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Revision 1.170 by root, Sat Aug 1 09:14:54 2009 UTC vs.
Revision 1.241 by root, Fri Sep 5 22:17:26 2014 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 = 4.9;
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
96=over 4 114=over 4
97 115
98=item on_prepare => $cb->($handle) 116=item on_prepare => $cb->($handle)
99 117
100This (rarely used) callback is called before a new connection is 118This (rarely used) callback is called before a new connection is
101attempted, 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
102prepare the file handle with parameters required for the actual connect 121file handle with parameters required for the actual connect (as opposed to
103(as opposed to settings that can be changed when the connection is already 122settings that can be changed when the connection is already established).
104established).
105 123
106The return value of this callback should be the connect timeout value in 124The return value of this callback should be the connect timeout value in
107seconds (or C<0>, or C<undef>, or the empty list, to indicate the default 125seconds (or C<0>, or C<undef>, or the empty list, to indicate that the
108timeout is to be used). 126default timeout is to be used).
109 127
110=item on_connect => $cb->($handle, $host, $port, $retry->()) 128=item on_connect => $cb->($handle, $host, $port, $retry->())
111 129
112This callback is called when a connection has been successfully established. 130This callback is called when a connection has been successfully established.
113 131
114The actual numeric host and port (the socket peername) are passed as 132The peer's numeric host and port (the socket peername) are passed as
115parameters, together with a retry callback. 133parameters, together with a retry callback. At the time it is called the
134read and write queues, EOF status, TLS status and similar properties of
135the handle will have been reset.
116 136
137It is not allowed to use the read or write queues while the handle object
138is connecting.
139
117When, for some reason, the handle is not acceptable, then calling 140If, for some reason, the handle is not acceptable, calling C<$retry> will
118C<$retry> will continue with the next conenction target (in case of 141continue with the next connection target (in case of multi-homed hosts or
119multi-homed hosts or SRV records there can be multiple connection 142SRV records there can be multiple connection endpoints). The C<$retry>
120endpoints). 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
121tls 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.
122 146
123In most cases, ignoring the C<$retry> parameter is the way to go. 147In most cases, you should ignore the C<$retry> parameter.
124 148
125=item on_connect_error => $cb->($handle, $message) 149=item on_connect_error => $cb->($handle, $message)
126 150
127This callback is called when the conenction could not be 151This callback is called when the connection could not be
128established. C<$!> will contain the relevant error code, and C<$message> a 152established. C<$!> will contain the relevant error code, and C<$message> a
129message describing it (usually the same as C<"$!">). 153message describing it (usually the same as C<"$!">).
130 154
131If 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
132fatal error instead. 156fatal error instead.
135 159
136=item on_error => $cb->($handle, $fatal, $message) 160=item on_error => $cb->($handle, $fatal, $message)
137 161
138This is the error callback, which is called when, well, some error 162This is the error callback, which is called when, well, some error
139occured, such as not being able to resolve the hostname, failure to 163occured, such as not being able to resolve the hostname, failure to
140connect or a read error. 164connect, or a read error.
141 165
142Some errors are fatal (which is indicated by C<$fatal> being true). On 166Some errors are fatal (which is indicated by C<$fatal> being true). On
143fatal errors the handle object will be destroyed (by a call to C<< -> 167fatal errors the handle object will be destroyed (by a call to C<< ->
144destroy >>) after invoking the error callback (which means you are free to 168destroy >>) after invoking the error callback (which means you are free to
145examine the handle object). Examples of fatal errors are an EOF condition 169examine the handle object). Examples of fatal errors are an EOF condition
146with active (but unsatisifable) read watchers (C<EPIPE>) or I/O errors. In 170with active (but unsatisfiable) read watchers (C<EPIPE>) or I/O errors. In
147cases where the other side can close the connection at their will it is 171cases where the other side can close the connection at will, it is
148often easiest to not report C<EPIPE> errors in this callback. 172often easiest to not report C<EPIPE> errors in this callback.
149 173
150AnyEvent::Handle tries to find an appropriate error code for you to check 174AnyEvent::Handle tries to find an appropriate error code for you to check
151against, but in some cases (TLS errors), this does not work well. It is 175against, but in some cases (TLS errors), this does not work well.
152recommended to always output the C<$message> argument in human-readable
153error messages (it's usually the same as C<"$!">).
154 176
177If you report the error to the user, it is recommended to always output
178the C<$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
155Non-fatal errors can be retried by simply returning, but it is recommended 185Non-fatal errors can be retried by returning, but it is recommended
156to simply ignore this parameter and instead abondon the handle object 186to simply ignore this parameter and instead abondon the handle object
157when this callback is invoked. Examples of non-fatal errors are timeouts 187when this callback is invoked. Examples of non-fatal errors are timeouts
158C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>). 188C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>).
159 189
160On callback entrance, the value of C<$!> contains the operating system 190On entry to the callback, the value of C<$!> contains the operating
161error code (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT>, C<EBADMSG> or 191system error code (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT>, C<EBADMSG> or
162C<EPROTO>). 192C<EPROTO>).
163 193
164While 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
165you will not be notified of errors otherwise. The default simply calls 195you will not be notified of errors otherwise. The default just calls
166C<croak>. 196C<croak>.
167 197
168=item on_read => $cb->($handle) 198=item on_read => $cb->($handle)
169 199
170This sets the default read callback, which is called when data arrives 200This sets the default read callback, which is called when data arrives
175To 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 >>
176method or access the C<< $handle->{rbuf} >> member directly. Note that you 206method or access the C<< $handle->{rbuf} >> member directly. Note that you
177must not enlarge or modify the read buffer, you can only remove data at 207must not enlarge or modify the read buffer, you can only remove data at
178the beginning from it. 208the beginning from it.
179 209
210You can also call C<< ->push_read (...) >> or any other function that
211modifies the read queue. Or do both. Or ...
212
180When an EOF condition is detected then AnyEvent::Handle will first try to 213When an EOF condition is detected, AnyEvent::Handle will first try to
181feed all the remaining data to the queued callbacks and C<on_read> before 214feed all the remaining data to the queued callbacks and C<on_read> before
182calling the C<on_eof> callback. If no progress can be made, then a fatal 215calling the C<on_eof> callback. If no progress can be made, then a fatal
183error will be raised (with C<$!> set to C<EPIPE>). 216error will be raised (with C<$!> set to C<EPIPE>).
184 217
185Note that, unlike requests in the read queue, an C<on_read> callback 218Note that, unlike requests in the read queue, an C<on_read> callback
203If an EOF condition has been detected but no C<on_eof> callback has been 236If an EOF condition has been detected but no C<on_eof> callback has been
204set, then a fatal error will be raised with C<$!> set to <0>. 237set, then a fatal error will be raised with C<$!> set to <0>.
205 238
206=item on_drain => $cb->($handle) 239=item on_drain => $cb->($handle)
207 240
208This 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
209(or when the callback is set and the buffer is empty already). 242empty (and immediately when the handle object is created).
210 243
211To append to the write buffer, use the C<< ->push_write >> method. 244To append to the write buffer, use the C<< ->push_write >> method.
212 245
213This 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
214into 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
216memory 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
217the file when the write queue becomes empty. 250the file when the write queue becomes empty.
218 251
219=item timeout => $fractional_seconds 252=item timeout => $fractional_seconds
220 253
254=item rtimeout => $fractional_seconds
255
256=item wtimeout => $fractional_seconds
257
221If non-zero, then this enables an "inactivity" timeout: whenever this many 258If non-zero, then these enables an "inactivity" timeout: whenever this
222seconds pass without a successful read or write on the underlying file 259many seconds pass without a successful read or write on the underlying
223handle, 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
224missing, 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).
225 263
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
226Note 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
227any outstanding read or write requests: If you plan to keep the connection 272outstanding read or write requests: If you plan to keep the connection
228idle then you should disable the timout temporarily or ignore the timeout 273idle then you should disable the timeout temporarily or ignore the
229in the C<on_timeout> callback, in which case AnyEvent::Handle will simply 274timeout in the corresponding C<on_timeout> callback, in which case
230restart the timeout. 275AnyEvent::Handle will simply restart the timeout.
231 276
232Zero (the default) disables this timeout. 277Zero (the default) disables the corresponding timeout.
233 278
234=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)
235 284
236Called whenever the inactivity timeout passes. If you return from this 285Called whenever the inactivity timeout passes. If you return from this
237callback, 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,
238so this condition is not fatal in any way. 287so this condition is not fatal in any way.
239 288
247be 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
248(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
249amount 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
250isn't finished). 299isn't finished).
251 300
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
252=item autocork => <boolean> 316=item autocork => <boolean>
253 317
254When disabled (the default), then C<push_write> will try to immediately 318When disabled (the default), C<push_write> will try to immediately
255write 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
256a 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
257be inefficient if you write multiple small chunks (on the wire, this 321be inefficient if you write multiple small chunks (on the wire, this
258disadvantage is usually avoided by your kernel's nagle algorithm, see 322disadvantage is usually avoided by your kernel's nagle algorithm, see
259C<no_delay>, but this option can save costly syscalls). 323C<no_delay>, but this option can save costly syscalls).
260 324
261When enabled, then writes will always be queued till the next event loop 325When enabled, writes will always be queued till the next event loop
262iteration. This is efficient when you do many small writes per iteration, 326iteration. This is efficient when you do many small writes per iteration,
263but 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
264the write buffer often is full). It also increases write latency. 328the write buffer often is full). It also increases write latency.
265 329
266=item no_delay => <boolean> 330=item no_delay => <boolean>
270the Nagle algorithm, and usually it is beneficial. 334the Nagle algorithm, and usually it is beneficial.
271 335
272In 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
273accomplishd by setting this option to a true value. 337accomplishd by setting this option to a true value.
274 338
275The default is your opertaing system's default behaviour (most likely 339The default is your operating system's default behaviour (most likely
276enabled), 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.
277 373
278=item read_size => <bytes> 374=item read_size => <bytes>
279 375
280The default read block size (the amount of bytes this module will 376The initial read block size, the number of bytes this module will try
281try to read during each loop iteration, which affects memory 377to read during each loop iteration. Each handle object will consume
282requirements). 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.
283 388
284=item low_water_mark => <bytes> 389=item low_water_mark => <bytes>
285 390
286Sets 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
287buffer: 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
288considered empty. 393considered empty.
289 394
290Sometimes it can be beneficial (for performance reasons) to add data to 395Sometimes it can be beneficial (for performance reasons) to add data to
291the 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
292the operating system kernel usually buffers data as well, so the default 397the operating system kernel usually buffers data as well, so the default
293is good in almost all cases. 398is good in almost all cases.
294 399
295=item linger => <seconds> 400=item linger => <seconds>
296 401
297If non-zero (default: C<3600>), then the destructor of the 402If this is non-zero (default: C<3600>), the destructor of the
298AnyEvent::Handle object will check whether there is still outstanding 403AnyEvent::Handle object will check whether there is still outstanding
299write 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
300socket. No errors will be reported (this mostly matches how the operating 405socket. No errors will be reported (this mostly matches how the operating
301system treats outstanding data at socket close time). 406system treats outstanding data at socket close time).
302 407
309A string used to identify the remote site - usually the DNS hostname 414A string used to identify the remote site - usually the DNS hostname
310(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.
311 416
312Apart 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
313peername verification (see C<verify_peername> in L<AnyEvent::TLS>). This 418peername verification (see C<verify_peername> in L<AnyEvent::TLS>). This
314verification will be skipped when C<peername> is not specified or 419verification will be skipped when C<peername> is not specified or is
315C<undef>. 420C<undef>.
316 421
317=item tls => "accept" | "connect" | Net::SSLeay::SSL object 422=item tls => "accept" | "connect" | Net::SSLeay::SSL object
318 423
319When this parameter is given, it enables TLS (SSL) mode, that means 424When this parameter is given, it enables TLS (SSL) mode, that means
320AnyEvent 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
321established and will transparently encrypt/decrypt data afterwards. 426established and will transparently encrypt/decrypt data afterwards.
