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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 = 4.3;
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 {
32 $cv->broadcast; 15 my ($hdl, $fatal, $msg) = @_;
33 }, 16 AE::log error => "Got error $msg!";
17 $hdl->destroy;
18 $cv->send;
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
82=item on_eof => $cb->($handle) 116=item on_prepare => $cb->($handle)
83 117
84Set the callback to be called when an end-of-file condition is detected, 118This (rarely used) callback is called before a new connection is
85i.e. in the case of a socket, when the other side has closed the 119attempted, but after the file handle has been created (you can access that
86connection cleanly. 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).
87 123
88For sockets, this just means that the other side has stopped sending data, 124The return value of this callback should be the connect timeout value in
89you can still try to write data, and, in fact, one can return from the eof 125seconds (or C<0>, or C<undef>, or the empty list, to indicate that the
90callback and continue writing data, as only the read part has been shut 126default timeout is to be used).
91down.
92 127
93While not mandatory, it is I<highly> recommended to set an eof callback, 128=item on_connect => $cb->($handle, $host, $port, $retry->())
94otherwise you might end up with a closed socket while you are still
95waiting for data.
96 129
97If an EOF condition has been detected but no C<on_eof> callback has been 130This callback is called when a connection has been successfully established.
98set, then a fatal error will be raised with C<$!> set to <0>.
99 131
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
100=item on_error => $cb->($handle, $fatal) 160=item on_error => $cb->($handle, $fatal, $message)
101 161
102This is the error callback, which is called when, well, some error 162This is the error callback, which is called when, well, some error
103occured, such as not being able to resolve the hostname, failure to 163occured, such as not being able to resolve the hostname, failure to
104connect or a read error. 164connect, or a read error.
105 165
106Some errors are fatal (which is indicated by C<$fatal> being true). On 166Some errors are fatal (which is indicated by C<$fatal> being true). On
107fatal errors the handle object will be shut down and will not be usable 167fatal errors the handle object will be destroyed (by a call to C<< ->
108(but you are free to look at the current C<< ->rbuf >>). Examples of fatal 168destroy >>) after invoking the error callback (which means you are free to
109errors are an EOF condition with active (but unsatisifable) read watchers 169examine the handle object). Examples of fatal errors are an EOF condition
110(C<EPIPE>) or I/O errors. 170with active (but unsatisfiable) read watchers (C<EPIPE>) or I/O errors. In
171cases where the other side can close the connection at will, it is
172often easiest to not report C<EPIPE> errors in this callback.
111 173
174AnyEvent::Handle tries to find an appropriate error code for you to check
175against, but in some cases (TLS errors), this does not work well. It is
176recommended to always output the C<$message> argument in human-readable
177error messages (it's usually the same as C<"$!">).
178
112Non-fatal errors can be retried by simply returning, but it is recommended 179Non-fatal errors can be retried by returning, but it is recommended
113to simply ignore this parameter and instead abondon the handle object 180to simply ignore this parameter and instead abondon the handle object
114when this callback is invoked. Examples of non-fatal errors are timeouts 181when this callback is invoked. Examples of non-fatal errors are timeouts
115C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>). 182C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>).
116 183
117On callback entrance, the value of C<$!> contains the operating system 184On entry to the callback, the value of C<$!> contains the operating
118error (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT> or C<EBADMSG>). 185system error code (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT>, C<EBADMSG> or
186C<EPROTO>).
119 187
120While not mandatory, it is I<highly> recommended to set this callback, as 188While not mandatory, it is I<highly> recommended to set this callback, as
121you will not be notified of errors otherwise. The default simply calls 189you will not be notified of errors otherwise. The default just calls
122C<croak>. 190C<croak>.
123 191
124=item on_read => $cb->($handle) 192=item on_read => $cb->($handle)
125 193
126This sets the default read callback, which is called when data arrives 194This sets the default read callback, which is called when data arrives
127and no read request is in the queue (unlike read queue callbacks, this 195and 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 196callback will only be called when at least one octet of data is in the
129read buffer). 197read buffer).
130 198
131To access (and remove data from) the read buffer, use the C<< ->rbuf >> 199To access (and remove data from) the read buffer, use the C<< ->rbuf >>
132method or access the C<$handle->{rbuf}> member directly. 200method or access the C<< $handle->{rbuf} >> member directly. Note that you
201must not enlarge or modify the read buffer, you can only remove data at
202the beginning from it.
133 203
204You can also call C<< ->push_read (...) >> or any other function that
205modifies the read queue. Or do both. Or ...
206
134When an EOF condition is detected then AnyEvent::Handle will first try to 207When an EOF condition is detected, AnyEvent::Handle will first try to
135feed all the remaining data to the queued callbacks and C<on_read> before 208feed all the remaining data to the queued callbacks and C<on_read> before
136calling the C<on_eof> callback. If no progress can be made, then a fatal 209calling the C<on_eof> callback. If no progress can be made, then a fatal
137error will be raised (with C<$!> set to C<EPIPE>). 210error will be raised (with C<$!> set to C<EPIPE>).
138 211
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
217=item on_eof => $cb->($handle)
218
219Set the callback to be called when an end-of-file condition is detected,
220i.e. in the case of a socket, when the other side has closed the
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).
224
225For sockets, this just means that the other side has stopped sending data,
226you can still try to write data, and, in fact, one can return from the EOF
227callback and continue writing data, as only the read part has been shut
228down.
229
230If an EOF condition has been detected but no C<on_eof> callback has been
231set, then a fatal error will be raised with C<$!> set to <0>.
232
139=item on_drain => $cb->($handle) 233=item on_drain => $cb->($handle)
140 234
141This 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
142(or when the callback is set and the buffer is empty already). 236empty (and immediately when the handle object is created).
143 237
144To append to the write buffer, use the C<< ->push_write >> method. 238To append to the write buffer, use the C<< ->push_write >> method.
145 239
146This 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
147into 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
149memory 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
150the file when the write queue becomes empty. 244the file when the write queue becomes empty.
151 245
152=item timeout => $fractional_seconds 246=item timeout => $fractional_seconds
153 247
248=item rtimeout => $fractional_seconds
249
250=item wtimeout => $fractional_seconds
251
154If non-zero, then this enables an "inactivity" timeout: whenever this many 252If non-zero, then these enables an "inactivity" timeout: whenever this
155seconds pass without a successful read or write on the underlying file 253many seconds pass without a successful read or write on the underlying
156handle, 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
157missing, 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).
158 257
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
159Note 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
160any outstanding read or write requests: If you plan to keep the connection 266outstanding read or write requests: If you plan to keep the connection
161idle then you should disable the timout temporarily or ignore the timeout 267idle then you should disable the timeout temporarily or ignore the
162in the C<on_timeout> callback, in which case AnyEvent::Handle will simply 268timeout in the corresponding C<on_timeout> callback, in which case
163restart the timeout. 269AnyEvent::Handle will simply restart the timeout.
164 270
165Zero (the default) disables this timeout. 271Zero (the default) disables the corresponding timeout.
166 272
167=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)
168 278
169Called whenever the inactivity timeout passes. If you return from this 279Called whenever the inactivity timeout passes. If you return from this
170callback, 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,
171so this condition is not fatal in any way. 281so this condition is not fatal in any way.
172 282
180be 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
181(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
182amount 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
183isn't finished). 293isn't finished).
184 294
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
185=item autocork => <boolean> 310=item autocork => <boolean>
186 311
187When disabled (the default), then C<push_write> will try to immediately 312When disabled (the default), C<push_write> will try to immediately
188write 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
189a 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
190be inefficient if you write multiple small chunks (on the wire, this 315be inefficient if you write multiple small chunks (on the wire, this
191disadvantage is usually avoided by your kernel's nagle algorithm, see 316disadvantage is usually avoided by your kernel's nagle algorithm, see
192C<no_delay>, but this option can save costly syscalls). 317C<no_delay>, but this option can save costly syscalls).
193 318
194When enabled, then writes will always be queued till the next event loop 319When enabled, writes will always be queued till the next event loop
195iteration. This is efficient when you do many small writes per iteration, 320iteration. This is efficient when you do many small writes per iteration,
196but 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
197the write buffer often is full). It also increases write latency. 322the write buffer often is full). It also increases write latency.
198 323
199=item no_delay => <boolean> 324=item no_delay => <boolean>
203the Nagle algorithm, and usually it is beneficial. 328the Nagle algorithm, and usually it is beneficial.
204 329
205In 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
206accomplishd by setting this option to a true value. 331accomplishd by setting this option to a true value.
