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Revision 1.159 by root, Fri Jul 24 12:35:58 2009 UTC vs.
Revision 1.237 by root, Tue Jul 30 23:14:32 2013 UTC

1package AnyEvent::Handle;
2
3use Scalar::Util ();
4use Carp ();
5use Errno qw(EAGAIN EINTR);
6
7use AnyEvent (); BEGIN { AnyEvent::common_sense }
8use AnyEvent::Util qw(WSAEWOULDBLOCK);
9
10=head1 NAME 1=head1 NAME
11 2
12AnyEvent::Handle - non-blocking I/O on file handles via AnyEvent 3AnyEvent::Handle - non-blocking I/O on streaming handles via AnyEvent
13
14=cut
15
16our $VERSION = 4.86;
17 4
18=head1 SYNOPSIS 5=head1 SYNOPSIS
19 6
20 use AnyEvent; 7 use AnyEvent;
21 use AnyEvent::Handle; 8 use AnyEvent::Handle;
24 11
25 my $hdl; $hdl = new AnyEvent::Handle 12 my $hdl; $hdl = new AnyEvent::Handle
26 fh => \*STDIN, 13 fh => \*STDIN,
27 on_error => sub { 14 on_error => sub {
28 my ($hdl, $fatal, $msg) = @_; 15 my ($hdl, $fatal, $msg) = @_;
29 warn "got error $msg\n"; 16 AE::log error => $msg;
30 $hdl->destroy; 17 $hdl->destroy;
31 $cv->send; 18 $cv->send;
32 ); 19 };
33 20
34 # send some request line 21 # send some request line
35 $hdl->push_write ("getinfo\015\012"); 22 $hdl->push_write ("getinfo\015\012");
36 23
37 # read the response line 24 # read the response line
38 $hdl->push_read (line => sub { 25 $hdl->push_read (line => sub {
39 my ($hdl, $line) = @_; 26 my ($hdl, $line) = @_;
40 warn "got line <$line>\n"; 27 say "got line <$line>";
41 $cv->send; 28 $cv->send;
42 }); 29 });
43 30
44 $cv->recv; 31 $cv->recv;
45 32
46=head1 DESCRIPTION 33=head1 DESCRIPTION
47 34
48This 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
49filehandles. 36stream-based filehandles (sockets, pipes, and other stream things).
50 37
51The L<AnyEvent::Intro> tutorial contains some well-documented 38The L<AnyEvent::Intro> tutorial contains some well-documented
52AnyEvent::Handle examples. 39AnyEvent::Handle examples.
53 40
54In the following, when the documentation refers to of "bytes" then this 41In the following, where the documentation refers to "bytes", it means
55means characters. As sysread and syswrite are used for all I/O, their 42characters. As sysread and syswrite are used for all I/O, their
56treatment of characters applies to this module as well. 43treatment of characters applies to this module as well.
57 44
58At 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
59C<on_error> callback. 46C<on_error> callback.
60 47
61All callbacks will be invoked with the handle object as their first 48All callbacks will be invoked with the handle object as their first
62argument. 49argument.
63 50
51=cut
52
53package AnyEvent::Handle;
54
55use Scalar::Util ();
56use List::Util ();
57use Carp ();
58use Errno qw(EAGAIN EINTR);
59
60use AnyEvent (); BEGIN { AnyEvent::common_sense }
61use AnyEvent::Util qw(WSAEWOULDBLOCK);
62
63our $VERSION = $AnyEvent::VERSION;
64
65sub _load_func($) {
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
64=head1 METHODS 82=head1 METHODS
65 83
66=over 4 84=over 4
67 85
68=item $handle = B<new> AnyEvent::TLS fh => $filehandle, key => value... 86=item $handle = B<new> AnyEvent::Handle fh => $filehandle, key => value...
69 87
70The constructor supports these arguments (all as C<< key => value >> pairs). 88The constructor supports these arguments (all as C<< key => value >> pairs).
71 89
72=over 4 90=over 4
73 91
84C<AnyEvent::Socket::tcp_connect>. The C<$host> additionally becomes the 102C<AnyEvent::Socket::tcp_connect>. The C<$host> additionally becomes the
85default C<peername>. 103default C<peername>.
86 104
87You have to specify either this parameter, or C<fh>, above. 105You have to specify either this parameter, or C<fh>, above.
88 106
107It is possible to push requests on the read and write queues, and modify
108properties of the stream, even while AnyEvent::Handle is connecting.
109
89When this parameter is specified, then the C<on_prepare>, 110When this parameter is specified, then the C<on_prepare>,
90C<on_connect_error> and C<on_connect> callbacks will be called under the 111C<on_connect_error> and C<on_connect> callbacks will be called under the
91appropriate circumstances: 112appropriate circumstances:
92 113
93=over 4 114=over 4
94 115
95=item on_prepare => $cb->($handle) 116=item on_prepare => $cb->($handle)
96 117
97This (rarely used) callback is called before a new connection is 118This (rarely used) callback is called before a new connection is
98attempted, 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
99prepare the file handle with parameters required for the actual connect 121file handle with parameters required for the actual connect (as opposed to
100(as opposed to settings that can be changed when the connection is already 122settings that can be changed when the connection is already established).
101established). 123
124The return value of this callback should be the connect timeout value in
125seconds (or C<0>, or C<undef>, or the empty list, to indicate that the
126default timeout is to be used).
102 127
103=item on_connect => $cb->($handle, $host, $port, $retry->()) 128=item on_connect => $cb->($handle, $host, $port, $retry->())
104 129
105This callback is called when a connection has been successfully established. 130This callback is called when a connection has been successfully established.
106 131
107The actual numeric host and port (the socket peername) are passed as 132The peer's numeric host and port (the socket peername) are passed as
108parameters, together with a retry callback. 133parameters, together with a retry callback. At the time it is called the
134read and write queues, EOF status, TLS status and similar properties of
135the handle will have been reset.
109 136
137It is not allowed to use the read or write queues while the handle object
138is connecting.
139
110When, for some reason, the handle is not acceptable, then calling 140If, for some reason, the handle is not acceptable, calling C<$retry> will
111C<$retry> will continue with the next conenction target (in case of 141continue with the next connection target (in case of multi-homed hosts or
112multi-homed hosts or SRV records there can be multiple connection 142SRV records there can be multiple connection endpoints). The C<$retry>
113endpoints). When it is called then the read and write queues, eof status, 143callback can be invoked after the connect callback returns, i.e. one can
114tls status and similar properties of the handle are being reset. 144start a handshake and then decide to retry with the next host if the
145handshake fails.
115 146
116In most cases, ignoring the C<$retry> parameter is the way to go. 147In most cases, you should ignore the C<$retry> parameter.
117 148
118=item on_connect_error => $cb->($handle, $message) 149=item on_connect_error => $cb->($handle, $message)
119 150
120This callback is called when the conenction could not be 151This callback is called when the connection could not be
121established. C<$!> will contain the relevant error code, and C<$message> a 152established. C<$!> will contain the relevant error code, and C<$message> a
122message describing it (usually the same as C<"$!">). 153message describing it (usually the same as C<"$!">).
123 154
124If this callback isn't specified, then C<on_error> will be called with a 155If this callback isn't specified, then C<on_error> will be called with a
125fatal error instead. 156fatal error instead.
128 159
129=item on_error => $cb->($handle, $fatal, $message) 160=item on_error => $cb->($handle, $fatal, $message)
130 161
131This is the error callback, which is called when, well, some error 162This is the error callback, which is called when, well, some error
132occured, such as not being able to resolve the hostname, failure to 163occured, such as not being able to resolve the hostname, failure to
133connect or a read error. 164connect, or a read error.
134 165
135Some errors are fatal (which is indicated by C<$fatal> being true). On 166Some errors are fatal (which is indicated by C<$fatal> being true). On
136fatal errors the handle object will be destroyed (by a call to C<< -> 167fatal errors the handle object will be destroyed (by a call to C<< ->
137destroy >>) after invoking the error callback (which means you are free to 168destroy >>) after invoking the error callback (which means you are free to
138examine the handle object). Examples of fatal errors are an EOF condition 169examine the handle object). Examples of fatal errors are an EOF condition
139with active (but unsatisifable) read watchers (C<EPIPE>) or I/O errors. In 170with active (but unsatisfiable) read watchers (C<EPIPE>) or I/O errors. In
140cases where the other side can close the connection at their will it is 171cases where the other side can close the connection at will, it is
141often easiest to not report C<EPIPE> errors in this callback. 172often easiest to not report C<EPIPE> errors in this callback.
142 173
143AnyEvent::Handle tries to find an appropriate error code for you to check 174AnyEvent::Handle tries to find an appropriate error code for you to check
144against, but in some cases (TLS errors), this does not work well. It is 175against, but in some cases (TLS errors), this does not work well.
145recommended to always output the C<$message> argument in human-readable
146error messages (it's usually the same as C<"$!">).
147 176
177If you report the error to the user, it is recommended to always output
178the C<$message> argument in human-readable error messages (you don't need
179to report C<"$!"> if you report C<$message>).
180
181If you want to react programmatically to the error, then looking at C<$!>
182and comparing it against some of the documented C<Errno> values is usually
183better than looking at the C<$message>.
184
148Non-fatal errors can be retried by simply returning, but it is recommended 185Non-fatal errors can be retried by returning, but it is recommended
149to simply ignore this parameter and instead abondon the handle object 186to simply ignore this parameter and instead abondon the handle object
150when this callback is invoked. Examples of non-fatal errors are timeouts 187when this callback is invoked. Examples of non-fatal errors are timeouts
151C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>). 188C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>).
152 189
153On callback entrance, the value of C<$!> contains the operating system 190On entry to the callback, the value of C<$!> contains the operating
154error code (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT>, C<EBADMSG> or 191system error code (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT>, C<EBADMSG> or
155C<EPROTO>). 192C<EPROTO>).
156 193
157While not mandatory, it is I<highly> recommended to set this callback, as 194While not mandatory, it is I<highly> recommended to set this callback, as
158you will not be notified of errors otherwise. The default simply calls 195you will not be notified of errors otherwise. The default just calls
159C<croak>. 196C<croak>.
160 197
161=item on_read => $cb->($handle) 198=item on_read => $cb->($handle)
162 199
163This sets the default read callback, which is called when data arrives 200This sets the default read callback, which is called when data arrives
168To access (and remove data from) the read buffer, use the C<< ->rbuf >> 205To access (and remove data from) the read buffer, use the C<< ->rbuf >>
169method or access the C<< $handle->{rbuf} >> member directly. Note that you 206method or access the C<< $handle->{rbuf} >> member directly. Note that you
170must not enlarge or modify the read buffer, you can only remove data at 207must not enlarge or modify the read buffer, you can only remove data at
171the beginning from it. 208the beginning from it.
172 209
210You can also call C<< ->push_read (...) >> or any other function that
211modifies the read queue. Or do both. Or ...
212
173When an EOF condition is detected then AnyEvent::Handle will first try to 213When an EOF condition is detected, AnyEvent::Handle will first try to
174feed all the remaining data to the queued callbacks and C<on_read> before 214feed all the remaining data to the queued callbacks and C<on_read> before
175calling the C<on_eof> callback. If no progress can be made, then a fatal 215calling the C<on_eof> callback. If no progress can be made, then a fatal
176error will be raised (with C<$!> set to C<EPIPE>). 216error will be raised (with C<$!> set to C<EPIPE>).
177 217
178Note that, unlike requests in the read queue, an C<on_read> callback 218Note that, unlike requests in the read queue, an C<on_read> callback
196If an EOF condition has been detected but no C<on_eof> callback has been 236If an EOF condition has been detected but no C<on_eof> callback has been
197set, then a fatal error will be raised with C<$!> set to <0>. 237set, then a fatal error will be raised with C<$!> set to <0>.
198 238
199=item on_drain => $cb->($handle) 239=item on_drain => $cb->($handle)
200 240
201This sets the callback that is called when the write buffer becomes empty 241This sets the callback that is called once when the write buffer becomes
202(or when the callback is set and the buffer is empty already). 242empty (and immediately when the handle object is created).
203 243
204To append to the write buffer, use the C<< ->push_write >> method. 244To append to the write buffer, use the C<< ->push_write >> method.
205 245
206This callback is useful when you don't want to put all of your write data 246This callback is useful when you don't want to put all of your write data
207into the queue at once, for example, when you want to write the contents 247into the queue at once, for example, when you want to write the contents
209memory and push it into the queue, but instead only read more data from 249memory and push it into the queue, but instead only read more data from
210the file when the write queue becomes empty. 250the file when the write queue becomes empty.