322 427
323All TLS protocol errors will be signalled as C<EPROTO>, with an 428All TLS protocol errors will be signalled as C<EPROTO>, with an
324appropriate error message. 429appropriate error message.
325 430
326TLS mode requires Net::SSLeay to be installed (it will be loaded 431TLS mode requires Net::SSLeay to be installed (it will be loaded
327automatically 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
328have 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
329to 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.
330 436
331Unlike 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
332C<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>
333mode. 439mode.
334 440
345B<IMPORTANT:> since Net::SSLeay "objects" are really only integers, 451B<IMPORTANT:> since Net::SSLeay "objects" are really only integers,
346passing 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
347happens 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
348segmentation fault. 454segmentation fault.
349 455
350See 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.
351 457
352=item tls_ctx => $anyevent_tls 458=item tls_ctx => $anyevent_tls
353 459
354Use 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
355(unless a connection object was specified directly). If this parameter is 461(unless a connection object was specified directly). If this
356missing, 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>.
357 464
358Instead 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
359=> 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
360new TLS context object. 467new TLS context object.
361 468
370 477
371TLS 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
372callback 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>.
373 480
374Without this callback, handshake failures lead to C<on_error> being 481Without this callback, handshake failures lead to C<on_error> being
375called, as normal. 482called as usual.
376 483
377Note 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
378need 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
379then call C<< ->starttls >> again. 486then call C<< ->starttls >> again.
380 487
381=item on_stoptls => $cb->($handle) 488=item on_stoptls => $cb->($handle)
382 489
389callback. 496callback.
390 497
391This callback will only be called on TLS shutdowns, not when the 498This callback will only be called on TLS shutdowns, not when the
392underlying handle signals EOF. 499underlying handle signals EOF.
393 500
394=item json => JSON or JSON::XS object 501=item json => L<JSON>, L<JSON::PP> or L<JSON::XS> object
395 502
396This is the json coder object used by the C<json> read and write types. 503This is the json coder object used by the C<json> read and write types.
397 504
398If you don't supply it, then AnyEvent::Handle will create and use a 505If you don't supply it, then AnyEvent::Handle will create and use a
399suitable one (on demand), which will write and expect UTF-8 encoded JSON 506suitable one (on demand), which will write and expect UTF-8 encoded
507JSON texts (either using L<JSON::XS> or L<JSON>). The written texts are
508guaranteed not to contain any newline character.
509
510For security reasons, this encoder will likely I<not> handle numbers and
511strings, only arrays and objects/hashes. The reason is that originally
512JSON was self-delimited, but Dougles Crockford thought it was a splendid
513idea to redefine JSON incompatibly, so this is no longer true.
514
515For protocols that used back-to-back JSON texts, this might lead to
516run-ins, where two or more JSON texts will be interpreted as one JSON
400texts. 517text.
401 518
519For this reason, if the default encoder uses L<JSON::XS>, it will default
520to not allowing anything but arrays and objects/hashes, at least for the
521forseeable future (it will change at some point). This might or might not
522be true for the L<JSON> module, so this might cause a security issue.
523
524If you depend on either behaviour, you should create your own json object
525and pass it in explicitly.
526
527=item cbor => L<CBOR::XS> object
528
529This is the cbor coder object used by the C<cbor> read and write types.
530
531If you don't supply it, then AnyEvent::Handle will create and use a
532suitable one (on demand), which will write CBOR without using extensions,
533if possible.
534
402Note that you are responsible to depend on the JSON module if you want to 535Note that you are responsible to depend on the L<CBOR::XS> module if you
403use this functionality, as AnyEvent does not have a dependency itself. 536want to use this functionality, as AnyEvent does not have a dependency on
537it itself.
404 538
405=back 539=back
406 540
407=cut 541=cut
408 542
430 $self->{connect}[0], 564 $self->{connect}[0],
431 $self->{connect}[1], 565 $self->{connect}[1],
432 sub { 566 sub {
433 my ($fh, $host, $port, $retry) = @_; 567 my ($fh, $host, $port, $retry) = @_;
434 568
569 delete $self->{_connect}; # no longer needed
570
435 if ($fh) { 571 if ($fh) {
436 $self->{fh} = $fh; 572 $self->{fh} = $fh;
437 573
438 delete $self->{_skip_drain_rbuf}; 574 delete $self->{_skip_drain_rbuf};
439 $self->_start; 575 $self->_start;
440 576
441 $self->{on_connect} 577 $self->{on_connect}
442 and $self->{on_connect}($self, $host, $port, sub { 578 and $self->{on_connect}($self, $host, $port, sub {
443 delete @$self{qw(fh _tw _ww _rw _eof _queue rbuf _wbuf tls _tls_rbuf _tls_wbuf)}; 579 delete @$self{qw(fh _tw _rtw _wtw _ww _rw _eof _queue rbuf _wbuf tls _tls_rbuf _tls_wbuf)};
444 $self->{_skip_drain_rbuf} = 1; 580 $self->{_skip_drain_rbuf} = 1;
445 &$retry; 581 &$retry;
446 }); 582 });
447 583
448 } else { 584 } else {
449 if ($self->{on_connect_error}) { 585 if ($self->{on_connect_error}) {
450 $self->{on_connect_error}($self, "$!"); 586 $self->{on_connect_error}($self, "$!");
451 $self->destroy; 587 $self->destroy if $self;
452 } else { 588 } else {
453 $self->_error ($!, 1); 589 $self->_error ($!, 1);
454 } 590 }
455 } 591 }
456 }, 592 },
457 sub { 593 sub {
458 local $self->{fh} = $_[0]; 594 local $self->{fh} = $_[0];
459 595
460 $self->{on_prepare} 596 $self->{on_prepare}
461 ? $self->{on_prepare}->($self) 597 ? $self->{on_prepare}->($self)
462 : () 598 : ()
463 } 599 }
464 ); 600 );
465 } 601 }
466 602
472} 608}
473 609
474sub _start { 610sub _start {
475 my ($self) = @_; 611 my ($self) = @_;
476 612
613 # too many clueless people try to use udp and similar sockets
614 # with AnyEvent::Handle, do them a favour.
615 my $type = getsockopt $self->{fh}, Socket::SOL_SOCKET (), Socket::SO_TYPE ();
616 Carp::croak "AnyEvent::Handle: only stream sockets supported, anything else will NOT work!"
617 if Socket::SOCK_STREAM () != (unpack "I", $type) && defined $type;
618
477 AnyEvent::Util::fh_nonblocking $self->{fh}, 1; 619 AnyEvent::Util::fh_nonblocking $self->{fh}, 1;
478 620
621 $self->{_activity} =
622 $self->{_ractivity} =
479 $self->{_activity} = AnyEvent->now; 623 $self->{_wactivity} = AE::now;
480 $self->_timeout;
481 624
625 $self->{read_size} ||= 2048;
626 $self->{max_read_size} = $self->{read_size}
627 if $self->{read_size} > ($self->{max_read_size} || MAX_READ_SIZE);
628
629 $self->timeout (delete $self->{timeout} ) if $self->{timeout};
630 $self->rtimeout (delete $self->{rtimeout} ) if $self->{rtimeout};
631 $self->wtimeout (delete $self->{wtimeout} ) if $self->{wtimeout};
632
482 $self->no_delay (delete $self->{no_delay}) if exists $self->{no_delay}; 633 $self->no_delay (delete $self->{no_delay} ) if exists $self->{no_delay} && $self->{no_delay};
634 $self->keepalive (delete $self->{keepalive}) if exists $self->{keepalive} && $self->{keepalive};
483 635
636 $self->oobinline (exists $self->{oobinline} ? delete $self->{oobinline} : 1);
637
484 $self->starttls (delete $self->{tls}, delete $self->{tls_ctx}) 638 $self->starttls (delete $self->{tls}, delete $self->{tls_ctx})
485 if $self->{tls}; 639 if $self->{tls};
486 640
487 $self->on_drain (delete $self->{on_drain}) if $self->{on_drain}; 641 $self->on_drain (delete $self->{on_drain} ) if $self->{on_drain};
488 642
489 $self->start_read 643 $self->start_read
490 if $self->{on_read} || @{ $self->{_queue} }; 644 if $self->{on_read} || @{ $self->{_queue} };
491 645
492 $self->_drain_wbuf; 646 $self->_drain_wbuf;
493} 647}
494
495#sub _shutdown {
496# my ($self) = @_;
497#
498# delete @$self{qw(_tw _rw _ww fh wbuf on_read _queue)};
499# $self->{_eof} = 1; # tell starttls et. al to stop trying
500#
501# &_freetls;
502#}
503 648
504sub _error { 649sub _error {
505 my ($self, $errno, $fatal, $message) = @_; 650 my ($self, $errno, $fatal, $message) = @_;
506 651
507 $! = $errno; 652 $! = $errno;
508 $message ||= "$!"; 653 $message ||= "$!";
509 654
510 if ($self->{on_error}) { 655 if ($self->{on_error}) {
511 $self->{on_error}($self, $fatal, $message); 656 $self->{on_error}($self, $fatal, $message);
512 $self->destroy if $fatal; 657 $self->destroy if $fatal;
513 } elsif ($self->{fh}) { 658 } elsif ($self->{fh} || $self->{connect}) {
514 $self->destroy; 659 $self->destroy;
515 Carp::croak "AnyEvent::Handle uncaught error: $message"; 660 Carp::croak "AnyEvent::Handle uncaught error: $message";
516 } 661 }
517} 662}
518 663
544 $_[0]{on_eof} = $_[1]; 689 $_[0]{on_eof} = $_[1];
545} 690}
546 691
547=item $handle->on_timeout ($cb) 692=item $handle->on_timeout ($cb)
548 693
549Replace the current C<on_timeout> callback, or disables the callback (but 694=item $handle->on_rtimeout ($cb)
550not the timeout) if C<$cb> = C<undef>. See the C<timeout> constructor
551argument and method.
552 695
553=cut 696=item $handle->on_wtimeout ($cb)
554 697
555sub on_timeout { 698Replace the current C<on_timeout>, C<on_rtimeout> or C<on_wtimeout>
556 $_[0]{on_timeout} = $_[1]; 699callback, or disables the callback (but not the timeout) if C<$cb> =
557} 700C<undef>. See the C<timeout> constructor argument and method.
701
702=cut
703
704# see below
558 705
559=item $handle->autocork ($boolean) 706=item $handle->autocork ($boolean)
560 707
561Enables or disables the current autocork behaviour (see C<autocork> 708Enables or disables the current autocork behaviour (see C<autocork>
562constructor argument). Changes will only take effect on the next write. 709constructor argument). Changes will only take effect on the next write.
575=cut 722=cut
576 723
577sub no_delay { 724sub no_delay {
578 $_[0]{no_delay} = $_[1]; 725 $_[0]{no_delay} = $_[1];
579 726
727 setsockopt $_[0]{fh}, Socket::IPPROTO_TCP (), Socket::TCP_NODELAY (), int $_[1]
728 if $_[0]{fh};
729}
730
731=item $handle->keepalive ($boolean)
732
733Enables or disables the C<keepalive> setting (see constructor argument of
734the same name for details).
735
736=cut
737
738sub keepalive {
739 $_[0]{keepalive} = $_[1];
740
580 eval { 741 eval {
581 local $SIG{__DIE__}; 742 local $SIG{__DIE__};
582 setsockopt $_[0]{fh}, &Socket::IPPROTO_TCP, &Socket::TCP_NODELAY, int $_[1] 743 setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_KEEPALIVE (), int $_[1]
583 if $_[0]{fh}; 744 if $_[0]{fh};
584 }; 745 };
585} 746}
586 747
748=item $handle->oobinline ($boolean)
749
750Enables or disables the C<oobinline> setting (see constructor argument of
751the same name for details).
