ViewVC Help
View File | Revision Log | Show Annotations | Download File
/cvs/AnyEvent/lib/AnyEvent/Handle.pm
(Generate patch)

Comparing AnyEvent/lib/AnyEvent/Handle.pm (file contents):
Revision 1.132 by elmex, Thu Jul 2 22:25:13 2009 UTC vs.
Revision 1.236 by root, Sat May 12 23:14:29 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 = 4.45;
20 4
21=head1 SYNOPSIS 5=head1 SYNOPSIS
22 6
23 use AnyEvent; 7 use AnyEvent;
24 use AnyEvent::Handle; 8 use AnyEvent::Handle;
25 9
26 my $cv = AnyEvent->condvar; 10 my $cv = AnyEvent->condvar;
27 11
28 my $handle = 12 my $hdl; $hdl = new AnyEvent::Handle
29 AnyEvent::Handle->new (
30 fh => \*STDIN, 13 fh => \*STDIN,
31 on_eof => sub { 14 on_error => sub {
15 my ($hdl, $fatal, $msg) = @_;
16 AE::log error => $msg;
17 $hdl->destroy;
32 $cv->send; 18 $cv->send;
33 },
34 ); 19 };
35 20
36 # send some request line 21 # send some request line
37 $handle->push_write ("getinfo\015\012"); 22 $hdl->push_write ("getinfo\015\012");
38 23
39 # read the response line 24 # read the response line
40 $handle->push_read (line => sub { 25 $hdl->push_read (line => sub {
41 my ($handle, $line) = @_; 26 my ($hdl, $line) = @_;
42 warn "read line <$line>\n"; 27 say "got line <$line>";
43 $cv->send; 28 $cv->send;
44 }); 29 });
45 30
46 $cv->recv; 31 $cv->recv;
47 32
48=head1 DESCRIPTION 33=head1 DESCRIPTION
49 34
50This module is a helper module to make it easier to do event-based I/O on 35This is a helper module to make it easier to do event-based I/O on
51filehandles. For utility functions for doing non-blocking connects and accepts 36stream-based filehandles (sockets, pipes, and other stream things).
52on sockets see L<AnyEvent::Util>.
53 37
54The L<AnyEvent::Intro> tutorial contains some well-documented 38The L<AnyEvent::Intro> tutorial contains some well-documented
55AnyEvent::Handle examples. 39AnyEvent::Handle examples.
56 40
57In the following, when the documentation refers to of "bytes" then this 41In the following, where the documentation refers to "bytes", it means
58means characters. As sysread and syswrite are used for all I/O, their 42characters. As sysread and syswrite are used for all I/O, their
59treatment of characters applies to this module as well. 43treatment of characters applies to this module as well.
44
45At the very minimum, you should specify C<fh> or C<connect>, and the
46C<on_error> callback.
60 47
61All callbacks will be invoked with the handle object as their first 48All callbacks will be invoked with the handle object as their first
62argument. 49argument.
63 50
51=cut
52
53package AnyEvent::Handle;
54
55use Scalar::Util ();
56use List::Util ();
57use Carp ();
58use Errno qw(EAGAIN EINTR);
59
60use AnyEvent (); BEGIN { AnyEvent::common_sense }
61use AnyEvent::Util qw(WSAEWOULDBLOCK);
62
63our $VERSION = $AnyEvent::VERSION;
64
65sub _load_func($) {
66 my $func = $_[0];
67
68 unless (defined &$func) {
69 my $pkg = $func;
70 do {
71 $pkg =~ s/::[^:]+$//
72 or return;
73 eval "require $pkg";
74 } until defined &$func;
75 }
76
77 \&$func
78}
79
80sub MAX_READ_SIZE() { 131072 }
81
64=head1 METHODS 82=head1 METHODS
65 83
66=over 4 84=over 4
67 85
68=item $handle = B<new> AnyEvent::TLS fh => $filehandle, key => value... 86=item $handle = B<new> AnyEvent::Handle fh => $filehandle, key => value...
69 87
70The constructor supports these arguments (all as C<< key => value >> pairs). 88The constructor supports these arguments (all as C<< key => value >> pairs).
71 89
72=over 4 90=over 4
73 91
74=item fh => $filehandle [MANDATORY] 92=item fh => $filehandle [C<fh> or C<connect> MANDATORY]
75 93
76The filehandle this L<AnyEvent::Handle> object will operate on. 94The filehandle this L<AnyEvent::Handle> object will operate on.
77
78NOTE: The filehandle will be set to non-blocking mode (using 95NOTE: The filehandle will be set to non-blocking mode (using
79C<AnyEvent::Util::fh_nonblocking>) by the constructor and needs to stay in 96C<AnyEvent::Util::fh_nonblocking>) by the constructor and needs to stay in
80that mode. 97that mode.