207 332
208The default is your opertaing system's default behaviour (most likely 333The default is your operating system's default behaviour (most likely
209enabled), 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.
210 367
211=item read_size => <bytes> 368=item read_size => <bytes>
212 369
213The default read block size (the amount of bytes this module will 370The initial read block size, the number of bytes this module will try
214try to read during each loop iteration, which affects memory 371to read during each loop iteration. Each handle object will consume
215requirements). 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.
216 382
217=item low_water_mark => <bytes> 383=item low_water_mark => <bytes>
218 384
219Sets 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
220buffer: 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
221considered empty. 387considered empty.
222 388
223Sometimes it can be beneficial (for performance reasons) to add data to 389Sometimes it can be beneficial (for performance reasons) to add data to
224the 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
225the operating system kernel usually buffers data as well, so the default 391the operating system kernel usually buffers data as well, so the default
226is good in almost all cases. 392is good in almost all cases.
227 393
228=item linger => <seconds> 394=item linger => <seconds>
229 395
230If non-zero (default: C<3600>), then the destructor of the 396If this is non-zero (default: C<3600>), the destructor of the
231AnyEvent::Handle object will check whether there is still outstanding 397AnyEvent::Handle object will check whether there is still outstanding
232write 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
233socket. No errors will be reported (this mostly matches how the operating 399socket. No errors will be reported (this mostly matches how the operating
234system treats outstanding data at socket close time). 400system treats outstanding data at socket close time).
235 401
236This 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
237yet. 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
238help. 404help.
239 405
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
240=item tls => "accept" | "connect" | Net::SSLeay::SSL object 416=item tls => "accept" | "connect" | Net::SSLeay::SSL object
241 417
242When this parameter is given, it enables TLS (SSL) mode, that means 418When this parameter is given, it enables TLS (SSL) mode, that means
243AnyEvent 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
244established 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.
245 424
246TLS mode requires Net::SSLeay to be installed (it will be loaded 425TLS mode requires Net::SSLeay to be installed (it will be loaded
247automatically 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
248have 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
249to add the dependency yourself. 428to add the dependency yourself.
253mode. 432mode.
254 433
255You can also provide your own TLS connection object, but you have 434You can also provide your own TLS connection object, but you have
256to 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>
257or 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
258AnyEvent::Handle. 437AnyEvent::Handle. Also, this module will take ownership of this connection
438object.
259 439
440At some future point, AnyEvent::Handle might switch to another TLS
441implementation, then the option to use your own session object will go
442away.
443
444B<IMPORTANT:> since Net::SSLeay "objects" are really only integers,
445passing in the wrong integer will lead to certain crash. This most often
446happens when one uses a stylish C<< tls => 1 >> and is surprised about the
447segmentation fault.
448
260See 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.
261 450
262=item tls_ctx => $ssl_ctx 451=item tls_ctx => $anyevent_tls
263 452
264Use 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
265(unless a connection object was specified directly). If this parameter is 454(unless a connection object was specified directly). If this
266missing, 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.
267 493
268=item json => JSON or JSON::XS object 494=item json => JSON or JSON::XS object
269 495
270This 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.
271 497
280 506
281=cut 507=cut
282 508
283sub new { 509sub new {
284 my $class = shift; 510 my $class = shift;
285
286 my $self = bless { @_ }, $class; 511 my $self = bless { @_ }, $class;
287 512
288 $self->{fh} or Carp::croak "mandatory argument fh is missing"; 513 if ($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;
289 584
290 AnyEvent::Util::fh_nonblocking $self->{fh}, 1; 585 AnyEvent::Util::fh_nonblocking $self->{fh}, 1;
291 586
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
292 $self->starttls (delete $self->{tls}, delete $self->{tls_ctx}) 604 $self->starttls (delete $self->{tls}, delete $self->{tls_ctx})
293 if $self->{tls}; 605 if $self->{tls};
294 606
295 $self->{_activity} = AnyEvent->now;
296 $self->_timeout;
297
298 $self->on_drain (delete $self->{on_drain}) if exists $self->{on_drain}; 607 $self->on_drain (delete $self->{on_drain} ) if $self->{on_drain};
299 $self->no_delay (delete $self->{no_delay}) if exists $self->{no_delay};
300 608
301 $self->start_read 609 $self->start_read
302 if $self->{on_read}; 610 if $self->{on_read} || @{ $self->{_queue} };
303 611
304 $self 612 $self->_drain_wbuf;
305}
306
307sub _shutdown {
308 my ($self) = @_;
309
310 delete $self->{_tw};
311 delete $self->{_rw};
312 delete $self->{_ww};
313 delete $self->{fh};
314
315 &_freetls;
316
317 delete $self->{on_read};
318 delete $self->{_queue};
319} 613}
320 614
321sub _error { 615sub _error {
322 my ($self, $errno, $fatal) = @_; 616 my ($self, $errno, $fatal, $message) = @_;
323
324 $self->_shutdown
325 if $fatal;
326 617
327 $! = $errno; 618 $! = $errno;
619 $message ||= "$!";
328 620
329 if ($self->{on_error}) { 621 if ($self->{on_error}) {
330 $self->{on_error}($self, $fatal); 622 $self->{on_error}($self, $fatal, $message);
331 } else { 623 $self->destroy if $fatal;
624 } elsif ($self->{fh} || $self->{connect}) {
625 $self->destroy;
332 Carp::croak "AnyEvent::Handle uncaught error: $!"; 626 Carp::croak "AnyEvent::Handle uncaught error: $message";
333 } 627 }
334} 628}
335 629
336=item $fh = $handle->fh 630=item $fh = $handle->fh
337 631
361 $_[0]{on_eof} = $_[1]; 655 $_[0]{on_eof} = $_[1];
362} 656}
363 657
364=item $handle->on_timeout ($cb) 658=item $handle->on_timeout ($cb)
365 659
366Replace the current C<on_timeout> callback, or disables the callback (but 660=item $handle->on_rtimeout ($cb)
367not the timeout) if C<$cb> = C<undef>. See the C<timeout> constructor
368argument and method.
369 661
370=cut 662=item $handle->on_wtimeout ($cb)
371 663
372sub on_timeout { 664Replace the current C<on_timeout>, C<on_rtimeout> or C<on_wtimeout>
373 $_[0]{on_timeout} = $_[1]; 665callback, or disables the callback (but not the timeout) if C<$cb> =
374} 666C<undef>. See the C<timeout> constructor argument and method.
667
668=cut
669
670# see below
375 671
376=item $handle->autocork ($boolean) 672=item $handle->autocork ($boolean)
377 673
378Enables or disables the current autocork behaviour (see C<autocork> 674Enables or disables the current autocork behaviour (see C<autocork>
379constructor argument). 675constructor argument). Changes will only take effect on the next write.
380 676
381=cut 677=cut
678
679sub autocork {
680 $_[0]{autocork} = $_[1];
681}
382 682
383=item $handle->no_delay ($boolean) 683=item $handle->no_delay ($boolean)
384 684
385Enables or disables the C<no_delay> setting (see constructor argument of 685Enables or disables the C<no_delay> setting (see constructor argument of
386the same name for details). 686the same name for details).
388=cut 688=cut
389 689
390sub no_delay { 690sub no_delay {
391 $_[0]{no_delay} = $_[1]; 691 $_[0]{no_delay} = $_[1];
392 692
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
393 eval { 707 eval {
394 local $SIG{__DIE__}; 708 local $SIG{__DIE__};
395 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};
396 }; 711 };
397} 712}
398 713
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
399############################################################################# 786#############################################################################
400 787
401=item $handle->timeout ($seconds) 788=item $handle->timeout ($seconds)
402 789
790=item $handle->rtimeout ($seconds)
791
792=item $handle->wtimeout ($seconds)
793
403Configures (or disables) the inactivity timeout. 794Configures (or disables) the inactivity timeout.
404 795
405=cut 796The timeout will be checked instantly, so this method might destroy the
797handle before it returns.
406 798
407sub 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 {
408 my ($self, $timeout) = @_; 823 my ($self, $new_value) = @_;
409 824
825 $new_value >= 0
826 or Carp::croak "AnyEvent::Handle->$timeout called with negative timeout ($new_value), caught";
827
410 $self->{timeout} = $timeout; 828 $self->{$timeout} = $new_value;
411 $self->_timeout; 829 delete $self->{$tw}; &$cb;
412} 830 };
413 831
832 *{"${dir}timeout_reset"} = sub {
833 $_[0]{$activity} = AE::now;
834 };
835
836 # main workhorse:
414# reset the timeout watcher, as neccessary 837 # reset the timeout watcher, as neccessary
415# also check for time-outs 838 # also check for time-outs
416sub _timeout { 839 $cb = sub {
417 my ($self) = @_; 840 my ($self) = @_;
418 841
419 if ($self->{timeout}) { 842 if ($self->{$timeout} && $self->{fh}) {
420 my $NOW = AnyEvent->now; 843 my $NOW = AE::now;
421 844
422 # when would the timeout trigger? 845 # when would the timeout trigger?