752
753=cut
754
755sub oobinline {
756 $_[0]{oobinline} = $_[1];
757
758 eval {
759 local $SIG{__DIE__};
760 setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_OOBINLINE (), int $_[1]
761 if $_[0]{fh};
762 };
763}
764
765=item $handle->keepalive ($boolean)
766
767Enables or disables the C<keepalive> setting (see constructor argument of
768the same name for details).
769
770=cut
771
772sub keepalive {
773 $_[0]{keepalive} = $_[1];
774
775 eval {
776 local $SIG{__DIE__};
777 setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_KEEPALIVE (), int $_[1]
778 if $_[0]{fh};
779 };
780}
781
587=item $handle->on_starttls ($cb) 782=item $handle->on_starttls ($cb)
588 783
589Replace the current C<on_starttls> callback (see the C<on_starttls> constructor argument). 784Replace the current C<on_starttls> callback (see the C<on_starttls> constructor argument).
590 785
591=cut 786=cut
598 793
599Replace the current C<on_stoptls> callback (see the C<on_stoptls> constructor argument). 794Replace the current C<on_stoptls> callback (see the C<on_stoptls> constructor argument).
600 795
601=cut 796=cut
602 797
603sub on_starttls { 798sub on_stoptls {
604 $_[0]{on_stoptls} = $_[1]; 799 $_[0]{on_stoptls} = $_[1];
605} 800}
606 801
607=item $handle->rbuf_max ($max_octets) 802=item $handle->rbuf_max ($max_octets)
608 803
609Configures the C<rbuf_max> setting (C<undef> disables it). 804Configures the C<rbuf_max> setting (C<undef> disables it).
805
806=item $handle->wbuf_max ($max_octets)
807
808Configures the C<wbuf_max> setting (C<undef> disables it).
610 809
611=cut 810=cut
612 811
613sub rbuf_max { 812sub rbuf_max {
614 $_[0]{rbuf_max} = $_[1]; 813 $_[0]{rbuf_max} = $_[1];
615} 814}
616 815
816sub wbuf_max {
817 $_[0]{wbuf_max} = $_[1];
818}
819
617############################################################################# 820#############################################################################
618 821
619=item $handle->timeout ($seconds) 822=item $handle->timeout ($seconds)
620 823
824=item $handle->rtimeout ($seconds)
825
826=item $handle->wtimeout ($seconds)
827
621Configures (or disables) the inactivity timeout. 828Configures (or disables) the inactivity timeout.
622 829
623=cut 830The timeout will be checked instantly, so this method might destroy the
831handle before it returns.
624 832
625sub timeout { 833=item $handle->timeout_reset
834
835=item $handle->rtimeout_reset
836
837=item $handle->wtimeout_reset
838
839Reset the activity timeout, as if data was received or sent.
840
841These methods are cheap to call.
842
843=cut
844
845for my $dir ("", "r", "w") {
846 my $timeout = "${dir}timeout";
847 my $tw = "_${dir}tw";
848 my $on_timeout = "on_${dir}timeout";
849 my $activity = "_${dir}activity";
850 my $cb;
851
852 *$on_timeout = sub {
853 $_[0]{$on_timeout} = $_[1];
854 };
855
856 *$timeout = sub {
626 my ($self, $timeout) = @_; 857 my ($self, $new_value) = @_;
627 858
859 $new_value >= 0
860 or Carp::croak "AnyEvent::Handle->$timeout called with negative timeout ($new_value), caught";
861
628 $self->{timeout} = $timeout; 862 $self->{$timeout} = $new_value;
629 $self->_timeout; 863 delete $self->{$tw}; &$cb;
630} 864 };
631 865
866 *{"${dir}timeout_reset"} = sub {
867 $_[0]{$activity} = AE::now;
868 };
869
870 # main workhorse:
632# reset the timeout watcher, as neccessary 871 # reset the timeout watcher, as neccessary
633# also check for time-outs 872 # also check for time-outs
634sub _timeout { 873 $cb = sub {
635 my ($self) = @_; 874 my ($self) = @_;
636 875
637 if ($self->{timeout} && $self->{fh}) { 876 if ($self->{$timeout} && $self->{fh}) {
638 my $NOW = AnyEvent->now; 877 my $NOW = AE::now;
639 878
640 # when would the timeout trigger? 879 # when would the timeout trigger?
641 my $after = $self->{_activity} + $self->{timeout} - $NOW; 880 my $after = $self->{$activity} + $self->{$timeout} - $NOW;
642 881
643 # now or in the past already? 882 # now or in the past already?
644 if ($after <= 0) { 883 if ($after <= 0) {
645 $self->{_activity} = $NOW; 884 $self->{$activity} = $NOW;
646 885
647 if ($self->{on_timeout}) { 886 if ($self->{$on_timeout}) {
648 $self->{on_timeout}($self); 887 $self->{$on_timeout}($self);
649 } else { 888 } else {
650 $self->_error (Errno::ETIMEDOUT); 889 $self->_error (Errno::ETIMEDOUT);
890 }
891
892 # callback could have changed timeout value, optimise
893 return unless $self->{$timeout};
894
895 # calculate new after
896 $after = $self->{$timeout};
651 } 897 }
652 898
653 # callback could have changed timeout value, optimise 899 Scalar::Util::weaken $self;
654 return unless $self->{timeout}; 900 return unless $self; # ->error could have destroyed $self
655 901
656 # calculate new after 902 $self->{$tw} ||= AE::timer $after, 0, sub {
657 $after = $self->{timeout}; 903 delete $self->{$tw};
904 $cb->($self);
905 };
906 } else {
907 delete $self->{$tw};
658 } 908 }
659
660 Scalar::Util::weaken $self;
661 return unless $self; # ->error could have destroyed $self
662
663 $self->{_tw} ||= AnyEvent->timer (after => $after, cb => sub {
664 delete $self->{_tw};
665 $self->_timeout;
666 });
667 } else {
668 delete $self->{_tw};
669 } 909 }
670} 910}
671 911
672############################################################################# 912#############################################################################
673 913
680 920
681The write queue is very simple: you can add data to its end, and 921The write queue is very simple: you can add data to its end, and
682AnyEvent::Handle will automatically try to get rid of it for you. 922AnyEvent::Handle will automatically try to get rid of it for you.
683 923
684When data could be written and the write buffer is shorter then the low 924When data could be written and the write buffer is shorter then the low
685water mark, the C<on_drain> callback will be invoked. 925water mark, the C<on_drain> callback will be invoked once.
686 926
687=over 4 927=over 4
688 928
689=item $handle->on_drain ($cb) 929=item $handle->on_drain ($cb)
690 930
691Sets the C<on_drain> callback or clears it (see the description of 931Sets the C<on_drain> callback or clears it (see the description of
692C<on_drain> in the constructor). 932C<on_drain> in the constructor).
693 933
934This method may invoke callbacks (and therefore the handle might be
935destroyed after it returns).
936
694=cut 937=cut
695 938
696sub on_drain { 939sub on_drain {
697 my ($self, $cb) = @_; 940 my ($self, $cb) = @_;
698 941
702 if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf}); 945 if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf});
703} 946}
704 947
705=item $handle->push_write ($data) 948=item $handle->push_write ($data)
706 949
707Queues the given scalar to be written. You can push as much data as you 950Queues the given scalar to be written. You can push as much data as
708want (only limited by the available memory), as C<AnyEvent::Handle> 951you want (only limited by the available memory and C<wbuf_max>), as
709buffers it independently of the kernel. 952C<AnyEvent::Handle> buffers it independently of the kernel.
953
954This method may invoke callbacks (and therefore the handle might be
955destroyed after it returns).
710 956
711=cut 957=cut
712 958
713sub _drain_wbuf { 959sub _drain_wbuf {
714 my ($self) = @_; 960 my ($self) = @_;
721 my $len = syswrite $self->{fh}, $self->{wbuf}; 967 my $len = syswrite $self->{fh}, $self->{wbuf};
722 968
723 if (defined $len) { 969 if (defined $len) {
724 substr $self->{wbuf}, 0, $len, ""; 970 substr $self->{wbuf}, 0, $len, "";
725 971
726 $self->{_activity} = AnyEvent->now; 972 $self->{_activity} = $self->{_wactivity} = AE::now;
727 973
728 $self->{on_drain}($self) 974 $self->{on_drain}($self)
729 if $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf}) 975 if $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf})
730 && $self->{on_drain}; 976 && $self->{on_drain};
731 977
737 983
738 # try to write data immediately 984 # try to write data immediately
739 $cb->() unless $self->{autocork}; 985 $cb->() unless $self->{autocork};
740 986
741 # if still data left in wbuf, we need to poll 987 # if still data left in wbuf, we need to poll
742 $self->{_ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb) 988 $self->{_ww} = AE::io $self->{fh}, 1, $cb
743 if length $self->{wbuf}; 989 if length $self->{wbuf};
990
991 if (
992 defined $self->{wbuf_max}
993 && $self->{wbuf_max} < length $self->{wbuf}
994 ) {
995 $self->_error (Errno::ENOSPC, 1), return;
996 }
744 }; 997 };
745} 998}
746 999
747our %WH; 1000our %WH;
748 1001
1002# deprecated
749sub register_write_type($$) { 1003sub register_write_type($$) {
750 $WH{$_[0]} = $_[1]; 1004 $WH{$_[0]} = $_[1];
751} 1005}
752 1006
753sub push_write { 1007sub push_write {
754 my $self = shift; 1008 my $self = shift;
755 1009
756 if (@_ > 1) { 1010 if (@_ > 1) {
757 my $type = shift; 1011 my $type = shift;
758 1012
1013 @_ = ($WH{$type} ||= _load_func "$type\::anyevent_write_type"
759 @_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write") 1014 or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::push_write")
760 ->($self, @_); 1015 ->($self, @_);
761 } 1016 }
762 1017
1018 # we downgrade here to avoid hard-to-track-down bugs,
1019 # and diagnose the problem earlier and better.
1020
763 if ($self->{tls}) { 1021 if ($self->{tls}) {
764 $self->{_tls_wbuf} .= $_[0]; 1022 utf8::downgrade $self->{_tls_wbuf} .= $_[0];
765 &_dotls ($self) if $self->{fh}; 1023 &_dotls ($self) if $self->{fh};
766 } else { 1024 } else {
767 $self->{wbuf} .= $_[0]; 1025 utf8::downgrade $self->{wbuf} .= $_[0];
768 $self->_drain_wbuf if $self->{fh}; 1026 $self->_drain_wbuf if $self->{fh};
769 } 1027 }
770} 1028}
771 1029
772=item $handle->push_write (type => @args) 1030=item $handle->push_write (type => @args)
773 1031
774Instead of formatting your data yourself, you can also let this module do 1032Instead of formatting your data yourself, you can also let this module
775the job by specifying a type and type-specific arguments. 1033do the job by specifying a type and type-specific arguments. You
1034can also specify the (fully qualified) name of a package, in which
1035case AnyEvent tries to load the package and then expects to find the
1036C<anyevent_write_type> function inside (see "custom write types", below).
776 1037
777Predefined types are (if you have ideas for additional types, feel free to 1038Predefined types are (if you have ideas for additional types, feel free to
778drop by and tell us): 1039drop by and tell us):
779 1040
780=over 4 1041=over 4
811 1072
812Encodes the given hash or array reference into a JSON object. Unless you 1073Encodes the given hash or array reference into a JSON object. Unless you
813provide your own JSON object, this means it will be encoded to JSON text 1074provide your own JSON object, this means it will be encoded to JSON text
814in UTF-8. 1075in UTF-8.
815 1076
1077The default encoder might or might not handle every type of JSON value -
1078it might be limited to arrays and objects for security reasons. See the
1079C<json> constructor attribute for more details.
