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Revision 1.232 by root, Fri Mar 30 03:11:17 2012 UTC

1package AnyEvent::Handle;
2
3no warnings;
4use strict qw(subs vars);
5
6use AnyEvent ();
7use AnyEvent::Util qw(WSAEWOULDBLOCK);
8use Scalar::Util ();
9use Carp ();
10use Fcntl ();
11use Errno qw(EAGAIN EINTR);
12
13=head1 NAME 1=head1 NAME
14 2
15AnyEvent::Handle - non-blocking I/O on file handles via AnyEvent 3AnyEvent::Handle - non-blocking I/O on streaming handles via AnyEvent
16
17=cut
18
19our $VERSION = 4.34;
20 4
21=head1 SYNOPSIS 5=head1 SYNOPSIS
22 6
23 use AnyEvent; 7 use AnyEvent;
24 use AnyEvent::Handle; 8 use AnyEvent::Handle;
25 9
26 my $cv = AnyEvent->condvar; 10 my $cv = AnyEvent->condvar;
27 11
28 my $handle = 12 my $hdl; $hdl = new AnyEvent::Handle
29 AnyEvent::Handle->new (
30 fh => \*STDIN, 13 fh => \*STDIN,
31 on_eof => sub { 14 on_error => sub {
15 my ($hdl, $fatal, $msg) = @_;
16 AE::log error => "Got error $msg!";
17 $hdl->destroy;
32 $cv->send; 18 $cv->send;
33 },
34 ); 19 };
35 20
36 # send some request line 21 # send some request line
37 $handle->push_write ("getinfo\015\012"); 22 $hdl->push_write ("getinfo\015\012");
38 23
39 # read the response line 24 # read the response line
40 $handle->push_read (line => sub { 25 $hdl->push_read (line => sub {
41 my ($handle, $line) = @_; 26 my ($hdl, $line) = @_;
42 warn "read line <$line>\n"; 27 say "got line <$line>";
43 $cv->send; 28 $cv->send;
44 }); 29 });
45 30
46 $cv->recv; 31 $cv->recv;
47 32
48=head1 DESCRIPTION 33=head1 DESCRIPTION
49 34
50This 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
51filehandles. For utility functions for doing non-blocking connects and accepts 36stream-based filehandles (sockets, pipes, and other stream things).
52on sockets see L<AnyEvent::Util>.
53 37
54The L<AnyEvent::Intro> tutorial contains some well-documented 38The L<AnyEvent::Intro> tutorial contains some well-documented
55AnyEvent::Handle examples. 39AnyEvent::Handle examples.
56 40
57In the following, when the documentation refers to of "bytes" then this 41In the following, where the documentation refers to "bytes", it means
58means characters. As sysread and syswrite are used for all I/O, their 42characters. As sysread and syswrite are used for all I/O, their
59treatment of characters applies to this module as well. 43treatment of characters applies to this module as well.
44
45At the very minimum, you should specify C<fh> or C<connect>, and the
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 B<new (%args)> 86=item $handle = B<new> AnyEvent::Handle fh => $filehandle, key => value...
69 87
70The constructor supports these arguments (all as key => value pairs). 88The constructor supports these arguments (all as C<< key => value >> pairs).
71 89
72=over 4 90=over 4
73 91
74=item fh => $filehandle [MANDATORY] 92=item fh => $filehandle [C<fh> or C<connect> MANDATORY]
75 93
76The filehandle this L<AnyEvent::Handle> object will operate on. 94The filehandle this L<AnyEvent::Handle> object will operate on.
77
78NOTE: The filehandle will be set to non-blocking mode (using 95NOTE: The filehandle will be set to non-blocking mode (using
79C<AnyEvent::Util::fh_nonblocking>) by the constructor and needs to stay in 96C<AnyEvent::Util::fh_nonblocking>) by the constructor and needs to stay in
80that mode. 97that mode.
81 98
99=item connect => [$host, $service] [C<fh> or C<connect> MANDATORY]
100
101Try to connect to the specified host and service (port), using
102C<AnyEvent::Socket::tcp_connect>. The C<$host> additionally becomes the
103default C<peername>.
104
105You have to specify either this parameter, or C<fh>, above.
106
107It is possible to push requests on the read and write queues, and modify
108properties of the stream, even while AnyEvent::Handle is connecting.
109
110When this parameter is specified, then the C<on_prepare>,
111C<on_connect_error> and C<on_connect> callbacks will be called under the
112appropriate circumstances:
113
114=over 4
115
116=item on_prepare => $cb->($handle)
117
118This (rarely used) callback is called before a new connection is
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
121file handle with parameters required for the actual connect (as opposed to
122settings that can be changed when the connection is already established).
123
124The return value of this callback should be the connect timeout value in
125seconds (or C<0>, or C<undef>, or the empty list, to indicate that the
126default timeout is to be used).
127
128=item on_connect => $cb->($handle, $host, $port, $retry->())
129
130This callback is called when a connection has been successfully established.
131
132The peer's numeric host and port (the socket peername) are passed as
133parameters, together with a retry callback. At the time it is called the
134read and write queues, EOF status, TLS status and similar properties of
135the handle will have been reset.
136
137It is not allowed to use the read or write queues while the handle object
138is connecting.
139
140If, for some reason, the handle is not acceptable, calling C<$retry> will
141continue with the next connection target (in case of multi-homed hosts or
142SRV records there can be multiple connection endpoints). The C<$retry>
143callback can be invoked after the connect callback returns, i.e. one can
144start a handshake and then decide to retry with the next host if the
145handshake fails.
146
147In most cases, you should ignore the C<$retry> parameter.
148
149=item on_connect_error => $cb->($handle, $message)
150
151This callback is called when the connection could not be
152established. C<$!> will contain the relevant error code, and C<$message> a
153message describing it (usually the same as C<"$!">).
154
155If this callback isn't specified, then C<on_error> will be called with a
156fatal error instead.
157
158=back
159
160=item on_error => $cb->($handle, $fatal, $message)
161
162This is the error callback, which is called when, well, some error
163occured, such as not being able to resolve the hostname, failure to
164connect, or a read error.
165
166Some errors are fatal (which is indicated by C<$fatal> being true). On
167fatal errors the handle object will be destroyed (by a call to C<< ->
168destroy >>) after invoking the error callback (which means you are free to
169examine the handle object). Examples of fatal errors are an EOF condition
170with active (but unsatisfiable) read watchers (C<EPIPE>) or I/O errors. In
171cases where the other side can close the connection at will, it is
172often easiest to not report C<EPIPE> errors in this callback.
173
174AnyEvent::Handle tries to find an appropriate error code for you to check
175against, but in some cases (TLS errors), this does not work well. It is
176recommended to always output the C<$message> argument in human-readable
177error messages (it's usually the same as C<"$!">).
178
179Non-fatal errors can be retried by returning, but it is recommended
180to simply ignore this parameter and instead abondon the handle object
181when this callback is invoked. Examples of non-fatal errors are timeouts
182C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>).
183
184On entry to the callback, the value of C<$!> contains the operating
185system error code (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT>, C<EBADMSG> or
186C<EPROTO>).
187
188While not mandatory, it is I<highly> recommended to set this callback, as
189you will not be notified of errors otherwise. The default just calls
190C<croak>.
191
192=item on_read => $cb->($handle)
193
194This sets the default read callback, which is called when data arrives
195and no read request is in the queue (unlike read queue callbacks, this
196callback will only be called when at least one octet of data is in the
197read buffer).
198
199To access (and remove data from) the read buffer, use the C<< ->rbuf >>
200method or access the C<< $handle->{rbuf} >> member directly. Note that you
201must not enlarge or modify the read buffer, you can only remove data at
202the beginning from it.
203
204You can also call C<< ->push_read (...) >> or any other function that
205modifies the read queue. Or do both. Or ...
206
207When an EOF condition is detected, AnyEvent::Handle will first try to
208feed all the remaining data to the queued callbacks and C<on_read> before
209calling the C<on_eof> callback. If no progress can be made, then a fatal
210error will be raised (with C<$!> set to C<EPIPE>).
211
212Note that, unlike requests in the read queue, an C<on_read> callback
213doesn't mean you I<require> some data: if there is an EOF and there
214are outstanding read requests then an error will be flagged. With an
215C<on_read> callback, the C<on_eof> callback will be invoked.
216
82=item on_eof => $cb->($handle) 217=item on_eof => $cb->($handle)
83 218
84Set the callback to be called when an end-of-file condition is detected, 219Set the callback to be called when an end-of-file condition is detected,
85i.e. in the case of a socket, when the other side has closed the 220i.e. in the case of a socket, when the other side has closed the
86connection cleanly. 221connection cleanly, and there are no outstanding read requests in the
222queue (if there are read requests, then an EOF counts as an unexpected
223connection close and will be flagged as an error).
87 224
88For sockets, this just means that the other side has stopped sending data, 225For sockets, this just means that the other side has stopped sending data,
89you can still try to write data, and, in fact, one can return from the EOF 226you can still try to write data, and, in fact, one can return from the EOF
90callback and continue writing data, as only the read part has been shut 227callback and continue writing data, as only the read part has been shut
91down. 228down.
92 229
93While not mandatory, it is I<highly> recommended to set an EOF callback,
94otherwise you might end up with a closed socket while you are still
95waiting for data.
96
97If an EOF condition has been detected but no C<on_eof> callback has been 230If an EOF condition has been detected but no C<on_eof> callback has been
98set, then a fatal error will be raised with C<$!> set to <0>. 231set, then a fatal error will be raised with C<$!> set to <0>.
99 232
100=item on_error => $cb->($handle, $fatal)
101
102This is the error callback, which is called when, well, some error
103occured, such as not being able to resolve the hostname, failure to
104connect or a read error.
105
106Some errors are fatal (which is indicated by C<$fatal> being true). On
107fatal errors the handle object will be shut down and will not be usable
108(but you are free to look at the current C<< ->rbuf >>). Examples of fatal
109errors are an EOF condition with active (but unsatisifable) read watchers
110(C<EPIPE>) or I/O errors.
111
112Non-fatal errors can be retried by simply returning, but it is recommended
113to simply ignore this parameter and instead abondon the handle object
114when this callback is invoked. Examples of non-fatal errors are timeouts
115C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>).
116
117On callback entrance, the value of C<$!> contains the operating system
118error (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT> or C<EBADMSG>).
119
120While not mandatory, it is I<highly> recommended to set this callback, as
121you will not be notified of errors otherwise. The default simply calls
122C<croak>.
123
124=item on_read => $cb->($handle)
125
126This sets the default read callback, which is called when data arrives
127and no read request is in the queue (unlike read queue callbacks, this
128callback will only be called when at least one octet of data is in the
129read buffer).
130
131To access (and remove data from) the read buffer, use the C<< ->rbuf >>
132method or access the C<$handle->{rbuf}> member directly. Note that you
133must not enlarge or modify the read buffer, you can only remove data at
134the beginning from it.
135
136When an EOF condition is detected then AnyEvent::Handle will first try to
137feed all the remaining data to the queued callbacks and C<on_read> before
138calling the C<on_eof> callback. If no progress can be made, then a fatal
139error will be raised (with C<$!> set to C<EPIPE>).
140
141=item on_drain => $cb->($handle) 233=item on_drain => $cb->($handle)
142 234
143This sets the callback that is called when the write buffer becomes empty 235This sets the callback that is called once when the write buffer becomes
144(or when the callback is set and the buffer is empty already). 236empty (and immediately when the handle object is created).
145 237
146To append to the write buffer, use the C<< ->push_write >> method. 238To append to the write buffer, use the C<< ->push_write >> method.
147 239
148This callback is useful when you don't want to put all of your write data 240This callback is useful when you don't want to put all of your write data
149into the queue at once, for example, when you want to write the contents 241into the queue at once, for example, when you want to write the contents
151memory and push it into the queue, but instead only read more data from 243memory and push it into the queue, but instead only read more data from
152the file when the write queue becomes empty. 244the file when the write queue becomes empty.
153 245
154=item timeout => $fractional_seconds 246=item timeout => $fractional_seconds
155 247
248=item rtimeout => $fractional_seconds
249
250=item wtimeout => $fractional_seconds
251
156If non-zero, then this enables an "inactivity" timeout: whenever this many 252If non-zero, then these enables an "inactivity" timeout: whenever this
157seconds pass without a successful read or write on the underlying file 253many seconds pass without a successful read or write on the underlying
158handle, the C<on_timeout> callback will be invoked (and if that one is 254file handle (or a call to C<timeout_reset>), the C<on_timeout> callback
159missing, a non-fatal C<ETIMEDOUT> error will be raised). 255will be invoked (and if that one is missing, a non-fatal C<ETIMEDOUT>
256error will be raised).
160 257
258There are three variants of the timeouts that work independently of each
259other, for both read and write (triggered when nothing was read I<OR>
260written), just read (triggered when nothing was read), and just write:
261C<timeout>, C<rtimeout> and C<wtimeout>, with corresponding callbacks
262C<on_timeout>, C<on_rtimeout> and C<on_wtimeout>, and reset functions
263C<timeout_reset>, C<rtimeout_reset>, and C<wtimeout_reset>.