423 my $after = $self->{_activity} + $self->{timeout} - $NOW; 846 my $after = $self->{$activity} + $self->{$timeout} - $NOW;
424 847
425 # now or in the past already? 848 # now or in the past already?
426 if ($after <= 0) { 849 if ($after <= 0) {
427 $self->{_activity} = $NOW; 850 $self->{$activity} = $NOW;
428 851
429 if ($self->{on_timeout}) { 852 if ($self->{$on_timeout}) {
430 $self->{on_timeout}($self); 853 $self->{$on_timeout}($self);
431 } else { 854 } else {
432 $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};
433 } 863 }
434 864
435 # callback could have changed timeout value, optimise 865 Scalar::Util::weaken $self;
436 return unless $self->{timeout}; 866 return unless $self; # ->error could have destroyed $self
437 867
438 # calculate new after 868 $self->{$tw} ||= AE::timer $after, 0, sub {
439 $after = $self->{timeout}; 869 delete $self->{$tw};
870 $cb->($self);
871 };
872 } else {
873 delete $self->{$tw};
440 } 874 }
441
442 Scalar::Util::weaken $self;
443 return unless $self; # ->error could have destroyed $self
444
445 $self->{_tw} ||= AnyEvent->timer (after => $after, cb => sub {
446 delete $self->{_tw};
447 $self->_timeout;
448 });
449 } else {
450 delete $self->{_tw};
451 } 875 }
452} 876}
453 877
454############################################################################# 878#############################################################################
455 879
462 886
463The 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
464AnyEvent::Handle will automatically try to get rid of it for you. 888AnyEvent::Handle will automatically try to get rid of it for you.
465 889
466When 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
467water mark, the C<on_drain> callback will be invoked. 891water mark, the C<on_drain> callback will be invoked once.
468 892
469=over 4 893=over 4
470 894
471=item $handle->on_drain ($cb) 895=item $handle->on_drain ($cb)
472 896
473Sets 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
474C<on_drain> in the constructor). 898C<on_drain> in the constructor).
475 899
900This method may invoke callbacks (and therefore the handle might be
901destroyed after it returns).
902
476=cut 903=cut
477 904
478sub on_drain { 905sub on_drain {
479 my ($self, $cb) = @_; 906 my ($self, $cb) = @_;
480 907
484 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});
485} 912}
486 913
487=item $handle->push_write ($data) 914=item $handle->push_write ($data)
488 915
489Queues 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
490want (only limited by the available memory), as C<AnyEvent::Handle> 917you want (only limited by the available memory and C<wbuf_max>), as
491buffers 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).
492 922
493=cut 923=cut
494 924
495sub _drain_wbuf { 925sub _drain_wbuf {
496 my ($self) = @_; 926 my ($self) = @_;
500 Scalar::Util::weaken $self; 930 Scalar::Util::weaken $self;
501 931
502 my $cb = sub { 932 my $cb = sub {
503 my $len = syswrite $self->{fh}, $self->{wbuf}; 933 my $len = syswrite $self->{fh}, $self->{wbuf};
504 934
505 if ($len >= 0) { 935 if (defined $len) {
506 substr $self->{wbuf}, 0, $len, ""; 936 substr $self->{wbuf}, 0, $len, "";
507 937
508 $self->{_activity} = AnyEvent->now; 938 $self->{_activity} = $self->{_wactivity} = AE::now;
509 939
510 $self->{on_drain}($self) 940 $self->{on_drain}($self)
511 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})
512 && $self->{on_drain}; 942 && $self->{on_drain};
513 943
519 949
520 # try to write data immediately 950 # try to write data immediately
521 $cb->() unless $self->{autocork}; 951 $cb->() unless $self->{autocork};
522 952
523 # if still data left in wbuf, we need to poll 953 # if still data left in wbuf, we need to poll
524 $self->{_ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb) 954 $self->{_ww} = AE::io $self->{fh}, 1, $cb
525 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 }
526 }; 963 };
527} 964}
528 965
529our %WH; 966our %WH;
530 967
968# deprecated
531sub register_write_type($$) { 969sub register_write_type($$) {
532 $WH{$_[0]} = $_[1]; 970 $WH{$_[0]} = $_[1];
533} 971}
534 972
535sub push_write { 973sub push_write {
536 my $self = shift; 974 my $self = shift;
537 975
538 if (@_ > 1) { 976 if (@_ > 1) {
539 my $type = shift; 977 my $type = shift;
540 978
979 @_ = ($WH{$type} ||= _load_func "$type\::anyevent_write_type"
541 @_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write") 980 or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::push_write")
542 ->($self, @_); 981 ->($self, @_);
543 } 982 }
544 983
984 # we downgrade here to avoid hard-to-track-down bugs,
985 # and diagnose the problem earlier and better.
986
545 if ($self->{tls}) { 987 if ($self->{tls}) {
546 $self->{_tls_wbuf} .= $_[0]; 988 utf8::downgrade $self->{_tls_wbuf} .= $_[0];
547 989 &_dotls ($self) if $self->{fh};
548 &_dotls ($self);
549 } else { 990 } else {
550 $self->{wbuf} .= $_[0]; 991 utf8::downgrade $self->{wbuf} .= $_[0];
551 $self->_drain_wbuf; 992 $self->_drain_wbuf if $self->{fh};
552 } 993 }
553} 994}
554 995
555=item $handle->push_write (type => @args) 996=item $handle->push_write (type => @args)
556 997
557Instead of formatting your data yourself, you can also let this module do 998Instead of formatting your data yourself, you can also let this module
558the job by specifying a type and type-specific arguments. 999do the job by specifying a type and type-specific arguments. You
1000can also specify the (fully qualified) name of a package, in which
1001case AnyEvent tries to load the package and then expects to find the
1002C<anyevent_write_type> function inside (see "custom write types", below).
559 1003
560Predefined types are (if you have ideas for additional types, feel free to 1004Predefined types are (if you have ideas for additional types, feel free to
561drop by and tell us): 1005drop by and tell us):
562 1006
563=over 4 1007=over 4
620Other languages could read single lines terminated by a newline and pass 1064Other languages could read single lines terminated by a newline and pass
621this line into their JSON decoder of choice. 1065this line into their JSON decoder of choice.
622 1066
623=cut 1067=cut
624 1068
1069sub json_coder() {
1070 eval { require JSON::XS; JSON::XS->new->utf8 }
1071 || do { require JSON; JSON->new->utf8 }
1072}
1073
625register_write_type json => sub { 1074register_write_type json => sub {
626 my ($self, $ref) = @_; 1075 my ($self, $ref) = @_;
627 1076
628 require JSON; 1077 my $json = $self->{json} ||= json_coder;
629 1078
630 $self->{json} ? $self->{json}->encode ($ref) 1079 $json->encode ($ref)
631 : JSON::encode_json ($ref)
632}; 1080};
633 1081
634=item storable => $reference 1082=item storable => $reference
635 1083
636Freezes the given reference using L<Storable> and writes it to the 1084Freezes the given reference using L<Storable> and writes it to the
639=cut 1087=cut
640 1088
641register_write_type storable => sub { 1089register_write_type storable => sub {
642 my ($self, $ref) = @_; 1090 my ($self, $ref) = @_;
643 1091
644 require Storable; 1092 require Storable unless $Storable::VERSION;
645 1093
646 pack "w/a*", Storable::nfreeze ($ref) 1094 pack "w/a*", Storable::nfreeze ($ref)
647}; 1095};
648 1096
649=back 1097=back
650 1098
651=item AnyEvent::Handle::register_write_type type => $coderef->($handle, @args) 1099=item $handle->push_shutdown
652 1100
653This 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
654Whenever 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
655reference with the handle object and the remaining arguments. 1136the handle object and the remaining arguments.
656 1137
657The 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
658be 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.
659 1141
660Note 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
661global, 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 }
662 1158
663=cut 1159=cut
664 1160
665############################################################################# 1161#############################################################################
666 1162
675ways, 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
676a queue. 1172a queue.
