given C<type> is used, C<push_write> will the function with
938reference with the handle object and the remaining arguments. 1130the handle object and the remaining arguments.
939 1131
940The code reference is supposed to return a single octet string that will 1132The function is supposed to return a single octet string that will be
941be appended to the write buffer. 1133appended to the write buffer, so you can mentally treat this function as a
1134"arguments to on-the-wire-format" converter.
942 1135
943Note that this is a function, and all types registered this way will be 1136Example: implement a custom write type C<join> that joins the remaining
944global, so try to use unique names. 1137arguments using the first one.
1138
1139 $handle->push_write (My::Type => " ", 1,2,3);
1140
1141 # uses the following package, which can be defined in the "My::Type" or in
1142 # the "My" modules to be auto-loaded, or just about anywhere when the
1143 # My::Type::anyevent_write_type is defined before invoking it.
1144
1145 package My::Type;
1146
1147 sub anyevent_write_type {
1148 my ($handle, $delim, @args) = @_;
1149
1150 join $delim, @args
1151 }
945 1152
946=cut 1153=cut
947 1154
948############################################################################# 1155#############################################################################
949 1156
… …
958ways, the "simple" way, using only C<on_read> and the "complex" way, using 1165ways, the "simple" way, using only C<on_read> and the "complex" way, using
959a queue. 1166a queue.
960 1167
961In the simple case, you just install an C<on_read> callback and whenever 1168In the simple case, you just install an C<on_read> callback and whenever
962new data arrives, it will be called. You can then remove some data (if 1169new data arrives, it will be called. You can then remove some data (if
963enough is there) from the read buffer (C<< $handle->rbuf >>). Or you cna 1170enough is there) from the read buffer (C<< $handle->rbuf >>). Or you can
964leave the data there if you want to accumulate more (e.g. when only a 1171leave the data there if you want to accumulate more (e.g. when only a
965partial message has been received so far). 1172partial message has been received so far), or change the read queue with
1173e.g. C<push_read>.
966 1174
967In the more complex case, you want to queue multiple callbacks. In this 1175In the more complex case, you want to queue multiple callbacks. In this
968case, AnyEvent::Handle will call the first queued callback each time new 1176case, AnyEvent::Handle will call the first queued callback each time new
969data arrives (also the first time it is queued) and removes it when it has 1177data arrives (also the first time it is queued) and remove it when it has
970done its job (see C<push_read>, below). 1178done its job (see C<push_read>, below).
971 1179
972This way you can, for example, push three line-reads, followed by reading 1180This way you can, for example, push three line-reads, followed by reading
973a chunk of data, and AnyEvent::Handle will execute them in order. 1181a chunk of data, and AnyEvent::Handle will execute them in order.
974 1182
… …
1105 1313
1106This replaces the currently set C<on_read> callback, or clears it (when 1314This replaces the currently set C<on_read> callback, or clears it (when
1107the new callback is C<undef>). See the description of C<on_read> in the 1315the new callback is C<undef>). See the description of C<on_read> in the
1108constructor. 1316constructor.
1109 1317
1318This method may invoke callbacks (and therefore the handle might be
1319destroyed after it returns).
1320
1110=cut 1321=cut
1111 1322
1112sub on_read { 1323sub on_read {
1113 my ($self, $cb) = @_; 1324 my ($self, $cb) = @_;
1114 1325
… …
1116 $self->_drain_rbuf if $cb; 1327 $self->_drain_rbuf if $cb;
1117} 1328}
1118 1329
1119=item $handle->rbuf 1330=item $handle->rbuf
1120 1331
1121Returns the read buffer (as a modifiable lvalue). 1332Returns the read buffer (as a modifiable lvalue). You can also access the
1333read buffer directly as the C<< ->{rbuf} >> member, if you want (this is
1334much faster, and no less clean).
1122 1335
1123You can access the read buffer directly as the C<< ->{rbuf} >> 1336The only operation allowed on the read buffer (apart from looking at it)
1124member, if you want. However, the only operation allowed on the 1337is removing data from its beginning. Otherwise modifying or appending to
1125read buffer (apart from looking at it) is removing data from its 1338it is not allowed and will lead to hard-to-track-down bugs.
1126beginning. Otherwise modifying or appending to it is not allowed and will
1127lead to hard-to-track-down bugs.
1128 1339
1129NOTE: The read buffer should only be used or modified if the C<on_read>, 1340NOTE: The read buffer should only be used or modified in the C<on_read>
1130C<push_read> or C<unshift_read> methods are used. The other read methods 1341callback or when C<push_read> or C<unshift_read> are used with a single
1131automatically manage the read buffer. 1342callback (i.e. untyped). Typed C<push_read> and C<unshift_read> methods
1343will manage the read buffer on their own.