264
161Note that timeout processing is also active when you currently do not have 265Note that timeout processing is active even when you do not have any
162any outstanding read or write requests: If you plan to keep the connection 266outstanding read or write requests: If you plan to keep the connection
163idle then you should disable the timout temporarily or ignore the timeout 267idle then you should disable the timeout temporarily or ignore the
164in the C<on_timeout> callback, in which case AnyEvent::Handle will simply 268timeout in the corresponding C<on_timeout> callback, in which case
165restart the timeout. 269AnyEvent::Handle will simply restart the timeout.
166 270
167Zero (the default) disables this timeout. 271Zero (the default) disables the corresponding timeout.
168 272
169=item on_timeout => $cb->($handle) 273=item on_timeout => $cb->($handle)
274
275=item on_rtimeout => $cb->($handle)
276
277=item on_wtimeout => $cb->($handle)
170 278
171Called whenever the inactivity timeout passes. If you return from this 279Called whenever the inactivity timeout passes. If you return from this
172callback, then the timeout will be reset as if some activity had happened, 280callback, then the timeout will be reset as if some activity had happened,
173so this condition is not fatal in any way. 281so this condition is not fatal in any way.
174 282
182be configured to accept only so-and-so much data that it cannot act on 290be configured to accept only so-and-so much data that it cannot act on
183(for example, when expecting a line, an attacker could send an unlimited 291(for example, when expecting a line, an attacker could send an unlimited
184amount of data without a callback ever being called as long as the line 292amount of data without a callback ever being called as long as the line
185isn't finished). 293isn't finished).
186 294
295=item wbuf_max => <bytes>
296
297If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)
298when the write buffer ever (strictly) exceeds this size. This is useful to
299avoid some forms of denial-of-service attacks.
300
301Although the units of this parameter is bytes, this is the I<raw> number
302of bytes not yet accepted by the kernel. This can make a difference when
303you e.g. use TLS, as TLS typically makes your write data larger (but it
304can also make it smaller due to compression).
305
306As an example of when this limit is useful, take a chat server that sends
307chat messages to a client. If the client does not read those in a timely
308manner then the send buffer in the server would grow unbounded.
309
187=item autocork => <boolean> 310=item autocork => <boolean>
188 311
189When disabled (the default), then C<push_write> will try to immediately 312When disabled (the default), C<push_write> will try to immediately
190write the data to the handle, if possible. This avoids having to register 313write the data to the handle if possible. This avoids having to register
191a write watcher and wait for the next event loop iteration, but can 314a write watcher and wait for the next event loop iteration, but can
192be inefficient if you write multiple small chunks (on the wire, this 315be inefficient if you write multiple small chunks (on the wire, this
193disadvantage is usually avoided by your kernel's nagle algorithm, see 316disadvantage is usually avoided by your kernel's nagle algorithm, see
194C<no_delay>, but this option can save costly syscalls). 317C<no_delay>, but this option can save costly syscalls).
195 318
196When enabled, then writes will always be queued till the next event loop 319When enabled, writes will always be queued till the next event loop
197iteration. This is efficient when you do many small writes per iteration, 320iteration. This is efficient when you do many small writes per iteration,
198but less efficient when you do a single write only per iteration (or when 321but less efficient when you do a single write only per iteration (or when
199the write buffer often is full). It also increases write latency. 322the write buffer often is full). It also increases write latency.
200 323
201=item no_delay => <boolean> 324=item no_delay => <boolean>
205the Nagle algorithm, and usually it is beneficial. 328the Nagle algorithm, and usually it is beneficial.
206 329
207In some situations you want as low a delay as possible, which can be 330In some situations you want as low a delay as possible, which can be
208accomplishd by setting this option to a true value. 331accomplishd by setting this option to a true value.
209 332
210The default is your opertaing system's default behaviour (most likely 333The default is your operating system's default behaviour (most likely
211enabled), this option explicitly enables or disables it, if possible. 334enabled). This option explicitly enables or disables it, if possible.
335
336=item keepalive => <boolean>
337
338Enables (default disable) the SO_KEEPALIVE option on the stream socket:
339normally, TCP connections have no time-out once established, so TCP
340connections, once established, can stay alive forever even when the other
341side has long gone. TCP keepalives are a cheap way to take down long-lived
342TCP connections when the other side becomes unreachable. While the default
343is OS-dependent, TCP keepalives usually kick in after around two hours,
344and, if the other side doesn't reply, take down the TCP connection some 10
345to 15 minutes later.
346
347It is harmless to specify this option for file handles that do not support
348keepalives, and enabling it on connections that are potentially long-lived
349is usually a good idea.
350
351=item oobinline => <boolean>
352
353BSD majorly fucked up the implementation of TCP urgent data. The result
354is that almost no OS implements TCP according to the specs, and every OS
355implements it slightly differently.
356
357If you want to handle TCP urgent data, then setting this flag (the default
358is enabled) gives you the most portable way of getting urgent data, by
359putting it into the stream.
360
361Since BSD emulation of OOB data on top of TCP's urgent data can have
362security implications, AnyEvent::Handle sets this flag automatically
363unless explicitly specified. Note that setting this flag after
364establishing a connection I<may> be a bit too late (data loss could
365already have occured on BSD systems), but at least it will protect you
366from most attacks.
212 367
213=item read_size => <bytes> 368=item read_size => <bytes>
214 369
215The default read block size (the amount of bytes this module will 370The initial read block size, the number of bytes this module will try
216try to read during each loop iteration, which affects memory 371to read during each loop iteration. Each handle object will consume
217requirements). Default: C<8192>. 372at least this amount of memory for the read buffer as well, so when
373handling many connections watch out for memory requirements). See also
374C<max_read_size>. Default: C<2048>.
375
376=item max_read_size => <bytes>
377
378The maximum read buffer size used by the dynamic adjustment
379algorithm: Each time AnyEvent::Handle can read C<read_size> bytes in
380one go it will double C<read_size> up to the maximum given by this
381option. Default: C<131072> or C<read_size>, whichever is higher.
218 382
219=item low_water_mark => <bytes> 383=item low_water_mark => <bytes>
220 384
221Sets the amount of bytes (default: C<0>) that make up an "empty" write 385Sets the number of bytes (default: C<0>) that make up an "empty" write
222buffer: If the write reaches this size or gets even samller it is 386buffer: If the buffer reaches this size or gets even samller it is
223considered empty. 387considered empty.
224 388
225Sometimes it can be beneficial (for performance reasons) to add data to 389Sometimes it can be beneficial (for performance reasons) to add data to
226the write buffer before it is fully drained, but this is a rare case, as 390the write buffer before it is fully drained, but this is a rare case, as
227the operating system kernel usually buffers data as well, so the default 391the operating system kernel usually buffers data as well, so the default
228is good in almost all cases. 392is good in almost all cases.
229 393
230=item linger => <seconds> 394=item linger => <seconds>
231 395
232If non-zero (default: C<3600>), then the destructor of the 396If this is non-zero (default: C<3600>), the destructor of the
233AnyEvent::Handle object will check whether there is still outstanding 397AnyEvent::Handle object will check whether there is still outstanding
234write data and will install a watcher that will write this data to the 398write data and will install a watcher that will write this data to the
235socket. No errors will be reported (this mostly matches how the operating 399socket. No errors will be reported (this mostly matches how the operating
236system treats outstanding data at socket close time). 400system treats outstanding data at socket close time).
237 401
238This will not work for partial TLS data that could not be encoded 402This will not work for partial TLS data that could not be encoded
239yet. This data will be lost. Calling the C<stoptls> method in time might 403yet. This data will be lost. Calling the C<stoptls> method in time might
240help. 404help.
241 405
406=item peername => $string
407
408A string used to identify the remote site - usually the DNS hostname
409(I<not> IDN!) used to create the connection, rarely the IP address.
410
411Apart from being useful in error messages, this string is also used in TLS
412peername verification (see C<verify_peername> in L<AnyEvent::TLS>). This
413verification will be skipped when C<peername> is not specified or is
414C<undef>.
415
242=item tls => "accept" | "connect" | Net::SSLeay::SSL object 416=item tls => "accept" | "connect" | Net::SSLeay::SSL object
243 417
244When this parameter is given, it enables TLS (SSL) mode, that means 418When this parameter is given, it enables TLS (SSL) mode, that means
245AnyEvent will start a TLS handshake as soon as the conenction has been 419AnyEvent will start a TLS handshake as soon as the connection has been
246established and will transparently encrypt/decrypt data afterwards. 420established and will transparently encrypt/decrypt data afterwards.
421
422All TLS protocol errors will be signalled as C<EPROTO>, with an
423appropriate error message.
247 424
248TLS mode requires Net::SSLeay to be installed (it will be loaded 425TLS mode requires Net::SSLeay to be installed (it will be loaded
249automatically when you try to create a TLS handle): this module doesn't 426automatically when you try to create a TLS handle): this module doesn't
250have a dependency on that module, so if your module requires it, you have 427have a dependency on that module, so if your module requires it, you have
251to add the dependency yourself. 428to add the dependency yourself.
255mode. 432mode.
256 433
257You can also provide your own TLS connection object, but you have 434You can also provide your own TLS connection object, but you have
258to make sure that you call either C<Net::SSLeay::set_connect_state> 435to make sure that you call either C<Net::SSLeay::set_connect_state>
259or C<Net::SSLeay::set_accept_state> on it before you pass it to 436or C<Net::SSLeay::set_accept_state> on it before you pass it to
260AnyEvent::Handle. 437AnyEvent::Handle. Also, this module will take ownership of this connection
438object.
439
440At some future point, AnyEvent::Handle might switch to another TLS
441implementation, then the option to use your own session object will go
442away.
261 443
262B<IMPORTANT:> since Net::SSLeay "objects" are really only integers, 444B<IMPORTANT:> since Net::SSLeay "objects" are really only integers,
263passing in the wrong integer will lead to certain crash. This most often 445passing in the wrong integer will lead to certain crash. This most often
264happens when one uses a stylish C<< tls => 1 >> and is surprised about the 446happens when one uses a stylish C<< tls => 1 >> and is surprised about the
265segmentation fault. 447segmentation fault.
266 448
267See the C<< ->starttls >> method for when need to start TLS negotiation later. 449Use the C<< ->starttls >> method if you need to start TLS negotiation later.
268 450
269=item tls_ctx => $ssl_ctx 451=item tls_ctx => $anyevent_tls
270 452
271Use the given C<Net::SSLeay::CTX> object to create the new TLS connection 453Use the given C<AnyEvent::TLS> object to create the new TLS connection
272(unless a connection object was specified directly). If this parameter is 454(unless a connection object was specified directly). If this
273missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>. 455parameter is missing (or C<undef>), then AnyEvent::Handle will use
456C<AnyEvent::Handle::TLS_CTX>.
457
458Instead of an object, you can also specify a hash reference with C<< key
459=> value >> pairs. Those will be passed to L<AnyEvent::TLS> to create a
460new TLS context object.
461
462=item on_starttls => $cb->($handle, $success[, $error_message])
463
464This callback will be invoked when the TLS/SSL handshake has finished. If
465C<$success> is true, then the TLS handshake succeeded, otherwise it failed
466(C<on_stoptls> will not be called in this case).
467
468The session in C<< $handle->{tls} >> can still be examined in this
469callback, even when the handshake was not successful.
470
471TLS handshake failures will not cause C<on_error> to be invoked when this
472callback is in effect, instead, the error message will be passed to C<on_starttls>.
473
474Without this callback, handshake failures lead to C<on_error> being
475called as usual.
476
477Note that you cannot just call C<starttls> again in this callback. If you
478need to do that, start an zero-second timer instead whose callback can
479then call C<< ->starttls >> again.
480
481=item on_stoptls => $cb->($handle)
482
483When a SSLv3/TLS shutdown/close notify/EOF is detected and this callback is
484set, then it will be invoked after freeing the TLS session. If it is not,
485then a TLS shutdown condition will be treated like a normal EOF condition
486on the handle.
487
488The session in C<< $handle->{tls} >> can still be examined in this
489callback.
490
491This callback will only be called on TLS shutdowns, not when the
492underlying handle signals EOF.
274 493
275=item json => JSON or JSON::XS object 494=item json => JSON or JSON::XS object
276 495
277This is the json coder object used by the C<json> read and write types. 496This is the json coder object used by the C<json> read and write types.