211 251
212=item timeout => $fractional_seconds 252=item timeout => $fractional_seconds
213 253
254=item rtimeout => $fractional_seconds
255
256=item wtimeout => $fractional_seconds
257
214If non-zero, then this enables an "inactivity" timeout: whenever this many 258If non-zero, then these enables an "inactivity" timeout: whenever this
215seconds pass without a successful read or write on the underlying file 259many seconds pass without a successful read or write on the underlying
216handle, the C<on_timeout> callback will be invoked (and if that one is 260file handle (or a call to C<timeout_reset>), the C<on_timeout> callback
217missing, a non-fatal C<ETIMEDOUT> error will be raised). 261will be invoked (and if that one is missing, a non-fatal C<ETIMEDOUT>
262error will be raised).
218 263
264There are three variants of the timeouts that work independently of each
265other, for both read and write (triggered when nothing was read I<OR>
266written), just read (triggered when nothing was read), and just write:
267C<timeout>, C<rtimeout> and C<wtimeout>, with corresponding callbacks
268C<on_timeout>, C<on_rtimeout> and C<on_wtimeout>, and reset functions
269C<timeout_reset>, C<rtimeout_reset>, and C<wtimeout_reset>.
270
219Note that timeout processing is also active when you currently do not have 271Note that timeout processing is active even when you do not have any
220any outstanding read or write requests: If you plan to keep the connection 272outstanding read or write requests: If you plan to keep the connection
221idle then you should disable the timout temporarily or ignore the timeout 273idle then you should disable the timeout temporarily or ignore the
222in the C<on_timeout> callback, in which case AnyEvent::Handle will simply 274timeout in the corresponding C<on_timeout> callback, in which case
223restart the timeout. 275AnyEvent::Handle will simply restart the timeout.
224 276
225Zero (the default) disables this timeout. 277Zero (the default) disables the corresponding timeout.
226 278
227=item on_timeout => $cb->($handle) 279=item on_timeout => $cb->($handle)
280
281=item on_rtimeout => $cb->($handle)
282
283=item on_wtimeout => $cb->($handle)
228 284
229Called whenever the inactivity timeout passes. If you return from this 285Called whenever the inactivity timeout passes. If you return from this
230callback, then the timeout will be reset as if some activity had happened, 286callback, then the timeout will be reset as if some activity had happened,
231so this condition is not fatal in any way. 287so this condition is not fatal in any way.
232 288
240be configured to accept only so-and-so much data that it cannot act on 296be configured to accept only so-and-so much data that it cannot act on
241(for example, when expecting a line, an attacker could send an unlimited 297(for example, when expecting a line, an attacker could send an unlimited
242amount of data without a callback ever being called as long as the line 298amount of data without a callback ever being called as long as the line
243isn't finished). 299isn't finished).
244 300
301=item wbuf_max => <bytes>
302
303If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)
304when the write buffer ever (strictly) exceeds this size. This is useful to
305avoid some forms of denial-of-service attacks.
306
307Although the units of this parameter is bytes, this is the I<raw> number
308of bytes not yet accepted by the kernel. This can make a difference when
309you e.g. use TLS, as TLS typically makes your write data larger (but it
310can also make it smaller due to compression).
311
312As an example of when this limit is useful, take a chat server that sends
313chat messages to a client. If the client does not read those in a timely
314manner then the send buffer in the server would grow unbounded.
315
245=item autocork => <boolean> 316=item autocork => <boolean>
246 317
247When disabled (the default), then C<push_write> will try to immediately 318When disabled (the default), C<push_write> will try to immediately
248write the data to the handle, if possible. This avoids having to register 319write the data to the handle if possible. This avoids having to register
249a write watcher and wait for the next event loop iteration, but can 320a write watcher and wait for the next event loop iteration, but can
250be inefficient if you write multiple small chunks (on the wire, this 321be inefficient if you write multiple small chunks (on the wire, this
251disadvantage is usually avoided by your kernel's nagle algorithm, see 322disadvantage is usually avoided by your kernel's nagle algorithm, see
252C<no_delay>, but this option can save costly syscalls). 323C<no_delay>, but this option can save costly syscalls).
253 324
254When enabled, then writes will always be queued till the next event loop 325When enabled, writes will always be queued till the next event loop
255iteration. This is efficient when you do many small writes per iteration, 326iteration. This is efficient when you do many small writes per iteration,
256but less efficient when you do a single write only per iteration (or when 327but less efficient when you do a single write only per iteration (or when
257the write buffer often is full). It also increases write latency. 328the write buffer often is full). It also increases write latency.
258 329
259=item no_delay => <boolean> 330=item no_delay => <boolean>
263the Nagle algorithm, and usually it is beneficial. 334the Nagle algorithm, and usually it is beneficial.
264 335
265In some situations you want as low a delay as possible, which can be 336In some situations you want as low a delay as possible, which can be
266accomplishd by setting this option to a true value. 337accomplishd by setting this option to a true value.
267 338
268The default is your opertaing system's default behaviour (most likely 339The default is your operating system's default behaviour (most likely
269enabled), this option explicitly enables or disables it, if possible. 340enabled). This option explicitly enables or disables it, if possible.
341
342=item keepalive => <boolean>
343
344Enables (default disable) the SO_KEEPALIVE option on the stream socket:
345normally, TCP connections have no time-out once established, so TCP
346connections, once established, can stay alive forever even when the other
347side has long gone. TCP keepalives are a cheap way to take down long-lived
348TCP connections when the other side becomes unreachable. While the default
349is OS-dependent, TCP keepalives usually kick in after around two hours,
350and, if the other side doesn't reply, take down the TCP connection some 10
351to 15 minutes later.
352
353It is harmless to specify this option for file handles that do not support
354keepalives, and enabling it on connections that are potentially long-lived
355is usually a good idea.
356
357=item oobinline => <boolean>
358
359BSD majorly fucked up the implementation of TCP urgent data. The result
360is that almost no OS implements TCP according to the specs, and every OS
361implements it slightly differently.
362
363If you want to handle TCP urgent data, then setting this flag (the default
364is enabled) gives you the most portable way of getting urgent data, by
365putting it into the stream.
366
367Since BSD emulation of OOB data on top of TCP's urgent data can have
368security implications, AnyEvent::Handle sets this flag automatically
369unless explicitly specified. Note that setting this flag after
370establishing a connection I<may> be a bit too late (data loss could
371already have occured on BSD systems), but at least it will protect you
372from most attacks.
270 373
271=item read_size => <bytes> 374=item read_size => <bytes>
272 375
273The default read block size (the amount of bytes this module will 376The initial read block size, the number of bytes this module will try
274try to read during each loop iteration, which affects memory 377to read during each loop iteration. Each handle object will consume
275requirements). Default: C<8192>. 378at least this amount of memory for the read buffer as well, so when
379handling many connections watch out for memory requirements). See also
380C<max_read_size>. Default: C<2048>.
381
382=item max_read_size => <bytes>
383
384The maximum read buffer size used by the dynamic adjustment
385algorithm: Each time AnyEvent::Handle can read C<read_size> bytes in
386one go it will double C<read_size> up to the maximum given by this
387option. Default: C<131072> or C<read_size>, whichever is higher.
276 388
277=item low_water_mark => <bytes> 389=item low_water_mark => <bytes>
278 390
279Sets the amount of bytes (default: C<0>) that make up an "empty" write 391Sets the number of bytes (default: C<0>) that make up an "empty" write
280buffer: If the write reaches this size or gets even samller it is 392buffer: If the buffer reaches this size or gets even samller it is
281considered empty. 393considered empty.
282 394
283Sometimes it can be beneficial (for performance reasons) to add data to 395Sometimes it can be beneficial (for performance reasons) to add data to
284the write buffer before it is fully drained, but this is a rare case, as 396the write buffer before it is fully drained, but this is a rare case, as
285the operating system kernel usually buffers data as well, so the default 397the operating system kernel usually buffers data as well, so the default
286is good in almost all cases. 398is good in almost all cases.
287 399
288=item linger => <seconds> 400=item linger => <seconds>
289 401
290If non-zero (default: C<3600>), then the destructor of the 402If this is non-zero (default: C<3600>), the destructor of the
291AnyEvent::Handle object will check whether there is still outstanding 403AnyEvent::Handle object will check whether there is still outstanding
292write data and will install a watcher that will write this data to the 404write data and will install a watcher that will write this data to the
293socket. No errors will be reported (this mostly matches how the operating 405socket. No errors will be reported (this mostly matches how the operating
294system treats outstanding data at socket close time). 406system treats outstanding data at socket close time).
295 407
302A string used to identify the remote site - usually the DNS hostname 414A string used to identify the remote site - usually the DNS hostname
303(I<not> IDN!) used to create the connection, rarely the IP address. 415(I<not> IDN!) used to create the connection, rarely the IP address.
304 416
305Apart from being useful in error messages, this string is also used in TLS 417Apart from being useful in error messages, this string is also used in TLS
306peername verification (see C<verify_peername> in L<AnyEvent::TLS>). This 418peername verification (see C<verify_peername> in L<AnyEvent::TLS>). This
307verification will be skipped when C<peername> is not specified or 419verification will be skipped when C<peername> is not specified or is
308C<undef>. 420C<undef>.
309 421
310=item tls => "accept" | "connect" | Net::SSLeay::SSL object 422=item tls => "accept" | "connect" | Net::SSLeay::SSL object
311 423
312When this parameter is given, it enables TLS (SSL) mode, that means 424When this parameter is given, it enables TLS (SSL) mode, that means
313AnyEvent will start a TLS handshake as soon as the conenction has been 425AnyEvent will start a TLS handshake as soon as the connection has been
314established and will transparently encrypt/decrypt data afterwards. 426established and will transparently encrypt/decrypt data afterwards.
315 427
316All TLS protocol errors will be signalled as C<EPROTO>, with an 428All TLS protocol errors will be signalled as C<EPROTO>, with an
317appropriate error message. 429appropriate error message.
318 430
319TLS mode requires Net::SSLeay to be installed (it will be loaded 431TLS mode requires Net::SSLeay to be installed (it will be loaded
320automatically when you try to create a TLS handle): this module doesn't 432automatically when you try to create a TLS handle): this module doesn't
321have a dependency on that module, so if your module requires it, you have 433have a dependency on that module, so if your module requires it, you have
322to add the dependency yourself. 434to add the dependency yourself. If Net::SSLeay cannot be loaded or is too
435old, you get an C<EPROTO> error.
323 436
324Unlike TCP, TLS has a server and client side: for the TLS server side, use 437Unlike TCP, TLS has a server and client side: for the TLS server side, use
325C<accept>, and for the TLS client side of a connection, use C<connect> 438C<accept>, and for the TLS client side of a connection, use C<connect>
326mode. 439mode.
327 440
338B<IMPORTANT:> since Net::SSLeay "objects" are really only integers, 451B<IMPORTANT:> since Net::SSLeay "objects" are really only integers,
339passing in the wrong integer will lead to certain crash. This most often 452passing in the wrong integer will lead to certain crash. This most often
340happens when one uses a stylish C<< tls => 1 >> and is surprised about the 453happens when one uses a stylish C<< tls => 1 >> and is surprised about the
341segmentation fault. 454segmentation fault.
342 455
343See the C<< ->starttls >> method for when need to start TLS negotiation later. 456Use the C<< ->starttls >> method if you need to start TLS negotiation later.
344 457
345=item tls_ctx => $anyevent_tls 458=item tls_ctx => $anyevent_tls
346 459
347Use the given C<AnyEvent::TLS> object to create the new TLS connection 460Use the given C<AnyEvent::TLS> object to create the new TLS connection
348(unless a connection object was specified directly). If this parameter is 461(unless a connection object was specified directly). If this
349missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>. 462parameter is missing (or C<undef>), then AnyEvent::Handle will use
463C<AnyEvent::Handle::TLS_CTX>.
350 464
351Instead of an object, you can also specify a hash reference with C<< key 465Instead of an object, you can also specify a hash reference with C<< key
352=> value >> pairs. Those will be passed to L<AnyEvent::TLS> to create a 466=> value >> pairs. Those will be passed to L<AnyEvent::TLS> to create a
353new TLS context object. 467new TLS context object.
354 468
363 477
364TLS handshake failures will not cause C<on_error> to be invoked when this 478TLS handshake failures will not cause C<on_error> to be invoked when this
365callback is in effect, instead, the error message will be passed to C<on_starttls>. 479callback is in effect, instead, the error message will be passed to C<on_starttls>.
366 480
367Without this callback, handshake failures lead to C<on_error> being 481Without this callback, handshake failures lead to C<on_error> being
368called, as normal. 482called as usual.
369 483
370Note that you cannot call C<starttls> right again in this callback. If you 484Note that you cannot just call C<starttls> again in this callback. If you
371need to do that, start an zero-second timer instead whose callback can 485need to do that, start an zero-second timer instead whose callback can
372then call C<< ->starttls >> again. 486then call C<< ->starttls >> again.