1132 1344
1133=cut 1345=cut
1134 1346
1135sub rbuf : lvalue { 1347sub rbuf : lvalue {
1136 $_[0]{rbuf} 1348 $_[0]{rbuf}
… …
1153 1365
1154If enough data was available, then the callback must remove all data it is 1366If enough data was available, then the callback must remove all data it is
1155interested in (which can be none at all) and return a true value. After returning 1367interested in (which can be none at all) and return a true value. After returning
1156true, it will be removed from the queue. 1368true, it will be removed from the queue.
1157 1369
1370These methods may invoke callbacks (and therefore the handle might be
1371destroyed after it returns).
1372
1158=cut 1373=cut
1159 1374
1160our %RH; 1375our %RH;
1161 1376
1162sub register_read_type($$) { 1377sub register_read_type($$) {
… …
1168 my $cb = pop; 1383 my $cb = pop;
1169 1384
1170 if (@_) { 1385 if (@_) {
1171 my $type = shift; 1386 my $type = shift;
1172 1387
1388 $cb = ($RH{$type} ||= _load_func "$type\::anyevent_read_type"
1173 $cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_read") 1389 or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::push_read")
1174 ->($self, $cb, @_); 1390 ->($self, $cb, @_);
1175 } 1391 }
1176 1392
1177 push @{ $self->{_queue} }, $cb; 1393 push @{ $self->{_queue} }, $cb;
1178 $self->_drain_rbuf; 1394 $self->_drain_rbuf;
… …
1183 my $cb = pop; 1399 my $cb = pop;
1184 1400
1185 if (@_) { 1401 if (@_) {
1186 my $type = shift; 1402 my $type = shift;
1187 1403
1404 $cb = ($RH{$type} ||= _load_func "$type\::anyevent_read_type"
1188 $cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::unshift_read") 1405 or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::unshift_read")
1189 ->($self, $cb, @_); 1406 ->($self, $cb, @_);
1190 } 1407 }
1191
1192 1408
1193 unshift @{ $self->{_queue} }, $cb; 1409 unshift @{ $self->{_queue} }, $cb;
1194 $self->_drain_rbuf; 1410 $self->_drain_rbuf;
1195} 1411}
1196 1412
… …
1198 1414
1199=item $handle->unshift_read (type => @args, $cb) 1415=item $handle->unshift_read (type => @args, $cb)
1200 1416
1201Instead of providing a callback that parses the data itself you can chose 1417Instead of providing a callback that parses the data itself you can chose
1202between a number of predefined parsing formats, for chunks of data, lines 1418between a number of predefined parsing formats, for chunks of data, lines
1203etc. 1419etc. You can also specify the (fully qualified) name of a package, in
1420which case AnyEvent tries to load the package and then expects to find the
1421C<anyevent_read_type> function inside (see "custom read types", below).
1204 1422
1205Predefined types are (if you have ideas for additional types, feel free to 1423Predefined types are (if you have ideas for additional types, feel free to
1206drop by and tell us): 1424drop by and tell us):
1207 1425
1208=over 4 1426=over 4
… …
1214data. 1432data.
1215 1433
1216Example: read 2 bytes. 1434Example: read 2 bytes.
1217 1435
1218 $handle->push_read (chunk => 2, sub { 1436 $handle->push_read (chunk => 2, sub {
1219 warn "yay ", unpack "H*", $_[1]; 1437 AE::log debug => "yay " . unpack "H*", $_[1];
1220 }); 1438 });
1221 1439
1222=cut 1440=cut
1223 1441
1224register_read_type chunk => sub { 1442register_read_type chunk => sub {
… …
1300the receive buffer when neither C<$accept> nor C<$reject> match, 1518the receive buffer when neither C<$accept> nor C<$reject> match,
1301and everything preceding and including the match will be accepted 1519and everything preceding and including the match will be accepted
1302unconditionally. This is useful to skip large amounts of data that you 1520unconditionally. This is useful to skip large amounts of data that you
1303know cannot be matched, so that the C<$accept> or C<$reject> regex do not 1521know cannot be matched, so that the C<$accept> or C<$reject> regex do not
1304have to start matching from the beginning. This is purely an optimisation 1522have to start matching from the beginning. This is purely an optimisation
1305and is usually worth only when you expect more than a few kilobytes. 1523and is usually worth it only when you expect more than a few kilobytes.