81 98
99=item connect => [$host, $service] [C<fh> or C<connect> MANDATORY]
100
101Try to connect to the specified host and service (port), using
102C<AnyEvent::Socket::tcp_connect>. The C<$host> additionally becomes the
103default C<peername>.
104
105You have to specify either this parameter, or C<fh>, above.
106
107It is possible to push requests on the read and write queues, and modify
108properties of the stream, even while AnyEvent::Handle is connecting.
109
110When this parameter is specified, then the C<on_prepare>,
111C<on_connect_error> and C<on_connect> callbacks will be called under the
112appropriate circumstances:
113
114=over 4
115
116=item on_prepare => $cb->($handle)
117
118This (rarely used) callback is called before a new connection is
119attempted, but after the file handle has been created (you can access that
120file handle via C<< $handle->{fh} >>). It could be used to prepare the
121file handle with parameters required for the actual connect (as opposed to
122settings that can be changed when the connection is already established).
123
124The return value of this callback should be the connect timeout value in
125seconds (or C<0>, or C<undef>, or the empty list, to indicate that the
126default timeout is to be used).
127
128=item on_connect => $cb->($handle, $host, $port, $retry->())
129
130This callback is called when a connection has been successfully established.
131
132The peer's numeric host and port (the socket peername) are passed as
133parameters, together with a retry callback. At the time it is called the
134read and write queues, EOF status, TLS status and similar properties of
135the handle will have been reset.
136
137It is not allowed to use the read or write queues while the handle object
138is connecting.
139
140If, for some reason, the handle is not acceptable, calling C<$retry> will
141continue with the next connection target (in case of multi-homed hosts or
142SRV records there can be multiple connection endpoints). The C<$retry>
143callback can be invoked after the connect callback returns, i.e. one can
144start a handshake and then decide to retry with the next host if the
145handshake fails.
146
147In most cases, you should ignore the C<$retry> parameter.
148
149=item on_connect_error => $cb->($handle, $message)
150
151This callback is called when the connection could not be
152established. C<$!> will contain the relevant error code, and C<$message> a
153message describing it (usually the same as C<"$!">).
154
155If this callback isn't specified, then C<on_error> will be called with a
156fatal error instead.
157
158=back
159
160=item on_error => $cb->($handle, $fatal, $message)
161
162This is the error callback, which is called when, well, some error
163occured, such as not being able to resolve the hostname, failure to
164connect, or a read error.
165
166Some errors are fatal (which is indicated by C<$fatal> being true). On
167fatal errors the handle object will be destroyed (by a call to C<< ->
168destroy >>) after invoking the error callback (which means you are free to
169examine the handle object). Examples of fatal errors are an EOF condition
170with active (but unsatisfiable) read watchers (C<EPIPE>) or I/O errors. In
171cases where the other side can close the connection at will, it is
172often easiest to not report C<EPIPE> errors in this callback.
173
174AnyEvent::Handle tries to find an appropriate error code for you to check
175against, but in some cases (TLS errors), this does not work well.
176
177If you report the error to the user, it is recommended to always output
178the C<$message> argument in human-readable error messages (you don't need
179to report C<"$!"> if you report C<$message>).
180
181If you want to react programmatically to the error, then looking at C<$!>
182and comparing it against some of the documented C<Errno> values is usually
183better than looking at the C<$message>.
184
185Non-fatal errors can be retried by returning, but it is recommended
186to simply ignore this parameter and instead abondon the handle object
187when this callback is invoked. Examples of non-fatal errors are timeouts
188C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>).
189
190On entry to the callback, the value of C<$!> contains the operating
191system error code (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT>, C<EBADMSG> or
192C<EPROTO>).
193
194While not mandatory, it is I<highly> recommended to set this callback, as
195you will not be notified of errors otherwise. The default just calls
196C<croak>.
197
198=item on_read => $cb->($handle)
199
200This sets the default read callback, which is called when data arrives
201and no read request is in the queue (unlike read queue callbacks, this
202callback will only be called when at least one octet of data is in the
203read buffer).
204
205To access (and remove data from) the read buffer, use the C<< ->rbuf >>
206method or access the C<< $handle->{rbuf} >> member directly. Note that you
207must not enlarge or modify the read buffer, you can only remove data at
208the beginning from it.
209
210You can also call C<< ->push_read (...) >> or any other function that
211modifies the read queue. Or do both. Or ...
212
213When an EOF condition is detected, AnyEvent::Handle will first try to
214feed all the remaining data to the queued callbacks and C<on_read> before
215calling the C<on_eof> callback. If no progress can be made, then a fatal
216error will be raised (with C<$!> set to C<EPIPE>).