677 1173
678In 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
679new 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
680enough is there) from the read buffer (C<< $handle->rbuf >>). Or you cna 1176enough is there) from the read buffer (C<< $handle->rbuf >>). Or you can
681leave the data there if you want to accumulate more (e.g. when only a 1177leave the data there if you want to accumulate more (e.g. when only a
682partial message has been received so far). 1178partial message has been received so far), or change the read queue with
1179e.g. C<push_read>.
683 1180
684In the more complex case, you want to queue multiple callbacks. In this 1181In the more complex case, you want to queue multiple callbacks. In this
685case, AnyEvent::Handle will call the first queued callback each time new 1182case, AnyEvent::Handle will call the first queued callback each time new
686data arrives (also the first time it is queued) and removes it when it has 1183data arrives (also the first time it is queued) and remove it when it has
687done its job (see C<push_read>, below). 1184done its job (see C<push_read>, below).
688 1185
689This way you can, for example, push three line-reads, followed by reading 1186This way you can, for example, push three line-reads, followed by reading
690a chunk of data, and AnyEvent::Handle will execute them in order. 1187a chunk of data, and AnyEvent::Handle will execute them in order.
691 1188
748=cut 1245=cut
749 1246
750sub _drain_rbuf { 1247sub _drain_rbuf {
751 my ($self) = @_; 1248 my ($self) = @_;
752 1249
1250 # avoid recursion
1251 return if $self->{_skip_drain_rbuf};
753 local $self->{_in_drain} = 1; 1252 local $self->{_skip_drain_rbuf} = 1;
754
755 if (
756 defined $self->{rbuf_max}
757 && $self->{rbuf_max} < length $self->{rbuf}
758 ) {
759 $self->_error (&Errno::ENOSPC, 1), return;
760 }
761 1253
762 while () { 1254 while () {
1255 # we need to use a separate tls read buffer, as we must not receive data while
1256 # we are draining the buffer, and this can only happen with TLS.
1257 $self->{rbuf} .= delete $self->{_tls_rbuf}
1258 if exists $self->{_tls_rbuf};
1259
763 my $len = length $self->{rbuf}; 1260 my $len = length $self->{rbuf};
764 1261
765 if (my $cb = shift @{ $self->{_queue} }) { 1262 if (my $cb = shift @{ $self->{_queue} }) {
766 unless ($cb->($self)) { 1263 unless ($cb->($self)) {
767 if ($self->{_eof}) { 1264 # no progress can be made
768 # no progress can be made (not enough data and no data forthcoming) 1265 # (not enough data and no data forthcoming)
769 $self->_error (&Errno::EPIPE, 1), return; 1266 $self->_error (Errno::EPIPE, 1), return
770 } 1267 if $self->{_eof};
771 1268
772 unshift @{ $self->{_queue} }, $cb; 1269 unshift @{ $self->{_queue} }, $cb;
773 last; 1270 last;
774 } 1271 }
775 } elsif ($self->{on_read}) { 1272 } elsif ($self->{on_read}) {
782 && !@{ $self->{_queue} } # and the queue is still empty 1279 && !@{ $self->{_queue} } # and the queue is still empty
783 && $self->{on_read} # but we still have on_read 1280 && $self->{on_read} # but we still have on_read
784 ) { 1281 ) {
785 # no further data will arrive 1282 # no further data will arrive
786 # so no progress can be made 1283 # so no progress can be made
787 $self->_error (&Errno::EPIPE, 1), return 1284 $self->_error (Errno::EPIPE, 1), return
788 if $self->{_eof}; 1285 if $self->{_eof};
789 1286
790 last; # more data might arrive 1287 last; # more data might arrive
791 } 1288 }
792 } else { 1289 } else {
795 last; 1292 last;
796 } 1293 }
797 } 1294 }
798 1295
799 if ($self->{_eof}) { 1296 if ($self->{_eof}) {
800 if ($self->{on_eof}) { 1297 $self->{on_eof}
801 $self->{on_eof}($self) 1298 ? $self->{on_eof}($self)
802 } else { 1299 : $self->_error (0, 1, "Unexpected end-of-file");
803 $self->_error (0, 1); 1300
804 } 1301 return;
1302 }
1303
1304 if (
1305 defined $self->{rbuf_max}
1306 && $self->{rbuf_max} < length $self->{rbuf}
1307 ) {
1308 $self->_error (Errno::ENOSPC, 1), return;
805 } 1309 }
806 1310
807 # may need to restart read watcher 1311 # may need to restart read watcher
808 unless ($self->{_rw}) { 1312 unless ($self->{_rw}) {
809 $self->start_read 1313 $self->start_read
815 1319
816This replaces the currently set C<on_read> callback, or clears it (when 1320This replaces the currently set C<on_read> callback, or clears it (when
817the new callback is C<undef>). See the description of C<on_read> in the 1321the new callback is C<undef>). See the description of C<on_read> in the
818constructor. 1322constructor.
819 1323
1324This method may invoke callbacks (and therefore the handle might be
1325destroyed after it returns).
1326
820=cut 1327=cut
821 1328
822sub on_read { 1329sub on_read {
823 my ($self, $cb) = @_; 1330 my ($self, $cb) = @_;
824 1331
825 $self->{on_read} = $cb; 1332 $self->{on_read} = $cb;
826 $self->_drain_rbuf if $cb && !$self->{_in_drain}; 1333 $self->_drain_rbuf if $cb;
827} 1334}
828 1335
829=item $handle->rbuf 1336=item $handle->rbuf
830 1337
831Returns 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).
832 1341
833You can access the read buffer directly as the C<< ->{rbuf} >> member, if 1342The only operation allowed on the read buffer (apart from looking at it)
834you want. 1343is removing data from its beginning. Otherwise modifying or appending to
1344it is not allowed and will lead to hard-to-track-down bugs.
835 1345
836NOTE: 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>
837C<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
838automatically 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.
839 1350
840=cut 1351=cut
841 1352
842sub rbuf : lvalue { 1353sub rbuf : lvalue {
843 $_[0]{rbuf} 1354 $_[0]{rbuf}
860 1371
861If 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
862interested 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
863true, it will be removed from the queue. 1374true, it will be removed from the queue.
864 1375
1376These methods may invoke callbacks (and therefore the handle might be
1377destroyed after it returns).
1378
865=cut 1379=cut
866 1380
867our %RH; 1381our %RH;
868 1382
869sub register_read_type($$) { 1383sub register_read_type($$) {
875 my $cb = pop; 1389 my $cb = pop;
876 1390
877 if (@_) { 1391 if (@_) {
878 my $type = shift; 1392 my $type = shift;
879 1393
1394 $cb = ($RH{$type} ||= _load_func "$type\::anyevent_read_type"
880 $cb = ($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")
881 ->($self, $cb, @_); 1396 ->($self, $cb, @_);
882 } 1397 }
883 1398
884 push @{ $self->{_queue} }, $cb; 1399 push @{ $self->{_queue} }, $cb;
885 $self->_drain_rbuf unless $self->{_in_drain}; 1400 $self->_drain_rbuf;
886} 1401}
887 1402
888sub unshift_read { 1403sub unshift_read {
889 my $self = shift; 1404 my $self = shift;
890 my $cb = pop; 1405 my $cb = pop;
891 1406
892 if (@_) { 1407 if (@_) {
893 my $type = shift; 1408 my $type = shift;
894 1409
1410 $cb = ($RH{$type} ||= _load_func "$type\::anyevent_read_type"
895 $cb = ($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")
896 ->($self, $cb, @_); 1412 ->($self, $cb, @_);
897 } 1413 }
898 1414
899
900 unshift @{ $self->{_queue} }, $cb; 1415 unshift @{ $self->{_queue} }, $cb;
901 $self->_drain_rbuf unless $self->{_in_drain}; 1416 $self->_drain_rbuf;
902} 1417}
903 1418
904=item $handle->push_read (type => @args, $cb) 1419=item $handle->push_read (type => @args, $cb)
905 1420
906=item $handle->unshift_read (type => @args, $cb) 1421=item $handle->unshift_read (type => @args, $cb)
907 1422
908Instead 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
909between a number of predefined parsing formats, for chunks of data, lines 1424between a number of predefined parsing formats, for chunks of data, lines
910etc. 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).
911 1428
912Predefined 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
913drop by and tell us): 1430drop by and tell us):
914 1431
915=over 4 1432=over 4
921data. 1438data.
922 1439
923Example: read 2 bytes. 1440Example: read 2 bytes.