373 487
374=item on_stoptls => $cb->($handle) 488=item on_stoptls => $cb->($handle)
375 489
423 $self->{connect}[0], 537 $self->{connect}[0],
424 $self->{connect}[1], 538 $self->{connect}[1],
425 sub { 539 sub {
426 my ($fh, $host, $port, $retry) = @_; 540 my ($fh, $host, $port, $retry) = @_;
427 541
542 delete $self->{_connect}; # no longer needed
543
428 if ($fh) { 544 if ($fh) {
429 $self->{fh} = $fh; 545 $self->{fh} = $fh;
430 546
431 delete $self->{_skip_drain_rbuf}; 547 delete $self->{_skip_drain_rbuf};
432 $self->_start; 548 $self->_start;
433 549
434 $self->{on_connect} 550 $self->{on_connect}
435 and $self->{on_connect}($self, $host, $port, sub { 551 and $self->{on_connect}($self, $host, $port, sub {
436 delete @$self{qw(fh _tw _ww _rw _eof _queue rbuf _wbuf tls _tls_rbuf _tls_wbuf)}; 552 delete @$self{qw(fh _tw _rtw _wtw _ww _rw _eof _queue rbuf _wbuf tls _tls_rbuf _tls_wbuf)};
437 $self->{_skip_drain_rbuf} = 1; 553 $self->{_skip_drain_rbuf} = 1;
438 &$retry; 554 &$retry;
439 }); 555 });
440 556
441 } else { 557 } else {
442 if ($self->{on_connect_error}) { 558 if ($self->{on_connect_error}) {
443 $self->{on_connect_error}($self, "$!"); 559 $self->{on_connect_error}($self, "$!");
444 $self->destroy; 560 $self->destroy if $self;
445 } else { 561 } else {
446 $self->fatal ($!, 1); 562 $self->_error ($!, 1);
447 } 563 }
448 } 564 }
449 }, 565 },
450 sub { 566 sub {
451 local $self->{fh} = $_[0]; 567 local $self->{fh} = $_[0];
452 568
569 $self->{on_prepare}
453 $self->{on_prepare}->($self) 570 ? $self->{on_prepare}->($self)
454 if $self->{on_prepare}; 571 : ()
455 } 572 }
456 ); 573 );
457 } 574 }
458 575
459 } else { 576 } else {
464} 581}
465 582
466sub _start { 583sub _start {
467 my ($self) = @_; 584 my ($self) = @_;
468 585
586 # too many clueless people try to use udp and similar sockets
587 # with AnyEvent::Handle, do them a favour.
588 my $type = getsockopt $self->{fh}, Socket::SOL_SOCKET (), Socket::SO_TYPE ();
589 Carp::croak "AnyEvent::Handle: only stream sockets supported, anything else will NOT work!"
590 if Socket::SOCK_STREAM () != (unpack "I", $type) && defined $type;
591
469 AnyEvent::Util::fh_nonblocking $self->{fh}, 1; 592 AnyEvent::Util::fh_nonblocking $self->{fh}, 1;
470 593
594 $self->{_activity} =
595 $self->{_ractivity} =
471 $self->{_activity} = AnyEvent->now; 596 $self->{_wactivity} = AE::now;
472 $self->_timeout;
473 597
598 $self->{read_size} ||= 2048;
599 $self->{max_read_size} = $self->{read_size}
600 if $self->{read_size} > ($self->{max_read_size} || MAX_READ_SIZE);
601
602 $self->timeout (delete $self->{timeout} ) if $self->{timeout};
603 $self->rtimeout (delete $self->{rtimeout} ) if $self->{rtimeout};
604 $self->wtimeout (delete $self->{wtimeout} ) if $self->{wtimeout};
605
474 $self->no_delay (delete $self->{no_delay}) if exists $self->{no_delay}; 606 $self->no_delay (delete $self->{no_delay} ) if exists $self->{no_delay} && $self->{no_delay};
607 $self->keepalive (delete $self->{keepalive}) if exists $self->{keepalive} && $self->{keepalive};
475 608
609 $self->oobinline (exists $self->{oobinline} ? delete $self->{oobinline} : 1);
610
476 $self->starttls (delete $self->{tls}, delete $self->{tls_ctx}) 611 $self->starttls (delete $self->{tls}, delete $self->{tls_ctx})
477 if $self->{tls}; 612 if $self->{tls};
478 613
479 $self->on_drain (delete $self->{on_drain}) if $self->{on_drain}; 614 $self->on_drain (delete $self->{on_drain} ) if $self->{on_drain};
480 615
481 $self->start_read 616 $self->start_read
482 if $self->{on_read} || @{ $self->{_queue} }; 617 if $self->{on_read} || @{ $self->{_queue} };
483}
484 618
485#sub _shutdown { 619 $self->_drain_wbuf;
486# my ($self) = @_; 620}
487#
488# delete @$self{qw(_tw _rw _ww fh wbuf on_read _queue)};
489# $self->{_eof} = 1; # tell starttls et. al to stop trying
490#
491# &_freetls;
492#}
493 621
494sub _error { 622sub _error {
495 my ($self, $errno, $fatal, $message) = @_; 623 my ($self, $errno, $fatal, $message) = @_;
496 624
497 $! = $errno; 625 $! = $errno;
498 $message ||= "$!"; 626 $message ||= "$!";
499 627
500 if ($self->{on_error}) { 628 if ($self->{on_error}) {
501 $self->{on_error}($self, $fatal, $message); 629 $self->{on_error}($self, $fatal, $message);
502 $self->destroy if $fatal; 630 $self->destroy if $fatal;
503 } elsif ($self->{fh}) { 631 } elsif ($self->{fh} || $self->{connect}) {
504 $self->destroy; 632 $self->destroy;
505 Carp::croak "AnyEvent::Handle uncaught error: $message"; 633 Carp::croak "AnyEvent::Handle uncaught error: $message";
506 } 634 }
507} 635}
508 636
534 $_[0]{on_eof} = $_[1]; 662 $_[0]{on_eof} = $_[1];
535} 663}
536 664
537=item $handle->on_timeout ($cb) 665=item $handle->on_timeout ($cb)
538 666
539Replace the current C<on_timeout> callback, or disables the callback (but 667=item $handle->on_rtimeout ($cb)
540not the timeout) if C<$cb> = C<undef>. See the C<timeout> constructor
541argument and method.
542 668
543=cut 669=item $handle->on_wtimeout ($cb)
544 670
545sub on_timeout { 671Replace the current C<on_timeout>, C<on_rtimeout> or C<on_wtimeout>
546 $_[0]{on_timeout} = $_[1]; 672callback, or disables the callback (but not the timeout) if C<$cb> =
547} 673C<undef>. See the C<timeout> constructor argument and method.
674
675=cut
676
677# see below
548 678
549=item $handle->autocork ($boolean) 679=item $handle->autocork ($boolean)
550 680
551Enables or disables the current autocork behaviour (see C<autocork> 681Enables or disables the current autocork behaviour (see C<autocork>
552constructor argument). Changes will only take effect on the next write. 682constructor argument). Changes will only take effect on the next write.
565=cut 695=cut
566 696
567sub no_delay { 697sub no_delay {
568 $_[0]{no_delay} = $_[1]; 698 $_[0]{no_delay} = $_[1];
569 699
700 setsockopt $_[0]{fh}, Socket::IPPROTO_TCP (), Socket::TCP_NODELAY (), int $_[1]
701 if $_[0]{fh};
702}
703
704=item $handle->keepalive ($boolean)
705
706Enables or disables the C<keepalive> setting (see constructor argument of
707the same name for details).
708
709=cut
710
711sub keepalive {
712 $_[0]{keepalive} = $_[1];
713
570 eval { 714 eval {
571 local $SIG{__DIE__}; 715 local $SIG{__DIE__};
572 setsockopt $_[0]{fh}, &Socket::IPPROTO_TCP, &Socket::TCP_NODELAY, int $_[1] 716 setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_KEEPALIVE (), int $_[1]
573 if $_[0]{fh}; 717 if $_[0]{fh};
574 }; 718 };
575} 719}
576 720
721=item $handle->oobinline ($boolean)
722
723Enables or disables the C<oobinline> setting (see constructor argument of
724the same name for details).
725
726=cut
727
728sub oobinline {
729 $_[0]{oobinline} = $_[1];
730
731 eval {
732 local $SIG{__DIE__};
733 setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_OOBINLINE (), int $_[1]
734 if $_[0]{fh};
735 };
736}
737
738=item $handle->keepalive ($boolean)
739
740Enables or disables the C<keepalive> setting (see constructor argument of
741the same name for details).
742
743=cut
744
745sub keepalive {
746 $_[0]{keepalive} = $_[1];
747
748 eval {
749 local $SIG{__DIE__};
750 setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_KEEPALIVE (), int $_[1]
751 if $_[0]{fh};
752 };
753}
754
577=item $handle->on_starttls ($cb) 755=item $handle->on_starttls ($cb)
578 756
579Replace the current C<on_starttls> callback (see the C<on_starttls> constructor argument). 757Replace the current C<on_starttls> callback (see the C<on_starttls> constructor argument).
580 758
581=cut 759=cut
588 766
589Replace the current C<on_stoptls> callback (see the C<on_stoptls> constructor argument). 767Replace the current C<on_stoptls> callback (see the C<on_stoptls> constructor argument).
590 768
591=cut 769=cut
592 770
593sub on_starttls { 771sub on_stoptls {
594 $_[0]{on_stoptls} = $_[1]; 772 $_[0]{on_stoptls} = $_[1];
595} 773}
596 774
775=item $handle->rbuf_max ($max_octets)
776
777Configures the C<rbuf_max> setting (C<undef> disables it).
778
779=item $handle->wbuf_max ($max_octets)
780
781Configures the C<wbuf_max> setting (C<undef> disables it).
782
783=cut
784
785sub rbuf_max {
786 $_[0]{rbuf_max} = $_[1];
787}
788
789sub wbuf_max {
790 $_[0]{wbuf_max} = $_[1];
791}
792
597############################################################################# 793#############################################################################
598 794
599=item $handle->timeout ($seconds) 795=item $handle->timeout ($seconds)
600 796
797=item $handle->rtimeout ($seconds)
798
799=item $handle->wtimeout ($seconds)
800
601Configures (or disables) the inactivity timeout. 801Configures (or disables) the inactivity timeout.
602 802
603=cut 803The timeout will be checked instantly, so this method might destroy the
804handle before it returns.
604 805
605sub timeout { 806=item $handle->timeout_reset
807
808=item $handle->rtimeout_reset
809
810=item $handle->wtimeout_reset
811
812Reset the activity timeout, as if data was received or sent.
813
814These methods are cheap to call.
815
816=cut
817
818for my $dir ("", "r", "w") {
819 my $timeout = "${dir}timeout";
820 my $tw = "_${dir}tw";
821 my $on_timeout = "on_${dir}timeout";
822 my $activity = "_${dir}activity";
823 my $cb;
824
825 *$on_timeout = sub {
826 $_[0]{$on_timeout} = $_[1];
827 };
828
829 *$timeout = sub {
606 my ($self, $timeout) = @_; 830 my ($self, $new_value) = @_;
607 831
832 $new_value >= 0
833 or Carp::croak "AnyEvent::Handle->$timeout called with negative timeout ($new_value), caught";
834
608 $self->{timeout} = $timeout; 835 $self->{$timeout} = $new_value;
609 $self->_timeout; 836 delete $self->{$tw}; &$cb;
610} 837 };
611 838
839 *{"${dir}timeout_reset"} = sub {
840 $_[0]{$activity} = AE::now;
841 };
842
843 # main workhorse:
612# reset the timeout watcher, as neccessary 844 # reset the timeout watcher, as neccessary
613# also check for time-outs 845 # also check for time-outs
614sub _timeout { 846 $cb = sub {
615 my ($self) = @_; 847 my ($self) = @_;
616 848
617 if ($self->{timeout} && $self->{fh}) { 849 if ($self->{$timeout} && $self->{fh}) {
618 my $NOW = AnyEvent->now; 850 my $NOW = AE::now;
619 851
620 # when would the timeout trigger? 852 # when would the timeout trigger?
621 my $after = $self->{_activity} + $self->{timeout} - $NOW; 853 my $after = $self->{$activity} + $self->{$timeout} - $NOW;
622 854
623 # now or in the past already? 855 # now or in the past already?