278 497
287 506
288=cut 507=cut
289 508
290sub new { 509sub new {
291 my $class = shift; 510 my $class = shift;
292
293 my $self = bless { @_ }, $class; 511 my $self = bless { @_ }, $class;
294 512
295 $self->{fh} or Carp::croak "mandatory argument fh is missing"; 513 if ($self->{fh}) {
514 $self->_start;
515 return unless $self->{fh}; # could be gone by now
516
517 } elsif ($self->{connect}) {
518 require AnyEvent::Socket;
519
520 $self->{peername} = $self->{connect}[0]
521 unless exists $self->{peername};
522
523 $self->{_skip_drain_rbuf} = 1;
524
525 {
526 Scalar::Util::weaken (my $self = $self);
527
528 $self->{_connect} =
529 AnyEvent::Socket::tcp_connect (
530 $self->{connect}[0],
531 $self->{connect}[1],
532 sub {
533 my ($fh, $host, $port, $retry) = @_;
534
535 delete $self->{_connect}; # no longer needed
536
537 if ($fh) {
538 $self->{fh} = $fh;
539
540 delete $self->{_skip_drain_rbuf};
541 $self->_start;
542
543 $self->{on_connect}
544 and $self->{on_connect}($self, $host, $port, sub {
545 delete @$self{qw(fh _tw _rtw _wtw _ww _rw _eof _queue rbuf _wbuf tls _tls_rbuf _tls_wbuf)};
546 $self->{_skip_drain_rbuf} = 1;
547 &$retry;
548 });
549
550 } else {
551 if ($self->{on_connect_error}) {
552 $self->{on_connect_error}($self, "$!");
553 $self->destroy if $self;
554 } else {
555 $self->_error ($!, 1);
556 }
557 }
558 },
559 sub {
560 local $self->{fh} = $_[0];
561
562 $self->{on_prepare}
563 ? $self->{on_prepare}->($self)
564 : ()
565 }
566 );
567 }
568
569 } else {
570 Carp::croak "AnyEvent::Handle: either an existing fh or the connect parameter must be specified";
571 }
572
573 $self
574}
575
576sub _start {
577 my ($self) = @_;
578
579 # too many clueless people try to use udp and similar sockets
580 # with AnyEvent::Handle, do them a favour.
581 my $type = getsockopt $self->{fh}, Socket::SOL_SOCKET (), Socket::SO_TYPE ();
582 Carp::croak "AnyEvent::Handle: only stream sockets supported, anything else will NOT work!"
583 if Socket::SOCK_STREAM () != (unpack "I", $type) && defined $type;
296 584
297 AnyEvent::Util::fh_nonblocking $self->{fh}, 1; 585 AnyEvent::Util::fh_nonblocking $self->{fh}, 1;
298 586
587 $self->{_activity} =
588 $self->{_ractivity} =
589 $self->{_wactivity} = AE::now;
590
591 $self->{read_size} ||= 2048;
592 $self->{max_read_size} = $self->{read_size}
593 if $self->{read_size} > ($self->{max_read_size} || MAX_READ_SIZE);
594
595 $self->timeout (delete $self->{timeout} ) if $self->{timeout};
596 $self->rtimeout (delete $self->{rtimeout} ) if $self->{rtimeout};
597 $self->wtimeout (delete $self->{wtimeout} ) if $self->{wtimeout};
598
599 $self->no_delay (delete $self->{no_delay} ) if exists $self->{no_delay} && $self->{no_delay};
600 $self->keepalive (delete $self->{keepalive}) if exists $self->{keepalive} && $self->{keepalive};
601
602 $self->oobinline (exists $self->{oobinline} ? delete $self->{oobinline} : 1);
603
299 $self->starttls (delete $self->{tls}, delete $self->{tls_ctx}) 604 $self->starttls (delete $self->{tls}, delete $self->{tls_ctx})
300 if $self->{tls}; 605 if $self->{tls};
301 606
302 $self->{_activity} = AnyEvent->now;
303 $self->_timeout;
304
305 $self->on_drain (delete $self->{on_drain}) if exists $self->{on_drain}; 607 $self->on_drain (delete $self->{on_drain} ) if $self->{on_drain};
306 $self->no_delay (delete $self->{no_delay}) if exists $self->{no_delay};
307 608
308 $self->start_read 609 $self->start_read
309 if $self->{on_read}; 610 if $self->{on_read} || @{ $self->{_queue} };
310 611
311 $self 612 $self->_drain_wbuf;
312}
313
314sub _shutdown {
315 my ($self) = @_;
316
317 delete $self->{_tw};
318 delete $self->{_rw};
319 delete $self->{_ww};
320 delete $self->{fh};
321
322 &_freetls;
323
324 delete $self->{on_read};
325 delete $self->{_queue};
326} 613}
327 614
328sub _error { 615sub _error {
329 my ($self, $errno, $fatal) = @_; 616 my ($self, $errno, $fatal, $message) = @_;
330
331 $self->_shutdown
332 if $fatal;
333 617
334 $! = $errno; 618 $! = $errno;
619 $message ||= "$!";
335 620
336 if ($self->{on_error}) { 621 if ($self->{on_error}) {
337 $self->{on_error}($self, $fatal); 622 $self->{on_error}($self, $fatal, $message);
338 } elsif ($self->{fh}) { 623 $self->destroy if $fatal;
624 } elsif ($self->{fh} || $self->{connect}) {
625 $self->destroy;
339 Carp::croak "AnyEvent::Handle uncaught error: $!"; 626 Carp::croak "AnyEvent::Handle uncaught error: $message";
340 } 627 }
341} 628}
342 629
343=item $fh = $handle->fh 630=item $fh = $handle->fh
344 631
368 $_[0]{on_eof} = $_[1]; 655 $_[0]{on_eof} = $_[1];
369} 656}
370 657
371=item $handle->on_timeout ($cb) 658=item $handle->on_timeout ($cb)
372 659
373Replace the current C<on_timeout> callback, or disables the callback (but 660=item $handle->on_rtimeout ($cb)
374not the timeout) if C<$cb> = C<undef>. See the C<timeout> constructor
375argument and method.
376 661
377=cut 662=item $handle->on_wtimeout ($cb)
378 663
379sub on_timeout { 664Replace the current C<on_timeout>, C<on_rtimeout> or C<on_wtimeout>
380 $_[0]{on_timeout} = $_[1]; 665callback, or disables the callback (but not the timeout) if C<$cb> =
381} 666C<undef>. See the C<timeout> constructor argument and method.
667
668=cut
669
670# see below
382 671
383=item $handle->autocork ($boolean) 672=item $handle->autocork ($boolean)
384 673
385Enables or disables the current autocork behaviour (see C<autocork> 674Enables or disables the current autocork behaviour (see C<autocork>
386constructor argument). Changes will only take effect on the next write. 675constructor argument). Changes will only take effect on the next write.
399=cut 688=cut
400 689
401sub no_delay { 690sub no_delay {
402 $_[0]{no_delay} = $_[1]; 691 $_[0]{no_delay} = $_[1];
403 692
693 setsockopt $_[0]{fh}, Socket::IPPROTO_TCP (), Socket::TCP_NODELAY (), int $_[1]
694 if $_[0]{fh};
695}
696
697=item $handle->keepalive ($boolean)
698
699Enables or disables the C<keepalive> setting (see constructor argument of
700the same name for details).
701
702=cut
703
704sub keepalive {
705 $_[0]{keepalive} = $_[1];
706
404 eval { 707 eval {
405 local $SIG{__DIE__}; 708 local $SIG{__DIE__};
406 setsockopt $_[0]{fh}, &Socket::IPPROTO_TCP, &Socket::TCP_NODELAY, int $_[1]; 709 setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_KEEPALIVE (), int $_[1]
710 if $_[0]{fh};
407 }; 711 };
408} 712}
409 713
714=item $handle->oobinline ($boolean)
715
716Enables or disables the C<oobinline> setting (see constructor argument of
717the same name for details).
718
719=cut
720
721sub oobinline {
722 $_[0]{oobinline} = $_[1];
723
724 eval {
725 local $SIG{__DIE__};
726 setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_OOBINLINE (), int $_[1]
727 if $_[0]{fh};
728 };
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
741 eval {
742 local $SIG{__DIE__};
743 setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_KEEPALIVE (), int $_[1]
744 if $_[0]{fh};
745 };
746}
747
748=item $handle->on_starttls ($cb)
749
750Replace the current C<on_starttls> callback (see the C<on_starttls> constructor argument).
751
752=cut
753
754sub on_starttls {
755 $_[0]{on_starttls} = $_[1];
756}
757
758=item $handle->on_stoptls ($cb)
759
760Replace the current C<on_stoptls> callback (see the C<on_stoptls> constructor argument).
761
762=cut
763
764sub on_stoptls {
765 $_[0]{on_stoptls} = $_[1];
766}
767
768=item $handle->rbuf_max ($max_octets)
769
770Configures the C<rbuf_max> setting (C<undef> disables it).
771
772=item $handle->wbuf_max ($max_octets)
773
774Configures the C<wbuf_max> setting (C<undef> disables it).
775
776=cut
777
778sub rbuf_max {
779 $_[0]{rbuf_max} = $_[1];
780}
781
782sub wbuf_max {
783 $_[0]{wbuf_max} = $_[1];
784}
785
410############################################################################# 786#############################################################################
411 787
412=item $handle->timeout ($seconds) 788=item $handle->timeout ($seconds)
413 789
790=item $handle->rtimeout ($seconds)
791
792=item $handle->wtimeout ($seconds)
793
414Configures (or disables) the inactivity timeout. 794Configures (or disables) the inactivity timeout.
415 795
416=cut 796The timeout will be checked instantly, so this method might destroy the
797handle before it returns.
417 798
418sub timeout { 799=item $handle->timeout_reset
800
801=item $handle->rtimeout_reset
802
803=item $handle->wtimeout_reset
804
805Reset the activity timeout, as if data was received or sent.
806
807These methods are cheap to call.
808
809=cut
810
811for my $dir ("", "r", "w") {
812 my $timeout = "${dir}timeout";
813 my $tw = "_${dir}tw";
814 my $on_timeout = "on_${dir}timeout";
815 my $activity = "_${dir}activity";
816 my $cb;
817
818 *$on_timeout = sub {
819 $_[0]{$on_timeout} = $_[1];
820 };
821
822 *$timeout = sub {
419 my ($self, $timeout) = @_; 823 my ($self, $new_value) = @_;
420 824
825 $new_value >= 0
826 or Carp::croak "AnyEvent::Handle->$timeout called with negative timeout ($new_value), caught";
827
421 $self->{timeout} = $timeout; 828 $self->{$timeout} = $new_value;
422 $self->_timeout; 829 delete $self->{$tw}; &$cb;
423} 830 };
424 831
832 *{"${dir}timeout_reset"} = sub {
833 $_[0]{$activity} = AE::now;
834 };
835
836 # main workhorse:
425# reset the timeout watcher, as neccessary 837 # reset the timeout watcher, as neccessary
426# also check for time-outs 838 # also check for time-outs
427sub _timeout { 839 $cb = sub {
428 my ($self) = @_; 840 my ($self) = @_;
429 841
430 if ($self->{timeout}) { 842 if ($self->{$timeout} && $self->{fh}) {
431 my $NOW = AnyEvent->now; 843 my $NOW = AE::now;
432 844
433 # when would the timeout trigger? 845 # when would the timeout trigger?
434 my $after = $self->{_activity} + $self->{timeout} - $NOW; 846 my $after = $self->{$activity} + $self->{$timeout} - $NOW;
435 847
436 # now or in the past already? 848 # now or in the past already?
437 if ($after <= 0) { 849 if ($after <= 0) {
438 $self->{_activity} = $NOW; 850 $self->{$activity} = $NOW;
439 851
440 if ($self->{on_timeout}) { 852 if ($self->{$on_timeout}) {
441 $self->{on_timeout}($self); 853 $self->{$on_timeout}($self);
442 } else { 854 } else {
443 $self->_error (&Errno::ETIMEDOUT); 855 $self->_error (Errno::ETIMEDOUT);
856 }
857
858 # callback could have changed timeout value, optimise
859 return unless $self->{$timeout};
860
861 # calculate new after
862 $after = $self->{$timeout};
444 } 863 }
445 864
446 # callback could have changed timeout value, optimise 865 Scalar::Util::weaken $self;
447 return unless $self->{timeout}; 866 return unless $self; # ->error could have destroyed $self
448 867
449 # calculate new after 868 $self->{$tw} ||= AE::timer $after, 0, sub {
450 $after = $self->{timeout}; 869 delete $self->{$tw};
870 $cb->($self);
871 };
872 } else {
873 delete $self->{$tw};
451 } 874 }
452
453 Scalar::Util::weaken $self;
454 return unless $self; # ->error could have destroyed $self
455
456 $self->{_tw} ||= AnyEvent->timer (after => $after, cb => sub {
457 delete $self->{_tw};
458 $self->_timeout;
459 });
460 } else {
461 delete $self->{_tw};
462 } 875 }
463} 876}
464 877
465############################################################################# 878#############################################################################
466 879
473 886
474The write queue is very simple: you can add data to its end, and 887The write queue is very simple: you can add data to its end, and
475AnyEvent::Handle will automatically try to get rid of it for you. 888AnyEvent::Handle will automatically try to get rid of it for you.