924 1441
925 $handle->push_read (chunk => 2, sub { 1442 $handle->push_read (chunk => 2, sub {
926 warn "yay ", unpack "H*", $_[1]; 1443 say "yay " . unpack "H*", $_[1];
927 }); 1444 });
928 1445
929=cut 1446=cut
930 1447
931register_read_type chunk => sub { 1448register_read_type chunk => sub {
965 if (@_ < 3) { 1482 if (@_ < 3) {
966 # 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
967 sub { 1484 sub {
968 $_[0]{rbuf} =~ s/^([^\015\012]*)(\015?\012)// or return; 1485 $_[0]{rbuf} =~ s/^([^\015\012]*)(\015?\012)// or return;
969 1486
970 $cb->($_[0], $1, $2); 1487 $cb->($_[0], "$1", "$2");
971 1 1488 1
972 } 1489 }
973 } else { 1490 } else {
974 $eol = quotemeta $eol unless ref $eol; 1491 $eol = quotemeta $eol unless ref $eol;
975 $eol = qr|^(.*?)($eol)|s; 1492 $eol = qr|^(.*?)($eol)|s;
976 1493
977 sub { 1494 sub {
978 $_[0]{rbuf} =~ s/$eol// or return; 1495 $_[0]{rbuf} =~ s/$eol// or return;
979 1496
980 $cb->($_[0], $1, $2); 1497 $cb->($_[0], "$1", "$2");
981 1 1498 1
982 } 1499 }
983 } 1500 }
984}; 1501};
985 1502
1007the receive buffer when neither C<$accept> nor C<$reject> match, 1524the receive buffer when neither C<$accept> nor C<$reject> match,
1008and everything preceding and including the match will be accepted 1525and everything preceding and including the match will be accepted
1009unconditionally. This is useful to skip large amounts of data that you 1526unconditionally. This is useful to skip large amounts of data that you
1010know cannot be matched, so that the C<$accept> or C<$reject> regex do not 1527know cannot be matched, so that the C<$accept> or C<$reject> regex do not
1011have to start matching from the beginning. This is purely an optimisation 1528have to start matching from the beginning. This is purely an optimisation
1012and 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.
1013 1530
1014Example: 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
1015expect 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
1016a 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
1017it 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
1018required for the accept regex. 1535required for the accept regex.
1019 1536
1020 $handle->push_read (regex => 1537 $handle->push_read (regex =>
1033 1550
1034 sub { 1551 sub {
1035 # accept 1552 # accept
1036 if ($$rbuf =~ $accept) { 1553 if ($$rbuf =~ $accept) {
1037 $data .= substr $$rbuf, 0, $+[0], ""; 1554 $data .= substr $$rbuf, 0, $+[0], "";
1038 $cb->($self, $data); 1555 $cb->($_[0], $data);
1039 return 1; 1556 return 1;
1040 } 1557 }
1041 1558
1042 # reject 1559 # reject
1043 if ($reject && $$rbuf =~ $reject) { 1560 if ($reject && $$rbuf =~ $reject) {
1044 $self->_error (&Errno::EBADMSG); 1561 $_[0]->_error (Errno::EBADMSG);
1045 } 1562 }
1046 1563
1047 # skip 1564 # skip
1048 if ($skip && $$rbuf =~ $skip) { 1565 if ($skip && $$rbuf =~ $skip) {
1049 $data .= substr $$rbuf, 0, $+[0], ""; 1566 $data .= substr $$rbuf, 0, $+[0], "";
1065 my ($self, $cb) = @_; 1582 my ($self, $cb) = @_;
1066 1583
1067 sub { 1584 sub {
1068 unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) { 1585 unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
1069 if ($_[0]{rbuf} =~ /[^0-9]/) { 1586 if ($_[0]{rbuf} =~ /[^0-9]/) {
1070 $self->_error (&Errno::EBADMSG); 1587 $_[0]->_error (Errno::EBADMSG);
1071 } 1588 }
1072 return; 1589 return;
1073 } 1590 }
1074 1591
1075 my $len = $1; 1592 my $len = $1;
1076 1593
1077 $self->unshift_read (chunk => $len, sub { 1594 $_[0]->unshift_read (chunk => $len, sub {
1078 my $string = $_[1]; 1595 my $string = $_[1];
1079 $_[0]->unshift_read (chunk => 1, sub { 1596 $_[0]->unshift_read (chunk => 1, sub {
1080 if ($_[1] eq ",") { 1597 if ($_[1] eq ",") {
1081 $cb->($_[0], $string); 1598 $cb->($_[0], $string);
1082 } else { 1599 } else {
1083 $self->_error (&Errno::EBADMSG); 1600 $_[0]->_error (Errno::EBADMSG);
1084 } 1601 }
1085 }); 1602 });
1086 }); 1603 });
1087 1604
1088 1 1605 1
1135 } 1652 }
1136}; 1653};
1137 1654
1138=item json => $cb->($handle, $hash_or_arrayref) 1655=item json => $cb->($handle, $hash_or_arrayref)
1139 1656
1140Reads a JSON object or array, decodes it and passes it to the callback. 1657Reads a JSON object or array, decodes it and passes it to the
1658callback. When a parse error occurs, an C<EBADMSG> error will be raised.
1141 1659
1142If a C<json> object was passed to the constructor, then that will be used 1660If a C<json> object was passed to the constructor, then that will be used
1143for the final decode, otherwise it will create a JSON coder expecting UTF-8. 1661for the final decode, otherwise it will create a JSON coder expecting UTF-8.
1144 1662
1145This read type uses the incremental parser available with JSON version 1663This read type uses the incremental parser available with JSON version
1154=cut 1672=cut
1155 1673
1156register_read_type json => sub { 1674register_read_type json => sub {
1157 my ($self, $cb) = @_; 1675 my ($self, $cb) = @_;
1158 1676
1159 require JSON; 1677 my $json = $self->{json} ||= json_coder;
1160 1678
1161 my $data; 1679 my $data;
1162 my $rbuf = \$self->{rbuf}; 1680 my $rbuf = \$self->{rbuf};
1163 1681
1164 my $json = $self->{json} ||= JSON->new->utf8;
1165
1166 sub { 1682 sub {
1167 my $ref = $json->incr_parse ($self->{rbuf}); 1683 my $ref = eval { $json->incr_parse ($_[0]{rbuf}) };
1168 1684
1169 if ($ref) { 1685 if ($ref) {
1170 $self->{rbuf} = $json->incr_text; 1686 $_[0]{rbuf} = $json->incr_text;
1171 $json->incr_text = ""; 1687 $json->incr_text = "";
1172 $cb->($self, $ref); 1688 $cb->($_[0], $ref);
1173 1689
1174 1 1690 1
1691 } elsif ($@) {
1692 # error case
1693 $json->incr_skip;
1694
1695 $_[0]{rbuf} = $json->incr_text;
1696 $json->incr_text = "";
1697
1698 $_[0]->_error (Errno::EBADMSG);
1699
1700 ()
1175 } else { 1701 } else {
1176 $self->{rbuf} = ""; 1702 $_[0]{rbuf} = "";
1703
1177 () 1704 ()
1178 } 1705 }
1179 } 1706 }
1180}; 1707};
1181 1708
1190=cut 1717=cut
1191 1718
1192register_read_type storable => sub { 1719register_read_type storable => sub {
1193 my ($self, $cb) = @_; 1720 my ($self, $cb) = @_;
1194 1721
1195 require Storable; 1722 require Storable unless $Storable::VERSION;
1196 1723
1197 sub { 1724 sub {
1198 # 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
1199 defined (my $len = eval { unpack "w", $_[0]{rbuf} }) 1726 defined (my $len = eval { unpack "w", $_[0]{rbuf} })
1200 or return; 1727 or return;
1203 1730
1204 # bypass unshift if we already have the remaining chunk 1731 # bypass unshift if we already have the remaining chunk
1205 if ($format + $len <= length $_[0]{rbuf}) { 1732 if ($format + $len <= length $_[0]{rbuf}) {
1206 my $data = substr $_[0]{rbuf}, $format, $len; 1733 my $data = substr $_[0]{rbuf}, $format, $len;
1207 substr $_[0]{rbuf}, 0, $format + $len, ""; 1734 substr $_[0]{rbuf}, 0, $format + $len, "";
1735
1208 $cb->($_[0], Storable::thaw ($data)); 1736 eval { $cb->($_[0], Storable::thaw ($data)); 1 }
1737 or return $_[0]->_error (Errno::EBADMSG);
1209 } else { 1738 } else {
1210 # remove prefix 1739 # remove prefix
1211 substr $_[0]{rbuf}, 0, $format, ""; 1740 substr $_[0]{rbuf}, 0, $format, "";
1212 1741
1213 # read remaining chunk 1742 # read remaining chunk
1214 $_[0]->unshift_read (chunk => $len, sub { 1743 $_[0]->unshift_read (chunk => $len, sub {
1215 if (my $ref = eval { Storable::thaw ($_[1]) }) { 1744 eval { $cb->($_[0], Storable::thaw ($_[1])); 1 }
1216 $cb->($_[0], $ref);
1217 } else {
1218 $self->_error (&Errno::EBADMSG); 1745 or $_[0]->_error (Errno::EBADMSG);
1219 }
1220 }); 1746 });
1221 } 1747 }
1222 1748
1223 1 1749 1
1224 } 1750 }
1225}; 1751};
1226 1752
1227=back 1753=back
1228 1754
1229=item AnyEvent::Handle::register_read_type type => $coderef->($handle, $cb, @args) 1755=item custom read types - Package::anyevent_read_type $handle, $cb, @args
1230 1756
1231This function (not method) lets you add your own types to C<push_read>. 1757Instead of one of the predefined types, you can also specify the name
1758of a package. AnyEvent will try to load the package and then expects to
1759find a function named C<anyevent_read_type> inside. If it isn't found, it
1760progressively tries to load the parent package until it either finds the
1761function (good) or runs out of packages (bad).