624 if ($after <= 0) { 856 if ($after <= 0) {
625 $self->{_activity} = $NOW; 857 $self->{$activity} = $NOW;
626 858
627 if ($self->{on_timeout}) { 859 if ($self->{$on_timeout}) {
628 $self->{on_timeout}($self); 860 $self->{$on_timeout}($self);
629 } else { 861 } else {
630 $self->_error (Errno::ETIMEDOUT); 862 $self->_error (Errno::ETIMEDOUT);
863 }
864
865 # callback could have changed timeout value, optimise
866 return unless $self->{$timeout};
867
868 # calculate new after
869 $after = $self->{$timeout};
631 } 870 }
632 871
633 # callback could have changed timeout value, optimise 872 Scalar::Util::weaken $self;
634 return unless $self->{timeout}; 873 return unless $self; # ->error could have destroyed $self
635 874
636 # calculate new after 875 $self->{$tw} ||= AE::timer $after, 0, sub {
637 $after = $self->{timeout}; 876 delete $self->{$tw};
877 $cb->($self);
878 };
879 } else {
880 delete $self->{$tw};
638 } 881 }
639
640 Scalar::Util::weaken $self;
641 return unless $self; # ->error could have destroyed $self
642
643 $self->{_tw} ||= AnyEvent->timer (after => $after, cb => sub {
644 delete $self->{_tw};
645 $self->_timeout;
646 });
647 } else {
648 delete $self->{_tw};
649 } 882 }
650} 883}
651 884
652############################################################################# 885#############################################################################
653 886
660 893
661The write queue is very simple: you can add data to its end, and 894The write queue is very simple: you can add data to its end, and
662AnyEvent::Handle will automatically try to get rid of it for you. 895AnyEvent::Handle will automatically try to get rid of it for you.
663 896
664When data could be written and the write buffer is shorter then the low 897When data could be written and the write buffer is shorter then the low
665water mark, the C<on_drain> callback will be invoked. 898water mark, the C<on_drain> callback will be invoked once.
666 899
667=over 4 900=over 4
668 901
669=item $handle->on_drain ($cb) 902=item $handle->on_drain ($cb)
670 903
671Sets the C<on_drain> callback or clears it (see the description of 904Sets the C<on_drain> callback or clears it (see the description of
672C<on_drain> in the constructor). 905C<on_drain> in the constructor).
673 906
907This method may invoke callbacks (and therefore the handle might be
908destroyed after it returns).
909
674=cut 910=cut
675 911
676sub on_drain { 912sub on_drain {
677 my ($self, $cb) = @_; 913 my ($self, $cb) = @_;
678 914
682 if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf}); 918 if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf});
683} 919}
684 920
685=item $handle->push_write ($data) 921=item $handle->push_write ($data)
686 922
687Queues the given scalar to be written. You can push as much data as you 923Queues the given scalar to be written. You can push as much data as
688want (only limited by the available memory), as C<AnyEvent::Handle> 924you want (only limited by the available memory and C<wbuf_max>), as
689buffers it independently of the kernel. 925C<AnyEvent::Handle> buffers it independently of the kernel.
926
927This method may invoke callbacks (and therefore the handle might be
928destroyed after it returns).
690 929
691=cut 930=cut
692 931
693sub _drain_wbuf { 932sub _drain_wbuf {
694 my ($self) = @_; 933 my ($self) = @_;
701 my $len = syswrite $self->{fh}, $self->{wbuf}; 940 my $len = syswrite $self->{fh}, $self->{wbuf};
702 941
703 if (defined $len) { 942 if (defined $len) {
704 substr $self->{wbuf}, 0, $len, ""; 943 substr $self->{wbuf}, 0, $len, "";
705 944
706 $self->{_activity} = AnyEvent->now; 945 $self->{_activity} = $self->{_wactivity} = AE::now;
707 946
708 $self->{on_drain}($self) 947 $self->{on_drain}($self)
709 if $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf}) 948 if $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf})
710 && $self->{on_drain}; 949 && $self->{on_drain};
711 950
717 956
718 # try to write data immediately 957 # try to write data immediately
719 $cb->() unless $self->{autocork}; 958 $cb->() unless $self->{autocork};
720 959
721 # if still data left in wbuf, we need to poll 960 # if still data left in wbuf, we need to poll
722 $self->{_ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb) 961 $self->{_ww} = AE::io $self->{fh}, 1, $cb
723 if length $self->{wbuf}; 962 if length $self->{wbuf};
963
964 if (
965 defined $self->{wbuf_max}
966 && $self->{wbuf_max} < length $self->{wbuf}
967 ) {
968 $self->_error (Errno::ENOSPC, 1), return;
969 }
724 }; 970 };
725} 971}
726 972
727our %WH; 973our %WH;
728 974
975# deprecated
729sub register_write_type($$) { 976sub register_write_type($$) {
730 $WH{$_[0]} = $_[1]; 977 $WH{$_[0]} = $_[1];
731} 978}
732 979
733sub push_write { 980sub push_write {
734 my $self = shift; 981 my $self = shift;
735 982
736 if (@_ > 1) { 983 if (@_ > 1) {
737 my $type = shift; 984 my $type = shift;
738 985
986 @_ = ($WH{$type} ||= _load_func "$type\::anyevent_write_type"
739 @_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write") 987 or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::push_write")
740 ->($self, @_); 988 ->($self, @_);
741 } 989 }
742 990
991 # we downgrade here to avoid hard-to-track-down bugs,
992 # and diagnose the problem earlier and better.
993
743 if ($self->{tls}) { 994 if ($self->{tls}) {
744 $self->{_tls_wbuf} .= $_[0]; 995 utf8::downgrade $self->{_tls_wbuf} .= $_[0];
745 996 &_dotls ($self) if $self->{fh};
746 &_dotls ($self);
747 } else { 997 } else {
748 $self->{wbuf} .= $_[0]; 998 utf8::downgrade $self->{wbuf} .= $_[0];
749 $self->_drain_wbuf if $self->{fh}; 999 $self->_drain_wbuf if $self->{fh};
750 } 1000 }
751} 1001}
752 1002
753=item $handle->push_write (type => @args) 1003=item $handle->push_write (type => @args)
754 1004
755Instead of formatting your data yourself, you can also let this module do 1005Instead of formatting your data yourself, you can also let this module
756the job by specifying a type and type-specific arguments. 1006do the job by specifying a type and type-specific arguments. You
1007can also specify the (fully qualified) name of a package, in which
1008case AnyEvent tries to load the package and then expects to find the
1009C<anyevent_write_type> function inside (see "custom write types", below).
757 1010
758Predefined types are (if you have ideas for additional types, feel free to 1011Predefined types are (if you have ideas for additional types, feel free to
759drop by and tell us): 1012drop by and tell us):
760 1013
761=over 4 1014=over 4
818Other languages could read single lines terminated by a newline and pass 1071Other languages could read single lines terminated by a newline and pass
819this line into their JSON decoder of choice. 1072this line into their JSON decoder of choice.
820 1073
821=cut 1074=cut
822 1075
1076sub json_coder() {
1077 eval { require JSON::XS; JSON::XS->new->utf8 }
1078 || do { require JSON; JSON->new->utf8 }
1079}
1080
823register_write_type json => sub { 1081register_write_type json => sub {
824 my ($self, $ref) = @_; 1082 my ($self, $ref) = @_;
825 1083
826 require JSON; 1084 my $json = $self->{json} ||= json_coder;
827 1085
828 $self->{json} ? $self->{json}->encode ($ref) 1086 $json->encode ($ref)
829 : JSON::encode_json ($ref)
830}; 1087};
831 1088
832=item storable => $reference 1089=item storable => $reference
833 1090
834Freezes the given reference using L<Storable> and writes it to the 1091Freezes the given reference using L<Storable> and writes it to the
837=cut 1094=cut
838 1095
839register_write_type storable => sub { 1096register_write_type storable => sub {
840 my ($self, $ref) = @_; 1097 my ($self, $ref) = @_;
841 1098
842 require Storable; 1099 require Storable unless $Storable::VERSION;
843 1100
844 pack "w/a*", Storable::nfreeze ($ref) 1101 pack "w/a*", Storable::nfreeze ($ref)
845}; 1102};
846 1103
847=back 1104=back
852before it was actually written. One way to do that is to replace your 1109before it was actually written. One way to do that is to replace your
853C<on_drain> handler by a callback that shuts down the socket (and set 1110C<on_drain> handler by a callback that shuts down the socket (and set
854C<low_water_mark> to C<0>). This method is a shorthand for just that, and 1111C<low_water_mark> to C<0>). This method is a shorthand for just that, and
855replaces the C<on_drain> callback with: 1112replaces the C<on_drain> callback with:
856 1113
857 sub { shutdown $_[0]{fh}, 1 } # for push_shutdown 1114 sub { shutdown $_[0]{fh}, 1 }
858 1115
859This simply shuts down the write side and signals an EOF condition to the 1116This simply shuts down the write side and signals an EOF condition to the
860the peer. 1117the peer.
861 1118
862You can rely on the normal read queue and C<on_eof> handling 1119You can rely on the normal read queue and C<on_eof> handling
863afterwards. This is the cleanest way to close a connection. 1120afterwards. This is the cleanest way to close a connection.
864 1121
1122This method may invoke callbacks (and therefore the handle might be
1123destroyed after it returns).
1124
865=cut 1125=cut
866 1126
867sub push_shutdown { 1127sub push_shutdown {
868 my ($self) = @_; 1128 my ($self) = @_;
869 1129
870 delete $self->{low_water_mark}; 1130 delete $self->{low_water_mark};
871 $self->on_drain (sub { shutdown $_[0]{fh}, 1 }); 1131 $self->on_drain (sub { shutdown $_[0]{fh}, 1 });
872} 1132}
873 1133
874=item AnyEvent::Handle::register_write_type type => $coderef->($handle, @args) 1134=item custom write types - Package::anyevent_write_type $handle, @args
875 1135
876This function (not method) lets you add your own types to C<push_write>. 1136Instead of one of the predefined types, you can also specify the name of
1137a package. AnyEvent will try to load the package and then expects to find
1138a function named C<anyevent_write_type> inside. If it isn't found, it
1139progressively tries to load the parent package until it either finds the
1140function (good) or runs out of packages (bad).
1141
877Whenever the given C<type> is used, C<push_write> will invoke the code 1142Whenever the given C<type> is used, C<push_write> will the function with
878reference with the handle object and the remaining arguments. 1143the handle object and the remaining arguments.
879 1144
880The code reference is supposed to return a single octet string that will 1145The function is supposed to return a single octet string that will be
881be appended to the write buffer. 1146appended to the write buffer, so you can mentally treat this function as a
1147"arguments to on-the-wire-format" converter.
882 1148
883Note that this is a function, and all types registered this way will be 1149Example: implement a custom write type C<join> that joins the remaining
884global, so try to use unique names. 1150arguments using the first one.
1151
1152 $handle->push_write (My::Type => " ", 1,2,3);
1153
1154 # uses the following package, which can be defined in the "My::Type" or in
1155 # the "My" modules to be auto-loaded, or just about anywhere when the
1156 # My::Type::anyevent_write_type is defined before invoking it.
1157
1158 package My::Type;
1159
1160 sub anyevent_write_type {
1161 my ($handle, $delim, @args) = @_;
1162
1163 join $delim, @args
1164 }
885 1165
886=cut 1166=cut
887 1167
888############################################################################# 1168#############################################################################
889 1169
898ways, the "simple" way, using only C<on_read> and the "complex" way, using 1178ways, the "simple" way, using only C<on_read> and the "complex" way, using
899a queue. 1179a queue.
900 1180
901In the simple case, you just install an C<on_read> callback and whenever 1181In the simple case, you just install an C<on_read> callback and whenever
902new data arrives, it will be called. You can then remove some data (if 1182new data arrives, it will be called. You can then remove some data (if
903enough is there) from the read buffer (C<< $handle->rbuf >>). Or you cna 1183enough is there) from the read buffer (C<< $handle->rbuf >>). Or you can
904leave the data there if you want to accumulate more (e.g. when only a 1184leave the data there if you want to accumulate more (e.g. when only a
905partial message has been received so far). 1185partial message has been received so far), or change the read queue with
1186e.g. C<push_read>.
906 1187
907In the more complex case, you want to queue multiple callbacks. In this 1188In the more complex case, you want to queue multiple callbacks. In this
908case, AnyEvent::Handle will call the first queued callback each time new 1189case, AnyEvent::Handle will call the first queued callback each time new
909data arrives (also the first time it is queued) and removes it when it has 1190data arrives (also the first time it is queued) and remove it when it has
910done its job (see C<push_read>, below). 1191done its job (see C<push_read>, below).
911 1192
912This way you can, for example, push three line-reads, followed by reading 1193This way you can, for example, push three line-reads, followed by reading
913a chunk of data, and AnyEvent::Handle will execute them in order. 1194a chunk of data, and AnyEvent::Handle will execute them in order.