476 889
477When data could be written and the write buffer is shorter then the low 890When data could be written and the write buffer is shorter then the low
478water mark, the C<on_drain> callback will be invoked. 891water mark, the C<on_drain> callback will be invoked once.
479 892
480=over 4 893=over 4
481 894
482=item $handle->on_drain ($cb) 895=item $handle->on_drain ($cb)
483 896
484Sets the C<on_drain> callback or clears it (see the description of 897Sets the C<on_drain> callback or clears it (see the description of
485C<on_drain> in the constructor). 898C<on_drain> in the constructor).
486 899
900This method may invoke callbacks (and therefore the handle might be
901destroyed after it returns).
902
487=cut 903=cut
488 904
489sub on_drain { 905sub on_drain {
490 my ($self, $cb) = @_; 906 my ($self, $cb) = @_;
491 907
495 if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf}); 911 if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf});
496} 912}
497 913
498=item $handle->push_write ($data) 914=item $handle->push_write ($data)
499 915
500Queues the given scalar to be written. You can push as much data as you 916Queues the given scalar to be written. You can push as much data as
501want (only limited by the available memory), as C<AnyEvent::Handle> 917you want (only limited by the available memory and C<wbuf_max>), as
502buffers it independently of the kernel. 918C<AnyEvent::Handle> buffers it independently of the kernel.
919
920This method may invoke callbacks (and therefore the handle might be
921destroyed after it returns).
503 922
504=cut 923=cut
505 924
506sub _drain_wbuf { 925sub _drain_wbuf {
507 my ($self) = @_; 926 my ($self) = @_;
511 Scalar::Util::weaken $self; 930 Scalar::Util::weaken $self;
512 931
513 my $cb = sub { 932 my $cb = sub {
514 my $len = syswrite $self->{fh}, $self->{wbuf}; 933 my $len = syswrite $self->{fh}, $self->{wbuf};
515 934
516 if ($len >= 0) { 935 if (defined $len) {
517 substr $self->{wbuf}, 0, $len, ""; 936 substr $self->{wbuf}, 0, $len, "";
518 937
519 $self->{_activity} = AnyEvent->now; 938 $self->{_activity} = $self->{_wactivity} = AE::now;
520 939
521 $self->{on_drain}($self) 940 $self->{on_drain}($self)
522 if $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf}) 941 if $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf})
523 && $self->{on_drain}; 942 && $self->{on_drain};
524 943
530 949
531 # try to write data immediately 950 # try to write data immediately
532 $cb->() unless $self->{autocork}; 951 $cb->() unless $self->{autocork};
533 952
534 # if still data left in wbuf, we need to poll 953 # if still data left in wbuf, we need to poll
535 $self->{_ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb) 954 $self->{_ww} = AE::io $self->{fh}, 1, $cb
536 if length $self->{wbuf}; 955 if length $self->{wbuf};
956
957 if (
958 defined $self->{wbuf_max}
959 && $self->{wbuf_max} < length $self->{wbuf}
960 ) {
961 $self->_error (Errno::ENOSPC, 1), return;
962 }
537 }; 963 };
538} 964}
539 965
540our %WH; 966our %WH;
541 967
968# deprecated
542sub register_write_type($$) { 969sub register_write_type($$) {
543 $WH{$_[0]} = $_[1]; 970 $WH{$_[0]} = $_[1];
544} 971}
545 972
546sub push_write { 973sub push_write {
547 my $self = shift; 974 my $self = shift;
548 975
549 if (@_ > 1) { 976 if (@_ > 1) {
550 my $type = shift; 977 my $type = shift;
551 978
979 @_ = ($WH{$type} ||= _load_func "$type\::anyevent_write_type"
552 @_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write") 980 or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::push_write")
553 ->($self, @_); 981 ->($self, @_);
554 } 982 }
555 983
984 # we downgrade here to avoid hard-to-track-down bugs,
985 # and diagnose the problem earlier and better.
986
556 if ($self->{tls}) { 987 if ($self->{tls}) {
557 $self->{_tls_wbuf} .= $_[0]; 988 utf8::downgrade $self->{_tls_wbuf} .= $_[0];
558 989 &_dotls ($self) if $self->{fh};
559 &_dotls ($self);
560 } else { 990 } else {
561 $self->{wbuf} .= $_[0]; 991 utf8::downgrade $self->{wbuf} .= $_[0];
562 $self->_drain_wbuf; 992 $self->_drain_wbuf if $self->{fh};
563 } 993 }
564} 994}
565 995
566=item $handle->push_write (type => @args) 996=item $handle->push_write (type => @args)
567 997
568Instead of formatting your data yourself, you can also let this module do 998Instead of formatting your data yourself, you can also let this module
569the job by specifying a type and type-specific arguments. 999do the job by specifying a type and type-specific arguments. You
1000can also specify the (fully qualified) name of a package, in which
1001case AnyEvent tries to load the package and then expects to find the
1002C<anyevent_write_type> function inside (see "custom write types", below).
570 1003
571Predefined types are (if you have ideas for additional types, feel free to 1004Predefined types are (if you have ideas for additional types, feel free to
572drop by and tell us): 1005drop by and tell us):
573 1006
574=over 4 1007=over 4
631Other languages could read single lines terminated by a newline and pass 1064Other languages could read single lines terminated by a newline and pass
632this line into their JSON decoder of choice. 1065this line into their JSON decoder of choice.
633 1066
634=cut 1067=cut
635 1068
1069sub json_coder() {
1070 eval { require JSON::XS; JSON::XS->new->utf8 }
1071 || do { require JSON; JSON->new->utf8 }
1072}
1073
636register_write_type json => sub { 1074register_write_type json => sub {
637 my ($self, $ref) = @_; 1075 my ($self, $ref) = @_;
638 1076
639 require JSON; 1077 my $json = $self->{json} ||= json_coder;
640 1078
641 $self->{json} ? $self->{json}->encode ($ref) 1079 $json->encode ($ref)
642 : JSON::encode_json ($ref)
643}; 1080};
644 1081
645=item storable => $reference 1082=item storable => $reference
646 1083
647Freezes the given reference using L<Storable> and writes it to the 1084Freezes the given reference using L<Storable> and writes it to the
650=cut 1087=cut
651 1088
652register_write_type storable => sub { 1089register_write_type storable => sub {
653 my ($self, $ref) = @_; 1090 my ($self, $ref) = @_;
654 1091
655 require Storable; 1092 require Storable unless $Storable::VERSION;
656 1093
657 pack "w/a*", Storable::nfreeze ($ref) 1094 pack "w/a*", Storable::nfreeze ($ref)
658}; 1095};
659 1096
660=back 1097=back
661 1098
662=item AnyEvent::Handle::register_write_type type => $coderef->($handle, @args) 1099=item $handle->push_shutdown
663 1100
664This function (not method) lets you add your own types to C<push_write>. 1101Sometimes you know you want to close the socket after writing your data
1102before it was actually written. One way to do that is to replace your
1103C<on_drain> handler by a callback that shuts down the socket (and set
1104C<low_water_mark> to C<0>). This method is a shorthand for just that, and
1105replaces the C<on_drain> callback with:
1106
1107 sub { shutdown $_[0]{fh}, 1 }
1108
1109This simply shuts down the write side and signals an EOF condition to the
1110the peer.
1111
1112You can rely on the normal read queue and C<on_eof> handling
1113afterwards. This is the cleanest way to close a connection.
1114
1115This method may invoke callbacks (and therefore the handle might be
1116destroyed after it returns).
1117
1118=cut
1119
1120sub push_shutdown {
1121 my ($self) = @_;
1122
1123 delete $self->{low_water_mark};
1124 $self->on_drain (sub { shutdown $_[0]{fh}, 1 });
1125}
1126
1127=item custom write types - Package::anyevent_write_type $handle, @args
1128
1129Instead of one of the predefined types, you can also specify the name of
1130a package. AnyEvent will try to load the package and then expects to find
1131a function named C<anyevent_write_type> inside. If it isn't found, it
1132progressively tries to load the parent package until it either finds the
1133function (good) or runs out of packages (bad).
1134
665Whenever the given C<type> is used, C<push_write> will invoke the code 1135Whenever the given C<type> is used, C<push_write> will the function with
666reference with the handle object and the remaining arguments. 1136the handle object and the remaining arguments.
667 1137
668The code reference is supposed to return a single octet string that will 1138The function is supposed to return a single octet string that will be
669be appended to the write buffer. 1139appended to the write buffer, so you can mentally treat this function as a
1140"arguments to on-the-wire-format" converter.
670 1141
671Note that this is a function, and all types registered this way will be 1142Example: implement a custom write type C<join> that joins the remaining
672global, so try to use unique names. 1143arguments using the first one.
1144
1145 $handle->push_write (My::Type => " ", 1,2,3);
1146
1147 # uses the following package, which can be defined in the "My::Type" or in
1148 # the "My" modules to be auto-loaded, or just about anywhere when the
1149 # My::Type::anyevent_write_type is defined before invoking it.
1150
1151 package My::Type;
1152
1153 sub anyevent_write_type {
1154 my ($handle, $delim, @args) = @_;
1155
1156 join $delim, @args
1157 }
673 1158
674=cut 1159=cut
675 1160
676############################################################################# 1161#############################################################################
677 1162
686ways, the "simple" way, using only C<on_read> and the "complex" way, using 1171ways, the "simple" way, using only C<on_read> and the "complex" way, using
687a queue. 1172a queue.
688 1173
689In the simple case, you just install an C<on_read> callback and whenever 1174In the simple case, you just install an C<on_read> callback and whenever
690new data arrives, it will be called. You can then remove some data (if 1175new data arrives, it will be called. You can then remove some data (if
691enough is there) from the read buffer (C<< $handle->rbuf >>). Or you cna 1176enough is there) from the read buffer (C<< $handle->rbuf >>). Or you can
692leave the data there if you want to accumulate more (e.g. when only a 1177leave the data there if you want to accumulate more (e.g. when only a
693partial message has been received so far). 1178partial message has been received so far), or change the read queue with
1179e.g. C<push_read>.
694 1180
695In the more complex case, you want to queue multiple callbacks. In this 1181In the more complex case, you want to queue multiple callbacks. In this
696case, AnyEvent::Handle will call the first queued callback each time new 1182case, AnyEvent::Handle will call the first queued callback each time new
697data arrives (also the first time it is queued) and removes it when it has 1183data arrives (also the first time it is queued) and remove it when it has
698done its job (see C<push_read>, below). 1184done its job (see C<push_read>, below).
699 1185
700This way you can, for example, push three line-reads, followed by reading 1186This way you can, for example, push three line-reads, followed by reading
701a chunk of data, and AnyEvent::Handle will execute them in order. 1187a chunk of data, and AnyEvent::Handle will execute them in order.
702 1188
759=cut 1245=cut
760 1246
761sub _drain_rbuf { 1247sub _drain_rbuf {
762 my ($self) = @_; 1248 my ($self) = @_;
763 1249
1250 # avoid recursion
1251 return if $self->{_skip_drain_rbuf};
764 local $self->{_in_drain} = 1; 1252 local $self->{_skip_drain_rbuf} = 1;
765
766 if (
767 defined $self->{rbuf_max}
768 && $self->{rbuf_max} < length $self->{rbuf}
769 ) {
770 $self->_error (&Errno::ENOSPC, 1), return;
771 }
772 1253
773 while () { 1254 while () {
774 # we need to use a separate tls read buffer, as we must not receive data while 1255 # we need to use a separate tls read buffer, as we must not receive data while
775 # we are draining the buffer, and this can only happen with TLS. 1256 # we are draining the buffer, and this can only happen with TLS.