1232 1762
1233Whenever the given C<type> is used, C<push_read> will invoke the code 1763Whenever this type is used, C<push_read> will invoke the function with the
1234reference with the handle object, the callback and the remaining 1764handle object, the original callback and the remaining arguments.
1235arguments.
1236 1765
1237The code reference is supposed to return a callback (usually a closure) 1766The function is supposed to return a callback (usually a closure) that
1238that works as a plain read callback (see C<< ->push_read ($cb) >>). 1767works as a plain read callback (see C<< ->push_read ($cb) >>), so you can
1768mentally treat the function as a "configurable read type to read callback"
1769converter.
1239 1770
1240It should invoke the passed callback when it is done reading (remember to 1771It should invoke the original callback when it is done reading (remember
1241pass C<$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).
1242 1774
1243Note that this is a function, and all types registered this way will be
1244global, so try to use unique names.
1245
1246For examples, see the source of this module (F<perldoc -m AnyEvent::Handle>, 1775For examples, see the source of this module (F<perldoc -m
1247search for C<register_read_type>)). 1776AnyEvent::Handle>, search for C<register_read_type>)).
1248 1777
1249=item $handle->stop_read 1778=item $handle->stop_read
1250 1779
1251=item $handle->start_read 1780=item $handle->start_read
1252 1781
1258Note that AnyEvent::Handle will automatically C<start_read> for you when 1787Note that AnyEvent::Handle will automatically C<start_read> for you when
1259you change the C<on_read> callback or push/unshift a read callback, and it 1788you change the C<on_read> callback or push/unshift a read callback, and it
1260will automatically C<stop_read> for you when neither C<on_read> is set nor 1789will automatically C<stop_read> for you when neither C<on_read> is set nor
1261there are any read requests in the queue. 1790there are any read requests in the queue.
1262 1791
1263These methods will have no effect when in TLS mode (as TLS doesn't support 1792In older versions of this module (<= 5.3), these methods had no effect,
1264half-duplex connections). 1793as TLS does not support half-duplex connections. In current versions they
1794work as expected, as this behaviour is required to avoid certain resource
1795attacks, where the program would be forced to read (and buffer) arbitrary
1796amounts of data before being able to send some data. The drawback is that
1797some readings of the the SSL/TLS specifications basically require this
1798attack to be working, as SSL/TLS implementations might stall sending data
1799during a rehandshake.
1800
1801As a guideline, during the initial handshake, you should not stop reading,
1802and as a client, it might cause problems, depending on your application.
1265 1803
1266=cut 1804=cut
1267 1805
1268sub stop_read { 1806sub stop_read {
1269 my ($self) = @_; 1807 my ($self) = @_;
1270 1808
1271 delete $self->{_rw} unless $self->{tls}; 1809 delete $self->{_rw};
1272} 1810}
1273 1811
1274sub start_read { 1812sub start_read {
1275 my ($self) = @_; 1813 my ($self) = @_;
1276 1814
1277 unless ($self->{_rw} || $self->{_eof}) { 1815 unless ($self->{_rw} || $self->{_eof} || !$self->{fh}) {
1278 Scalar::Util::weaken $self; 1816 Scalar::Util::weaken $self;
1279 1817
1280 $self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub { 1818 $self->{_rw} = AE::io $self->{fh}, 0, sub {
1281 my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf}); 1819 my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf});
1282 my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf; 1820 my $len = sysread $self->{fh}, $$rbuf, $self->{read_size}, length $$rbuf;
1283 1821
1284 if ($len > 0) { 1822 if ($len > 0) {
1285 $self->{_activity} = AnyEvent->now; 1823 $self->{_activity} = $self->{_ractivity} = AE::now;
1286 1824
1287 if ($self->{tls}) { 1825 if ($self->{tls}) {
1288 Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf); 1826 Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf);
1289 1827
1290 &_dotls ($self); 1828 &_dotls ($self);
1291 } else { 1829 } else {
1292 $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);
1293 } 1837 }
1294 1838
1295 } elsif (defined $len) { 1839 } elsif (defined $len) {
1296 delete $self->{_rw}; 1840 delete $self->{_rw};
1297 $self->{_eof} = 1; 1841 $self->{_eof} = 1;
1298 $self->_drain_rbuf unless $self->{_in_drain}; 1842 $self->_drain_rbuf;
1299 1843
1300 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) { 1844 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
1301 return $self->_error ($!, 1); 1845 return $self->_error ($!, 1);
1302 } 1846 }
1303 }); 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, $err);
1304 } 1871 }
1305} 1872}
1306 1873
1307# poll the write BIO and send the data if applicable 1874# poll the write BIO and send the data if applicable
1875# also decode read data if possible
1876# this is basiclaly our TLS state machine
1877# more efficient implementations are possible with openssl,
1878# but not with the buggy and incomplete Net::SSLeay.
1308sub _dotls { 1879sub _dotls {
1309 my ($self) = @_; 1880 my ($self) = @_;
1310 1881
1311 my $tmp; 1882 my $tmp;
1312 1883
1313 if (length $self->{_tls_wbuf}) { 1884 if (length $self->{_tls_wbuf}) {
1314 while (($tmp = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) { 1885 while (($tmp = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) {
1315 substr $self->{_tls_wbuf}, 0, $tmp, ""; 1886 substr $self->{_tls_wbuf}, 0, $tmp, "";
1316 } 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 || $!);
1317 } 1893 }
1318 1894
1319 while (defined ($tmp = Net::SSLeay::read ($self->{tls}))) { 1895 while (defined ($tmp = Net::SSLeay::read ($self->{tls}))) {
1320 unless (length $tmp) { 1896 unless (length $tmp) {
1321 # let's treat SSL-eof as we treat normal EOF 1897 $self->{_on_starttls}
1322 delete $self->{_rw}; 1898 and (delete $self->{_on_starttls})->($self, undef, "EOF during handshake"); # ???
1323 $self->{_eof} = 1;
1324 &_freetls; 1899 &_freetls;
1900
1901 if ($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 }
1325 } 1909 }
1326 1910
1327 $self->{rbuf} .= $tmp; 1911 $self->{_tls_rbuf} .= $tmp;
1328 $self->_drain_rbuf unless $self->{_in_drain}; 1912 $self->_drain_rbuf;
1329 $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
1330 } 1914 }
1331 1915
1332 $tmp = Net::SSLeay::get_error ($self->{tls}, -1); 1916 $tmp = Net::SSLeay::get_error ($self->{tls}, -1);
1333
1334 if ($tmp != Net::SSLeay::ERROR_WANT_READ ()) {
1335 if ($tmp == Net::SSLeay::ERROR_SYSCALL ()) {
1336 return $self->_error ($!, 1); 1917 return $self->_tls_error ($tmp)
1337 } elsif ($tmp == Net::SSLeay::ERROR_SSL ()) { 1918 if $tmp != $ERROR_WANT_READ
1338 return $self->_error (&Errno::EIO, 1); 1919 && ($tmp != $ERROR_SYSCALL || $!);
1339 }
1340
1341 # all other errors are fine for our purposes
1342 }
1343 1920
1344 while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) { 1921 while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) {
1345 $self->{wbuf} .= $tmp; 1922 $self->{wbuf} .= $tmp;
1346 $self->_drain_wbuf; 1923 $self->_drain_wbuf;
1924 $self->{tls} or return; # tls session might have gone away in callback
1347 } 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");
1348} 1930}
1349 1931
1350=item $handle->starttls ($tls[, $tls_ctx]) 1932=item $handle->starttls ($tls[, $tls_ctx])
1351 1933
1352Instead of starting TLS negotiation immediately when the AnyEvent::Handle 1934Instead of starting TLS negotiation immediately when the AnyEvent::Handle
1353object 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
1354C<starttls>. 1936C<starttls>.