1306 1524
1307Example: expect a http header, which ends at C<\015\012\015\012>. Since we 1525Example: expect a http header, which ends at C<\015\012\015\012>. Since we
1308expect the header to be very large (it isn't in practise, but...), we use 1526expect the header to be very large (it isn't in practice, but...), we use
1309a skip regex to skip initial portions. The skip regex is tricky in that 1527a skip regex to skip initial portions. The skip regex is tricky in that
1310it only accepts something not ending in either \015 or \012, as these are 1528it only accepts something not ending in either \015 or \012, as these are
1311required for the accept regex. 1529required for the accept regex.
1312 1530
1313 $handle->push_read (regex => 1531 $handle->push_read (regex =>
… …
1326 1544
1327 sub { 1545 sub {
1328 # accept 1546 # accept
1329 if ($$rbuf =~ $accept) { 1547 if ($$rbuf =~ $accept) {
1330 $data .= substr $$rbuf, 0, $+[0], ""; 1548 $data .= substr $$rbuf, 0, $+[0], "";
1331 $cb->($self, $data); 1549 $cb->($_[0], $data);
1332 return 1; 1550 return 1;
1333 } 1551 }
1334 1552
1335 # reject 1553 # reject
1336 if ($reject && $$rbuf =~ $reject) { 1554 if ($reject && $$rbuf =~ $reject) {
1337 $self->_error (Errno::EBADMSG); 1555 $_[0]->_error (Errno::EBADMSG);
1338 } 1556 }
1339 1557
1340 # skip 1558 # skip
1341 if ($skip && $$rbuf =~ $skip) { 1559 if ($skip && $$rbuf =~ $skip) {
1342 $data .= substr $$rbuf, 0, $+[0], ""; 1560 $data .= substr $$rbuf, 0, $+[0], "";
… …
1358 my ($self, $cb) = @_; 1576 my ($self, $cb) = @_;
1359 1577
1360 sub { 1578 sub {
1361 unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) { 1579 unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
1362 if ($_[0]{rbuf} =~ /[^0-9]/) { 1580 if ($_[0]{rbuf} =~ /[^0-9]/) {
1363 $self->_error (Errno::EBADMSG); 1581 $_[0]->_error (Errno::EBADMSG);
1364 } 1582 }
1365 return; 1583 return;
1366 } 1584 }
1367 1585
1368 my $len = $1; 1586 my $len = $1;
1369 1587
1370 $self->unshift_read (chunk => $len, sub { 1588 $_[0]->unshift_read (chunk => $len, sub {
1371 my $string = $_[1]; 1589 my $string = $_[1];
1372 $_[0]->unshift_read (chunk => 1, sub { 1590 $_[0]->unshift_read (chunk => 1, sub {
1373 if ($_[1] eq ",") { 1591 if ($_[1] eq ",") {
1374 $cb->($_[0], $string); 1592 $cb->($_[0], $string);
1375 } else { 1593 } else {
1376 $self->_error (Errno::EBADMSG); 1594 $_[0]->_error (Errno::EBADMSG);
1377 } 1595 }
1378 }); 1596 });
1379 }); 1597 });
1380 1598
1381 1 1599 1
… …
1448=cut 1666=cut
1449 1667
1450register_read_type json => sub { 1668register_read_type json => sub {
1451 my ($self, $cb) = @_; 1669 my ($self, $cb) = @_;
1452 1670
1453 my $json = $self->{json} ||= 1671 my $json = $self->{json} ||= json_coder;
1454 eval { require JSON::XS; JSON::XS->new->utf8 }
1455 || do { require JSON; JSON->new->utf8 };
1456 1672
1457 my $data; 1673 my $data;
1458 my $rbuf = \$self->{rbuf}; 1674 my $rbuf = \$self->{rbuf};
1459 1675
1460 sub { 1676 sub {
1461 my $ref = eval { $json->incr_parse ($self->{rbuf}) }; 1677 my $ref = eval { $json->incr_parse ($_[0]{rbuf}) };
1462 1678
1463 if ($ref) { 1679 if ($ref) {
1464 $self->{rbuf} = $json->incr_text; 1680 $_[0]{rbuf} = $json->incr_text;
1465 $json->incr_text = ""; 1681 $json->incr_text = "";
1466 $cb->($self, $ref); 1682 $cb->($_[0], $ref);
1467 1683
1468 1 1684 1
1469 } elsif ($@) { 1685 } elsif ($@) {
1470 # error case 1686 # error case
1471 $json->incr_skip; 1687 $json->incr_skip;
1472 1688
1473 $self->{rbuf} = $json->incr_text; 1689 $_[0]{rbuf} = $json->incr_text;
1474 $json->incr_text = ""; 1690 $json->incr_text = "";
1475 1691
1476 $self->_error (Errno::EBADMSG); 1692 $_[0]->_error (Errno::EBADMSG);
1477 1693
1478 () 1694 ()
1479 } else { 1695 } else {
1480 $self->{rbuf} = ""; 1696 $_[0]{rbuf} = "";
1481 1697
1482 () 1698 ()
1483 } 1699 }
1484 } 1700 }
1485}; 1701};
… …
1495=cut 1711=cut
1496 1712
1497register_read_type storable => sub { 1713register_read_type storable => sub {
1498 my ($self, $cb) = @_; 1714 my ($self, $cb) = @_;
1499 1715
1500 require Storable; 1716 require Storable unless $Storable::VERSION;
1501 1717
1502 sub { 1718 sub {
1503 # when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method 1719 # when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