776 $self->{rbuf} .= delete $self->{_tls_rbuf} if exists $self->{_tls_rbuf}; 1257 $self->{rbuf} .= delete $self->{_tls_rbuf}
1258 if exists $self->{_tls_rbuf};
777 1259
778 my $len = length $self->{rbuf}; 1260 my $len = length $self->{rbuf};
779 1261
780 if (my $cb = shift @{ $self->{_queue} }) { 1262 if (my $cb = shift @{ $self->{_queue} }) {
781 unless ($cb->($self)) { 1263 unless ($cb->($self)) {
782 if ($self->{_eof}) { 1264 # no progress can be made
783 # no progress can be made (not enough data and no data forthcoming) 1265 # (not enough data and no data forthcoming)
784 $self->_error (&Errno::EPIPE, 1), return; 1266 $self->_error (Errno::EPIPE, 1), return
785 } 1267 if $self->{_eof};
786 1268
787 unshift @{ $self->{_queue} }, $cb; 1269 unshift @{ $self->{_queue} }, $cb;
788 last; 1270 last;
789 } 1271 }
790 } elsif ($self->{on_read}) { 1272 } elsif ($self->{on_read}) {
797 && !@{ $self->{_queue} } # and the queue is still empty 1279 && !@{ $self->{_queue} } # and the queue is still empty
798 && $self->{on_read} # but we still have on_read 1280 && $self->{on_read} # but we still have on_read
799 ) { 1281 ) {
800 # no further data will arrive 1282 # no further data will arrive
801 # so no progress can be made 1283 # so no progress can be made
802 $self->_error (&Errno::EPIPE, 1), return 1284 $self->_error (Errno::EPIPE, 1), return
803 if $self->{_eof}; 1285 if $self->{_eof};
804 1286
805 last; # more data might arrive 1287 last; # more data might arrive
806 } 1288 }
807 } else { 1289 } else {
810 last; 1292 last;
811 } 1293 }
812 } 1294 }
813 1295
814 if ($self->{_eof}) { 1296 if ($self->{_eof}) {
815 if ($self->{on_eof}) { 1297 $self->{on_eof}
816 $self->{on_eof}($self) 1298 ? $self->{on_eof}($self)
817 } else { 1299 : $self->_error (0, 1, "Unexpected end-of-file");
818 $self->_error (0, 1); 1300
819 } 1301 return;
1302 }
1303
1304 if (
1305 defined $self->{rbuf_max}
1306 && $self->{rbuf_max} < length $self->{rbuf}
1307 ) {
1308 $self->_error (Errno::ENOSPC, 1), return;
820 } 1309 }
821 1310
822 # may need to restart read watcher 1311 # may need to restart read watcher
823 unless ($self->{_rw}) { 1312 unless ($self->{_rw}) {
824 $self->start_read 1313 $self->start_read
830 1319
831This replaces the currently set C<on_read> callback, or clears it (when 1320This replaces the currently set C<on_read> callback, or clears it (when
832the new callback is C<undef>). See the description of C<on_read> in the 1321the new callback is C<undef>). See the description of C<on_read> in the
833constructor. 1322constructor.
834 1323
1324This method may invoke callbacks (and therefore the handle might be
1325destroyed after it returns).
1326
835=cut 1327=cut
836 1328
837sub on_read { 1329sub on_read {
838 my ($self, $cb) = @_; 1330 my ($self, $cb) = @_;
839 1331
840 $self->{on_read} = $cb; 1332 $self->{on_read} = $cb;
841 $self->_drain_rbuf if $cb && !$self->{_in_drain}; 1333 $self->_drain_rbuf if $cb;
842} 1334}
843 1335
844=item $handle->rbuf 1336=item $handle->rbuf
845 1337
846Returns the read buffer (as a modifiable lvalue). 1338Returns the read buffer (as a modifiable lvalue). You can also access the
1339read buffer directly as the C<< ->{rbuf} >> member, if you want (this is
1340much faster, and no less clean).
847 1341
848You can access the read buffer directly as the C<< ->{rbuf} >> 1342The only operation allowed on the read buffer (apart from looking at it)
849member, if you want. However, the only operation allowed on the 1343is removing data from its beginning. Otherwise modifying or appending to
850read buffer (apart from looking at it) is removing data from its 1344it is not allowed and will lead to hard-to-track-down bugs.
851beginning. Otherwise modifying or appending to it is not allowed and will
852lead to hard-to-track-down bugs.
853 1345
854NOTE: The read buffer should only be used or modified if the C<on_read>, 1346NOTE: The read buffer should only be used or modified in the C<on_read>
855C<push_read> or C<unshift_read> methods are used. The other read methods 1347callback or when C<push_read> or C<unshift_read> are used with a single
856automatically manage the read buffer. 1348callback (i.e. untyped). Typed C<push_read> and C<unshift_read> methods
1349will manage the read buffer on their own.
857 1350
858=cut 1351=cut
859 1352
860sub rbuf : lvalue { 1353sub rbuf : lvalue {
861 $_[0]{rbuf} 1354 $_[0]{rbuf}
878 1371
879If enough data was available, then the callback must remove all data it is 1372If enough data was available, then the callback must remove all data it is
880interested in (which can be none at all) and return a true value. After returning 1373interested in (which can be none at all) and return a true value. After returning
881true, it will be removed from the queue. 1374true, it will be removed from the queue.
882 1375
1376These methods may invoke callbacks (and therefore the handle might be
1377destroyed after it returns).
1378
883=cut 1379=cut
884 1380
885our %RH; 1381our %RH;
886 1382
887sub register_read_type($$) { 1383sub register_read_type($$) {
893 my $cb = pop; 1389 my $cb = pop;
894 1390
895 if (@_) { 1391 if (@_) {
896 my $type = shift; 1392 my $type = shift;
897 1393
1394 $cb = ($RH{$type} ||= _load_func "$type\::anyevent_read_type"
898 $cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_read") 1395 or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::push_read")
899 ->($self, $cb, @_); 1396 ->($self, $cb, @_);
900 } 1397 }
901 1398
902 push @{ $self->{_queue} }, $cb; 1399 push @{ $self->{_queue} }, $cb;
903 $self->_drain_rbuf unless $self->{_in_drain}; 1400 $self->_drain_rbuf;
904} 1401}
905 1402
906sub unshift_read { 1403sub unshift_read {
907 my $self = shift; 1404 my $self = shift;
908 my $cb = pop; 1405 my $cb = pop;
909 1406
910 if (@_) { 1407 if (@_) {
911 my $type = shift; 1408 my $type = shift;
912 1409
1410 $cb = ($RH{$type} ||= _load_func "$type\::anyevent_read_type"
913 $cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::unshift_read") 1411 or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::unshift_read")
914 ->($self, $cb, @_); 1412 ->($self, $cb, @_);
915 } 1413 }
916 1414
917
918 unshift @{ $self->{_queue} }, $cb; 1415 unshift @{ $self->{_queue} }, $cb;
919 $self->_drain_rbuf unless $self->{_in_drain}; 1416 $self->_drain_rbuf;
920} 1417}
921 1418
922=item $handle->push_read (type => @args, $cb) 1419=item $handle->push_read (type => @args, $cb)
923 1420
924=item $handle->unshift_read (type => @args, $cb) 1421=item $handle->unshift_read (type => @args, $cb)
925 1422
926Instead of providing a callback that parses the data itself you can chose 1423Instead of providing a callback that parses the data itself you can chose
927between a number of predefined parsing formats, for chunks of data, lines 1424between a number of predefined parsing formats, for chunks of data, lines
928etc. 1425etc. You can also specify the (fully qualified) name of a package, in
1426which case AnyEvent tries to load the package and then expects to find the
1427C<anyevent_read_type> function inside (see "custom read types", below).
929 1428
930Predefined types are (if you have ideas for additional types, feel free to 1429Predefined types are (if you have ideas for additional types, feel free to
931drop by and tell us): 1430drop by and tell us):
932 1431
933=over 4 1432=over 4
939data. 1438data.
940 1439
941Example: read 2 bytes. 1440Example: read 2 bytes.
942 1441
943 $handle->push_read (chunk => 2, sub { 1442 $handle->push_read (chunk => 2, sub {
944 warn "yay ", unpack "H*", $_[1]; 1443 say "yay " . unpack "H*", $_[1];
945 }); 1444 });
946 1445
947=cut 1446=cut
948 1447
949register_read_type chunk => sub { 1448register_read_type chunk => sub {
983 if (@_ < 3) { 1482 if (@_ < 3) {
984 # this is more than twice as fast as the generic code below 1483 # this is more than twice as fast as the generic code below
985 sub { 1484 sub {
986 $_[0]{rbuf} =~ s/^([^\015\012]*)(\015?\012)// or return; 1485 $_[0]{rbuf} =~ s/^([^\015\012]*)(\015?\012)// or return;
987 1486
988 $cb->($_[0], $1, $2); 1487 $cb->($_[0], "$1", "$2");
989 1 1488 1
990 } 1489 }
991 } else { 1490 } else {
992 $eol = quotemeta $eol unless ref $eol; 1491 $eol = quotemeta $eol unless ref $eol;
993 $eol = qr|^(.*?)($eol)|s; 1492 $eol = qr|^(.*?)($eol)|s;
994 1493
995 sub { 1494 sub {
996 $_[0]{rbuf} =~ s/$eol// or return; 1495 $_[0]{rbuf} =~ s/$eol// or return;
997 1496
998 $cb->($_[0], $1, $2); 1497 $cb->($_[0], "$1", "$2");
999 1 1498 1
1000 } 1499 }
1001 } 1500 }
1002}; 1501};
1003 1502
1025the receive buffer when neither C<$accept> nor C<$reject> match, 1524the receive buffer when neither C<$accept> nor C<$reject> match,
1026and everything preceding and including the match will be accepted 1525and everything preceding and including the match will be accepted
1027unconditionally. This is useful to skip large amounts of data that you 1526unconditionally. This is useful to skip large amounts of data that you
1028know cannot be matched, so that the C<$accept> or C<$reject> regex do not 1527know cannot be matched, so that the C<$accept> or C<$reject> regex do not
1029have to start matching from the beginning. This is purely an optimisation 1528have to start matching from the beginning. This is purely an optimisation
1030and is usually worth only when you expect more than a few kilobytes. 1529and is usually worth it only when you expect more than a few kilobytes.
1031 1530
1032Example: expect a http header, which ends at C<\015\012\015\012>. Since we 1531Example: expect a http header, which ends at C<\015\012\015\012>. Since we
1033expect the header to be very large (it isn't in practise, but...), we use 1532expect the header to be very large (it isn't in practice, but...), we use
1034a skip regex to skip initial portions. The skip regex is tricky in that 1533a skip regex to skip initial portions. The skip regex is tricky in that
1035it only accepts something not ending in either \015 or \012, as these are 1534it only accepts something not ending in either \015 or \012, as these are
1036required for the accept regex. 1535required for the accept regex.