914 1195
972 1253
973sub _drain_rbuf { 1254sub _drain_rbuf {
974 my ($self) = @_; 1255 my ($self) = @_;
975 1256
976 # avoid recursion 1257 # avoid recursion
977 return if exists $self->{_skip_drain_rbuf}; 1258 return if $self->{_skip_drain_rbuf};
978 local $self->{_skip_drain_rbuf} = 1; 1259 local $self->{_skip_drain_rbuf} = 1;
979
980 if (
981 defined $self->{rbuf_max}
982 && $self->{rbuf_max} < length $self->{rbuf}
983 ) {
984 $self->_error (Errno::ENOSPC, 1), return;
985 }
986 1260
987 while () { 1261 while () {
988 # we need to use a separate tls read buffer, as we must not receive data while 1262 # we need to use a separate tls read buffer, as we must not receive data while
989 # we are draining the buffer, and this can only happen with TLS. 1263 # we are draining the buffer, and this can only happen with TLS.
990 $self->{rbuf} .= delete $self->{_tls_rbuf} if exists $self->{_tls_rbuf}; 1264 $self->{rbuf} .= delete $self->{_tls_rbuf}
1265 if exists $self->{_tls_rbuf};
991 1266
992 my $len = length $self->{rbuf}; 1267 my $len = length $self->{rbuf};
993 1268
994 if (my $cb = shift @{ $self->{_queue} }) { 1269 if (my $cb = shift @{ $self->{_queue} }) {
995 unless ($cb->($self)) { 1270 unless ($cb->($self)) {
996 if ($self->{_eof}) { 1271 # no progress can be made
997 # no progress can be made (not enough data and no data forthcoming) 1272 # (not enough data and no data forthcoming)
998 $self->_error (Errno::EPIPE, 1), return; 1273 $self->_error (Errno::EPIPE, 1), return
999 } 1274 if $self->{_eof};
1000 1275
1001 unshift @{ $self->{_queue} }, $cb; 1276 unshift @{ $self->{_queue} }, $cb;
1002 last; 1277 last;
1003 } 1278 }
1004 } elsif ($self->{on_read}) { 1279 } elsif ($self->{on_read}) {
1024 last; 1299 last;
1025 } 1300 }
1026 } 1301 }
1027 1302
1028 if ($self->{_eof}) { 1303 if ($self->{_eof}) {
1029 if ($self->{on_eof}) { 1304 $self->{on_eof}
1030 $self->{on_eof}($self) 1305 ? $self->{on_eof}($self)
1031 } else {
1032 $self->_error (0, 1, "Unexpected end-of-file"); 1306 : $self->_error (0, 1, "Unexpected end-of-file");
1033 } 1307
1308 return;
1309 }
1310
1311 if (
1312 defined $self->{rbuf_max}
1313 && $self->{rbuf_max} < length $self->{rbuf}
1314 ) {
1315 $self->_error (Errno::ENOSPC, 1), return;
1034 } 1316 }
1035 1317
1036 # may need to restart read watcher 1318 # may need to restart read watcher
1037 unless ($self->{_rw}) { 1319 unless ($self->{_rw}) {
1038 $self->start_read 1320 $self->start_read
1044 1326
1045This replaces the currently set C<on_read> callback, or clears it (when 1327This replaces the currently set C<on_read> callback, or clears it (when
1046the new callback is C<undef>). See the description of C<on_read> in the 1328the new callback is C<undef>). See the description of C<on_read> in the
1047constructor. 1329constructor.
1048 1330
1331This method may invoke callbacks (and therefore the handle might be
1332destroyed after it returns).
1333
1049=cut 1334=cut
1050 1335
1051sub on_read { 1336sub on_read {
1052 my ($self, $cb) = @_; 1337 my ($self, $cb) = @_;
1053 1338
1055 $self->_drain_rbuf if $cb; 1340 $self->_drain_rbuf if $cb;
1056} 1341}
1057 1342
1058=item $handle->rbuf 1343=item $handle->rbuf
1059 1344
1060Returns the read buffer (as a modifiable lvalue). 1345Returns the read buffer (as a modifiable lvalue). You can also access the
1346read buffer directly as the C<< ->{rbuf} >> member, if you want (this is
1347much faster, and no less clean).
1061 1348
1062You can access the read buffer directly as the C<< ->{rbuf} >> 1349The only operation allowed on the read buffer (apart from looking at it)
1063member, if you want. However, the only operation allowed on the 1350is removing data from its beginning. Otherwise modifying or appending to
1064read buffer (apart from looking at it) is removing data from its 1351it is not allowed and will lead to hard-to-track-down bugs.
1065beginning. Otherwise modifying or appending to it is not allowed and will
1066lead to hard-to-track-down bugs.
1067 1352
1068NOTE: The read buffer should only be used or modified if the C<on_read>, 1353NOTE: The read buffer should only be used or modified in the C<on_read>
1069C<push_read> or C<unshift_read> methods are used. The other read methods 1354callback or when C<push_read> or C<unshift_read> are used with a single
1070automatically manage the read buffer. 1355callback (i.e. untyped). Typed C<push_read> and C<unshift_read> methods
1356will manage the read buffer on their own.
1071 1357
1072=cut 1358=cut
1073 1359
1074sub rbuf : lvalue { 1360sub rbuf : lvalue {
1075 $_[0]{rbuf} 1361 $_[0]{rbuf}
1092 1378
1093If enough data was available, then the callback must remove all data it is 1379If enough data was available, then the callback must remove all data it is
1094interested in (which can be none at all) and return a true value. After returning 1380interested in (which can be none at all) and return a true value. After returning
1095true, it will be removed from the queue. 1381true, it will be removed from the queue.
1096 1382
1383These methods may invoke callbacks (and therefore the handle might be
1384destroyed after it returns).
1385
1097=cut 1386=cut
1098 1387
1099our %RH; 1388our %RH;
1100 1389
1101sub register_read_type($$) { 1390sub register_read_type($$) {
1107 my $cb = pop; 1396 my $cb = pop;
1108 1397
1109 if (@_) { 1398 if (@_) {
1110 my $type = shift; 1399 my $type = shift;
1111 1400
1401 $cb = ($RH{$type} ||= _load_func "$type\::anyevent_read_type"
1112 $cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_read") 1402 or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::push_read")
1113 ->($self, $cb, @_); 1403 ->($self, $cb, @_);
1114 } 1404 }
1115 1405
1116 push @{ $self->{_queue} }, $cb; 1406 push @{ $self->{_queue} }, $cb;
1117 $self->_drain_rbuf; 1407 $self->_drain_rbuf;
1122 my $cb = pop; 1412 my $cb = pop;
1123 1413
1124 if (@_) { 1414 if (@_) {
1125 my $type = shift; 1415 my $type = shift;
1126 1416
1417 $cb = ($RH{$type} ||= _load_func "$type\::anyevent_read_type"
1127 $cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::unshift_read") 1418 or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::unshift_read")
1128 ->($self, $cb, @_); 1419 ->($self, $cb, @_);
1129 } 1420 }
1130
1131 1421
1132 unshift @{ $self->{_queue} }, $cb; 1422 unshift @{ $self->{_queue} }, $cb;
1133 $self->_drain_rbuf; 1423 $self->_drain_rbuf;
1134} 1424}
1135 1425
1137 1427
1138=item $handle->unshift_read (type => @args, $cb) 1428=item $handle->unshift_read (type => @args, $cb)
1139 1429
1140Instead of providing a callback that parses the data itself you can chose 1430Instead of providing a callback that parses the data itself you can chose
1141between a number of predefined parsing formats, for chunks of data, lines 1431between a number of predefined parsing formats, for chunks of data, lines
1142etc. 1432etc. You can also specify the (fully qualified) name of a package, in
1433which case AnyEvent tries to load the package and then expects to find the
1434C<anyevent_read_type> function inside (see "custom read types", below).
1143 1435
1144Predefined types are (if you have ideas for additional types, feel free to 1436Predefined types are (if you have ideas for additional types, feel free to
1145drop by and tell us): 1437drop by and tell us):
1146 1438
1147=over 4 1439=over 4
1153data. 1445data.
1154 1446
1155Example: read 2 bytes. 1447Example: read 2 bytes.
1156 1448
1157 $handle->push_read (chunk => 2, sub { 1449 $handle->push_read (chunk => 2, sub {
1158 warn "yay ", unpack "H*", $_[1]; 1450 say "yay " . unpack "H*", $_[1];
1159 }); 1451 });
1160 1452
1161=cut 1453=cut
1162 1454
1163register_read_type chunk => sub { 1455register_read_type chunk => sub {
1193 1485
1194register_read_type line => sub { 1486register_read_type line => sub {
1195 my ($self, $cb, $eol) = @_; 1487 my ($self, $cb, $eol) = @_;
1196 1488
1197 if (@_ < 3) { 1489 if (@_ < 3) {
1198 # this is more than twice as fast as the generic code below 1490 # this is faster then the generic code below
1199 sub { 1491 sub {
1200 $_[0]{rbuf} =~ s/^([^\015\012]*)(\015?\012)// or return; 1492 (my $pos = index $_[0]{rbuf}, "\012") >= 0
1493 or return;
1201 1494
1495 (my $str = substr $_[0]{rbuf}, 0, $pos + 1, "") =~ s/(\015?\012)\Z// or die;
1202 $cb->($_[0], $1, $2); 1496 $cb->($_[0], $str, "$1");
1203 1 1497 1
1204 } 1498 }
1205 } else { 1499 } else {
1206 $eol = quotemeta $eol unless ref $eol; 1500 $eol = quotemeta $eol unless ref $eol;
1207 $eol = qr|^(.*?)($eol)|s; 1501 $eol = qr|^(.*?)($eol)|s;
1208 1502
1209 sub { 1503 sub {
1210 $_[0]{rbuf} =~ s/$eol// or return; 1504 $_[0]{rbuf} =~ s/$eol// or return;
1211 1505
1212 $cb->($_[0], $1, $2); 1506 $cb->($_[0], "$1", "$2");
1213 1 1507 1
1214 } 1508 }
1215 } 1509 }
1216}; 1510};
1217 1511
1239the receive buffer when neither C<$accept> nor C<$reject> match, 1533the receive buffer when neither C<$accept> nor C<$reject> match,
1240and everything preceding and including the match will be accepted 1534and everything preceding and including the match will be accepted
1241unconditionally. This is useful to skip large amounts of data that you 1535unconditionally. This is useful to skip large amounts of data that you
1242know cannot be matched, so that the C<$accept> or C<$reject> regex do not 1536know cannot be matched, so that the C<$accept> or C<$reject> regex do not
1243have to start matching from the beginning. This is purely an optimisation 1537have to start matching from the beginning. This is purely an optimisation
1244and is usually worth only when you expect more than a few kilobytes. 1538and is usually worth it only when you expect more than a few kilobytes.
1245 1539
1246Example: expect a http header, which ends at C<\015\012\015\012>. Since we 1540Example: expect a http header, which ends at C<\015\012\015\012>. Since we
1247expect the header to be very large (it isn't in practise, but...), we use 1541expect the header to be very large (it isn't in practice, but...), we use
1248a skip regex to skip initial portions. The skip regex is tricky in that 1542a skip regex to skip initial portions. The skip regex is tricky in that
1249it only accepts something not ending in either \015 or \012, as these are 1543it only accepts something not ending in either \015 or \012, as these are
1250required for the accept regex. 1544required for the accept regex.