1504 defined (my $len = eval { unpack "w", $_[0]{rbuf} }) 1720 defined (my $len = eval { unpack "w", $_[0]{rbuf} })
1505 or return; 1721 or return;
… …
1518 # read remaining chunk 1734 # read remaining chunk
1519 $_[0]->unshift_read (chunk => $len, sub { 1735 $_[0]->unshift_read (chunk => $len, sub {
1520 if (my $ref = eval { Storable::thaw ($_[1]) }) { 1736 if (my $ref = eval { Storable::thaw ($_[1]) }) {
1521 $cb->($_[0], $ref); 1737 $cb->($_[0], $ref);
1522 } else { 1738 } else {
1523 $self->_error (Errno::EBADMSG); 1739 $_[0]->_error (Errno::EBADMSG);
1524 } 1740 }
1525 }); 1741 });
1526 } 1742 }
1527 1743
1528 1 1744 1
1529 } 1745 }
1530}; 1746};
1531 1747
1532=back 1748=back
1533 1749
1534=item AnyEvent::Handle::register_read_type type => $coderef->($handle, $cb, @args) 1750=item custom read types - Package::anyevent_read_type $handle, $cb, @args
1535 1751
1536This function (not method) lets you add your own types to C<push_read>. 1752Instead of one of the predefined types, you can also specify the name
1753of a package. AnyEvent will try to load the package and then expects to
1754find a function named C<anyevent_read_type> inside. If it isn't found, it
1755progressively tries to load the parent package until it either finds the
1756function (good) or runs out of packages (bad).
1537 1757
1538Whenever the given C<type> is used, C<push_read> will invoke the code 1758Whenever this type is used, C<push_read> will invoke the function with the
1539reference with the handle object, the callback and the remaining 1759handle object, the original callback and the remaining arguments.
1540arguments.
1541 1760
1542The code reference is supposed to return a callback (usually a closure) 1761The function is supposed to return a callback (usually a closure) that
1543that works as a plain read callback (see C<< ->push_read ($cb) >>). 1762works as a plain read callback (see C<< ->push_read ($cb) >>), so you can
1763mentally treat the function as a "configurable read type to read callback"
1764converter.
1544 1765
1545It should invoke the passed callback when it is done reading (remember to 1766It should invoke the original callback when it is done reading (remember
1546pass C<$handle> as first argument as all other callbacks do that). 1767to pass C<$handle> as first argument as all other callbacks do that,
1768although there is no strict requirement on this).
1547 1769
1548Note that this is a function, and all types registered this way will be
1549global, so try to use unique names.
1550
1551For examples, see the source of this module (F<perldoc -m AnyEvent::Handle>, 1770For examples, see the source of this module (F<perldoc -m
1552search for C<register_read_type>)). 1771AnyEvent::Handle>, search for C<register_read_type>)).
1553 1772
1554=item $handle->stop_read 1773=item $handle->stop_read
1555 1774
1556=item $handle->start_read 1775=item $handle->start_read
1557 1776
… …
1563Note that AnyEvent::Handle will automatically C<start_read> for you when 1782Note that AnyEvent::Handle will automatically C<start_read> for you when
1564you change the C<on_read> callback or push/unshift a read callback, and it 1783you change the C<on_read> callback or push/unshift a read callback, and it
1565will automatically C<stop_read> for you when neither C<on_read> is set nor 1784will automatically C<stop_read> for you when neither C<on_read> is set nor
1566there are any read requests in the queue. 1785there are any read requests in the queue.
1567 1786
1568These methods will have no effect when in TLS mode (as TLS doesn't support 1787In older versions of this module (<= 5.3), these methods had no effect,
1569half-duplex connections). 1788as TLS does not support half-duplex connections. In current versions they
1789work as expected, as this behaviour is required to avoid certain resource
1790attacks, where the program would be forced to read (and buffer) arbitrary
1791amounts of data before being able to send some data. The drawback is that
1792some readings of the the SSL/TLS specifications basically require this
1793attack to be working, as SSL/TLS implementations might stall sending data
1794during a rehandshake.