1037 1536
1038 $handle->push_read (regex => 1537 $handle->push_read (regex =>
1051 1550
1052 sub { 1551 sub {
1053 # accept 1552 # accept
1054 if ($$rbuf =~ $accept) { 1553 if ($$rbuf =~ $accept) {
1055 $data .= substr $$rbuf, 0, $+[0], ""; 1554 $data .= substr $$rbuf, 0, $+[0], "";
1056 $cb->($self, $data); 1555 $cb->($_[0], $data);
1057 return 1; 1556 return 1;
1058 } 1557 }
1059 1558
1060 # reject 1559 # reject
1061 if ($reject && $$rbuf =~ $reject) { 1560 if ($reject && $$rbuf =~ $reject) {
1062 $self->_error (&Errno::EBADMSG); 1561 $_[0]->_error (Errno::EBADMSG);
1063 } 1562 }
1064 1563
1065 # skip 1564 # skip
1066 if ($skip && $$rbuf =~ $skip) { 1565 if ($skip && $$rbuf =~ $skip) {
1067 $data .= substr $$rbuf, 0, $+[0], ""; 1566 $data .= substr $$rbuf, 0, $+[0], "";
1083 my ($self, $cb) = @_; 1582 my ($self, $cb) = @_;
1084 1583
1085 sub { 1584 sub {
1086 unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) { 1585 unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
1087 if ($_[0]{rbuf} =~ /[^0-9]/) { 1586 if ($_[0]{rbuf} =~ /[^0-9]/) {
1088 $self->_error (&Errno::EBADMSG); 1587 $_[0]->_error (Errno::EBADMSG);
1089 } 1588 }
1090 return; 1589 return;
1091 } 1590 }
1092 1591
1093 my $len = $1; 1592 my $len = $1;
1094 1593
1095 $self->unshift_read (chunk => $len, sub { 1594 $_[0]->unshift_read (chunk => $len, sub {
1096 my $string = $_[1]; 1595 my $string = $_[1];
1097 $_[0]->unshift_read (chunk => 1, sub { 1596 $_[0]->unshift_read (chunk => 1, sub {
1098 if ($_[1] eq ",") { 1597 if ($_[1] eq ",") {
1099 $cb->($_[0], $string); 1598 $cb->($_[0], $string);
1100 } else { 1599 } else {
1101 $self->_error (&Errno::EBADMSG); 1600 $_[0]->_error (Errno::EBADMSG);
1102 } 1601 }
1103 }); 1602 });
1104 }); 1603 });
1105 1604
1106 1 1605 1
1173=cut 1672=cut
1174 1673
1175register_read_type json => sub { 1674register_read_type json => sub {
1176 my ($self, $cb) = @_; 1675 my ($self, $cb) = @_;
1177 1676
1178 require JSON; 1677 my $json = $self->{json} ||= json_coder;
1179 1678
1180 my $data; 1679 my $data;
1181 my $rbuf = \$self->{rbuf}; 1680 my $rbuf = \$self->{rbuf};
1182 1681
1183 my $json = $self->{json} ||= JSON->new->utf8;
1184
1185 sub { 1682 sub {
1186 my $ref = eval { $json->incr_parse ($self->{rbuf}) }; 1683 my $ref = eval { $json->incr_parse ($_[0]{rbuf}) };
1187 1684
1188 if ($ref) { 1685 if ($ref) {
1189 $self->{rbuf} = $json->incr_text; 1686 $_[0]{rbuf} = $json->incr_text;
1190 $json->incr_text = ""; 1687 $json->incr_text = "";
1191 $cb->($self, $ref); 1688 $cb->($_[0], $ref);
1192 1689
1193 1 1690 1
1194 } elsif ($@) { 1691 } elsif ($@) {
1195 # error case 1692 # error case
1196 $json->incr_skip; 1693 $json->incr_skip;
1197 1694
1198 $self->{rbuf} = $json->incr_text; 1695 $_[0]{rbuf} = $json->incr_text;
1199 $json->incr_text = ""; 1696 $json->incr_text = "";
1200 1697
1201 $self->_error (&Errno::EBADMSG); 1698 $_[0]->_error (Errno::EBADMSG);
1202 1699
1203 () 1700 ()
1204 } else { 1701 } else {
1205 $self->{rbuf} = ""; 1702 $_[0]{rbuf} = "";
1206 1703
1207 () 1704 ()
1208 } 1705 }
1209 } 1706 }
1210}; 1707};
1220=cut 1717=cut
1221 1718
1222register_read_type storable => sub { 1719register_read_type storable => sub {
1223 my ($self, $cb) = @_; 1720 my ($self, $cb) = @_;
1224 1721
1225 require Storable; 1722 require Storable unless $Storable::VERSION;
1226 1723
1227 sub { 1724 sub {
1228 # when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method 1725 # when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
1229 defined (my $len = eval { unpack "w", $_[0]{rbuf} }) 1726 defined (my $len = eval { unpack "w", $_[0]{rbuf} })
1230 or return; 1727 or return;
1233 1730
1234 # bypass unshift if we already have the remaining chunk 1731 # bypass unshift if we already have the remaining chunk
1235 if ($format + $len <= length $_[0]{rbuf}) { 1732 if ($format + $len <= length $_[0]{rbuf}) {
1236 my $data = substr $_[0]{rbuf}, $format, $len; 1733 my $data = substr $_[0]{rbuf}, $format, $len;
1237 substr $_[0]{rbuf}, 0, $format + $len, ""; 1734 substr $_[0]{rbuf}, 0, $format + $len, "";
1735
1238 $cb->($_[0], Storable::thaw ($data)); 1736 eval { $cb->($_[0], Storable::thaw ($data)); 1 }
1737 or return $_[0]->_error (Errno::EBADMSG);
1239 } else { 1738 } else {
1240 # remove prefix 1739 # remove prefix
1241 substr $_[0]{rbuf}, 0, $format, ""; 1740 substr $_[0]{rbuf}, 0, $format, "";
1242 1741
1243 # read remaining chunk 1742 # read remaining chunk
1244 $_[0]->unshift_read (chunk => $len, sub { 1743 $_[0]->unshift_read (chunk => $len, sub {
1245 if (my $ref = eval { Storable::thaw ($_[1]) }) { 1744 eval { $cb->($_[0], Storable::thaw ($_[1])); 1 }
1246 $cb->($_[0], $ref);
1247 } else {
1248 $self->_error (&Errno::EBADMSG); 1745 or $_[0]->_error (Errno::EBADMSG);
1249 }
1250 }); 1746 });
1251 } 1747 }
1252 1748
1253 1 1749 1
1254 } 1750 }
1255}; 1751};
1256 1752
1257=back 1753=back
1258 1754
1259=item AnyEvent::Handle::register_read_type type => $coderef->($handle, $cb, @args) 1755=item custom read types - Package::anyevent_read_type $handle, $cb, @args
1260 1756
1261This function (not method) lets you add your own types to C<push_read>. 1757Instead of one of the predefined types, you can also specify the name
1758of a package. AnyEvent will try to load the package and then expects to
1759find a function named C<anyevent_read_type> inside. If it isn't found, it
1760progressively tries to load the parent package until it either finds the
1761function (good) or runs out of packages (bad).
1262 1762
1263Whenever the given C<type> is used, C<push_read> will invoke the code 1763Whenever this type is used, C<push_read> will invoke the function with the
1264reference with the handle object, the callback and the remaining 1764handle object, the original callback and the remaining arguments.
1265arguments.
1266 1765
1267The code reference is supposed to return a callback (usually a closure) 1766The function is supposed to return a callback (usually a closure) that
1268that works as a plain read callback (see C<< ->push_read ($cb) >>). 1767works as a plain read callback (see C<< ->push_read ($cb) >>), so you can
1768mentally treat the function as a "configurable read type to read callback"
1769converter.
1269 1770
1270It should invoke the passed callback when it is done reading (remember to 1771It should invoke the original callback when it is done reading (remember
1271pass C<$handle> as first argument as all other callbacks do that). 1772to pass C<$handle> as first argument as all other callbacks do that,
1773although there is no strict requirement on this).
1272 1774
1273Note that this is a function, and all types registered this way will be
1274global, so try to use unique names.
1275
1276For examples, see the source of this module (F<perldoc -m AnyEvent::Handle>, 1775For examples, see the source of this module (F<perldoc -m
1277search for C<register_read_type>)). 1776AnyEvent::Handle>, search for C<register_read_type>)).
1278 1777
1279=item $handle->stop_read 1778=item $handle->stop_read
1280 1779
1281=item $handle->start_read 1780=item $handle->start_read
1282 1781
1288Note that AnyEvent::Handle will automatically C<start_read> for you when 1787Note that AnyEvent::Handle will automatically C<start_read> for you when
1289you change the C<on_read> callback or push/unshift a read callback, and it 1788you change the C<on_read> callback or push/unshift a read callback, and it
1290will automatically C<stop_read> for you when neither C<on_read> is set nor 1789will automatically C<stop_read> for you when neither C<on_read> is set nor
1291there are any read requests in the queue. 1790there are any read requests in the queue.
1292 1791
1293These methods will have no effect when in TLS mode (as TLS doesn't support 1792In older versions of this module (<= 5.3), these methods had no effect,
1294half-duplex connections). 1793as TLS does not support half-duplex connections. In current versions they
1794work as expected, as this behaviour is required to avoid certain resource
1795attacks, where the program would be forced to read (and buffer) arbitrary
1796amounts of data before being able to send some data. The drawback is that
1797some readings of the the SSL/TLS specifications basically require this
1798attack to be working, as SSL/TLS implementations might stall sending data
1799during a rehandshake.
1800
1801As a guideline, during the initial handshake, you should not stop reading,
1802and as a client, it might cause problems, depending on your application.
1295 1803
1296=cut 1804=cut
1297 1805
1298sub stop_read { 1806sub stop_read {
1299 my ($self) = @_; 1807 my ($self) = @_;
1300 1808
1301 delete $self->{_rw} unless $self->{tls}; 1809 delete $self->{_rw};
1302} 1810}
1303 1811
1304sub start_read { 1812sub start_read {
1305 my ($self) = @_; 1813 my ($self) = @_;
1306 1814
1307 unless ($self->{_rw} || $self->{_eof}) { 1815 unless ($self->{_rw} || $self->{_eof} || !$self->{fh}) {
1308 Scalar::Util::weaken $self; 1816 Scalar::Util::weaken $self;
1309 1817
1310 $self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub { 1818 $self->{_rw} = AE::io $self->{fh}, 0, sub {
1311 my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf}); 1819 my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf});
1312 my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf; 1820 my $len = sysread $self->{fh}, $$rbuf, $self->{read_size}, length $$rbuf;
1313 1821
1314 if ($len > 0) { 1822 if ($len > 0) {
1315 $self->{_activity} = AnyEvent->now; 1823 $self->{_activity} = $self->{_ractivity} = AE::now;
1316 1824
1317 if ($self->{tls}) { 1825 if ($self->{tls}) {
1318 Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf); 1826 Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf);
1319 1827
1320 &_dotls ($self); 1828 &_dotls ($self);
1321 } else { 1829 } else {
1322 $self->_drain_rbuf unless $self->{_in_drain}; 1830 $self->_drain_rbuf;
1831 }
1832
1833 if ($len == $self->{read_size}) {
1834 $self->{read_size} *= 2;
1835 $self->{read_size} = $self->{max_read_size} || MAX_READ_SIZE
1836 if $self->{read_size} > ($self->{max_read_size} || MAX_READ_SIZE);
1323 } 1837 }
1324 1838
1325 } elsif (defined $len) { 1839 } elsif (defined $len) {
1326 delete $self->{_rw}; 1840 delete $self->{_rw};
1327 $self->{_eof} = 1; 1841 $self->{_eof} = 1;
1328 $self->_drain_rbuf unless $self->{_in_drain}; 1842 $self->_drain_rbuf;
1329 1843
1330 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) { 1844 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
1331 return $self->_error ($!, 1); 1845 return $self->_error ($!, 1);
1332 } 1846 }
1333 }); 1847 };
1848 }
1849}
1850
1851our $ERROR_SYSCALL;
1852our $ERROR_WANT_READ;
1853
1854sub _tls_error {
1855 my ($self, $err) = @_;
1856
1857 return $self->_error ($!, 1)
1858 if $err == Net::SSLeay::ERROR_SYSCALL ();
1859
1860 my $err =Net::SSLeay::ERR_error_string (Net::SSLeay::ERR_get_error ());
1861
1862 # reduce error string to look less scary
1863 $err =~ s/^error:[0-9a-fA-F]{8}:[^:]+:([^:]+):/\L$1: /;
1864
1865 if ($self->{_on_starttls}) {
1866 (delete $self->{_on_starttls})->($self, undef, $err);
1867 &_freetls;
1868 } else {
1869 &_freetls;
1870 $self->_error (Errno::EPROTO, 1, $err);
1334 } 1871 }
1335} 1872}
1336 1873
1337# poll the write BIO and send the data if applicable 1874# poll the write BIO and send the data if applicable
1875# also decode read data if possible
1876# this is basiclaly our TLS state machine
1877# more efficient implementations are possible with openssl,
1878# but not with the buggy and incomplete Net::SSLeay.
1338sub _dotls { 1879sub _dotls {
1339 my ($self) = @_; 1880 my ($self) = @_;
1340 1881
1341 my $tmp; 1882 my $tmp;
1342 1883
1343 if (length $self->{_tls_wbuf}) { 1884 if (length $self->{_tls_wbuf}) {
1344 while (($tmp = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) { 1885 while (($tmp = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) {
1345 substr $self->{_tls_wbuf}, 0, $tmp, ""; 1886 substr $self->{_tls_wbuf}, 0, $tmp, "";
1346 } 1887 }
1888
1889 $tmp = Net::SSLeay::get_error ($self->{tls}, $tmp);
1890 return $self->_tls_error ($tmp)
1891 if $tmp != $ERROR_WANT_READ
1892 && ($tmp != $ERROR_SYSCALL || $!);
1347 } 1893 }
1348 1894
1349 while (defined ($tmp = Net::SSLeay::read ($self->{tls}))) { 1895 while (defined ($tmp = Net::SSLeay::read ($self->{tls}))) {
1350 unless (length $tmp) { 1896 unless (length $tmp) {
1351 # let's treat SSL-eof as we treat normal EOF 1897 $self->{_on_starttls}
1352 delete $self->{_rw}; 1898 and (delete $self->{_on_starttls})->($self, undef, "EOF during handshake"); # ???
1353 $self->{_eof} = 1;
1354 &_freetls; 1899 &_freetls;
1900
1901 if ($self->{on_stoptls}) {
1902 $self->{on_stoptls}($self);
1903 return;
1904 } else {
1905 # let's treat SSL-eof as we treat normal EOF
1906 delete $self->{_rw};
1907 $self->{_eof} = 1;
1908 }
1355 } 1909 }
1356 1910
1357 $self->{_tls_rbuf} .= $tmp; 1911 $self->{_tls_rbuf} .= $tmp;
1358 $self->_drain_rbuf unless $self->{_in_drain}; 1912 $self->_drain_rbuf;
1359 $self->{tls} or return; # tls session might have gone away in callback 1913 $self->{tls} or return; # tls session might have gone away in callback
1360 } 1914 }
1361 1915
1362 $tmp = Net::SSLeay::get_error ($self->{tls}, -1); 1916 $tmp = Net::SSLeay::get_error ($self->{tls}, -1);
1363
1364 if ($tmp != Net::SSLeay::ERROR_WANT_READ ()) {
1365 if ($tmp == Net::SSLeay::ERROR_SYSCALL ()) {
1366 return $self->_error ($!, 1); 1917 return $self->_tls_error ($tmp)
1367 } elsif ($tmp == Net::SSLeay::ERROR_SSL ()) { 1918 if $tmp != $ERROR_WANT_READ
1368 return $self->_error (&Errno::EIO, 1); 1919 && ($tmp != $ERROR_SYSCALL || $!);
1369 }
1370
1371 # all other errors are fine for our purposes
1372 }
1373 1920
1374 while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) { 1921 while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) {
1375 $self->{wbuf} .= $tmp; 1922 $self->{wbuf} .= $tmp;
1376 $self->_drain_wbuf; 1923 $self->_drain_wbuf;
1924 $self->{tls} or return; # tls session might have gone away in callback
1377 } 1925 }
1926
1927 $self->{_on_starttls}
1928 and Net::SSLeay::state ($self->{tls}) == Net::SSLeay::ST_OK ()
1929 and (delete $self->{_on_starttls})->($self, 1, "TLS/SSL connection established");
1378} 1930}
1379 1931
1380=item $handle->starttls ($tls[, $tls_ctx]) 1932=item $handle->starttls ($tls[, $tls_ctx])
1381 1933
1382Instead of starting TLS negotiation immediately when the AnyEvent::Handle 1934Instead of starting TLS negotiation immediately when the AnyEvent::Handle
1383object is created, you can also do that at a later time by calling 1935object is created, you can also do that at a later time by calling
1384C<starttls>. 1936C<starttls>.