1080
816JSON objects (and arrays) are self-delimiting, so you can write JSON at 1081JSON objects (and arrays) are self-delimiting, so if you only use arrays
817one end of a handle and read them at the other end without using any 1082and hashes, you can write JSON at one end of a handle and read them at the
818additional framing. 1083other end without using any additional framing.
819 1084
820The generated JSON text is guaranteed not to contain any newlines: While 1085The JSON text generated by the default encoder is guaranteed not to
821this module doesn't need delimiters after or between JSON texts to be 1086contain any newlines: While this module doesn't need delimiters after or
822able to read them, many other languages depend on that. 1087between JSON texts to be able to read them, many other languages depend on
1088them.
823 1089
824A simple RPC protocol that interoperates easily with others is to send 1090A simple RPC protocol that interoperates easily with other languages is
825JSON arrays (or objects, although arrays are usually the better choice as 1091to send JSON arrays (or objects, although arrays are usually the better
826they mimic how function argument passing works) and a newline after each 1092choice as they mimic how function argument passing works) and a newline
827JSON text: 1093after each JSON text:
828 1094
829 $handle->push_write (json => ["method", "arg1", "arg2"]); # whatever 1095 $handle->push_write (json => ["method", "arg1", "arg2"]); # whatever
830 $handle->push_write ("\012"); 1096 $handle->push_write ("\012");
831 1097
832An AnyEvent::Handle receiver would simply use the C<json> read type and 1098An AnyEvent::Handle receiver would simply use the C<json> read type and
835 $handle->push_read (json => sub { my $array = $_[1]; ... }); 1101 $handle->push_read (json => sub { my $array = $_[1]; ... });
836 1102
837Other languages could read single lines terminated by a newline and pass 1103Other languages could read single lines terminated by a newline and pass
838this line into their JSON decoder of choice. 1104this line into their JSON decoder of choice.
839 1105
1106=item cbor => $perl_scalar
1107
1108Encodes the given scalar into a CBOR value. Unless you provide your own
1109L<CBOR::XS> object, this means it will be encoded to a CBOR string not
1110using any extensions, if possible.
1111
1112CBOR values are self-delimiting, so you can write CBOR at one end of
1113a handle and read them at the other end without using any additional
1114framing.
1115
1116A simple nd very very fast RPC protocol that interoperates with
1117other languages is to send CBOR and receive CBOR values (arrays are
1118recommended):
1119
1120 $handle->push_write (cbor => ["method", "arg1", "arg2"]); # whatever
1121
1122An AnyEvent::Handle receiver would simply use the C<cbor> read type:
1123
1124 $handle->push_read (cbor => sub { my $array = $_[1]; ... });
1125
840=cut 1126=cut
1127
1128sub json_coder() {
1129 eval { require JSON::XS; JSON::XS->new->utf8 }
1130 || do { require JSON::PP; JSON::PP->new->utf8 }
1131}
841 1132
842register_write_type json => sub { 1133register_write_type json => sub {
843 my ($self, $ref) = @_; 1134 my ($self, $ref) = @_;
844 1135
845 require JSON; 1136 ($self->{json} ||= json_coder)
1137 ->encode ($ref)
1138};
846 1139
847 $self->{json} ? $self->{json}->encode ($ref) 1140sub cbor_coder() {
848 : JSON::encode_json ($ref) 1141 require CBOR::XS;
1142 CBOR::XS->new
1143}
1144
1145register_write_type cbor => sub {
1146 my ($self, $scalar) = @_;
1147
1148 ($self->{cbor} ||= cbor_coder)
1149 ->encode ($scalar)
849}; 1150};
850 1151
851=item storable => $reference 1152=item storable => $reference
852 1153
853Freezes the given reference using L<Storable> and writes it to the 1154Freezes the given reference using L<Storable> and writes it to the
856=cut 1157=cut
857 1158
858register_write_type storable => sub { 1159register_write_type storable => sub {
859 my ($self, $ref) = @_; 1160 my ($self, $ref) = @_;
860 1161
861 require Storable; 1162 require Storable unless $Storable::VERSION;
862 1163
863 pack "w/a*", Storable::nfreeze ($ref) 1164 pack "w/a*", Storable::nfreeze ($ref)
864}; 1165};
865 1166
866=back 1167=back
871before it was actually written. One way to do that is to replace your 1172before it was actually written. One way to do that is to replace your
872C<on_drain> handler by a callback that shuts down the socket (and set 1173C<on_drain> handler by a callback that shuts down the socket (and set
873C<low_water_mark> to C<0>). This method is a shorthand for just that, and 1174C<low_water_mark> to C<0>). This method is a shorthand for just that, and
874replaces the C<on_drain> callback with: 1175replaces the C<on_drain> callback with:
875 1176
876 sub { shutdown $_[0]{fh}, 1 } # for push_shutdown 1177 sub { shutdown $_[0]{fh}, 1 }
877 1178
878This simply shuts down the write side and signals an EOF condition to the 1179This simply shuts down the write side and signals an EOF condition to the
879the peer. 1180the peer.
880 1181
881You can rely on the normal read queue and C<on_eof> handling 1182You can rely on the normal read queue and C<on_eof> handling
882afterwards. This is the cleanest way to close a connection. 1183afterwards. This is the cleanest way to close a connection.
883 1184
1185This method may invoke callbacks (and therefore the handle might be
1186destroyed after it returns).
1187
884=cut 1188=cut
885 1189
886sub push_shutdown { 1190sub push_shutdown {
887 my ($self) = @_; 1191 my ($self) = @_;
888 1192
889 delete $self->{low_water_mark}; 1193 delete $self->{low_water_mark};
890 $self->on_drain (sub { shutdown $_[0]{fh}, 1 }); 1194 $self->on_drain (sub { shutdown $_[0]{fh}, 1 });
891} 1195}
892 1196
893=item AnyEvent::Handle::register_write_type type => $coderef->($handle, @args) 1197=item custom write types - Package::anyevent_write_type $handle, @args
894 1198
895This function (not method) lets you add your own types to C<push_write>. 1199Instead of one of the predefined types, you can also specify the name of
1200a package. AnyEvent will try to load the package and then expects to find
1201a function named C<anyevent_write_type> inside. If it isn't found, it
1202progressively tries to load the parent package until it either finds the
1203function (good) or runs out of packages (bad).
1204
896Whenever the given C<type> is used, C<push_write> will invoke the code 1205Whenever the given C<type> is used, C<push_write> will the function with
897reference with the handle object and the remaining arguments. 1206the handle object and the remaining arguments.
898 1207
899The code reference is supposed to return a single octet string that will 1208The function is supposed to return a single octet string that will be
900be appended to the write buffer. 1209appended to the write buffer, so you can mentally treat this function as a
1210"arguments to on-the-wire-format" converter.
901 1211
902Note that this is a function, and all types registered this way will be 1212Example: implement a custom write type C<join> that joins the remaining
903global, so try to use unique names. 1213arguments using the first one.
1214
1215 $handle->push_write (My::Type => " ", 1,2,3);
1216
1217 # uses the following package, which can be defined in the "My::Type" or in
1218 # the "My" modules to be auto-loaded, or just about anywhere when the
1219 # My::Type::anyevent_write_type is defined before invoking it.
1220
1221 package My::Type;
1222
1223 sub anyevent_write_type {
1224 my ($handle, $delim, @args) = @_;
1225
1226 join $delim, @args
1227 }
904 1228
905=cut 1229=cut
906 1230
907############################################################################# 1231#############################################################################
908 1232
917ways, the "simple" way, using only C<on_read> and the "complex" way, using 1241ways, the "simple" way, using only C<on_read> and the "complex" way, using
918a queue. 1242a queue.
919 1243
920In the simple case, you just install an C<on_read> callback and whenever 1244In the simple case, you just install an C<on_read> callback and whenever
921new data arrives, it will be called. You can then remove some data (if 1245new data arrives, it will be called. You can then remove some data (if
922enough is there) from the read buffer (C<< $handle->rbuf >>). Or you cna 1246enough is there) from the read buffer (C<< $handle->rbuf >>). Or you can
923leave the data there if you want to accumulate more (e.g. when only a 1247leave the data there if you want to accumulate more (e.g. when only a
924partial message has been received so far). 1248partial message has been received so far), or change the read queue with
1249e.g. C<push_read>.
925 1250
926In the more complex case, you want to queue multiple callbacks. In this 1251In the more complex case, you want to queue multiple callbacks. In this
927case, AnyEvent::Handle will call the first queued callback each time new 1252case, AnyEvent::Handle will call the first queued callback each time new
928data arrives (also the first time it is queued) and removes it when it has 1253data arrives (also the first time it is queued) and remove it when it has
929done its job (see C<push_read>, below). 1254done its job (see C<push_read>, below).
930 1255
931This way you can, for example, push three line-reads, followed by reading 1256This way you can, for example, push three line-reads, followed by reading
932a chunk of data, and AnyEvent::Handle will execute them in order. 1257a chunk of data, and AnyEvent::Handle will execute them in order.
933 1258
1064 1389
1065This replaces the currently set C<on_read> callback, or clears it (when 1390This replaces the currently set C<on_read> callback, or clears it (when
1066the new callback is C<undef>). See the description of C<on_read> in the 1391the new callback is C<undef>). See the description of C<on_read> in the
1067constructor. 1392constructor.
1068 1393
1394This method may invoke callbacks (and therefore the handle might be
1395destroyed after it returns).
1396
1069=cut 1397=cut
1070 1398
1071sub on_read { 1399sub on_read {
1072 my ($self, $cb) = @_; 1400 my ($self, $cb) = @_;
1073 1401
1075 $self->_drain_rbuf if $cb; 1403 $self->_drain_rbuf if $cb;
1076} 1404}
1077 1405
1078=item $handle->rbuf 1406=item $handle->rbuf
1079 1407
1080Returns the read buffer (as a modifiable lvalue). 1408Returns the read buffer (as a modifiable lvalue). You can also access the
1409read buffer directly as the C<< ->{rbuf} >> member, if you want (this is
1410much faster, and no less clean).
1081 1411
1082You can access the read buffer directly as the C<< ->{rbuf} >> 1412The only operation allowed on the read buffer (apart from looking at it)
1083member, if you want. However, the only operation allowed on the 1413is removing data from its beginning. Otherwise modifying or appending to
1084read buffer (apart from looking at it) is removing data from its 1414it is not allowed and will lead to hard-to-track-down bugs.
1085beginning. Otherwise modifying or appending to it is not allowed and will
1086lead to hard-to-track-down bugs.
1087 1415
1088NOTE: The read buffer should only be used or modified if the C<on_read>, 1416NOTE: The read buffer should only be used or modified in the C<on_read>
1089C<push_read> or C<unshift_read> methods are used. The other read methods 1417callback or when C<push_read> or C<unshift_read> are used with a single
1090automatically manage the read buffer. 1418callback (i.e. untyped). Typed C<push_read> and C<unshift_read> methods
1419will manage the read buffer on their own.
1091 1420
1092=cut 1421=cut
1093 1422
1094sub rbuf : lvalue { 1423sub rbuf : lvalue {
1095 $_[0]{rbuf} 1424 $_[0]{rbuf}
1112 1441
1113If enough data was available, then the callback must remove all data it is 1442If enough data was available, then the callback must remove all data it is
1114interested in (which can be none at all) and return a true value. After returning 1443interested in (which can be none at all) and return a true value. After returning
1115true, it will be removed from the queue. 1444true, it will be removed from the queue.
1116 1445
1446These methods may invoke callbacks (and therefore the handle might be
1447destroyed after it returns).