1795
1796As a guideline, during the initial handshake, you should not stop reading,
1797and as a client, it might cause problems, depending on your applciation.
1570 1798
1571=cut 1799=cut
1572 1800
1573sub stop_read { 1801sub stop_read {
1574 my ($self) = @_; 1802 my ($self) = @_;
1575 1803
1576 delete $self->{_rw} unless $self->{tls}; 1804 delete $self->{_rw};
1577} 1805}
1578 1806
1579sub start_read { 1807sub start_read {
1580 my ($self) = @_; 1808 my ($self) = @_;
1581 1809
1582 unless ($self->{_rw} || $self->{_eof}) { 1810 unless ($self->{_rw} || $self->{_eof} || !$self->{fh}) {
1583 Scalar::Util::weaken $self; 1811 Scalar::Util::weaken $self;
1584 1812
1585 $self->{_rw} = AE::io $self->{fh}, 0, sub { 1813 $self->{_rw} = AE::io $self->{fh}, 0, sub {
1586 my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf}); 1814 my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf});
1587 my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf; 1815 my $len = sysread $self->{fh}, $$rbuf, $self->{read_size}, length $$rbuf;
1588 1816
1589 if ($len > 0) { 1817 if ($len > 0) {
1590 $self->{_activity} = $self->{_ractivity} = AE::now; 1818 $self->{_activity} = $self->{_ractivity} = AE::now;
1591 1819
1592 if ($self->{tls}) { 1820 if ($self->{tls}) {
1593 Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf); 1821 Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf);
1594 1822
1595 &_dotls ($self); 1823 &_dotls ($self);
1596 } else { 1824 } else {
1597 $self->_drain_rbuf; 1825 $self->_drain_rbuf;
1826 }
1827
1828 if ($len == $self->{read_size}) {
1829 $self->{read_size} *= 2;
1830 $self->{read_size} = $self->{max_read_size} || MAX_READ_SIZE
1831 if $self->{read_size} > ($self->{max_read_size} || MAX_READ_SIZE);
1598 } 1832 }
1599 1833
1600 } elsif (defined $len) { 1834 } elsif (defined $len) {
1601 delete $self->{_rw}; 1835 delete $self->{_rw};
1602 $self->{_eof} = 1; 1836 $self->{_eof} = 1;
… …
1680 && ($tmp != $ERROR_SYSCALL || $!); 1914 && ($tmp != $ERROR_SYSCALL || $!);
1681 1915
1682 while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) { 1916 while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) {
1683 $self->{wbuf} .= $tmp; 1917 $self->{wbuf} .= $tmp;
1684 $self->_drain_wbuf; 1918 $self->_drain_wbuf;
1919 $self->{tls} or return; # tls session might have gone away in callback
1685 } 1920 }
1686 1921
1687 $self->{_on_starttls} 1922 $self->{_on_starttls}
1688 and Net::SSLeay::state ($self->{tls}) == Net::SSLeay::ST_OK () 1923 and Net::SSLeay::state ($self->{tls}) == Net::SSLeay::ST_OK ()
1689 and (delete $self->{_on_starttls})->($self, 1, "TLS/SSL connection established"); 1924 and (delete $self->{_on_starttls})->($self, 1, "TLS/SSL connection established");
… …
1711context in C<< $handle->{tls_ctx} >> after this call and can be used or 1946context in C<< $handle->{tls_ctx} >> after this call and can be used or
1712changed to your liking. Note that the handshake might have already started 1947changed to your liking. Note that the handshake might have already started
1713when this function returns. 1948when this function returns.
1714 1949
1715Due to bugs in OpenSSL, it might or might not be possible to do multiple 1950Due to bugs in OpenSSL, it might or might not be possible to do multiple
1716handshakes on the same stream. Best do not attempt to use the stream after 1951handshakes on the same stream. It is best to not attempt to use the
1717stopping TLS. 1952stream after stopping TLS.
1953
1954This method may invoke callbacks (and therefore the handle might be
1955destroyed after it returns).
1718 1956
1719=cut 1957=cut
1720 1958
1721our %TLS_CACHE; #TODO not yet documented, should we? 1959our %TLS_CACHE; #TODO not yet documented, should we?