217
218Note that, unlike requests in the read queue, an C<on_read> callback
219doesn't mean you I<require> some data: if there is an EOF and there
220are outstanding read requests then an error will be flagged. With an
221C<on_read> callback, the C<on_eof> callback will be invoked.
222
82=item on_eof => $cb->($handle) 223=item on_eof => $cb->($handle)
83 224
84Set the callback to be called when an end-of-file condition is detected, 225Set the callback to be called when an end-of-file condition is detected,
85i.e. in the case of a socket, when the other side has closed the 226i.e. in the case of a socket, when the other side has closed the
86connection cleanly. 227connection cleanly, and there are no outstanding read requests in the
228queue (if there are read requests, then an EOF counts as an unexpected
229connection close and will be flagged as an error).
87 230
88For sockets, this just means that the other side has stopped sending data, 231For sockets, this just means that the other side has stopped sending data,
89you can still try to write data, and, in fact, one can return from the EOF 232you can still try to write data, and, in fact, one can return from the EOF
90callback and continue writing data, as only the read part has been shut 233callback and continue writing data, as only the read part has been shut
91down. 234down.
92 235
93While not mandatory, it is I<highly> recommended to set an EOF callback,
94otherwise you might end up with a closed socket while you are still
95waiting for data.
96
97If an EOF condition has been detected but no C<on_eof> callback has been 236If an EOF condition has been detected but no C<on_eof> callback has been
98set, then a fatal error will be raised with C<$!> set to <0>. 237set, then a fatal error will be raised with C<$!> set to <0>.
99 238
100=item on_error => $cb->($handle, $fatal)
101
102This is the error callback, which is called when, well, some error
103occured, such as not being able to resolve the hostname, failure to
104connect or a read error.
105
106Some errors are fatal (which is indicated by C<$fatal> being true). On
107fatal errors the handle object will be shut down and will not be usable
108(but you are free to look at the current C<< ->rbuf >>). Examples of fatal
109errors are an EOF condition with active (but unsatisifable) read watchers
110(C<EPIPE>) or I/O errors.
111
112Non-fatal errors can be retried by simply returning, but it is recommended
113to simply ignore this parameter and instead abondon the handle object
114when this callback is invoked. Examples of non-fatal errors are timeouts
115C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>).
116
117On callback entrance, the value of C<$!> contains the operating system
118error (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT> or C<EBADMSG>).
119
120While not mandatory, it is I<highly> recommended to set this callback, as
121you will not be notified of errors otherwise. The default simply calls
122C<croak>.
123
124=item on_read => $cb->($handle)
125
126This sets the default read callback, which is called when data arrives
127and no read request is in the queue (unlike read queue callbacks, this
128callback will only be called when at least one octet of data is in the
129read buffer).
130
131To access (and remove data from) the read buffer, use the C<< ->rbuf >>
132method or access the C<$handle->{rbuf}> member directly. Note that you
133must not enlarge or modify the read buffer, you can only remove data at
134the beginning from it.
135
136When an EOF condition is detected then AnyEvent::Handle will first try to
137feed all the remaining data to the queued callbacks and C<on_read> before
138calling the C<on_eof> callback. If no progress can be made, then a fatal
139error will be raised (with C<$!> set to C<EPIPE>).
140
141=item on_drain => $cb->($handle) 239=item on_drain => $cb->($handle)
142 240
143This sets the callback that is called when the write buffer becomes empty 241This sets the callback that is called once when the write buffer becomes
144(or when the callback is set and the buffer is empty already). 242empty (and immediately when the handle object is created).
145 243
146To append to the write buffer, use the C<< ->push_write >> method. 244To append to the write buffer, use the C<< ->push_write >> method.
147 245
148This callback is useful when you don't want to put all of your write data 246This callback is useful when you don't want to put all of your write data
149into the queue at once, for example, when you want to write the contents 247into the queue at once, for example, when you want to write the contents
151memory and push it into the queue, but instead only read more data from 249memory and push it into the queue, but instead only read more data from
152the file when the write queue becomes empty. 250the file when the write queue becomes empty.
153 251
154=item timeout => $fractional_seconds 252=item timeout => $fractional_seconds
155 253
254=item rtimeout => $fractional_seconds
255
256=item wtimeout => $fractional_seconds
257
156If non-zero, then this enables an "inactivity" timeout: whenever this many 258If non-zero, then these enables an "inactivity" timeout: whenever this
157seconds pass without a successful read or write on the underlying file 259many seconds pass without a successful read or write on the underlying
158handle, the C<on_timeout> callback will be invoked (and if that one is 260file handle (or a call to C<timeout_reset>), the C<on_timeout> callback
159missing, a non-fatal C<ETIMEDOUT> error will be raised). 261will be invoked (and if that one is missing, a non-fatal C<ETIMEDOUT>
262error will be raised).