1448
1117=cut 1449=cut
1118 1450
1119our %RH; 1451our %RH;
1120 1452
1121sub register_read_type($$) { 1453sub register_read_type($$) {
1127 my $cb = pop; 1459 my $cb = pop;
1128 1460
1129 if (@_) { 1461 if (@_) {
1130 my $type = shift; 1462 my $type = shift;
1131 1463
1464 $cb = ($RH{$type} ||= _load_func "$type\::anyevent_read_type"
1132 $cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_read") 1465 or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::push_read")
1133 ->($self, $cb, @_); 1466 ->($self, $cb, @_);
1134 } 1467 }
1135 1468
1136 push @{ $self->{_queue} }, $cb; 1469 push @{ $self->{_queue} }, $cb;
1137 $self->_drain_rbuf; 1470 $self->_drain_rbuf;
1142 my $cb = pop; 1475 my $cb = pop;
1143 1476
1144 if (@_) { 1477 if (@_) {
1145 my $type = shift; 1478 my $type = shift;
1146 1479
1480 $cb = ($RH{$type} ||= _load_func "$type\::anyevent_read_type"
1147 $cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::unshift_read") 1481 or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::unshift_read")
1148 ->($self, $cb, @_); 1482 ->($self, $cb, @_);
1149 } 1483 }
1150
1151 1484
1152 unshift @{ $self->{_queue} }, $cb; 1485 unshift @{ $self->{_queue} }, $cb;
1153 $self->_drain_rbuf; 1486 $self->_drain_rbuf;
1154} 1487}
1155 1488
1157 1490
1158=item $handle->unshift_read (type => @args, $cb) 1491=item $handle->unshift_read (type => @args, $cb)
1159 1492
1160Instead of providing a callback that parses the data itself you can chose 1493Instead of providing a callback that parses the data itself you can chose
1161between a number of predefined parsing formats, for chunks of data, lines 1494between a number of predefined parsing formats, for chunks of data, lines
1162etc. 1495etc. You can also specify the (fully qualified) name of a package, in
1496which case AnyEvent tries to load the package and then expects to find the
1497C<anyevent_read_type> function inside (see "custom read types", below).
1163 1498
1164Predefined types are (if you have ideas for additional types, feel free to 1499Predefined types are (if you have ideas for additional types, feel free to
1165drop by and tell us): 1500drop by and tell us):
1166 1501
1167=over 4 1502=over 4
1173data. 1508data.
1174 1509
1175Example: read 2 bytes. 1510Example: read 2 bytes.
1176 1511
1177 $handle->push_read (chunk => 2, sub { 1512 $handle->push_read (chunk => 2, sub {
1178 warn "yay ", unpack "H*", $_[1]; 1513 say "yay " . unpack "H*", $_[1];
1179 }); 1514 });
1180 1515
1181=cut 1516=cut
1182 1517
1183register_read_type chunk => sub { 1518register_read_type chunk => sub {
1213 1548
1214register_read_type line => sub { 1549register_read_type line => sub {
1215 my ($self, $cb, $eol) = @_; 1550 my ($self, $cb, $eol) = @_;
1216 1551
1217 if (@_ < 3) { 1552 if (@_ < 3) {
1218 # this is more than twice as fast as the generic code below 1553 # this is faster then the generic code below
1219 sub { 1554 sub {
1220 $_[0]{rbuf} =~ s/^([^\015\012]*)(\015?\012)// or return; 1555 (my $pos = index $_[0]{rbuf}, "\012") >= 0
1556 or return;
1221 1557
1558 (my $str = substr $_[0]{rbuf}, 0, $pos + 1, "") =~ s/(\015?\012)\Z// or die;
1222 $cb->($_[0], $1, $2); 1559 $cb->($_[0], $str, "$1");
1223 1 1560 1
1224 } 1561 }
1225 } else { 1562 } else {
1226 $eol = quotemeta $eol unless ref $eol; 1563 $eol = quotemeta $eol unless ref $eol;
1227 $eol = qr|^(.*?)($eol)|s; 1564 $eol = qr|^(.*?)($eol)|s;
1228 1565
1229 sub { 1566 sub {
1230 $_[0]{rbuf} =~ s/$eol// or return; 1567 $_[0]{rbuf} =~ s/$eol// or return;
1231 1568
1232 $cb->($_[0], $1, $2); 1569 $cb->($_[0], "$1", "$2");
1233 1 1570 1
1234 } 1571 }
1235 } 1572 }
1236}; 1573};
1237 1574
1259the receive buffer when neither C<$accept> nor C<$reject> match, 1596the receive buffer when neither C<$accept> nor C<$reject> match,
1260and everything preceding and including the match will be accepted 1597and everything preceding and including the match will be accepted
1261unconditionally. This is useful to skip large amounts of data that you 1598unconditionally. This is useful to skip large amounts of data that you
1262know cannot be matched, so that the C<$accept> or C<$reject> regex do not 1599know cannot be matched, so that the C<$accept> or C<$reject> regex do not
1263have to start matching from the beginning. This is purely an optimisation 1600have to start matching from the beginning. This is purely an optimisation
1264and is usually worth only when you expect more than a few kilobytes. 1601and is usually worth it only when you expect more than a few kilobytes.
1265 1602
1266Example: expect a http header, which ends at C<\015\012\015\012>. Since we 1603Example: expect a http header, which ends at C<\015\012\015\012>. Since we
1267expect the header to be very large (it isn't in practise, but...), we use 1604expect the header to be very large (it isn't in practice, but...), we use
1268a skip regex to skip initial portions. The skip regex is tricky in that 1605a skip regex to skip initial portions. The skip regex is tricky in that
1269it only accepts something not ending in either \015 or \012, as these are 1606it only accepts something not ending in either \015 or \012, as these are
1270required for the accept regex. 1607required for the accept regex.
1271 1608
1272 $handle->push_read (regex => 1609 $handle->push_read (regex =>
1285 1622
1286 sub { 1623 sub {
1287 # accept 1624 # accept
1288 if ($$rbuf =~ $accept) { 1625 if ($$rbuf =~ $accept) {
1289 $data .= substr $$rbuf, 0, $+[0], ""; 1626 $data .= substr $$rbuf, 0, $+[0], "";
1290 $cb->($self, $data); 1627 $cb->($_[0], $data);
1291 return 1; 1628 return 1;
1292 } 1629 }
1293 1630
1294 # reject 1631 # reject
1295 if ($reject && $$rbuf =~ $reject) { 1632 if ($reject && $$rbuf =~ $reject) {
1296 $self->_error (Errno::EBADMSG); 1633 $_[0]->_error (Errno::EBADMSG);
1297 } 1634 }
1298 1635
1299 # skip 1636 # skip
1300 if ($skip && $$rbuf =~ $skip) { 1637 if ($skip && $$rbuf =~ $skip) {
1301 $data .= substr $$rbuf, 0, $+[0], ""; 1638 $data .= substr $$rbuf, 0, $+[0], "";
1317 my ($self, $cb) = @_; 1654 my ($self, $cb) = @_;
1318 1655
1319 sub { 1656 sub {
1320 unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) { 1657 unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
1321 if ($_[0]{rbuf} =~ /[^0-9]/) { 1658 if ($_[0]{rbuf} =~ /[^0-9]/) {
1322 $self->_error (Errno::EBADMSG); 1659 $_[0]->_error (Errno::EBADMSG);
1323 } 1660 }
1324 return; 1661 return;
1325 } 1662 }
1326 1663
1327 my $len = $1; 1664 my $len = $1;
1328 1665
1329 $self->unshift_read (chunk => $len, sub { 1666 $_[0]->unshift_read (chunk => $len, sub {
1330 my $string = $_[1]; 1667 my $string = $_[1];
1331 $_[0]->unshift_read (chunk => 1, sub { 1668 $_[0]->unshift_read (chunk => 1, sub {
1332 if ($_[1] eq ",") { 1669 if ($_[1] eq ",") {
1333 $cb->($_[0], $string); 1670 $cb->($_[0], $string);
1334 } else { 1671 } else {
1335 $self->_error (Errno::EBADMSG); 1672 $_[0]->_error (Errno::EBADMSG);
1336 } 1673 }
1337 }); 1674 });
1338 }); 1675 });
1339 1676
1340 1 1677 1
1390=item json => $cb->($handle, $hash_or_arrayref) 1727=item json => $cb->($handle, $hash_or_arrayref)
1391 1728
1392Reads a JSON object or array, decodes it and passes it to the 1729Reads a JSON object or array, decodes it and passes it to the
1393callback. When a parse error occurs, an C<EBADMSG> error will be raised. 1730callback. When a parse error occurs, an C<EBADMSG> error will be raised.
1394 1731
1395If a C<json> object was passed to the constructor, then that will be used 1732If a C<json> object was passed to the constructor, then that will be
1396for the final decode, otherwise it will create a JSON coder expecting UTF-8. 1733used for the final decode, otherwise it will create a L<JSON::XS> or
1734L<JSON::PP> coder object expecting UTF-8.
1397 1735
1398This read type uses the incremental parser available with JSON version 1736This read type uses the incremental parser available with JSON version
13992.09 (and JSON::XS version 2.2) and above. You have to provide a 17372.09 (and JSON::XS version 2.2) and above.
1400dependency on your own: this module will load the JSON module, but
1401AnyEvent does not depend on it itself.
1402 1738
1403Since JSON texts are fully self-delimiting, the C<json> read and write 1739Since JSON texts are fully self-delimiting, the C<json> read and write
1404types are an ideal simple RPC protocol: just exchange JSON datagrams. See 1740types are an ideal simple RPC protocol: just exchange JSON datagrams. See
1405the C<json> write type description, above, for an actual example. 1741the C<json> write type description, above, for an actual example.
1406 1742
1407=cut 1743=cut
1408 1744
1409register_read_type json => sub { 1745register_read_type json => sub {
1410 my ($self, $cb) = @_; 1746 my ($self, $cb) = @_;
1411 1747
1412 my $json = $self->{json} ||= 1748 my $json = $self->{json} ||= json_coder;
1413 eval { require JSON::XS; JSON::XS->new->utf8 }
1414 || do { require JSON; JSON->new->utf8 };
1415 1749
1416 my $data; 1750 my $data;
1417 my $rbuf = \$self->{rbuf};
1418 1751
1419 sub { 1752 sub {
1420 my $ref = eval { $json->incr_parse ($self->{rbuf}) }; 1753 my $ref = eval { $json->incr_parse ($_[0]{rbuf}) };
1421 1754
1422 if ($ref) { 1755 if ($ref) {
1423 $self->{rbuf} = $json->incr_text; 1756 $_[0]{rbuf} = $json->incr_text;
1424 $json->incr_text = ""; 1757 $json->incr_text = "";
1425 $cb->($self, $ref); 1758 $cb->($_[0], $ref);
1426 1759
1427 1 1760 1
1428 } elsif ($@) { 1761 } elsif ($@) {
1429 # error case 1762 # error case
1430 $json->incr_skip; 1763 $json->incr_skip;
1431 1764
1432 $self->{rbuf} = $json->incr_text; 1765 $_[0]{rbuf} = $json->incr_text;
1433 $json->incr_text = ""; 1766 $json->incr_text = "";
1434 1767
1435 $self->_error (Errno::EBADMSG); 1768 $_[0]->_error (Errno::EBADMSG);
1436 1769
1437 () 1770 ()
1438 } else { 1771 } else {
1439 $self->{rbuf} = ""; 1772 $_[0]{rbuf} = "";
1440 1773
1774 ()
1775 }
1776 }
1777};
1778
1779=item cbor => $cb->($handle, $scalar)
1780
1781Reads a CBOR value, decodes it and passes it to the callback. When a parse
1782error occurs, an C<EBADMSG> error will be raised.
1783
1784If a L<CBOR::XS> object was passed to the constructor, then that will be
1785used for the final decode, otherwise it will create a CBOR coder without
1786enabling any options.
1787
1788You have to provide a dependency to L<CBOR::XS> on your own: this module
1789will load the L<CBOR::XS> module, but AnyEvent does not depend on it
1790itself.
1791
1792Since CBOR values are fully self-delimiting, the C<cbor> read and write
1793types are an ideal simple RPC protocol: just exchange CBOR datagrams. See
1794the C<cbor> write type description, above, for an actual example.