1722 1960
… …
1734 require Net::SSLeay; 1972 require Net::SSLeay;
1735 1973
1736 $ERROR_SYSCALL = Net::SSLeay::ERROR_SYSCALL (); 1974 $ERROR_SYSCALL = Net::SSLeay::ERROR_SYSCALL ();
1737 $ERROR_WANT_READ = Net::SSLeay::ERROR_WANT_READ (); 1975 $ERROR_WANT_READ = Net::SSLeay::ERROR_WANT_READ ();
1738 1976
1739 $tls = $self->{tls}; 1977 $tls = delete $self->{tls};
1740 $ctx = $self->{tls_ctx}; 1978 $ctx = $self->{tls_ctx};
1741 1979
1742 local $Carp::CarpLevel = 1; # skip ourselves when creating a new context or session 1980 local $Carp::CarpLevel = 1; # skip ourselves when creating a new context or session
1743 1981
1744 if ("HASH" eq ref $ctx) { 1982 if ("HASH" eq ref $ctx) {
… …
1773 Net::SSLeay::CTX_set_mode ($tls, 1|2); 2011 Net::SSLeay::CTX_set_mode ($tls, 1|2);
1774 2012
1775 $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); 2013 $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1776 $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); 2014 $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1777 2015
1778 Net::SSLeay::BIO_write ($self->{_rbio}, delete $self->{rbuf}); 2016 Net::SSLeay::BIO_write ($self->{_rbio}, $self->{rbuf});
2017 $self->{rbuf} = "";
1779 2018
1780 Net::SSLeay::set_bio ($tls, $self->{_rbio}, $self->{_wbio}); 2019 Net::SSLeay::set_bio ($tls, $self->{_rbio}, $self->{_wbio});
1781 2020
1782 $self->{_on_starttls} = sub { $_[0]{on_starttls}(@_) } 2021 $self->{_on_starttls} = sub { $_[0]{on_starttls}(@_) }
1783 if $self->{on_starttls}; 2022 if $self->{on_starttls};
… …
1788 2027
1789=item $handle->stoptls 2028=item $handle->stoptls
1790 2029
1791Shuts down the SSL connection - this makes a proper EOF handshake by 2030Shuts down the SSL connection - this makes a proper EOF handshake by
1792sending a close notify to the other side, but since OpenSSL doesn't 2031sending a close notify to the other side, but since OpenSSL doesn't
1793support non-blocking shut downs, it is not guarenteed that you can re-use 2032support non-blocking shut downs, it is not guaranteed that you can re-use
1794the stream afterwards. 2033the stream afterwards.
2034
2035This method may invoke callbacks (and therefore the handle might be
2036destroyed after it returns).
1795 2037
1796=cut 2038=cut
1797 2039
1798sub stoptls { 2040sub stoptls {
1799 my ($self) = @_; 2041 my ($self) = @_;
1800 2042
1801 if ($self->{tls}) { 2043 if ($self->{tls} && $self->{fh}) {
1802 Net::SSLeay::shutdown ($self->{tls}); 2044 Net::SSLeay::shutdown ($self->{tls});
1803 2045
1804 &_dotls; 2046 &_dotls;
1805 2047
1806# # we don't give a shit. no, we do, but we can't. no...#d# 2048# # we don't give a shit. no, we do, but we can't. no...#d#
… …
1818 if $self->{tls} > 0; 2060 if $self->{tls} > 0;
1819 2061
1820 delete @$self{qw(_rbio _wbio _tls_wbuf _on_starttls)}; 2062 delete @$self{qw(_rbio _wbio _tls_wbuf _on_starttls)};
1821} 2063}
1822 2064
2065=item $handle->resettls
2066
2067This rarely-used method simply resets and TLS state on the handle, usually
2068causing data loss.
2069
2070One case where it may be useful is when you want to skip over the data in
2071the stream but you are not interested in interpreting it, so data loss is
2072no concern.
2073
2074=cut
2075
2076*resettls = \&_freetls;
2077
1823sub DESTROY { 2078sub DESTROY {
1824 my ($self) = @_; 2079 my ($self) = @_;
1825 2080
1826 &_freetls; 2081 &_freetls;
1827 2082
… …
1836 push @linger, AE::io $fh, 1, sub { 2091 push @linger, AE::io $fh, 1, sub {
1837 my $len = syswrite $fh, $wbuf, length $wbuf; 2092 my $len = syswrite $fh, $wbuf, length $wbuf;
1838 2093
1839 if ($len > 0) { 2094 if ($len > 0) {
1840 substr $wbuf, 0, $len, ""; 2095 substr $wbuf, 0, $len, "";
1841 } else { 2096 } elsif (defined $len || ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK)) {
1842 @linger = (); # end 2097 @linger = (); # end
1843 } 2098 }
1844 }; 2099 };
1845 push @linger, AE::timer $linger, 0, sub { 2100 push @linger, AE::timer $linger, 0, sub {
1846 @linger = (); 2101 @linger = ();
… …
1883 2138
1884sub AnyEvent::Handle::destroyed::AUTOLOAD { 2139sub AnyEvent::Handle::destroyed::AUTOLOAD {
1885 #nop 2140 #nop
1886} 2141}
1887 2142
2143=item $handle->destroyed
2144
2145Returns false as long as the handle hasn't been destroyed by a call to C<<
2146->destroy >>, true otherwise.