1355 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
1356The 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
1357C<"connect">, C<"accept"> or an existing Net::SSLeay object). 1943C<"connect">, C<"accept"> or an existing Net::SSLeay object).
1358 1944
1359The 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
1360used 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.
1361 1949
1362The 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
1363call and can be used or changed to your liking. Note that the handshake 1951context in C<< $handle->{tls_ctx} >> after this call and can be used or
1364might have already started when this function returns. 1952changed to your liking. Note that the handshake might have already started
1953when this function returns.
1365 1954
1366If it an error to start a TLS handshake more than once per 1955Due to bugs in OpenSSL, it might or might not be possible to do multiple
1367AnyEvent::Handle object (this is due to bugs in OpenSSL). 1956handshakes on the same stream. It is best to not attempt to use the
1957stream after stopping TLS.
1368 1958
1959This method may invoke callbacks (and therefore the handle might be
1960destroyed after it returns).
1961
1369=cut 1962=cut
1963
1964our %TLS_CACHE; #TODO not yet documented, should we?
1370 1965
1371sub starttls { 1966sub starttls {
1372 my ($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};
1373 1976
1374 require Net::SSLeay; 1977 require Net::SSLeay;
1375 1978
1376 Carp::croak "it is an error to call starttls more than once on an Anyevent::Handle object" 1979 $ERROR_SYSCALL = Net::SSLeay::ERROR_SYSCALL ();
1377 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 }
1378 1997
1379 if ($ssl eq "accept") { 1998 $self->{tls_ctx} = $ctx || TLS_CTX ();
1380 $ssl = Net::SSLeay::new ($ctx || TLS_CTX ()); 1999 $self->{tls} = $tls = $self->{tls_ctx}->_get_session ($tls, $self, $self->{peername});
1381 Net::SSLeay::set_accept_state ($ssl);
1382 } elsif ($ssl eq "connect") {
1383 $ssl = Net::SSLeay::new ($ctx || TLS_CTX ());
1384 Net::SSLeay::set_connect_state ($ssl);
1385 }
1386
1387 $self->{tls} = $ssl;
1388 2000
1389 # basically, this is deep magic (because SSL_read should have the same issues) 2001 # basically, this is deep magic (because SSL_read should have the same issues)
1390 # but the openssl maintainers basically said: "trust us, it just works". 2002 # but the openssl maintainers basically said: "trust us, it just works".
1391 # (unfortunately, we have to hardcode constants because the abysmally misdesigned 2003 # (unfortunately, we have to hardcode constants because the abysmally misdesigned
1392 # and mismaintained ssleay-module doesn't even offer them). 2004 # and mismaintained ssleay-module doesn't even offer them).
1396 # 2008 #
1397 # note that we do not try to keep the length constant between writes as we are required to do. 2009 # note that we do not try to keep the length constant between writes as we are required to do.
1398 # we assume that most (but not all) of this insanity only applies to non-blocking cases, 2010 # we assume that most (but not all) of this insanity only applies to non-blocking cases,
1399 # and we drive openssl fully in blocking mode here. Or maybe we don't - openssl seems to 2011 # and we drive openssl fully in blocking mode here. Or maybe we don't - openssl seems to
1400 # have identity issues in that area. 2012 # have identity issues in that area.
1401 Net::SSLeay::CTX_set_mode ($self->{tls}, 2013# Net::SSLeay::CTX_set_mode ($ssl,
1402 (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1) 2014# (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)
1403 | (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);
1404 2017
1405 $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); 2018 $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1406 $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); 2019 $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1407 2020
2021 Net::SSLeay::BIO_write ($self->{_rbio}, $self->{rbuf});
2022 $self->{rbuf} = "";
2023
1408 Net::SSLeay::set_bio ($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};
1409 2028
1410 &_dotls; # need to trigger the initial handshake 2029 &_dotls; # need to trigger the initial handshake
1411 $self->start_read; # make sure we actually do read 2030 $self->start_read; # make sure we actually do read
1412} 2031}
1413 2032
1414=item $handle->stoptls 2033=item $handle->stoptls
1415 2034
1416Shuts down the SSL connection - this makes a proper EOF handshake by 2035Shuts down the SSL connection - this makes a proper EOF handshake by
1417sending a close notify to the other side, but since OpenSSL doesn't 2036sending a close notify to the other side, but since OpenSSL doesn't
1418support non-blocking shut downs, it is not possible to re-use the stream 2037support non-blocking shut downs, it is not guaranteed that you can re-use
1419afterwards. 2038the stream afterwards.
2039
2040This method may invoke callbacks (and therefore the handle might be
2041destroyed after it returns).
1420 2042
1421=cut 2043=cut
1422 2044
1423sub stoptls { 2045sub stoptls {
1424 my ($self) = @_; 2046 my ($self) = @_;
1425 2047
1426 if ($self->{tls}) { 2048 if ($self->{tls} && $self->{fh}) {
1427 Net::SSLeay::shutdown ($self->{tls}); 2049 Net::SSLeay::shutdown ($self->{tls});
1428 2050
1429 &_dotls; 2051 &_dotls;
1430 2052
1431 # we don't give a shit. no, we do, but we can't. no... 2053# # we don't give a shit. no, we do, but we can't. no...#d#
1432 # we, we... have to use openssl :/ 2054# # we, we... have to use openssl :/#d#
1433 &_freetls; 2055# &_freetls;#d#
1434 } 2056 }
1435} 2057}
1436 2058
1437sub _freetls { 2059sub _freetls {
1438 my ($self) = @_; 2060 my ($self) = @_;
1439 2061
1440 return unless $self->{tls}; 2062 return unless $self->{tls};
1441 2063
1442 Net::SSLeay::free (delete $self->{tls}); 2064 $self->{tls_ctx}->_put_session (delete $self->{tls})
2065 if $self->{tls} > 0;
1443 2066
1444 delete @$self{qw(_rbio _wbio _tls_wbuf)}; 2067 delete @$self{qw(_rbio _wbio _tls_wbuf _on_starttls)};
1445} 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;
1446 2082
1447sub DESTROY { 2083sub DESTROY {
1448 my $self = shift; 2084 my ($self) = @_;
1449 2085
1450 &_freetls; 2086 &_freetls;
1451 2087
1452 my $linger = exists $self->{linger} ? $self->{linger} : 3600; 2088 my $linger = exists $self->{linger} ? $self->{linger} : 3600;
1453 2089
1454 if ($linger && length $self->{wbuf}) { 2090 if ($linger && length $self->{wbuf} && $self->{fh}) {
1455 my $fh = delete $self->{fh}; 2091 my $fh = delete $self->{fh};
1456 my $wbuf = delete $self->{wbuf}; 2092 my $wbuf = delete $self->{wbuf};
1457 2093
1458 my @linger; 2094 my @linger;
1459 2095
1460 push @linger, AnyEvent->io (fh => $fh, poll => "w", cb => sub { 2096 push @linger, AE::io $fh, 1, sub {
1461 my $len = syswrite $fh, $wbuf, length $wbuf; 2097 my $len = syswrite $fh, $wbuf, length $wbuf;
1462 2098
1463 if ($len > 0) { 2099 if ($len > 0) {
1464 substr $wbuf, 0, $len, ""; 2100 substr $wbuf, 0, $len, "";
1465 } else { 2101 } elsif (defined $len || ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK)) {
1466 @linger = (); # end 2102 @linger = (); # end
1467 } 2103 }
1468 }); 2104 };
1469 push @linger, AnyEvent->timer (after => $linger, cb => sub { 2105 push @linger, AE::timer $linger, 0, sub {
1470 @linger = (); 2106 @linger = ();
1471 }); 2107 };
1472 } 2108 }
1473} 2109}
1474 2110
1475=item $handle->destroy 2111=item $handle->destroy
1476 2112
1477Shut's down the handle object as much as possible - this call ensures that 2113Shuts down the handle object as much as possible - this call ensures that
1478no further callbacks will be invoked and resources will be freed as much 2114no further callbacks will be invoked and as many resources as possible
1479as possible. You must not call any methods on the object afterwards. 2115will be freed. Any method you will call on the handle object after
2116destroying it in this way will be silently ignored (and it will return the
2117empty list).