1251 1545
1252 $handle->push_read (regex => 1546 $handle->push_read (regex =>
1265 1559
1266 sub { 1560 sub {
1267 # accept 1561 # accept
1268 if ($$rbuf =~ $accept) { 1562 if ($$rbuf =~ $accept) {
1269 $data .= substr $$rbuf, 0, $+[0], ""; 1563 $data .= substr $$rbuf, 0, $+[0], "";
1270 $cb->($self, $data); 1564 $cb->($_[0], $data);
1271 return 1; 1565 return 1;
1272 } 1566 }
1273 1567
1274 # reject 1568 # reject
1275 if ($reject && $$rbuf =~ $reject) { 1569 if ($reject && $$rbuf =~ $reject) {
1276 $self->_error (Errno::EBADMSG); 1570 $_[0]->_error (Errno::EBADMSG);
1277 } 1571 }
1278 1572
1279 # skip 1573 # skip
1280 if ($skip && $$rbuf =~ $skip) { 1574 if ($skip && $$rbuf =~ $skip) {
1281 $data .= substr $$rbuf, 0, $+[0], ""; 1575 $data .= substr $$rbuf, 0, $+[0], "";
1297 my ($self, $cb) = @_; 1591 my ($self, $cb) = @_;
1298 1592
1299 sub { 1593 sub {
1300 unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) { 1594 unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
1301 if ($_[0]{rbuf} =~ /[^0-9]/) { 1595 if ($_[0]{rbuf} =~ /[^0-9]/) {
1302 $self->_error (Errno::EBADMSG); 1596 $_[0]->_error (Errno::EBADMSG);
1303 } 1597 }
1304 return; 1598 return;
1305 } 1599 }
1306 1600
1307 my $len = $1; 1601 my $len = $1;
1308 1602
1309 $self->unshift_read (chunk => $len, sub { 1603 $_[0]->unshift_read (chunk => $len, sub {
1310 my $string = $_[1]; 1604 my $string = $_[1];
1311 $_[0]->unshift_read (chunk => 1, sub { 1605 $_[0]->unshift_read (chunk => 1, sub {
1312 if ($_[1] eq ",") { 1606 if ($_[1] eq ",") {
1313 $cb->($_[0], $string); 1607 $cb->($_[0], $string);
1314 } else { 1608 } else {
1315 $self->_error (Errno::EBADMSG); 1609 $_[0]->_error (Errno::EBADMSG);
1316 } 1610 }
1317 }); 1611 });
1318 }); 1612 });
1319 1613
1320 1 1614 1
1387=cut 1681=cut
1388 1682
1389register_read_type json => sub { 1683register_read_type json => sub {
1390 my ($self, $cb) = @_; 1684 my ($self, $cb) = @_;
1391 1685
1392 my $json = $self->{json} ||= 1686 my $json = $self->{json} ||= json_coder;
1393 eval { require JSON::XS; JSON::XS->new->utf8 }
1394 || do { require JSON; JSON->new->utf8 };
1395 1687
1396 my $data; 1688 my $data;
1397 my $rbuf = \$self->{rbuf}; 1689 my $rbuf = \$self->{rbuf};
1398 1690
1399 sub { 1691 sub {
1400 my $ref = eval { $json->incr_parse ($self->{rbuf}) }; 1692 my $ref = eval { $json->incr_parse ($_[0]{rbuf}) };
1401 1693
1402 if ($ref) { 1694 if ($ref) {
1403 $self->{rbuf} = $json->incr_text; 1695 $_[0]{rbuf} = $json->incr_text;
1404 $json->incr_text = ""; 1696 $json->incr_text = "";
1405 $cb->($self, $ref); 1697 $cb->($_[0], $ref);
1406 1698
1407 1 1699 1
1408 } elsif ($@) { 1700 } elsif ($@) {
1409 # error case 1701 # error case
1410 $json->incr_skip; 1702 $json->incr_skip;
1411 1703
1412 $self->{rbuf} = $json->incr_text; 1704 $_[0]{rbuf} = $json->incr_text;
1413 $json->incr_text = ""; 1705 $json->incr_text = "";
1414 1706
1415 $self->_error (Errno::EBADMSG); 1707 $_[0]->_error (Errno::EBADMSG);
1416 1708
1417 () 1709 ()
1418 } else { 1710 } else {
1419 $self->{rbuf} = ""; 1711 $_[0]{rbuf} = "";
1420 1712
1421 () 1713 ()
1422 } 1714 }
1423 } 1715 }
1424}; 1716};
1434=cut 1726=cut
1435 1727
1436register_read_type storable => sub { 1728register_read_type storable => sub {
1437 my ($self, $cb) = @_; 1729 my ($self, $cb) = @_;
1438 1730
1439 require Storable; 1731 require Storable unless $Storable::VERSION;
1440 1732
1441 sub { 1733 sub {
1442 # when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method 1734 # when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
1443 defined (my $len = eval { unpack "w", $_[0]{rbuf} }) 1735 defined (my $len = eval { unpack "w", $_[0]{rbuf} })
1444 or return; 1736 or return;
1447 1739
1448 # bypass unshift if we already have the remaining chunk 1740 # bypass unshift if we already have the remaining chunk
1449 if ($format + $len <= length $_[0]{rbuf}) { 1741 if ($format + $len <= length $_[0]{rbuf}) {
1450 my $data = substr $_[0]{rbuf}, $format, $len; 1742 my $data = substr $_[0]{rbuf}, $format, $len;
1451 substr $_[0]{rbuf}, 0, $format + $len, ""; 1743 substr $_[0]{rbuf}, 0, $format + $len, "";
1744
1452 $cb->($_[0], Storable::thaw ($data)); 1745 eval { $cb->($_[0], Storable::thaw ($data)); 1 }
1746 or return $_[0]->_error (Errno::EBADMSG);
1453 } else { 1747 } else {
1454 # remove prefix 1748 # remove prefix
1455 substr $_[0]{rbuf}, 0, $format, ""; 1749 substr $_[0]{rbuf}, 0, $format, "";
1456 1750
1457 # read remaining chunk 1751 # read remaining chunk
1458 $_[0]->unshift_read (chunk => $len, sub { 1752 $_[0]->unshift_read (chunk => $len, sub {
1459 if (my $ref = eval { Storable::thaw ($_[1]) }) { 1753 eval { $cb->($_[0], Storable::thaw ($_[1])); 1 }
1460 $cb->($_[0], $ref);
1461 } else {
1462 $self->_error (Errno::EBADMSG); 1754 or $_[0]->_error (Errno::EBADMSG);
1463 }
1464 }); 1755 });
1465 } 1756 }
1466 1757
1467 1 1758 1
1468 } 1759 }
1469}; 1760};
1470 1761
1762=item tls_detect => $cb->($handle, $detect, $major, $minor)
1763
1764Checks the input stream for a valid SSL or TLS handshake TLSPaintext
1765record without consuming anything. Only SSL version 3 or higher
1766is handled, up to the fictituous protocol 4.x (but both SSL3+ and
1767SSL2-compatible framing is supported).
1768
1769If it detects that the input data is likely TLS, it calls the callback
1770with a true value for C<$detect> and the (on-wire) TLS version as second
1771and third argument (C<$major> is C<3>, and C<$minor> is 0..3 for SSL
17723.0, TLS 1.0, 1.1 and 1.2, respectively). If it detects the input to
1773be definitely not TLS, it calls the callback with a false value for
1774C<$detect>.
1775
1776The callback could use this information to decide whether or not to start
1777TLS negotiation.
1778
1779In all cases the data read so far is passed to the following read
1780handlers.
1781
1782Usually you want to use the C<tls_autostart> read type instead.
1783
1784If you want to design a protocol that works in the presence of TLS
1785dtection, make sure that any non-TLS data doesn't start with the octet 22
1786(ASCII SYN, 16 hex) or 128-255 (i.e. highest bit set). The checks this
1787read type does are a bit more strict, but might losen in the future to
1788accomodate protocol changes.
1789
1790This read type does not rely on L<AnyEvent::TLS> (and thus, not on
1791L<Net::SSLeay>).
1792
1793=item tls_autostart => $tls[, $tls_ctx]
1794
1795Tries to detect a valid SSL or TLS handshake. If one is detected, it tries
1796to start tls by calling C<starttls> with the given arguments.
1797
1798In practise, C<$tls> must be C<accept>, or a Net::SSLeay context that has
1799been configured to accept, as servers do not normally send a handshake on
1800their own and ths cannot be detected in this way.
1801
1802See C<tls_detect> above for more details.
1803
1804Example: give the client a chance to start TLS before accepting a text
1805line.
1806
1807 $hdl->push_read (tls_detect => "accept");
1808 $hdl->push_read (line => sub {
1809 print "received ", ($_[0]{tls} ? "encrypted" : "cleartext"), " <$_[1]>\n";
1810 });
1811
1812=cut
1813
1814register_read_type tls_detect => sub {
1815 my ($self, $cb) = @_;
1816
1817 sub {
1818 # this regex matches a full or partial tls record
1819 if (
1820 # ssl3+: type(22=handshake) major(=3) minor(any) length_hi
1821 $self->{rbuf} =~ /^(?:\z| \x16 (\z| [\x03\x04] (?:\z| . (?:\z| [\x00-\x40] ))))/xs
1822 # ssl2 comapatible: len_hi len_lo type(1) major minor dummy(forlength)
1823 or $self->{rbuf} =~ /^(?:\z| [\x80-\xff] (?:\z| . (?:\z| \x01 (\z| [\x03\x04] (?:\z| . (?:\z| . ))))))/xs
1824 ) {
1825 return if 3 != length $1; # partial match, can't decide yet
1826
1827 # full match, valid TLS record
1828 my ($major, $minor) = unpack "CC", $1;
1829 $cb->($self, "accept", $major + $minor * 0.1);
1830 } else {
1831 # mismatch == guaranteed not TLS
1832 $cb->($self, undef);
1833 }
1834
1835 1
1836 }
1837};
1838
1839register_read_type tls_autostart => sub {
1840 my ($self, @tls) = @_;
1841
1842 $RH{tls_detect}($self, sub {
1843 return unless $_[1];
1844 $_[0]->starttls (@tls);
1845 })
1846};
1847
1471=back 1848=back
1472 1849
1473=item AnyEvent::Handle::register_read_type type => $coderef->($handle, $cb, @args) 1850=item custom read types - Package::anyevent_read_type $handle, $cb, @args
1474 1851
1475This function (not method) lets you add your own types to C<push_read>. 1852Instead of one of the predefined types, you can also specify the name
1853of a package. AnyEvent will try to load the package and then expects to
1854find a function named C<anyevent_read_type> inside. If it isn't found, it
1855progressively tries to load the parent package until it either finds the
1856function (good) or runs out of packages (bad).
1476 1857
1477Whenever the given C<type> is used, C<push_read> will invoke the code 1858Whenever this type is used, C<push_read> will invoke the function with the
1478reference with the handle object, the callback and the remaining 1859handle object, the original callback and the remaining arguments.
1479arguments.
1480 1860
1481The code reference is supposed to return a callback (usually a closure) 1861The function is supposed to return a callback (usually a closure) that
1482that works as a plain read callback (see C<< ->push_read ($cb) >>). 1862works as a plain read callback (see C<< ->push_read ($cb) >>), so you can
1863mentally treat the function as a "configurable read type to read callback"
1864converter.
1483 1865
1484It should invoke the passed callback when it is done reading (remember to 1866It should invoke the original callback when it is done reading (remember
1485pass C<$handle> as first argument as all other callbacks do that). 1867to pass C<$handle> as first argument as all other callbacks do that,
1868although there is no strict requirement on this).
1486 1869
1487Note that this is a function, and all types registered this way will be
1488global, so try to use unique names.
1489
1490For examples, see the source of this module (F<perldoc -m AnyEvent::Handle>, 1870For examples, see the source of this module (F<perldoc -m
1491search for C<register_read_type>)). 1871AnyEvent::Handle>, search for C<register_read_type>)).
1492 1872
1493=item $handle->stop_read 1873=item $handle->stop_read
1494 1874
1495=item $handle->start_read 1875=item $handle->start_read
1496 1876
1502Note that AnyEvent::Handle will automatically C<start_read> for you when 1882Note that AnyEvent::Handle will automatically C<start_read> for you when
1503you change the C<on_read> callback or push/unshift a read callback, and it 1883you change the C<on_read> callback or push/unshift a read callback, and it
1504will automatically C<stop_read> for you when neither C<on_read> is set nor 1884will automatically C<stop_read> for you when neither C<on_read> is set nor
1505there are any read requests in the queue. 1885there are any read requests in the queue.
1506 1886
1507These methods will have no effect when in TLS mode (as TLS doesn't support 1887In older versions of this module (<= 5.3), these methods had no effect,
1508half-duplex connections). 1888as TLS does not support half-duplex connections. In current versions they
1889work as expected, as this behaviour is required to avoid certain resource
1890attacks, where the program would be forced to read (and buffer) arbitrary
1891amounts of data before being able to send some data. The drawback is that
1892some readings of the the SSL/TLS specifications basically require this
1893attack to be working, as SSL/TLS implementations might stall sending data
1894during a rehandshake.
1895
1896As a guideline, during the initial handshake, you should not stop reading,
1897and as a client, it might cause problems, depending on your application.