2147
2148Can be useful to decide whether the handle is still valid after some
2149callback possibly destroyed the handle. For example, C<< ->push_write >>,
2150C<< ->starttls >> and other methods can call user callbacks, which in turn
2151can destroy the handle, so work can be avoided by checking sometimes:
2152
2153 $hdl->starttls ("accept");
2154 return if $hdl->destroyed;
2155 $hdl->push_write (...
2156
2157Note that the call to C<push_write> will silently be ignored if the handle
2158has been destroyed, so often you can just ignore the possibility of the
2159handle being destroyed.
2160
2161=cut
2162
2163sub destroyed { 0 }
2164sub AnyEvent::Handle::destroyed::destroyed { 1 }
2165
1888=item AnyEvent::Handle::TLS_CTX 2166=item AnyEvent::Handle::TLS_CTX
1889 2167
1890This function creates and returns the AnyEvent::TLS object used by default 2168This function creates and returns the AnyEvent::TLS object used by default
1891for TLS mode. 2169for TLS mode.
1892 2170
… …
1919 2197
1920It is only safe to "forget" the reference inside EOF or error callbacks, 2198It is only safe to "forget" the reference inside EOF or error callbacks,
1921from within all other callbacks, you need to explicitly call the C<< 2199from within all other callbacks, you need to explicitly call the C<<
1922->destroy >> method. 2200->destroy >> method.
1923 2201
2202=item Why is my C<on_eof> callback never called?
2203
2204Probably because your C<on_error> callback is being called instead: When
2205you have outstanding requests in your read queue, then an EOF is
2206considered an error as you clearly expected some data.
2207
2208To avoid this, make sure you have an empty read queue whenever your handle
2209is supposed to be "idle" (i.e. connection closes are O.K.). You can set
2210an C<on_read> handler that simply pushes the first read requests in the
2211queue.
2212
2213See also the next question, which explains this in a bit more detail.
2214
2215=item How can I serve requests in a loop?
2216
2217Most protocols consist of some setup phase (authentication for example)
2218followed by a request handling phase, where the server waits for requests
2219and handles them, in a loop.
2220
2221There are two important variants: The first (traditional, better) variant
2222handles requests until the server gets some QUIT command, causing it to
2223close the connection first (highly desirable for a busy TCP server). A
2224client dropping the connection is an error, which means this variant can
2225detect an unexpected detection close.
2226
2227To handle this case, always make sure you have a on-empty read queue, by
2228pushing the "read request start" handler on it:
2229
2230 # we assume a request starts with a single line
2231 my @start_request; @start_request = (line => sub {
2232 my ($hdl, $line) = @_;
2233
2234 ... handle request
2235
2236 # push next request read, possibly from a nested callback
2237 $hdl->push_read (@start_request);
2238 });
2239
2240 # auth done, now go into request handling loop
2241 # now push the first @start_request
2242 $hdl->push_read (@start_request);
2243
2244By always having an outstanding C<push_read>, the handle always expects
2245some data and raises the C<EPIPE> error when the connction is dropped
2246unexpectedly.
2247
2248The second variant is a protocol where the client can drop the connection
2249at any time. For TCP, this means that the server machine may run out of
2250sockets easier, and in general, it means you cannot distinguish a protocl
2251failure/client crash from a normal connection close. Nevertheless, these
2252kinds of protocols are common (and sometimes even the best solution to the
2253problem).
2254
2255Having an outstanding read request at all times is possible if you ignore
2256C<EPIPE> errors, but this doesn't help with when the client drops the
2257connection during a request, which would still be an error.
2258
2259A better solution is to push the initial request read in an C<on_read>
2260callback. This avoids an error, as when the server doesn't expect data
2261(i.e. is idly waiting for the next request, an EOF will not raise an
2262error, but simply result in an C<on_eof> callback. It is also a bit slower
2263and simpler:
2264
2265 # auth done, now go into request handling loop
2266 $hdl->on_read (sub {
2267 my ($hdl) = @_;
2268
2269 # called each time we receive data but the read queue is empty
2270 # simply start read the request
2271
2272 $hdl->push_read (line => sub {
2273 my ($hdl, $line) = @_;
2274
2275 ... handle request
2276
2277 # do nothing special when the request has been handled, just
2278 # let the request queue go empty.