1795
1796=cut
1797
1798register_read_type cbor => sub {
1799 my ($self, $cb) = @_;
1800
1801 my $cbor = $self->{cbor} ||= cbor_coder;
1802
1803 my $data;
1804
1805 sub {
1806 my (@value) = eval { $cbor->incr_parse ($_[0]{rbuf}) };
1807
1808 if (@value) {
1809 $cb->($_[0], @value);
1810
1811 1
1812 } elsif ($@) {
1813 # error case
1814 $cbor->incr_reset;
1815
1816 $_[0]->_error (Errno::EBADMSG);
1817
1818 ()
1819 } else {
1441 () 1820 ()
1442 } 1821 }
1443 } 1822 }
1444}; 1823};
1445 1824
1454=cut 1833=cut
1455 1834
1456register_read_type storable => sub { 1835register_read_type storable => sub {
1457 my ($self, $cb) = @_; 1836 my ($self, $cb) = @_;
1458 1837
1459 require Storable; 1838 require Storable unless $Storable::VERSION;
1460 1839
1461 sub { 1840 sub {
1462 # when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method 1841 # when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
1463 defined (my $len = eval { unpack "w", $_[0]{rbuf} }) 1842 defined (my $len = eval { unpack "w", $_[0]{rbuf} })
1464 or return; 1843 or return;
1467 1846
1468 # bypass unshift if we already have the remaining chunk 1847 # bypass unshift if we already have the remaining chunk
1469 if ($format + $len <= length $_[0]{rbuf}) { 1848 if ($format + $len <= length $_[0]{rbuf}) {
1470 my $data = substr $_[0]{rbuf}, $format, $len; 1849 my $data = substr $_[0]{rbuf}, $format, $len;
1471 substr $_[0]{rbuf}, 0, $format + $len, ""; 1850 substr $_[0]{rbuf}, 0, $format + $len, "";
1851
1472 $cb->($_[0], Storable::thaw ($data)); 1852 eval { $cb->($_[0], Storable::thaw ($data)); 1 }
1853 or return $_[0]->_error (Errno::EBADMSG);
1473 } else { 1854 } else {
1474 # remove prefix 1855 # remove prefix
1475 substr $_[0]{rbuf}, 0, $format, ""; 1856 substr $_[0]{rbuf}, 0, $format, "";
1476 1857
1477 # read remaining chunk 1858 # read remaining chunk
1478 $_[0]->unshift_read (chunk => $len, sub { 1859 $_[0]->unshift_read (chunk => $len, sub {
1479 if (my $ref = eval { Storable::thaw ($_[1]) }) { 1860 eval { $cb->($_[0], Storable::thaw ($_[1])); 1 }
1480 $cb->($_[0], $ref);
1481 } else {
1482 $self->_error (Errno::EBADMSG); 1861 or $_[0]->_error (Errno::EBADMSG);
1483 }
1484 }); 1862 });
1485 } 1863 }
1486 1864
1487 1 1865 1
1488 } 1866 }
1489}; 1867};
1490 1868
1869=item tls_detect => $cb->($handle, $detect, $major, $minor)
1870
1871Checks the input stream for a valid SSL or TLS handshake TLSPaintext
1872record without consuming anything. Only SSL version 3 or higher
1873is handled, up to the fictituous protocol 4.x (but both SSL3+ and
1874SSL2-compatible framing is supported).
1875
1876If it detects that the input data is likely TLS, it calls the callback
1877with a true value for C<$detect> and the (on-wire) TLS version as second
1878and third argument (C<$major> is C<3>, and C<$minor> is 0..3 for SSL
18793.0, TLS 1.0, 1.1 and 1.2, respectively). If it detects the input to
1880be definitely not TLS, it calls the callback with a false value for
1881C<$detect>.
1882
1883The callback could use this information to decide whether or not to start
1884TLS negotiation.
1885
1886In all cases the data read so far is passed to the following read
1887handlers.
1888
1889Usually you want to use the C<tls_autostart> read type instead.
1890
1891If you want to design a protocol that works in the presence of TLS
1892dtection, make sure that any non-TLS data doesn't start with the octet 22
1893(ASCII SYN, 16 hex) or 128-255 (i.e. highest bit set). The checks this
1894read type does are a bit more strict, but might losen in the future to
1895accomodate protocol changes.
1896
1897This read type does not rely on L<AnyEvent::TLS> (and thus, not on
1898L<Net::SSLeay>).
1899
1900=item tls_autostart => $tls[, $tls_ctx]
1901
1902Tries to detect a valid SSL or TLS handshake. If one is detected, it tries
1903to start tls by calling C<starttls> with the given arguments.
1904
1905In practise, C<$tls> must be C<accept>, or a Net::SSLeay context that has
1906been configured to accept, as servers do not normally send a handshake on
1907their own and ths cannot be detected in this way.
1908
1909See C<tls_detect> above for more details.
1910
1911Example: give the client a chance to start TLS before accepting a text
1912line.
1913
1914 $hdl->push_read (tls_detect => "accept");
1915 $hdl->push_read (line => sub {
1916 print "received ", ($_[0]{tls} ? "encrypted" : "cleartext"), " <$_[1]>\n";
1917 });
1918
1919=cut
1920
1921register_read_type tls_detect => sub {
1922 my ($self, $cb) = @_;
1923
1924 sub {
1925 # this regex matches a full or partial tls record
1926 if (
1927 # ssl3+: type(22=handshake) major(=3) minor(any) length_hi
1928 $self->{rbuf} =~ /^(?:\z| \x16 (\z| [\x03\x04] (?:\z| . (?:\z| [\x00-\x40] ))))/xs
1929 # ssl2 comapatible: len_hi len_lo type(1) major minor dummy(forlength)
1930 or $self->{rbuf} =~ /^(?:\z| [\x80-\xff] (?:\z| . (?:\z| \x01 (\z| [\x03\x04] (?:\z| . (?:\z| . ))))))/xs
1931 ) {
1932 return if 3 != length $1; # partial match, can't decide yet
1933
1934 # full match, valid TLS record
1935 my ($major, $minor) = unpack "CC", $1;
1936 $cb->($self, "accept", $major + $minor * 0.1);
1937 } else {
1938 # mismatch == guaranteed not TLS
1939 $cb->($self, undef);
1940 }
1941
1942 1
1943 }
1944};
1945
1946register_read_type tls_autostart => sub {
1947 my ($self, @tls) = @_;
1948
1949 $RH{tls_detect}($self, sub {
1950 return unless $_[1];
1951 $_[0]->starttls (@tls);
1952 })
1953};
1954
1491=back 1955=back
1492 1956
1493=item AnyEvent::Handle::register_read_type type => $coderef->($handle, $cb, @args) 1957=item custom read types - Package::anyevent_read_type $handle, $cb, @args
1494 1958
1495This function (not method) lets you add your own types to C<push_read>. 1959Instead of one of the predefined types, you can also specify the name
1960of a package. AnyEvent will try to load the package and then expects to
1961find a function named C<anyevent_read_type> inside. If it isn't found, it
1962progressively tries to load the parent package until it either finds the
1963function (good) or runs out of packages (bad).
1496 1964
1497Whenever the given C<type> is used, C<push_read> will invoke the code 1965Whenever this type is used, C<push_read> will invoke the function with the
1498reference with the handle object, the callback and the remaining 1966handle object, the original callback and the remaining arguments.
1499arguments.
1500 1967
1501The code reference is supposed to return a callback (usually a closure) 1968The function is supposed to return a callback (usually a closure) that
1502that works as a plain read callback (see C<< ->push_read ($cb) >>). 1969works as a plain read callback (see C<< ->push_read ($cb) >>), so you can
1970mentally treat the function as a "configurable read type to read callback"
1971converter.
1503 1972
1504It should invoke the passed callback when it is done reading (remember to 1973It should invoke the original callback when it is done reading (remember
1505pass C<$handle> as first argument as all other callbacks do that). 1974to pass C<$handle> as first argument as all other callbacks do that,
1975although there is no strict requirement on this).
1506 1976
1507Note that this is a function, and all types registered this way will be
1508global, so try to use unique names.
1509
1510For examples, see the source of this module (F<perldoc -m AnyEvent::Handle>, 1977For examples, see the source of this module (F<perldoc -m
1511search for C<register_read_type>)). 1978AnyEvent::Handle>, search for C<register_read_type>)).
1512 1979
1513=item $handle->stop_read 1980=item $handle->stop_read
1514 1981
1515=item $handle->start_read 1982=item $handle->start_read
1516 1983
1522Note that AnyEvent::Handle will automatically C<start_read> for you when 1989Note that AnyEvent::Handle will automatically C<start_read> for you when
1523you change the C<on_read> callback or push/unshift a read callback, and it 1990you change the C<on_read> callback or push/unshift a read callback, and it
1524will automatically C<stop_read> for you when neither C<on_read> is set nor 1991will automatically C<stop_read> for you when neither C<on_read> is set nor
1525there are any read requests in the queue. 1992there are any read requests in the queue.
1526 1993
1527These methods will have no effect when in TLS mode (as TLS doesn't support 1994In older versions of this module (<= 5.3), these methods had no effect,
1528half-duplex connections). 1995as TLS does not support half-duplex connections. In current versions they
1996work as expected, as this behaviour is required to avoid certain resource
1997attacks, where the program would be forced to read (and buffer) arbitrary
1998amounts of data before being able to send some data. The drawback is that
1999some readings of the the SSL/TLS specifications basically require this
2000attack to be working, as SSL/TLS implementations might stall sending data
2001during a rehandshake.
2002
2003As a guideline, during the initial handshake, you should not stop reading,
2004and as a client, it might cause problems, depending on your application.