1385 1937
1938Starting TLS is currently an asynchronous operation - when you push some
1939write data and then call C<< ->starttls >> then TLS negotiation will start
1940immediately, after which the queued write data is then sent.
1941
1386The first argument is the same as the C<tls> constructor argument (either 1942The first argument is the same as the C<tls> constructor argument (either
1387C<"connect">, C<"accept"> or an existing Net::SSLeay object). 1943C<"connect">, C<"accept"> or an existing Net::SSLeay object).
1388 1944
1389The second argument is the optional C<Net::SSLeay::CTX> object that is 1945The second argument is the optional C<AnyEvent::TLS> object that is used
1390used when AnyEvent::Handle has to create its own TLS connection object. 1946when AnyEvent::Handle has to create its own TLS connection object, or
1947a hash reference with C<< key => value >> pairs that will be used to
1948construct a new context.
1391 1949
1392The TLS connection object will end up in C<< $handle->{tls} >> after this 1950The TLS connection object will end up in C<< $handle->{tls} >>, the TLS
1393call and can be used or changed to your liking. Note that the handshake 1951context in C<< $handle->{tls_ctx} >> after this call and can be used or
1394might have already started when this function returns. 1952changed to your liking. Note that the handshake might have already started
1953when this function returns.
1395 1954
1396If it an error to start a TLS handshake more than once per 1955Due to bugs in OpenSSL, it might or might not be possible to do multiple
1397AnyEvent::Handle object (this is due to bugs in OpenSSL). 1956handshakes on the same stream. It is best to not attempt to use the
1957stream after stopping TLS.
1398 1958
1959This method may invoke callbacks (and therefore the handle might be
1960destroyed after it returns).
1961
1399=cut 1962=cut
1963
1964our %TLS_CACHE; #TODO not yet documented, should we?
1400 1965
1401sub starttls { 1966sub starttls {
1402 my ($self, $ssl, $ctx) = @_; 1967 my ($self, $tls, $ctx) = @_;
1968
1969 Carp::croak "It is an error to call starttls on an AnyEvent::Handle object while TLS is already active, caught"
1970 if $self->{tls};
1971
1972 $self->{tls} = $tls;
1973 $self->{tls_ctx} = $ctx if @_ > 2;
1974
1975 return unless $self->{fh};
1403 1976
1404 require Net::SSLeay; 1977 require Net::SSLeay;
1405 1978
1406 Carp::croak "it is an error to call starttls more than once on an AnyEvent::Handle object" 1979 $ERROR_SYSCALL = Net::SSLeay::ERROR_SYSCALL ();
1407 if $self->{tls}; 1980 $ERROR_WANT_READ = Net::SSLeay::ERROR_WANT_READ ();
1981
1982 $tls = delete $self->{tls};
1983 $ctx = $self->{tls_ctx};
1984
1985 local $Carp::CarpLevel = 1; # skip ourselves when creating a new context or session
1986
1987 if ("HASH" eq ref $ctx) {
1988 require AnyEvent::TLS;
1989
1990 if ($ctx->{cache}) {
1991 my $key = $ctx+0;
1992 $ctx = $TLS_CACHE{$key} ||= new AnyEvent::TLS %$ctx;
1993 } else {
1994 $ctx = new AnyEvent::TLS %$ctx;
1995 }
1996 }
1408 1997
1409 if ($ssl eq "accept") { 1998 $self->{tls_ctx} = $ctx || TLS_CTX ();
1410 $ssl = Net::SSLeay::new ($ctx || TLS_CTX ()); 1999 $self->{tls} = $tls = $self->{tls_ctx}->_get_session ($tls, $self, $self->{peername});
1411 Net::SSLeay::set_accept_state ($ssl);
1412 } elsif ($ssl eq "connect") {
1413 $ssl = Net::SSLeay::new ($ctx || TLS_CTX ());
1414 Net::SSLeay::set_connect_state ($ssl);
1415 }
1416
1417 $self->{tls} = $ssl;
1418 2000
1419 # basically, this is deep magic (because SSL_read should have the same issues) 2001 # basically, this is deep magic (because SSL_read should have the same issues)
1420 # but the openssl maintainers basically said: "trust us, it just works". 2002 # but the openssl maintainers basically said: "trust us, it just works".
1421 # (unfortunately, we have to hardcode constants because the abysmally misdesigned 2003 # (unfortunately, we have to hardcode constants because the abysmally misdesigned
1422 # and mismaintained ssleay-module doesn't even offer them). 2004 # and mismaintained ssleay-module doesn't even offer them).
1426 # 2008 #
1427 # note that we do not try to keep the length constant between writes as we are required to do. 2009 # note that we do not try to keep the length constant between writes as we are required to do.
1428 # we assume that most (but not all) of this insanity only applies to non-blocking cases, 2010 # we assume that most (but not all) of this insanity only applies to non-blocking cases,
1429 # and we drive openssl fully in blocking mode here. Or maybe we don't - openssl seems to 2011 # and we drive openssl fully in blocking mode here. Or maybe we don't - openssl seems to
1430 # have identity issues in that area. 2012 # have identity issues in that area.
1431 Net::SSLeay::CTX_set_mode ($self->{tls}, 2013# Net::SSLeay::CTX_set_mode ($ssl,
1432 (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1) 2014# (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)
1433 | (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2)); 2015# | (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2));
2016 Net::SSLeay::CTX_set_mode ($tls, 1|2);
1434 2017
1435 $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); 2018 $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1436 $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); 2019 $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1437 2020
2021 Net::SSLeay::BIO_write ($self->{_rbio}, $self->{rbuf});
2022 $self->{rbuf} = "";
2023
1438 Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio}); 2024 Net::SSLeay::set_bio ($tls, $self->{_rbio}, $self->{_wbio});
2025
2026 $self->{_on_starttls} = sub { $_[0]{on_starttls}(@_) }
2027 if $self->{on_starttls};
1439 2028
1440 &_dotls; # need to trigger the initial handshake 2029 &_dotls; # need to trigger the initial handshake
1441 $self->start_read; # make sure we actually do read 2030 $self->start_read; # make sure we actually do read
1442} 2031}
1443 2032
1444=item $handle->stoptls 2033=item $handle->stoptls
1445 2034
1446Shuts down the SSL connection - this makes a proper EOF handshake by 2035Shuts down the SSL connection - this makes a proper EOF handshake by
1447sending a close notify to the other side, but since OpenSSL doesn't 2036sending a close notify to the other side, but since OpenSSL doesn't
1448support non-blocking shut downs, it is not possible to re-use the stream 2037support non-blocking shut downs, it is not guaranteed that you can re-use
1449afterwards. 2038the stream afterwards.
2039
2040This method may invoke callbacks (and therefore the handle might be
2041destroyed after it returns).
1450 2042
1451=cut 2043=cut
1452 2044
1453sub stoptls { 2045sub stoptls {
1454 my ($self) = @_; 2046 my ($self) = @_;
1455 2047
1456 if ($self->{tls}) { 2048 if ($self->{tls} && $self->{fh}) {
1457 Net::SSLeay::shutdown ($self->{tls}); 2049 Net::SSLeay::shutdown ($self->{tls});
1458 2050
1459 &_dotls; 2051 &_dotls;
1460 2052
1461 # we don't give a shit. no, we do, but we can't. no... 2053# # we don't give a shit. no, we do, but we can't. no...#d#
1462 # we, we... have to use openssl :/ 2054# # we, we... have to use openssl :/#d#
1463 &_freetls; 2055# &_freetls;#d#
1464 } 2056 }
1465} 2057}
1466 2058
1467sub _freetls { 2059sub _freetls {
1468 my ($self) = @_; 2060 my ($self) = @_;
1469 2061
1470 return unless $self->{tls}; 2062 return unless $self->{tls};
1471 2063
1472 Net::SSLeay::free (delete $self->{tls}); 2064 $self->{tls_ctx}->_put_session (delete $self->{tls})
2065 if $self->{tls} > 0;
1473 2066
1474 delete @$self{qw(_rbio _wbio _tls_wbuf)}; 2067 delete @$self{qw(_rbio _wbio _tls_wbuf _on_starttls)};
1475} 2068}
2069
2070=item $handle->resettls
2071
2072This rarely-used method simply resets and TLS state on the handle, usually
2073causing data loss.
2074
2075One case where it may be useful is when you want to skip over the data in
2076the stream but you are not interested in interpreting it, so data loss is
2077no concern.
2078
2079=cut
2080
2081*resettls = \&_freetls;
1476 2082
1477sub DESTROY { 2083sub DESTROY {
1478 my $self = shift; 2084 my ($self) = @_;
1479 2085
1480 &_freetls; 2086 &_freetls;
1481 2087
1482 my $linger = exists $self->{linger} ? $self->{linger} : 3600; 2088 my $linger = exists $self->{linger} ? $self->{linger} : 3600;
1483 2089
1484 if ($linger && length $self->{wbuf}) { 2090 if ($linger && length $self->{wbuf} && $self->{fh}) {
1485 my $fh = delete $self->{fh}; 2091 my $fh = delete $self->{fh};
1486 my $wbuf = delete $self->{wbuf}; 2092 my $wbuf = delete $self->{wbuf};
1487 2093
1488 my @linger; 2094 my @linger;
1489 2095
1490 push @linger, AnyEvent->io (fh => $fh, poll => "w", cb => sub { 2096 push @linger, AE::io $fh, 1, sub {
1491 my $len = syswrite $fh, $wbuf, length $wbuf; 2097 my $len = syswrite $fh, $wbuf, length $wbuf;
1492 2098
1493 if ($len > 0) { 2099 if ($len > 0) {
1494 substr $wbuf, 0, $len, ""; 2100 substr $wbuf, 0, $len, "";
1495 } else { 2101 } elsif (defined $len || ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK)) {
1496 @linger = (); # end 2102 @linger = (); # end
1497 } 2103 }
1498 }); 2104 };
1499 push @linger, AnyEvent->timer (after => $linger, cb => sub { 2105 push @linger, AE::timer $linger, 0, sub {
1500 @linger = (); 2106 @linger = ();
1501 }); 2107 };
1502 } 2108 }
1503} 2109}
1504 2110
1505=item $handle->destroy 2111=item $handle->destroy
1506 2112
1507Shuts down the handle object as much as possible - this call ensures that 2113Shuts down the handle object as much as possible - this call ensures that
1508no further callbacks will be invoked and resources will be freed as much 2114no further callbacks will be invoked and as many resources as possible
1509as possible. You must not call any methods on the object afterwards. 2115will be freed. Any method you will call on the handle object after
2116destroying it in this way will be silently ignored (and it will return the
2117empty list).
1510 2118
1511Normally, you can just "forget" any references to an AnyEvent::Handle 2119Normally, you can just "forget" any references to an AnyEvent::Handle
1512object and it will simply shut down. This works in fatal error and EOF 2120object and it will simply shut down. This works in fatal error and EOF
1513callbacks, as well as code outside. It does I<NOT> work in a read or write 2121callbacks, as well as code outside. It does I<NOT> work in a read or write
1514callback, so when you want to destroy the AnyEvent::Handle object from 2122callback, so when you want to destroy the AnyEvent::Handle object from
1515within such an callback. You I<MUST> call C<< ->destroy >> explicitly in 2123within such an callback. You I<MUST> call C<< ->destroy >> explicitly in
1516that case. 2124that case.
1517 2125
2126Destroying the handle object in this way has the advantage that callbacks
2127will be removed as well, so if those are the only reference holders (as
2128is common), then one doesn't need to do anything special to break any
2129reference cycles.
2130
1518The handle might still linger in the background and write out remaining 2131The handle might still linger in the background and write out remaining
1519data, as specified by the C<linger> option, however. 2132data, as specified by the C<linger> option, however.
1520 2133
1521=cut 2134=cut
1522 2135
1523sub destroy { 2136sub destroy {
1524 my ($self) = @_; 2137 my ($self) = @_;
1525 2138
1526 $self->DESTROY; 2139 $self->DESTROY;
1527 %$self = (); 2140 %$self = ();
2141 bless $self, "AnyEvent::Handle::destroyed";
1528} 2142}
2143
2144sub AnyEvent::Handle::destroyed::AUTOLOAD {
2145 #nop
2146}
2147
2148=item $handle->destroyed
2149
2150Returns false as long as the handle hasn't been destroyed by a call to C<<
2151->destroy >>, true otherwise.