2279 });
2280 });
2281
1924=item I get different callback invocations in TLS mode/Why can't I pause 2282=item I get different callback invocations in TLS mode/Why can't I pause
1925reading? 2283reading?
1926 2284
1927Unlike, say, TCP, TLS connections do not consist of two independent 2285Unlike, say, TCP, TLS connections do not consist of two independent
1928communication channels, one for each direction. Or put differently. The 2286communication channels, one for each direction. Or put differently, the
1929read and write directions are not independent of each other: you cannot 2287read and write directions are not independent of each other: you cannot
1930write data unless you are also prepared to read, and vice versa. 2288write data unless you are also prepared to read, and vice versa.
1931 2289
1932This can mean than, in TLS mode, you might get C<on_error> or C<on_eof> 2290This means that, in TLS mode, you might get C<on_error> or C<on_eof>
1933callback invocations when you are not expecting any read data - the reason 2291callback invocations when you are not expecting any read data - the reason
1934is that AnyEvent::Handle always reads in TLS mode. 2292is that AnyEvent::Handle always reads in TLS mode.
1935 2293
1936During the connection, you have to make sure that you always have a 2294During the connection, you have to make sure that you always have a
1937non-empty read-queue, or an C<on_read> watcher. At the end of the 2295non-empty read-queue, or an C<on_read> watcher. At the end of the
… …
1949 $handle->on_eof (undef); 2307 $handle->on_eof (undef);
1950 $handle->on_error (sub { 2308 $handle->on_error (sub {
1951 my $data = delete $_[0]{rbuf}; 2309 my $data = delete $_[0]{rbuf};
1952 }); 2310 });
1953 2311
2312Note that this example removes the C<rbuf> member from the handle object,
2313which is not normally allowed by the API. It is expressly permitted in
2314this case only, as the handle object needs to be destroyed afterwards.
2315
1954The reason to use C<on_error> is that TCP connections, due to latencies 2316The reason to use C<on_error> is that TCP connections, due to latencies
1955and packets loss, might get closed quite violently with an error, when in 2317and packets loss, might get closed quite violently with an error, when in
1956fact, all data has been received. 2318fact all data has been received.
1957 2319
1958It is usually better to use acknowledgements when transferring data, 2320It is usually better to use acknowledgements when transferring data,
1959to make sure the other side hasn't just died and you got the data 2321to make sure the other side hasn't just died and you got the data
1960intact. This is also one reason why so many internet protocols have an 2322intact. This is also one reason why so many internet protocols have an
1961explicit QUIT command. 2323explicit QUIT command.
… …
1968C<low_water_mark> this will be called precisely when all data has been 2330C<low_water_mark> this will be called precisely when all data has been
1969written to the socket: 2331written to the socket:
1970 2332
1971 $handle->push_write (...); 2333 $handle->push_write (...);
1972 $handle->on_drain (sub { 2334 $handle->on_drain (sub {
1973 warn "all data submitted to the kernel\n"; 2335 AE::log debug => "all data submitted to the kernel\n";
1974 undef $handle; 2336 undef $handle;
1975 }); 2337 });
1976 2338
1977If you just want to queue some data and then signal EOF to the other side, 2339If you just want to queue some data and then signal EOF to the other side,
1978consider using C<< ->push_shutdown >> instead. 2340consider using C<< ->push_shutdown >> instead.
1979 2341
1980=item I want to contact a TLS/SSL server, I don't care about security. 2342=item I want to contact a TLS/SSL server, I don't care about security.
1981 2343
1982If your TLS server is a pure TLS server (e.g. HTTPS) that only speaks TLS, 2344If your TLS server is a pure TLS server (e.g. HTTPS) that only speaks TLS,
1983simply connect to it and then create the AnyEvent::Handle with the C<tls> 2345connect to it and then create the AnyEvent::Handle with the C<tls>
1984parameter: 2346parameter:
1985 2347
1986 tcp_connect $host, $port, sub { 2348 tcp_connect $host, $port, sub {
1987 my ($fh) = @_; 2349 my ($fh) = @_;
1988 2350
… …
2088 2450
2089=item * all members not documented here and not prefixed with an underscore 2451=item * all members not documented here and not prefixed with an underscore
2090are free to use in subclasses. 2452are free to use in subclasses.
2091 2453
2092Of course, new versions of AnyEvent::Handle may introduce more "public" 2454Of course, new versions of AnyEvent::Handle may introduce more "public"
2093member variables, but thats just life, at least it is documented. 2455member variables, but that's just life. At least it is documented.
2094 2456
2095=back 2457=back
2096 2458
2097=head1 AUTHOR 2459=head1 AUTHOR
2098 2460

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