1529 2005
1530=cut 2006=cut
1531 2007
1532sub stop_read { 2008sub stop_read {
1533 my ($self) = @_; 2009 my ($self) = @_;
1534 2010
1535 delete $self->{_rw} unless $self->{tls}; 2011 delete $self->{_rw};
1536} 2012}
1537 2013
1538sub start_read { 2014sub start_read {
1539 my ($self) = @_; 2015 my ($self) = @_;
1540 2016
1541 unless ($self->{_rw} || $self->{_eof}) { 2017 unless ($self->{_rw} || $self->{_eof} || !$self->{fh}) {
1542 Scalar::Util::weaken $self; 2018 Scalar::Util::weaken $self;
1543 2019
1544 $self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub { 2020 $self->{_rw} = AE::io $self->{fh}, 0, sub {
1545 my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf}); 2021 my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf});
1546 my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf; 2022 my $len = sysread $self->{fh}, $$rbuf, $self->{read_size}, length $$rbuf;
1547 2023
1548 if ($len > 0) { 2024 if ($len > 0) {
1549 $self->{_activity} = AnyEvent->now; 2025 $self->{_activity} = $self->{_ractivity} = AE::now;
1550 2026
1551 if ($self->{tls}) { 2027 if ($self->{tls}) {
1552 Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf); 2028 Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf);
1553 2029
1554 &_dotls ($self); 2030 &_dotls ($self);
1555 } else { 2031 } else {
1556 $self->_drain_rbuf; 2032 $self->_drain_rbuf;
1557 } 2033 }
1558 2034
2035 if ($len == $self->{read_size}) {
2036 $self->{read_size} *= 2;
2037 $self->{read_size} = $self->{max_read_size} || MAX_READ_SIZE
2038 if $self->{read_size} > ($self->{max_read_size} || MAX_READ_SIZE);
2039 }
2040
1559 } elsif (defined $len) { 2041 } elsif (defined $len) {
1560 delete $self->{_rw}; 2042 delete $self->{_rw};
1561 $self->{_eof} = 1; 2043 $self->{_eof} = 1;
1562 $self->_drain_rbuf; 2044 $self->_drain_rbuf;
1563 2045
1564 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) { 2046 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
1565 return $self->_error ($!, 1); 2047 return $self->_error ($!, 1);
1566 } 2048 }
1567 }); 2049 };
1568 } 2050 }
1569} 2051}
1570 2052
1571our $ERROR_SYSCALL; 2053our $ERROR_SYSCALL;
1572our $ERROR_WANT_READ; 2054our $ERROR_WANT_READ;
1575 my ($self, $err) = @_; 2057 my ($self, $err) = @_;
1576 2058
1577 return $self->_error ($!, 1) 2059 return $self->_error ($!, 1)
1578 if $err == Net::SSLeay::ERROR_SYSCALL (); 2060 if $err == Net::SSLeay::ERROR_SYSCALL ();
1579 2061
1580 my $err =Net::SSLeay::ERR_error_string (Net::SSLeay::ERR_get_error ()); 2062 my $err = Net::SSLeay::ERR_error_string (Net::SSLeay::ERR_get_error ());
1581 2063
1582 # reduce error string to look less scary 2064 # reduce error string to look less scary
1583 $err =~ s/^error:[0-9a-fA-F]{8}:[^:]+:([^:]+):/\L$1: /; 2065 $err =~ s/^error:[0-9a-fA-F]{8}:[^:]+:([^:]+):/\L$1: /;
1584 2066
1585 if ($self->{_on_starttls}) { 2067 if ($self->{_on_starttls}) {
1599sub _dotls { 2081sub _dotls {
1600 my ($self) = @_; 2082 my ($self) = @_;
1601 2083
1602 my $tmp; 2084 my $tmp;
1603 2085
1604 if (length $self->{_tls_wbuf}) { 2086 while (length $self->{_tls_wbuf}) {
1605 while (($tmp = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) { 2087 if (($tmp = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) <= 0) {
1606 substr $self->{_tls_wbuf}, 0, $tmp, ""; 2088 $tmp = Net::SSLeay::get_error ($self->{tls}, $tmp);
2089
2090 return $self->_tls_error ($tmp)
2091 if $tmp != $ERROR_WANT_READ
2092 && ($tmp != $ERROR_SYSCALL || $!);
2093
2094 last;
1607 } 2095 }
1608 2096
1609 $tmp = Net::SSLeay::get_error ($self->{tls}, $tmp); 2097 substr $self->{_tls_wbuf}, 0, $tmp, "";
1610 return $self->_tls_error ($tmp)
1611 if $tmp != $ERROR_WANT_READ
1612 && ($tmp != $ERROR_SYSCALL || $!);
1613 } 2098 }
1614 2099
1615 while (defined ($tmp = Net::SSLeay::read ($self->{tls}))) { 2100 while (defined ($tmp = Net::SSLeay::read ($self->{tls}))) {
1616 unless (length $tmp) { 2101 unless (length $tmp) {
1617 $self->{_on_starttls} 2102 $self->{_on_starttls}
1631 $self->{_tls_rbuf} .= $tmp; 2116 $self->{_tls_rbuf} .= $tmp;
1632 $self->_drain_rbuf; 2117 $self->_drain_rbuf;
1633 $self->{tls} or return; # tls session might have gone away in callback 2118 $self->{tls} or return; # tls session might have gone away in callback
1634 } 2119 }
1635 2120
1636 $tmp = Net::SSLeay::get_error ($self->{tls}, -1); 2121 $tmp = Net::SSLeay::get_error ($self->{tls}, -1); # -1 is not neccessarily correct, but Net::SSLeay doesn't tell us
1637 return $self->_tls_error ($tmp) 2122 return $self->_tls_error ($tmp)
1638 if $tmp != $ERROR_WANT_READ 2123 if $tmp != $ERROR_WANT_READ
1639 && ($tmp != $ERROR_SYSCALL || $!); 2124 && ($tmp != $ERROR_SYSCALL || $!);
1640 2125
1641 while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) { 2126 while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) {
1642 $self->{wbuf} .= $tmp; 2127 $self->{wbuf} .= $tmp;
1643 $self->_drain_wbuf; 2128 $self->_drain_wbuf;
2129 $self->{tls} or return; # tls session might have gone away in callback
1644 } 2130 }
1645 2131
1646 $self->{_on_starttls} 2132 $self->{_on_starttls}
1647 and Net::SSLeay::state ($self->{tls}) == Net::SSLeay::ST_OK () 2133 and Net::SSLeay::state ($self->{tls}) == Net::SSLeay::ST_OK ()
1648 and (delete $self->{_on_starttls})->($self, 1, "TLS/SSL connection established"); 2134 and (delete $self->{_on_starttls})->($self, 1, "TLS/SSL connection established");
1650 2136
1651=item $handle->starttls ($tls[, $tls_ctx]) 2137=item $handle->starttls ($tls[, $tls_ctx])
1652 2138
1653Instead of starting TLS negotiation immediately when the AnyEvent::Handle 2139Instead of starting TLS negotiation immediately when the AnyEvent::Handle
1654object is created, you can also do that at a later time by calling 2140object is created, you can also do that at a later time by calling
1655C<starttls>. 2141C<starttls>. See the C<tls> constructor argument for general info.
1656 2142
1657Starting TLS is currently an asynchronous operation - when you push some 2143Starting TLS is currently an asynchronous operation - when you push some
1658write data and then call C<< ->starttls >> then TLS negotiation will start 2144write data and then call C<< ->starttls >> then TLS negotiation will start
1659immediately, after which the queued write data is then sent. 2145immediately, after which the queued write data is then sent. This might
2146change in future versions, so best make sure you have no outstanding write
2147data when calling this method.
1660 2148
1661The first argument is the same as the C<tls> constructor argument (either 2149The first argument is the same as the C<tls> constructor argument (either
1662C<"connect">, C<"accept"> or an existing Net::SSLeay object). 2150C<"connect">, C<"accept"> or an existing Net::SSLeay object).
1663 2151
1664The second argument is the optional C<AnyEvent::TLS> object that is used 2152The second argument is the optional C<AnyEvent::TLS> object that is used
1670context in C<< $handle->{tls_ctx} >> after this call and can be used or 2158context in C<< $handle->{tls_ctx} >> after this call and can be used or
1671changed to your liking. Note that the handshake might have already started 2159changed to your liking. Note that the handshake might have already started
1672when this function returns. 2160when this function returns.
1673 2161
1674Due to bugs in OpenSSL, it might or might not be possible to do multiple 2162Due to bugs in OpenSSL, it might or might not be possible to do multiple
1675handshakes on the same stream. Best do not attempt to use the stream after 2163handshakes on the same stream. It is best to not attempt to use the
1676stopping TLS. 2164stream after stopping TLS.
2165
2166This method may invoke callbacks (and therefore the handle might be
2167destroyed after it returns).
1677 2168
1678=cut 2169=cut
1679 2170
1680our %TLS_CACHE; #TODO not yet documented, should we? 2171our %TLS_CACHE; #TODO not yet documented, should we?
1681 2172
1683 my ($self, $tls, $ctx) = @_; 2174 my ($self, $tls, $ctx) = @_;
1684 2175
1685 Carp::croak "It is an error to call starttls on an AnyEvent::Handle object while TLS is already active, caught" 2176 Carp::croak "It is an error to call starttls on an AnyEvent::Handle object while TLS is already active, caught"
1686 if $self->{tls}; 2177 if $self->{tls};
1687 2178
2179 unless (defined $AnyEvent::TLS::VERSION) {
2180 eval {
2181 require Net::SSLeay;
2182 require AnyEvent::TLS;
2183 1
2184 } or return $self->_error (Errno::EPROTO, 1, "TLS support not available on this system");
2185 }
2186
1688 $self->{tls} = $tls; 2187 $self->{tls} = $tls;
1689 $self->{tls_ctx} = $ctx if @_ > 2; 2188 $self->{tls_ctx} = $ctx if @_ > 2;
1690 2189
1691 return unless $self->{fh}; 2190 return unless $self->{fh};
1692 2191
1693 require Net::SSLeay;
1694
1695 $ERROR_SYSCALL = Net::SSLeay::ERROR_SYSCALL (); 2192 $ERROR_SYSCALL = Net::SSLeay::ERROR_SYSCALL ();
1696 $ERROR_WANT_READ = Net::SSLeay::ERROR_WANT_READ (); 2193 $ERROR_WANT_READ = Net::SSLeay::ERROR_WANT_READ ();
1697 2194
1698 $tls = $self->{tls}; 2195 $tls = delete $self->{tls};
1699 $ctx = $self->{tls_ctx}; 2196 $ctx = $self->{tls_ctx};
1700 2197
1701 local $Carp::CarpLevel = 1; # skip ourselves when creating a new context or session 2198 local $Carp::CarpLevel = 1; # skip ourselves when creating a new context or session
1702 2199
1703 if ("HASH" eq ref $ctx) { 2200 if ("HASH" eq ref $ctx) {
1704 require AnyEvent::TLS;
1705
1706 if ($ctx->{cache}) { 2201 if ($ctx->{cache}) {
1707 my $key = $ctx+0; 2202 my $key = $ctx+0;
1708 $ctx = $TLS_CACHE{$key} ||= new AnyEvent::TLS %$ctx; 2203 $ctx = $TLS_CACHE{$key} ||= new AnyEvent::TLS %$ctx;
1709 } else { 2204 } else {
1710 $ctx = new AnyEvent::TLS %$ctx; 2205 $ctx = new AnyEvent::TLS %$ctx;
1732 Net::SSLeay::CTX_set_mode ($tls, 1|2); 2227 Net::SSLeay::CTX_set_mode ($tls, 1|2);
1733 2228
1734 $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); 2229 $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1735 $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); 2230 $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1736 2231
2232 Net::SSLeay::BIO_write ($self->{_rbio}, $self->{rbuf});
2233 $self->{rbuf} = "";
2234
1737 Net::SSLeay::set_bio ($tls, $self->{_rbio}, $self->{_wbio}); 2235 Net::SSLeay::set_bio ($tls, $self->{_rbio}, $self->{_wbio});
1738 2236
1739 $self->{_on_starttls} = sub { $_[0]{on_starttls}(@_) } 2237 $self->{_on_starttls} = sub { $_[0]{on_starttls}(@_) }
1740 if $self->{on_starttls}; 2238 if $self->{on_starttls};
1741 2239
1745 2243
1746=item $handle->stoptls 2244=item $handle->stoptls
1747 2245
1748Shuts down the SSL connection - this makes a proper EOF handshake by 2246Shuts down the SSL connection - this makes a proper EOF handshake by
1749sending a close notify to the other side, but since OpenSSL doesn't 2247sending a close notify to the other side, but since OpenSSL doesn't
1750support non-blocking shut downs, it is not guarenteed that you can re-use 2248support non-blocking shut downs, it is not guaranteed that you can re-use
1751the stream afterwards. 2249the stream afterwards.
2250
2251This method may invoke callbacks (and therefore the handle might be
2252destroyed after it returns).
1752 2253
1753=cut 2254=cut
1754 2255
1755sub stoptls { 2256sub stoptls {
1756 my ($self) = @_; 2257 my ($self) = @_;
1757 2258
1758 if ($self->{tls}) { 2259 if ($self->{tls} && $self->{fh}) {
1759 Net::SSLeay::shutdown ($self->{tls}); 2260 Net::SSLeay::shutdown ($self->{tls});
1760 2261
1761 &_dotls; 2262 &_dotls;
1762 2263
1763# # we don't give a shit. no, we do, but we can't. no...#d# 2264# # we don't give a shit. no, we do, but we can't. no...#d#
1770 my ($self) = @_; 2271 my ($self) = @_;
1771 2272
1772 return unless $self->{tls}; 2273 return unless $self->{tls};
1773 2274
1774 $self->{tls_ctx}->_put_session (delete $self->{tls}) 2275 $self->{tls_ctx}->_put_session (delete $self->{tls})
1775 if ref $self->{tls}; 2276 if $self->{tls} > 0;
1776 2277
1777 delete @$self{qw(_rbio _wbio _tls_wbuf _on_starttls)}; 2278 delete @$self{qw(_rbio _wbio _tls_wbuf _on_starttls)};
1778} 2279}
2280
2281=item $handle->resettls
2282
2283This rarely-used method simply resets and TLS state on the handle, usually
2284causing data loss.