1509 1898
1510=cut 1899=cut
1511 1900
1512sub stop_read { 1901sub stop_read {
1513 my ($self) = @_; 1902 my ($self) = @_;
1514 1903
1515 delete $self->{_rw} unless $self->{tls}; 1904 delete $self->{_rw};
1516} 1905}
1517 1906
1518sub start_read { 1907sub start_read {
1519 my ($self) = @_; 1908 my ($self) = @_;
1520 1909
1521 unless ($self->{_rw} || $self->{_eof}) { 1910 unless ($self->{_rw} || $self->{_eof} || !$self->{fh}) {
1522 Scalar::Util::weaken $self; 1911 Scalar::Util::weaken $self;
1523 1912
1524 $self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub { 1913 $self->{_rw} = AE::io $self->{fh}, 0, sub {
1525 my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf}); 1914 my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf});
1526 my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf; 1915 my $len = sysread $self->{fh}, $$rbuf, $self->{read_size}, length $$rbuf;
1527 1916
1528 if ($len > 0) { 1917 if ($len > 0) {
1529 $self->{_activity} = AnyEvent->now; 1918 $self->{_activity} = $self->{_ractivity} = AE::now;
1530 1919
1531 if ($self->{tls}) { 1920 if ($self->{tls}) {
1532 Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf); 1921 Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf);
1533 1922
1534 &_dotls ($self); 1923 &_dotls ($self);
1535 } else { 1924 } else {
1536 $self->_drain_rbuf; 1925 $self->_drain_rbuf;
1537 } 1926 }
1538 1927
1928 if ($len == $self->{read_size}) {
1929 $self->{read_size} *= 2;
1930 $self->{read_size} = $self->{max_read_size} || MAX_READ_SIZE
1931 if $self->{read_size} > ($self->{max_read_size} || MAX_READ_SIZE);
1932 }
1933
1539 } elsif (defined $len) { 1934 } elsif (defined $len) {
1540 delete $self->{_rw}; 1935 delete $self->{_rw};
1541 $self->{_eof} = 1; 1936 $self->{_eof} = 1;
1542 $self->_drain_rbuf; 1937 $self->_drain_rbuf;
1543 1938
1544 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) { 1939 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
1545 return $self->_error ($!, 1); 1940 return $self->_error ($!, 1);
1546 } 1941 }
1547 }); 1942 };
1548 } 1943 }
1549} 1944}
1550 1945
1551our $ERROR_SYSCALL; 1946our $ERROR_SYSCALL;
1552our $ERROR_WANT_READ; 1947our $ERROR_WANT_READ;
1555 my ($self, $err) = @_; 1950 my ($self, $err) = @_;
1556 1951
1557 return $self->_error ($!, 1) 1952 return $self->_error ($!, 1)
1558 if $err == Net::SSLeay::ERROR_SYSCALL (); 1953 if $err == Net::SSLeay::ERROR_SYSCALL ();
1559 1954
1560 my $err =Net::SSLeay::ERR_error_string (Net::SSLeay::ERR_get_error ()); 1955 my $err = Net::SSLeay::ERR_error_string (Net::SSLeay::ERR_get_error ());
1561 1956
1562 # reduce error string to look less scary 1957 # reduce error string to look less scary
1563 $err =~ s/^error:[0-9a-fA-F]{8}:[^:]+:([^:]+):/\L$1: /; 1958 $err =~ s/^error:[0-9a-fA-F]{8}:[^:]+:([^:]+):/\L$1: /;
1564 1959
1565 if ($self->{_on_starttls}) { 1960 if ($self->{_on_starttls}) {
1619 && ($tmp != $ERROR_SYSCALL || $!); 2014 && ($tmp != $ERROR_SYSCALL || $!);
1620 2015
1621 while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) { 2016 while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) {
1622 $self->{wbuf} .= $tmp; 2017 $self->{wbuf} .= $tmp;
1623 $self->_drain_wbuf; 2018 $self->_drain_wbuf;
2019 $self->{tls} or return; # tls session might have gone away in callback
1624 } 2020 }
1625 2021
1626 $self->{_on_starttls} 2022 $self->{_on_starttls}
1627 and Net::SSLeay::state ($self->{tls}) == Net::SSLeay::ST_OK () 2023 and Net::SSLeay::state ($self->{tls}) == Net::SSLeay::ST_OK ()
1628 and (delete $self->{_on_starttls})->($self, 1, "TLS/SSL connection established"); 2024 and (delete $self->{_on_starttls})->($self, 1, "TLS/SSL connection established");
1630 2026
1631=item $handle->starttls ($tls[, $tls_ctx]) 2027=item $handle->starttls ($tls[, $tls_ctx])
1632 2028
1633Instead of starting TLS negotiation immediately when the AnyEvent::Handle 2029Instead of starting TLS negotiation immediately when the AnyEvent::Handle
1634object is created, you can also do that at a later time by calling 2030object is created, you can also do that at a later time by calling
1635C<starttls>. 2031C<starttls>. See the C<tls> constructor argument for general info.
1636 2032
1637Starting TLS is currently an asynchronous operation - when you push some 2033Starting TLS is currently an asynchronous operation - when you push some
1638write data and then call C<< ->starttls >> then TLS negotiation will start 2034write data and then call C<< ->starttls >> then TLS negotiation will start
1639immediately, after which the queued write data is then sent. 2035immediately, after which the queued write data is then sent. This might
2036change in future versions, so best make sure you have no outstanding write
2037data when calling this method.
1640 2038
1641The first argument is the same as the C<tls> constructor argument (either 2039The first argument is the same as the C<tls> constructor argument (either
1642C<"connect">, C<"accept"> or an existing Net::SSLeay object). 2040C<"connect">, C<"accept"> or an existing Net::SSLeay object).
1643 2041
1644The second argument is the optional C<AnyEvent::TLS> object that is used 2042The second argument is the optional C<AnyEvent::TLS> object that is used
1649The TLS connection object will end up in C<< $handle->{tls} >>, the TLS 2047The TLS connection object will end up in C<< $handle->{tls} >>, the TLS
1650context in C<< $handle->{tls_ctx} >> after this call and can be used or 2048context in C<< $handle->{tls_ctx} >> after this call and can be used or
1651changed to your liking. Note that the handshake might have already started 2049changed to your liking. Note that the handshake might have already started
1652when this function returns. 2050when this function returns.
1653 2051
1654If it an error to start a TLS handshake more than once per 2052Due to bugs in OpenSSL, it might or might not be possible to do multiple
1655AnyEvent::Handle object (this is due to bugs in OpenSSL). 2053handshakes on the same stream. It is best to not attempt to use the
2054stream after stopping TLS.
2055
2056This method may invoke callbacks (and therefore the handle might be
2057destroyed after it returns).
1656 2058
1657=cut 2059=cut
1658 2060
1659our %TLS_CACHE; #TODO not yet documented, should we? 2061our %TLS_CACHE; #TODO not yet documented, should we?
1660 2062
1661sub starttls { 2063sub starttls {
1662 my ($self, $ssl, $ctx) = @_; 2064 my ($self, $tls, $ctx) = @_;
1663 2065
1664 require Net::SSLeay; 2066 Carp::croak "It is an error to call starttls on an AnyEvent::Handle object while TLS is already active, caught"
1665
1666 Carp::croak "it is an error to call starttls more than once on an AnyEvent::Handle object"
1667 if $self->{tls}; 2067 if $self->{tls};
2068
2069 unless (defined $AnyEvent::TLS::VERSION) {
2070 eval {
2071 require Net::SSLeay;
2072 require AnyEvent::TLS;
2073 1
2074 } or return $self->_error (Errno::EPROTO, 1, "TLS support not available on this system");
2075 }
2076
2077 $self->{tls} = $tls;
2078 $self->{tls_ctx} = $ctx if @_ > 2;
2079
2080 return unless $self->{fh};
1668 2081
1669 $ERROR_SYSCALL = Net::SSLeay::ERROR_SYSCALL (); 2082 $ERROR_SYSCALL = Net::SSLeay::ERROR_SYSCALL ();
1670 $ERROR_WANT_READ = Net::SSLeay::ERROR_WANT_READ (); 2083 $ERROR_WANT_READ = Net::SSLeay::ERROR_WANT_READ ();
1671 2084
2085 $tls = delete $self->{tls};
1672 $ctx ||= $self->{tls_ctx}; 2086 $ctx = $self->{tls_ctx};
1673 2087
1674 local $Carp::CarpLevel = 1; # skip ourselves when creating a new context or session 2088 local $Carp::CarpLevel = 1; # skip ourselves when creating a new context or session
1675 2089
1676 if ("HASH" eq ref $ctx) { 2090 if ("HASH" eq ref $ctx) {
1677 require AnyEvent::TLS;
1678
1679 if ($ctx->{cache}) { 2091 if ($ctx->{cache}) {
1680 my $key = $ctx+0; 2092 my $key = $ctx+0;
1681 $ctx = $TLS_CACHE{$key} ||= new AnyEvent::TLS %$ctx; 2093 $ctx = $TLS_CACHE{$key} ||= new AnyEvent::TLS %$ctx;
1682 } else { 2094 } else {
1683 $ctx = new AnyEvent::TLS %$ctx; 2095 $ctx = new AnyEvent::TLS %$ctx;
1684 } 2096 }
1685 } 2097 }
1686 2098
1687 $self->{tls_ctx} = $ctx || TLS_CTX (); 2099 $self->{tls_ctx} = $ctx || TLS_CTX ();
1688 $self->{tls} = $ssl = $self->{tls_ctx}->_get_session ($ssl, $self, $self->{peername}); 2100 $self->{tls} = $tls = $self->{tls_ctx}->_get_session ($tls, $self, $self->{peername});
1689 2101
1690 # basically, this is deep magic (because SSL_read should have the same issues) 2102 # basically, this is deep magic (because SSL_read should have the same issues)
1691 # but the openssl maintainers basically said: "trust us, it just works". 2103 # but the openssl maintainers basically said: "trust us, it just works".
1692 # (unfortunately, we have to hardcode constants because the abysmally misdesigned 2104 # (unfortunately, we have to hardcode constants because the abysmally misdesigned
1693 # and mismaintained ssleay-module doesn't even offer them). 2105 # and mismaintained ssleay-module doesn't even offer them).
1700 # and we drive openssl fully in blocking mode here. Or maybe we don't - openssl seems to 2112 # and we drive openssl fully in blocking mode here. Or maybe we don't - openssl seems to
1701 # have identity issues in that area. 2113 # have identity issues in that area.
1702# Net::SSLeay::CTX_set_mode ($ssl, 2114# Net::SSLeay::CTX_set_mode ($ssl,
1703# (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1) 2115# (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)
1704# | (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2)); 2116# | (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2));
1705 Net::SSLeay::CTX_set_mode ($ssl, 1|2); 2117 Net::SSLeay::CTX_set_mode ($tls, 1|2);
1706 2118
1707 $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); 2119 $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1708 $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); 2120 $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1709 2121
2122 Net::SSLeay::BIO_write ($self->{_rbio}, $self->{rbuf});
2123 $self->{rbuf} = "";
2124
1710 Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio}); 2125 Net::SSLeay::set_bio ($tls, $self->{_rbio}, $self->{_wbio});
1711 2126
1712 $self->{_on_starttls} = sub { $_[0]{on_starttls}(@_) } 2127 $self->{_on_starttls} = sub { $_[0]{on_starttls}(@_) }
1713 if $self->{on_starttls}; 2128 if $self->{on_starttls};
1714 2129
1715 &_dotls; # need to trigger the initial handshake 2130 &_dotls; # need to trigger the initial handshake
1718 2133
1719=item $handle->stoptls 2134=item $handle->stoptls
1720 2135
1721Shuts down the SSL connection - this makes a proper EOF handshake by 2136Shuts down the SSL connection - this makes a proper EOF handshake by
1722sending a close notify to the other side, but since OpenSSL doesn't 2137sending a close notify to the other side, but since OpenSSL doesn't
1723support non-blocking shut downs, it is not possible to re-use the stream 2138support non-blocking shut downs, it is not guaranteed that you can re-use
1724afterwards. 2139the stream afterwards.
2140
2141This method may invoke callbacks (and therefore the handle might be
2142destroyed after it returns).
1725 2143
1726=cut 2144=cut
1727 2145
1728sub stoptls { 2146sub stoptls {
1729 my ($self) = @_; 2147 my ($self) = @_;
1730 2148
1731 if ($self->{tls}) { 2149 if ($self->{tls} && $self->{fh}) {
1732 Net::SSLeay::shutdown ($self->{tls}); 2150 Net::SSLeay::shutdown ($self->{tls});
1733 2151
1734 &_dotls; 2152 &_dotls;
1735 2153
1736# # we don't give a shit. no, we do, but we can't. no...#d# 2154# # we don't give a shit. no, we do, but we can't. no...#d#
1742sub _freetls { 2160sub _freetls {
1743 my ($self) = @_; 2161 my ($self) = @_;
1744 2162
1745 return unless $self->{tls}; 2163 return unless $self->{tls};
1746 2164
1747 $self->{tls_ctx}->_put_session (delete $self->{tls}); 2165 $self->{tls_ctx}->_put_session (delete $self->{tls})
2166 if $self->{tls} > 0;
1748 2167
1749 delete @$self{qw(_rbio _wbio _tls_wbuf _on_starttls)}; 2168 delete @$self{qw(_rbio _wbio _tls_wbuf _on_starttls)};
1750} 2169}
2170
2171=item $handle->resettls
2172
2173This rarely-used method simply resets and TLS state on the handle, usually
2174causing data loss.