2152
2153Can be useful to decide whether the handle is still valid after some
2154callback possibly destroyed the handle. For example, C<< ->push_write >>,
2155C<< ->starttls >> and other methods can call user callbacks, which in turn
2156can destroy the handle, so work can be avoided by checking sometimes:
2157
2158 $hdl->starttls ("accept");
2159 return if $hdl->destroyed;
2160 $hdl->push_write (...
2161
2162Note that the call to C<push_write> will silently be ignored if the handle
2163has been destroyed, so often you can just ignore the possibility of the
2164handle being destroyed.
2165
2166=cut
2167
2168sub destroyed { 0 }
2169sub AnyEvent::Handle::destroyed::destroyed { 1 }
1529 2170
1530=item AnyEvent::Handle::TLS_CTX 2171=item AnyEvent::Handle::TLS_CTX
1531 2172
1532This function creates and returns the Net::SSLeay::CTX object used by 2173This function creates and returns the AnyEvent::TLS object used by default
1533default for TLS mode. 2174for TLS mode.
1534 2175
1535The context is created like this: 2176The context is created by calling L<AnyEvent::TLS> without any arguments.
1536
1537 Net::SSLeay::load_error_strings;
1538 Net::SSLeay::SSLeay_add_ssl_algorithms;
1539 Net::SSLeay::randomize;
1540
1541 my $CTX = Net::SSLeay::CTX_new;
1542
1543 Net::SSLeay::CTX_set_options $CTX, Net::SSLeay::OP_ALL
1544 2177
1545=cut 2178=cut
1546 2179
1547our $TLS_CTX; 2180our $TLS_CTX;
1548 2181
1549sub TLS_CTX() { 2182sub TLS_CTX() {
1550 $TLS_CTX || do { 2183 $TLS_CTX ||= do {
1551 require Net::SSLeay; 2184 require AnyEvent::TLS;
1552 2185
1553 Net::SSLeay::load_error_strings (); 2186 new AnyEvent::TLS
1554 Net::SSLeay::SSLeay_add_ssl_algorithms ();
1555 Net::SSLeay::randomize ();
1556
1557 $TLS_CTX = Net::SSLeay::CTX_new ();
1558
1559 Net::SSLeay::CTX_set_options ($TLS_CTX, Net::SSLeay::OP_ALL ());
1560
1561 $TLS_CTX
1562 } 2187 }
1563} 2188}
1564 2189
1565=back 2190=back
1566 2191
1577 2202
1578It is only safe to "forget" the reference inside EOF or error callbacks, 2203It is only safe to "forget" the reference inside EOF or error callbacks,
1579from within all other callbacks, you need to explicitly call the C<< 2204from within all other callbacks, you need to explicitly call the C<<
1580->destroy >> method. 2205->destroy >> method.
1581 2206
2207=item Why is my C<on_eof> callback never called?
2208
2209Probably because your C<on_error> callback is being called instead: When
2210you have outstanding requests in your read queue, then an EOF is
2211considered an error as you clearly expected some data.
2212
2213To avoid this, make sure you have an empty read queue whenever your handle
2214is supposed to be "idle" (i.e. connection closes are O.K.). You can set
2215an C<on_read> handler that simply pushes the first read requests in the
2216queue.
2217
2218See also the next question, which explains this in a bit more detail.
2219
2220=item How can I serve requests in a loop?
2221
2222Most protocols consist of some setup phase (authentication for example)
2223followed by a request handling phase, where the server waits for requests
2224and handles them, in a loop.
2225
2226There are two important variants: The first (traditional, better) variant
2227handles requests until the server gets some QUIT command, causing it to
2228close the connection first (highly desirable for a busy TCP server). A
2229client dropping the connection is an error, which means this variant can
2230detect an unexpected detection close.
2231
2232To handle this case, always make sure you have a on-empty read queue, by
2233pushing the "read request start" handler on it:
2234
2235 # we assume a request starts with a single line
2236 my @start_request; @start_request = (line => sub {
2237 my ($hdl, $line) = @_;
2238
2239 ... handle request
2240
2241 # push next request read, possibly from a nested callback
2242 $hdl->push_read (@start_request);
2243 });
2244
2245 # auth done, now go into request handling loop
2246 # now push the first @start_request
2247 $hdl->push_read (@start_request);
2248
2249By always having an outstanding C<push_read>, the handle always expects
2250some data and raises the C<EPIPE> error when the connction is dropped
2251unexpectedly.
2252
2253The second variant is a protocol where the client can drop the connection
2254at any time. For TCP, this means that the server machine may run out of
2255sockets easier, and in general, it means you cannot distinguish a protocl
2256failure/client crash from a normal connection close. Nevertheless, these
2257kinds of protocols are common (and sometimes even the best solution to the
2258problem).
2259
2260Having an outstanding read request at all times is possible if you ignore
2261C<EPIPE> errors, but this doesn't help with when the client drops the
2262connection during a request, which would still be an error.
2263
2264A better solution is to push the initial request read in an C<on_read>
2265callback. This avoids an error, as when the server doesn't expect data
2266(i.e. is idly waiting for the next request, an EOF will not raise an
2267error, but simply result in an C<on_eof> callback. It is also a bit slower
2268and simpler:
2269
2270 # auth done, now go into request handling loop
2271 $hdl->on_read (sub {
2272 my ($hdl) = @_;
2273
2274 # called each time we receive data but the read queue is empty
2275 # simply start read the request
2276
2277 $hdl->push_read (line => sub {
2278 my ($hdl, $line) = @_;
2279
2280 ... handle request
2281
2282 # do nothing special when the request has been handled, just
2283 # let the request queue go empty.
2284 });
2285 });
2286
1582=item I get different callback invocations in TLS mode/Why can't I pause 2287=item I get different callback invocations in TLS mode/Why can't I pause
1583reading? 2288reading?
1584 2289
1585Unlike, say, TCP, TLS connections do not consist of two independent 2290Unlike, say, TCP, TLS connections do not consist of two independent
1586communication channels, one for each direction. Or put differently. The 2291communication channels, one for each direction. Or put differently, the
1587read and write directions are not independent of each other: you cannot 2292read and write directions are not independent of each other: you cannot
1588write data unless you are also prepared to read, and vice versa. 2293write data unless you are also prepared to read, and vice versa.
1589 2294
1590This can mean than, in TLS mode, you might get C<on_error> or C<on_eof> 2295This means that, in TLS mode, you might get C<on_error> or C<on_eof>
1591callback invocations when you are not expecting any read data - the reason 2296callback invocations when you are not expecting any read data - the reason
1592is that AnyEvent::Handle always reads in TLS mode. 2297is that AnyEvent::Handle always reads in TLS mode.
1593 2298
1594During the connection, you have to make sure that you always have a 2299During the connection, you have to make sure that you always have a
1595non-empty read-queue, or an C<on_read> watcher. At the end of the 2300non-empty read-queue, or an C<on_read> watcher. At the end of the
1605 2310
1606 $handle->on_read (sub { }); 2311 $handle->on_read (sub { });
1607 $handle->on_eof (undef); 2312 $handle->on_eof (undef);
1608 $handle->on_error (sub { 2313 $handle->on_error (sub {
1609 my $data = delete $_[0]{rbuf}; 2314 my $data = delete $_[0]{rbuf};
1610 undef $handle;
1611 }); 2315 });
2316
2317Note that this example removes the C<rbuf> member from the handle object,
2318which is not normally allowed by the API. It is expressly permitted in
2319this case only, as the handle object needs to be destroyed afterwards.
1612 2320
1613The reason to use C<on_error> is that TCP connections, due to latencies 2321The reason to use C<on_error> is that TCP connections, due to latencies
1614and packets loss, might get closed quite violently with an error, when in 2322and packets loss, might get closed quite violently with an error, when in
1615fact, all data has been received. 2323fact all data has been received.
1616 2324
1617It is usually better to use acknowledgements when transferring data, 2325It is usually better to use acknowledgements when transferring data,
1618to make sure the other side hasn't just died and you got the data 2326to make sure the other side hasn't just died and you got the data
1619intact. This is also one reason why so many internet protocols have an 2327intact. This is also one reason why so many internet protocols have an
1620explicit QUIT command. 2328explicit QUIT command.
1627C<low_water_mark> this will be called precisely when all data has been 2335C<low_water_mark> this will be called precisely when all data has been
1628written to the socket: 2336written to the socket:
1629 2337
1630 $handle->push_write (...); 2338 $handle->push_write (...);
1631 $handle->on_drain (sub { 2339 $handle->on_drain (sub {
1632 warn "all data submitted to the kernel\n"; 2340 AE::log debug => "All data submitted to the kernel.";
1633 undef $handle; 2341 undef $handle;
1634 }); 2342 });
1635 2343
2344If you just want to queue some data and then signal EOF to the other side,
2345consider using C<< ->push_shutdown >> instead.
2346
2347=item I want to contact a TLS/SSL server, I don't care about security.
2348
2349If your TLS server is a pure TLS server (e.g. HTTPS) that only speaks TLS,
2350connect to it and then create the AnyEvent::Handle with the C<tls>
2351parameter:
2352
2353 tcp_connect $host, $port, sub {
2354 my ($fh) = @_;
2355
2356 my $handle = new AnyEvent::Handle
2357 fh => $fh,
2358 tls => "connect",
2359 on_error => sub { ... };
2360
2361 $handle->push_write (...);
2362 };
2363
2364=item I want to contact a TLS/SSL server, I do care about security.
2365
2366Then you should additionally enable certificate verification, including
2367peername verification, if the protocol you use supports it (see
2368L<AnyEvent::TLS>, C<verify_peername>).
2369
2370E.g. for HTTPS:
2371
2372 tcp_connect $host, $port, sub {
2373 my ($fh) = @_;
2374
2375 my $handle = new AnyEvent::Handle
2376 fh => $fh,
2377 peername => $host,
2378 tls => "connect",
2379 tls_ctx => { verify => 1, verify_peername => "https" },
2380 ...
2381
2382Note that you must specify the hostname you connected to (or whatever
2383"peername" the protocol needs) as the C<peername> argument, otherwise no
2384peername verification will be done.
2385
2386The above will use the system-dependent default set of trusted CA
2387certificates. If you want to check against a specific CA, add the
2388C<ca_file> (or C<ca_cert>) arguments to C<tls_ctx>:
2389
2390 tls_ctx => {
2391 verify => 1,
2392 verify_peername => "https",
2393 ca_file => "my-ca-cert.pem",
2394 },
2395
2396=item I want to create a TLS/SSL server, how do I do that?
2397
2398Well, you first need to get a server certificate and key. You have
2399three options: a) ask a CA (buy one, use cacert.org etc.) b) create a
2400self-signed certificate (cheap. check the search engine of your choice,
2401there are many tutorials on the net) or c) make your own CA (tinyca2 is a
2402nice program for that purpose).
2403
2404Then create a file with your private key (in PEM format, see
2405L<AnyEvent::TLS>), followed by the certificate (also in PEM format). The
2406file should then look like this:
2407
2408 -----BEGIN RSA PRIVATE KEY-----
2409 ...header data
2410 ... lots of base64'y-stuff
2411 -----END RSA PRIVATE KEY-----
2412
2413 -----BEGIN CERTIFICATE-----
2414 ... lots of base64'y-stuff
2415 -----END CERTIFICATE-----
2416
2417The important bits are the "PRIVATE KEY" and "CERTIFICATE" parts. Then
2418specify this file as C<cert_file>:
2419
2420 tcp_server undef, $port, sub {
2421 my ($fh) = @_;
2422
2423 my $handle = new AnyEvent::Handle
2424 fh => $fh,
2425 tls => "accept",
2426 tls_ctx => { cert_file => "my-server-keycert.pem" },
2427 ...
2428
2429When you have intermediate CA certificates that your clients might not
2430know about, just append them to the C<cert_file>.
2431
1636=back 2432=back
1637
1638 2433
1639=head1 SUBCLASSING AnyEvent::Handle 2434=head1 SUBCLASSING AnyEvent::Handle
1640 2435
1641In many cases, you might want to subclass AnyEvent::Handle. 2436In many cases, you might want to subclass AnyEvent::Handle.
1642 2437
1659 2454
1660=item * all members not documented here and not prefixed with an underscore 2455=item * all members not documented here and not prefixed with an underscore
1661are free to use in subclasses. 2456are free to use in subclasses.
1662 2457
1663Of course, new versions of AnyEvent::Handle may introduce more "public" 2458Of course, new versions of AnyEvent::Handle may introduce more "public"
1664member variables, but thats just life, at least it is documented. 2459member variables, but that's just life. At least it is documented.
1665 2460
1666=back 2461=back
1667 2462
1668=head1 AUTHOR 2463=head1 AUTHOR
1669 2464
1670Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>. 2465Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>.
1671 2466
1672=cut 2467=cut
1673 2468
16741; # End of AnyEvent::Handle 24691
2470

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