2285
2286One case where it may be useful is when you want to skip over the data in
2287the stream but you are not interested in interpreting it, so data loss is
2288no concern.
2289
2290=cut
2291
2292*resettls = \&_freetls;
1779 2293
1780sub DESTROY { 2294sub DESTROY {
1781 my ($self) = @_; 2295 my ($self) = @_;
1782 2296
1783 &_freetls; 2297 &_freetls;
1788 my $fh = delete $self->{fh}; 2302 my $fh = delete $self->{fh};
1789 my $wbuf = delete $self->{wbuf}; 2303 my $wbuf = delete $self->{wbuf};
1790 2304
1791 my @linger; 2305 my @linger;
1792 2306
1793 push @linger, AnyEvent->io (fh => $fh, poll => "w", cb => sub { 2307 push @linger, AE::io $fh, 1, sub {
1794 my $len = syswrite $fh, $wbuf, length $wbuf; 2308 my $len = syswrite $fh, $wbuf, length $wbuf;
1795 2309
1796 if ($len > 0) { 2310 if ($len > 0) {
1797 substr $wbuf, 0, $len, ""; 2311 substr $wbuf, 0, $len, "";
1798 } else { 2312 } elsif (defined $len || ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK)) {
1799 @linger = (); # end 2313 @linger = (); # end
1800 } 2314 }
1801 }); 2315 };
1802 push @linger, AnyEvent->timer (after => $linger, cb => sub { 2316 push @linger, AE::timer $linger, 0, sub {
1803 @linger = (); 2317 @linger = ();
1804 }); 2318 };
1805 } 2319 }
1806} 2320}
1807 2321
1808=item $handle->destroy 2322=item $handle->destroy
1809 2323
1840 2354
1841sub AnyEvent::Handle::destroyed::AUTOLOAD { 2355sub AnyEvent::Handle::destroyed::AUTOLOAD {
1842 #nop 2356 #nop
1843} 2357}
1844 2358
2359=item $handle->destroyed
2360
2361Returns false as long as the handle hasn't been destroyed by a call to C<<
2362->destroy >>, true otherwise.
2363
2364Can be useful to decide whether the handle is still valid after some
2365callback possibly destroyed the handle. For example, C<< ->push_write >>,
2366C<< ->starttls >> and other methods can call user callbacks, which in turn
2367can destroy the handle, so work can be avoided by checking sometimes:
2368
2369 $hdl->starttls ("accept");
2370 return if $hdl->destroyed;
2371 $hdl->push_write (...
2372
2373Note that the call to C<push_write> will silently be ignored if the handle
2374has been destroyed, so often you can just ignore the possibility of the
2375handle being destroyed.
2376
2377=cut
2378
2379sub destroyed { 0 }
2380sub AnyEvent::Handle::destroyed::destroyed { 1 }
2381
1845=item AnyEvent::Handle::TLS_CTX 2382=item AnyEvent::Handle::TLS_CTX
1846 2383
1847This function creates and returns the AnyEvent::TLS object used by default 2384This function creates and returns the AnyEvent::TLS object used by default
1848for TLS mode. 2385for TLS mode.
1849 2386
1876 2413
1877It is only safe to "forget" the reference inside EOF or error callbacks, 2414It is only safe to "forget" the reference inside EOF or error callbacks,
1878from within all other callbacks, you need to explicitly call the C<< 2415from within all other callbacks, you need to explicitly call the C<<
1879->destroy >> method. 2416->destroy >> method.
1880 2417
2418=item Why is my C<on_eof> callback never called?
2419
2420Probably because your C<on_error> callback is being called instead: When
2421you have outstanding requests in your read queue, then an EOF is
2422considered an error as you clearly expected some data.
2423
2424To avoid this, make sure you have an empty read queue whenever your handle
2425is supposed to be "idle" (i.e. connection closes are O.K.). You can set
2426an C<on_read> handler that simply pushes the first read requests in the
2427queue.
2428
2429See also the next question, which explains this in a bit more detail.
2430
2431=item How can I serve requests in a loop?
2432
2433Most protocols consist of some setup phase (authentication for example)
2434followed by a request handling phase, where the server waits for requests
2435and handles them, in a loop.
2436
2437There are two important variants: The first (traditional, better) variant
2438handles requests until the server gets some QUIT command, causing it to
2439close the connection first (highly desirable for a busy TCP server). A
2440client dropping the connection is an error, which means this variant can
2441detect an unexpected detection close.
2442
2443To handle this case, always make sure you have a non-empty read queue, by
2444pushing the "read request start" handler on it:
2445
2446 # we assume a request starts with a single line
2447 my @start_request; @start_request = (line => sub {
2448 my ($hdl, $line) = @_;
2449
2450 ... handle request
2451
2452 # push next request read, possibly from a nested callback
2453 $hdl->push_read (@start_request);
2454 });
2455
2456 # auth done, now go into request handling loop
2457 # now push the first @start_request
2458 $hdl->push_read (@start_request);
2459
2460By always having an outstanding C<push_read>, the handle always expects
2461some data and raises the C<EPIPE> error when the connction is dropped
2462unexpectedly.
2463
2464The second variant is a protocol where the client can drop the connection
2465at any time. For TCP, this means that the server machine may run out of
2466sockets easier, and in general, it means you cannot distinguish a protocl
2467failure/client crash from a normal connection close. Nevertheless, these
2468kinds of protocols are common (and sometimes even the best solution to the
2469problem).
2470
2471Having an outstanding read request at all times is possible if you ignore
2472C<EPIPE> errors, but this doesn't help with when the client drops the
2473connection during a request, which would still be an error.
2474
2475A better solution is to push the initial request read in an C<on_read>
2476callback. This avoids an error, as when the server doesn't expect data
2477(i.e. is idly waiting for the next request, an EOF will not raise an
2478error, but simply result in an C<on_eof> callback. It is also a bit slower
2479and simpler:
2480
2481 # auth done, now go into request handling loop
2482 $hdl->on_read (sub {
2483 my ($hdl) = @_;
2484
2485 # called each time we receive data but the read queue is empty
2486 # simply start read the request
2487
2488 $hdl->push_read (line => sub {
2489 my ($hdl, $line) = @_;
2490
2491 ... handle request
2492
2493 # do nothing special when the request has been handled, just
2494 # let the request queue go empty.
2495 });
2496 });
2497
1881=item I get different callback invocations in TLS mode/Why can't I pause 2498=item I get different callback invocations in TLS mode/Why can't I pause
1882reading? 2499reading?
1883 2500
1884Unlike, say, TCP, TLS connections do not consist of two independent 2501Unlike, say, TCP, TLS connections do not consist of two independent
1885communication channels, one for each direction. Or put differently. The 2502communication channels, one for each direction. Or put differently, the
1886read and write directions are not independent of each other: you cannot 2503read and write directions are not independent of each other: you cannot
1887write data unless you are also prepared to read, and vice versa. 2504write data unless you are also prepared to read, and vice versa.
1888 2505
1889This can mean than, in TLS mode, you might get C<on_error> or C<on_eof> 2506This means that, in TLS mode, you might get C<on_error> or C<on_eof>
1890callback invocations when you are not expecting any read data - the reason 2507callback invocations when you are not expecting any read data - the reason
1891is that AnyEvent::Handle always reads in TLS mode. 2508is that AnyEvent::Handle always reads in TLS mode.
1892 2509
1893During the connection, you have to make sure that you always have a 2510During the connection, you have to make sure that you always have a
1894non-empty read-queue, or an C<on_read> watcher. At the end of the 2511non-empty read-queue, or an C<on_read> watcher. At the end of the
1906 $handle->on_eof (undef); 2523 $handle->on_eof (undef);
1907 $handle->on_error (sub { 2524 $handle->on_error (sub {
1908 my $data = delete $_[0]{rbuf}; 2525 my $data = delete $_[0]{rbuf};
1909 }); 2526 });
1910 2527
2528Note that this example removes the C<rbuf> member from the handle object,
2529which is not normally allowed by the API. It is expressly permitted in
2530this case only, as the handle object needs to be destroyed afterwards.
2531
1911The reason to use C<on_error> is that TCP connections, due to latencies 2532The reason to use C<on_error> is that TCP connections, due to latencies
1912and packets loss, might get closed quite violently with an error, when in 2533and packets loss, might get closed quite violently with an error, when in
1913fact, all data has been received. 2534fact all data has been received.
1914 2535
1915It is usually better to use acknowledgements when transferring data, 2536It is usually better to use acknowledgements when transferring data,
1916to make sure the other side hasn't just died and you got the data 2537to make sure the other side hasn't just died and you got the data
1917intact. This is also one reason why so many internet protocols have an 2538intact. This is also one reason why so many internet protocols have an
1918explicit QUIT command. 2539explicit QUIT command.
1925C<low_water_mark> this will be called precisely when all data has been 2546C<low_water_mark> this will be called precisely when all data has been
1926written to the socket: 2547written to the socket:
1927 2548
1928 $handle->push_write (...); 2549 $handle->push_write (...);
1929 $handle->on_drain (sub { 2550 $handle->on_drain (sub {
1930 warn "all data submitted to the kernel\n"; 2551 AE::log debug => "All data submitted to the kernel.";
1931 undef $handle; 2552 undef $handle;
1932 }); 2553 });
1933 2554
1934If you just want to queue some data and then signal EOF to the other side, 2555If you just want to queue some data and then signal EOF to the other side,
1935consider using C<< ->push_shutdown >> instead. 2556consider using C<< ->push_shutdown >> instead.
1936 2557
1937=item I want to contact a TLS/SSL server, I don't care about security. 2558=item I want to contact a TLS/SSL server, I don't care about security.
1938 2559
1939If your TLS server is a pure TLS server (e.g. HTTPS) that only speaks TLS, 2560If your TLS server is a pure TLS server (e.g. HTTPS) that only speaks TLS,
1940simply connect to it and then create the AnyEvent::Handle with the C<tls> 2561connect to it and then create the AnyEvent::Handle with the C<tls>
1941parameter: 2562parameter:
1942 2563
1943 tcp_connect $host, $port, sub { 2564 tcp_connect $host, $port, sub {
1944 my ($fh) = @_; 2565 my ($fh) = @_;
1945 2566
2019When you have intermediate CA certificates that your clients might not 2640When you have intermediate CA certificates that your clients might not
2020know about, just append them to the C<cert_file>. 2641know about, just append them to the C<cert_file>.
2021 2642
2022=back 2643=back
2023 2644
2024
2025=head1 SUBCLASSING AnyEvent::Handle 2645=head1 SUBCLASSING AnyEvent::Handle
2026 2646
2027In many cases, you might want to subclass AnyEvent::Handle. 2647In many cases, you might want to subclass AnyEvent::Handle.
2028 2648
2029To make this easier, a given version of AnyEvent::Handle uses these 2649To make this easier, a given version of AnyEvent::Handle uses these
2045 2665
2046=item * all members not documented here and not prefixed with an underscore 2666=item * all members not documented here and not prefixed with an underscore
2047are free to use in subclasses. 2667are free to use in subclasses.
2048 2668
2049Of course, new versions of AnyEvent::Handle may introduce more "public" 2669Of course, new versions of AnyEvent::Handle may introduce more "public"
2050member variables, but thats just life, at least it is documented. 2670member variables, but that's just life. At least it is documented.
2051 2671
2052=back 2672=back
2053 2673
2054=head1 AUTHOR 2674=head1 AUTHOR
2055 2675
2056Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>. 2676Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>.
2057 2677
2058=cut 2678=cut
2059 2679
20601; # End of AnyEvent::Handle 26801
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