2175
2176One case where it may be useful is when you want to skip over the data in
2177the stream but you are not interested in interpreting it, so data loss is
2178no concern.
2179
2180=cut
2181
2182*resettls = \&_freetls;
1751 2183
1752sub DESTROY { 2184sub DESTROY {
1753 my ($self) = @_; 2185 my ($self) = @_;
1754 2186
1755 &_freetls; 2187 &_freetls;
1760 my $fh = delete $self->{fh}; 2192 my $fh = delete $self->{fh};
1761 my $wbuf = delete $self->{wbuf}; 2193 my $wbuf = delete $self->{wbuf};
1762 2194
1763 my @linger; 2195 my @linger;
1764 2196
1765 push @linger, AnyEvent->io (fh => $fh, poll => "w", cb => sub { 2197 push @linger, AE::io $fh, 1, sub {
1766 my $len = syswrite $fh, $wbuf, length $wbuf; 2198 my $len = syswrite $fh, $wbuf, length $wbuf;
1767 2199
1768 if ($len > 0) { 2200 if ($len > 0) {
1769 substr $wbuf, 0, $len, ""; 2201 substr $wbuf, 0, $len, "";
1770 } else { 2202 } elsif (defined $len || ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK)) {
1771 @linger = (); # end 2203 @linger = (); # end
1772 } 2204 }
1773 }); 2205 };
1774 push @linger, AnyEvent->timer (after => $linger, cb => sub { 2206 push @linger, AE::timer $linger, 0, sub {
1775 @linger = (); 2207 @linger = ();
1776 }); 2208 };
1777 } 2209 }
1778} 2210}
1779 2211
1780=item $handle->destroy 2212=item $handle->destroy
1781 2213
1782Shuts down the handle object as much as possible - this call ensures that 2214Shuts down the handle object as much as possible - this call ensures that
1783no further callbacks will be invoked and as many resources as possible 2215no further callbacks will be invoked and as many resources as possible
1784will be freed. You must not call any methods on the object afterwards. 2216will be freed. Any method you will call on the handle object after
2217destroying it in this way will be silently ignored (and it will return the
2218empty list).
1785 2219
1786Normally, you can just "forget" any references to an AnyEvent::Handle 2220Normally, you can just "forget" any references to an AnyEvent::Handle
1787object and it will simply shut down. This works in fatal error and EOF 2221object and it will simply shut down. This works in fatal error and EOF
1788callbacks, as well as code outside. It does I<NOT> work in a read or write 2222callbacks, as well as code outside. It does I<NOT> work in a read or write
1789callback, so when you want to destroy the AnyEvent::Handle object from 2223callback, so when you want to destroy the AnyEvent::Handle object from
1803sub destroy { 2237sub destroy {
1804 my ($self) = @_; 2238 my ($self) = @_;
1805 2239
1806 $self->DESTROY; 2240 $self->DESTROY;
1807 %$self = (); 2241 %$self = ();
2242 bless $self, "AnyEvent::Handle::destroyed";
1808} 2243}
2244
2245sub AnyEvent::Handle::destroyed::AUTOLOAD {
2246 #nop
2247}
2248
2249=item $handle->destroyed
2250
2251Returns false as long as the handle hasn't been destroyed by a call to C<<
2252->destroy >>, true otherwise.
2253
2254Can be useful to decide whether the handle is still valid after some
2255callback possibly destroyed the handle. For example, C<< ->push_write >>,
2256C<< ->starttls >> and other methods can call user callbacks, which in turn
2257can destroy the handle, so work can be avoided by checking sometimes:
2258
2259 $hdl->starttls ("accept");
2260 return if $hdl->destroyed;
2261 $hdl->push_write (...
2262
2263Note that the call to C<push_write> will silently be ignored if the handle
2264has been destroyed, so often you can just ignore the possibility of the
2265handle being destroyed.
2266
2267=cut
2268
2269sub destroyed { 0 }
2270sub AnyEvent::Handle::destroyed::destroyed { 1 }
1809 2271
1810=item AnyEvent::Handle::TLS_CTX 2272=item AnyEvent::Handle::TLS_CTX
1811 2273
1812This function creates and returns the AnyEvent::TLS object used by default 2274This function creates and returns the AnyEvent::TLS object used by default
1813for TLS mode. 2275for TLS mode.
1841 2303
1842It is only safe to "forget" the reference inside EOF or error callbacks, 2304It is only safe to "forget" the reference inside EOF or error callbacks,
1843from within all other callbacks, you need to explicitly call the C<< 2305from within all other callbacks, you need to explicitly call the C<<
1844->destroy >> method. 2306->destroy >> method.
1845 2307
2308=item Why is my C<on_eof> callback never called?
2309
2310Probably because your C<on_error> callback is being called instead: When
2311you have outstanding requests in your read queue, then an EOF is
2312considered an error as you clearly expected some data.
2313
2314To avoid this, make sure you have an empty read queue whenever your handle
2315is supposed to be "idle" (i.e. connection closes are O.K.). You can set
2316an C<on_read> handler that simply pushes the first read requests in the
2317queue.
2318
2319See also the next question, which explains this in a bit more detail.
2320
2321=item How can I serve requests in a loop?
2322
2323Most protocols consist of some setup phase (authentication for example)
2324followed by a request handling phase, where the server waits for requests
2325and handles them, in a loop.
2326
2327There are two important variants: The first (traditional, better) variant
2328handles requests until the server gets some QUIT command, causing it to
2329close the connection first (highly desirable for a busy TCP server). A
2330client dropping the connection is an error, which means this variant can
2331detect an unexpected detection close.
2332
2333To handle this case, always make sure you have a non-empty read queue, by
2334pushing the "read request start" handler on it:
2335
2336 # we assume a request starts with a single line
2337 my @start_request; @start_request = (line => sub {
2338 my ($hdl, $line) = @_;
2339
2340 ... handle request
2341
2342 # push next request read, possibly from a nested callback
2343 $hdl->push_read (@start_request);
2344 });
2345
2346 # auth done, now go into request handling loop
2347 # now push the first @start_request
2348 $hdl->push_read (@start_request);
2349
2350By always having an outstanding C<push_read>, the handle always expects
2351some data and raises the C<EPIPE> error when the connction is dropped
2352unexpectedly.
2353
2354The second variant is a protocol where the client can drop the connection
2355at any time. For TCP, this means that the server machine may run out of
2356sockets easier, and in general, it means you cannot distinguish a protocl
2357failure/client crash from a normal connection close. Nevertheless, these
2358kinds of protocols are common (and sometimes even the best solution to the
2359problem).
2360
2361Having an outstanding read request at all times is possible if you ignore
2362C<EPIPE> errors, but this doesn't help with when the client drops the
2363connection during a request, which would still be an error.
2364
2365A better solution is to push the initial request read in an C<on_read>
2366callback. This avoids an error, as when the server doesn't expect data
2367(i.e. is idly waiting for the next request, an EOF will not raise an
2368error, but simply result in an C<on_eof> callback. It is also a bit slower
2369and simpler:
2370
2371 # auth done, now go into request handling loop
2372 $hdl->on_read (sub {
2373 my ($hdl) = @_;
2374
2375 # called each time we receive data but the read queue is empty
2376 # simply start read the request
2377
2378 $hdl->push_read (line => sub {
2379 my ($hdl, $line) = @_;
2380
2381 ... handle request
2382
2383 # do nothing special when the request has been handled, just
2384 # let the request queue go empty.
2385 });
2386 });
2387
1846=item I get different callback invocations in TLS mode/Why can't I pause 2388=item I get different callback invocations in TLS mode/Why can't I pause
1847reading? 2389reading?
1848 2390
1849Unlike, say, TCP, TLS connections do not consist of two independent 2391Unlike, say, TCP, TLS connections do not consist of two independent
1850communication channels, one for each direction. Or put differently. The 2392communication channels, one for each direction. Or put differently, the
1851read and write directions are not independent of each other: you cannot 2393read and write directions are not independent of each other: you cannot
1852write data unless you are also prepared to read, and vice versa. 2394write data unless you are also prepared to read, and vice versa.
1853 2395
1854This can mean than, in TLS mode, you might get C<on_error> or C<on_eof> 2396This means that, in TLS mode, you might get C<on_error> or C<on_eof>
1855callback invocations when you are not expecting any read data - the reason 2397callback invocations when you are not expecting any read data - the reason
1856is that AnyEvent::Handle always reads in TLS mode. 2398is that AnyEvent::Handle always reads in TLS mode.
1857 2399
1858During the connection, you have to make sure that you always have a 2400During the connection, you have to make sure that you always have a
1859non-empty read-queue, or an C<on_read> watcher. At the end of the 2401non-empty read-queue, or an C<on_read> watcher. At the end of the
1871 $handle->on_eof (undef); 2413 $handle->on_eof (undef);
1872 $handle->on_error (sub { 2414 $handle->on_error (sub {
1873 my $data = delete $_[0]{rbuf}; 2415 my $data = delete $_[0]{rbuf};
1874 }); 2416 });
1875 2417
2418Note that this example removes the C<rbuf> member from the handle object,
2419which is not normally allowed by the API. It is expressly permitted in
2420this case only, as the handle object needs to be destroyed afterwards.
2421
1876The reason to use C<on_error> is that TCP connections, due to latencies 2422The reason to use C<on_error> is that TCP connections, due to latencies
1877and packets loss, might get closed quite violently with an error, when in 2423and packets loss, might get closed quite violently with an error, when in
1878fact, all data has been received. 2424fact all data has been received.
1879 2425
1880It is usually better to use acknowledgements when transferring data, 2426It is usually better to use acknowledgements when transferring data,
1881to make sure the other side hasn't just died and you got the data 2427to make sure the other side hasn't just died and you got the data
1882intact. This is also one reason why so many internet protocols have an 2428intact. This is also one reason why so many internet protocols have an
1883explicit QUIT command. 2429explicit QUIT command.
1890C<low_water_mark> this will be called precisely when all data has been 2436C<low_water_mark> this will be called precisely when all data has been
1891written to the socket: 2437written to the socket:
1892 2438
1893 $handle->push_write (...); 2439 $handle->push_write (...);
1894 $handle->on_drain (sub { 2440 $handle->on_drain (sub {
1895 warn "all data submitted to the kernel\n"; 2441 AE::log debug => "All data submitted to the kernel.";
1896 undef $handle; 2442 undef $handle;
1897 }); 2443 });
1898 2444
1899If you just want to queue some data and then signal EOF to the other side, 2445If you just want to queue some data and then signal EOF to the other side,
1900consider using C<< ->push_shutdown >> instead. 2446consider using C<< ->push_shutdown >> instead.
1901 2447
1902=item I want to contact a TLS/SSL server, I don't care about security. 2448=item I want to contact a TLS/SSL server, I don't care about security.
1903 2449
1904If your TLS server is a pure TLS server (e.g. HTTPS) that only speaks TLS, 2450If your TLS server is a pure TLS server (e.g. HTTPS) that only speaks TLS,
1905simply connect to it and then create the AnyEvent::Handle with the C<tls> 2451connect to it and then create the AnyEvent::Handle with the C<tls>
1906parameter: 2452parameter:
1907 2453
1908 tcp_connect $host, $port, sub { 2454 tcp_connect $host, $port, sub {
1909 my ($fh) = @_; 2455 my ($fh) = @_;
1910 2456
1984When you have intermediate CA certificates that your clients might not 2530When you have intermediate CA certificates that your clients might not
1985know about, just append them to the C<cert_file>. 2531know about, just append them to the C<cert_file>.
1986 2532
1987=back 2533=back
1988 2534
1989
1990=head1 SUBCLASSING AnyEvent::Handle 2535=head1 SUBCLASSING AnyEvent::Handle
1991 2536
1992In many cases, you might want to subclass AnyEvent::Handle. 2537In many cases, you might want to subclass AnyEvent::Handle.
1993 2538
1994To make this easier, a given version of AnyEvent::Handle uses these 2539To make this easier, a given version of AnyEvent::Handle uses these
2010 2555
2011=item * all members not documented here and not prefixed with an underscore 2556=item * all members not documented here and not prefixed with an underscore
2012are free to use in subclasses. 2557are free to use in subclasses.
2013 2558
2014Of course, new versions of AnyEvent::Handle may introduce more "public" 2559Of course, new versions of AnyEvent::Handle may introduce more "public"
2015member variables, but thats just life, at least it is documented. 2560member variables, but that's just life. At least it is documented.
2016 2561
2017=back 2562=back
2018 2563
2019=head1 AUTHOR 2564=head1 AUTHOR
2020 2565
2021Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>. 2566Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>.
2022 2567
2023=cut 2568=cut
2024 2569
20251; # End of AnyEvent::Handle 25701
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