2118
2119Normally, you can just "forget" any references to an AnyEvent::Handle
2120object and it will simply shut down. This works in fatal error and EOF
2121callbacks, as well as code outside. It does I<NOT> work in a read or write
2122callback, so when you want to destroy the AnyEvent::Handle object from
2123within such an callback. You I<MUST> call C<< ->destroy >> explicitly in
2124that case.
2125
2126Destroying the handle object in this way has the advantage that callbacks
2127will be removed as well, so if those are the only reference holders (as
2128is common), then one doesn't need to do anything special to break any
2129reference cycles.
1480 2130
1481The handle might still linger in the background and write out remaining 2131The handle might still linger in the background and write out remaining
1482data, as specified by the C<linger> option, however. 2132data, as specified by the C<linger> option, however.
1483 2133
1484=cut 2134=cut
1486sub destroy { 2136sub destroy {
1487 my ($self) = @_; 2137 my ($self) = @_;
1488 2138
1489 $self->DESTROY; 2139 $self->DESTROY;
1490 %$self = (); 2140 %$self = ();
2141 bless $self, "AnyEvent::Handle::destroyed";
1491} 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 }
1492 2170
1493=item AnyEvent::Handle::TLS_CTX 2171=item AnyEvent::Handle::TLS_CTX
1494 2172
1495This function creates and returns the Net::SSLeay::CTX object used by 2173This function creates and returns the AnyEvent::TLS object used by default
1496default for TLS mode. 2174for TLS mode.
1497 2175
1498The context is created like this: 2176The context is created by calling L<AnyEvent::TLS> without any arguments.
1499
1500 Net::SSLeay::load_error_strings;
1501 Net::SSLeay::SSLeay_add_ssl_algorithms;
1502 Net::SSLeay::randomize;
1503
1504 my $CTX = Net::SSLeay::CTX_new;
1505
1506 Net::SSLeay::CTX_set_options $CTX, Net::SSLeay::OP_ALL
1507 2177
1508=cut 2178=cut
1509 2179
1510our $TLS_CTX; 2180our $TLS_CTX;
1511 2181
1512sub TLS_CTX() { 2182sub TLS_CTX() {
1513 $TLS_CTX || do { 2183 $TLS_CTX ||= do {
1514 require Net::SSLeay; 2184 require AnyEvent::TLS;
1515 2185
1516 Net::SSLeay::load_error_strings (); 2186 new AnyEvent::TLS
1517 Net::SSLeay::SSLeay_add_ssl_algorithms ();
1518 Net::SSLeay::randomize ();
1519
1520 $TLS_CTX = Net::SSLeay::CTX_new ();
1521
1522 Net::SSLeay::CTX_set_options ($TLS_CTX, Net::SSLeay::OP_ALL ());
1523
1524 $TLS_CTX
1525 } 2187 }
1526} 2188}
1527 2189
1528=back 2190=back
1529 2191
1530 2192
1531=head1 NONFREQUENTLY ASKED QUESTIONS 2193=head1 NONFREQUENTLY ASKED QUESTIONS
1532 2194
1533=over 4 2195=over 4
2196
2197=item I C<undef> the AnyEvent::Handle reference inside my callback and
2198still get further invocations!
2199
2200That's because AnyEvent::Handle keeps a reference to itself when handling
2201read or write callbacks.
2202
2203It is only safe to "forget" the reference inside EOF or error callbacks,
2204from within all other callbacks, you need to explicitly call the C<<
2205->destroy >> method.
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
2287=item I get different callback invocations in TLS mode/Why can't I pause
2288reading?
2289
2290Unlike, say, TCP, TLS connections do not consist of two independent
2291communication channels, one for each direction. Or put differently, the
2292read and write directions are not independent of each other: you cannot
2293write data unless you are also prepared to read, and vice versa.
2294
2295This means that, in TLS mode, you might get C<on_error> or C<on_eof>
2296callback invocations when you are not expecting any read data - the reason
2297is that AnyEvent::Handle always reads in TLS mode.
2298
2299During the connection, you have to make sure that you always have a
2300non-empty read-queue, or an C<on_read> watcher. At the end of the
2301connection (or when you no longer want to use it) you can call the
2302C<destroy> method.
1534 2303
1535=item How do I read data until the other side closes the connection? 2304=item How do I read data until the other side closes the connection?
1536 2305
1537If you just want to read your data into a perl scalar, the easiest way 2306If you just want to read your data into a perl scalar, the easiest way
1538to achieve this is by setting an C<on_read> callback that does nothing, 2307to achieve this is by setting an C<on_read> callback that does nothing,
1541 2310
1542 $handle->on_read (sub { }); 2311 $handle->on_read (sub { });
1543 $handle->on_eof (undef); 2312 $handle->on_eof (undef);
1544 $handle->on_error (sub { 2313 $handle->on_error (sub {
1545 my $data = delete $_[0]{rbuf}; 2314 my $data = delete $_[0]{rbuf};
1546 undef $handle;
1547 }); 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.
1548 2320
1549The 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
1550and 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
1551fact, all data has been received. 2323fact all data has been received.
1552 2324
1553It is usually better to use acknowledgements when transfering data, 2325It is usually better to use acknowledgements when transferring data,
1554to 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
1555intact. 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
1556explicit QUIT command. 2328explicit QUIT command.
1557
1558 2329
1559=item I don't want to destroy the handle too early - how do I wait until 2330=item I don't want to destroy the handle too early - how do I wait until
1560all data has been written? 2331all data has been written?
1561 2332
1562After writing your last bits of data, set the C<on_drain> callback 2333After writing your last bits of data, set the C<on_drain> callback
1564C<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
1565written to the socket: 2336written to the socket:
1566 2337
1567 $handle->push_write (...); 2338 $handle->push_write (...);
1568 $handle->on_drain (sub { 2339 $handle->on_drain (sub {
1569 warn "all data submitted to the kernel\n"; 2340 AE::log debug => "All data submitted to the kernel.";
1570 undef $handle; 2341 undef $handle;
1571 }); 2342 });
1572 2343
1573=item I get different callback invocations in TLS mode/Why can't I pause 2344If you just want to queue some data and then signal EOF to the other side,
1574reading? 2345consider using C<< ->push_shutdown >> instead.
1575 2346
1576Unlike, say, TCP, TLS conenctions do not consist of two independent 2347=item I want to contact a TLS/SSL server, I don't care about security.
1577communication channels, one for each direction. Or put differently. the
1578read and write directions are not independent of each other: you cannot
1579write data unless you are also prepared to read, and vice versa.
1580 2348
1581This can mean than, in TLS mode, you might get C<on_error> or C<on_eof> 2349If your TLS server is a pure TLS server (e.g. HTTPS) that only speaks TLS,
1582callback invocations when you are not expecting any read data - the reason 2350connect to it and then create the AnyEvent::Handle with the C<tls>
1583is that AnyEvent::Handle always reads in TLS mode. 2351parameter:
1584 2352
1585During the connection, you have to make sure that you always have a 2353 tcp_connect $host, $port, sub {
1586non-empty read-queue, or an C<on_read> watcher. At the end of the 2354 my ($fh) = @_;
1587connection (or when you no longer want to use it) you can call the 2355
1588C<destroy> method. 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>.
1589 2431
1590=back 2432=back
1591
1592 2433
1593=head1 SUBCLASSING AnyEvent::Handle 2434=head1 SUBCLASSING AnyEvent::Handle
1594 2435
1595In many cases, you might want to subclass AnyEvent::Handle. 2436In many cases, you might want to subclass AnyEvent::Handle.
1596 2437
1613 2454
1614=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
1615are free to use in subclasses. 2456are free to use in subclasses.
1616 2457
1617Of course, new versions of AnyEvent::Handle may introduce more "public" 2458Of course, new versions of AnyEvent::Handle may introduce more "public"
1618member variables, but thats just life, at least it is documented. 2459member variables, but that's just life. At least it is documented.
1619 2460
1620=back 2461=back
1621 2462
1622=head1 AUTHOR 2463=head1 AUTHOR
1623 2464
1624Robin 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>.
1625 2466
1626=cut 2467=cut
1627 2468
16281; # End of AnyEvent::Handle 24691
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