160 263
264There are three variants of the timeouts that work independently of each
265other, for both read and write (triggered when nothing was read I<OR>
266written), just read (triggered when nothing was read), and just write:
267C<timeout>, C<rtimeout> and C<wtimeout>, with corresponding callbacks
268C<on_timeout>, C<on_rtimeout> and C<on_wtimeout>, and reset functions
269C<timeout_reset>, C<rtimeout_reset>, and C<wtimeout_reset>.
270
161Note that timeout processing is also active when you currently do not have 271Note that timeout processing is active even when you do not have any
162any outstanding read or write requests: If you plan to keep the connection 272outstanding read or write requests: If you plan to keep the connection
163idle then you should disable the timout temporarily or ignore the timeout 273idle then you should disable the timeout temporarily or ignore the
164in the C<on_timeout> callback, in which case AnyEvent::Handle will simply 274timeout in the corresponding C<on_timeout> callback, in which case
165restart the timeout. 275AnyEvent::Handle will simply restart the timeout.
166 276
167Zero (the default) disables this timeout. 277Zero (the default) disables the corresponding timeout.
168 278
169=item on_timeout => $cb->($handle) 279=item on_timeout => $cb->($handle)
280
281=item on_rtimeout => $cb->($handle)
282
283=item on_wtimeout => $cb->($handle)
170 284
171Called whenever the inactivity timeout passes. If you return from this 285Called whenever the inactivity timeout passes. If you return from this
172callback, then the timeout will be reset as if some activity had happened, 286callback, then the timeout will be reset as if some activity had happened,
173so this condition is not fatal in any way. 287so this condition is not fatal in any way.
174 288
182be configured to accept only so-and-so much data that it cannot act on 296be configured to accept only so-and-so much data that it cannot act on
183(for example, when expecting a line, an attacker could send an unlimited 297(for example, when expecting a line, an attacker could send an unlimited
184amount of data without a callback ever being called as long as the line 298amount of data without a callback ever being called as long as the line
185isn't finished). 299isn't finished).
186 300
301=item wbuf_max => <bytes>
302
303If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)
304when the write buffer ever (strictly) exceeds this size. This is useful to
305avoid some forms of denial-of-service attacks.
306
307Although the units of this parameter is bytes, this is the I<raw> number
308of bytes not yet accepted by the kernel. This can make a difference when
309you e.g. use TLS, as TLS typically makes your write data larger (but it
310can also make it smaller due to compression).
311
312As an example of when this limit is useful, take a chat server that sends
313chat messages to a client. If the client does not read those in a timely
314manner then the send buffer in the server would grow unbounded.
315
187=item autocork => <boolean> 316=item autocork => <boolean>
188 317
189When disabled (the default), then C<push_write> will try to immediately 318When disabled (the default), C<push_write> will try to immediately
190write the data to the handle, if possible. This avoids having to register 319write the data to the handle if possible. This avoids having to register
191a write watcher and wait for the next event loop iteration, but can 320a write watcher and wait for the next event loop iteration, but can
192be inefficient if you write multiple small chunks (on the wire, this 321be inefficient if you write multiple small chunks (on the wire, this
193disadvantage is usually avoided by your kernel's nagle algorithm, see 322disadvantage is usually avoided by your kernel's nagle algorithm, see
194C<no_delay>, but this option can save costly syscalls). 323C<no_delay>, but this option can save costly syscalls).
195 324
196When enabled, then writes will always be queued till the next event loop 325When enabled, writes will always be queued till the next event loop
197iteration. This is efficient when you do many small writes per iteration, 326iteration. This is efficient when you do many small writes per iteration,
198but less efficient when you do a single write only per iteration (or when 327but less efficient when you do a single write only per iteration (or when
199the write buffer often is full). It also increases write latency. 328the write buffer often is full). It also increases write latency.
200 329
201=item no_delay => <boolean> 330=item no_delay => <boolean>
205the Nagle algorithm, and usually it is beneficial. 334the Nagle algorithm, and usually it is beneficial.
206 335
207In some situations you want as low a delay as possible, which can be 336In some situations you want as low a delay as possible, which can be
208accomplishd by setting this option to a true value. 337accomplishd by setting this option to a true value.
209 338
210The default is your opertaing system's default behaviour (most likely 339The default is your operating system's default behaviour (most likely
211enabled), this option explicitly enables or disables it, if possible. 340enabled). This option explicitly enables or disables it, if possible.
341
342=item keepalive => <boolean>
343
344Enables (default disable) the SO_KEEPALIVE option on the stream socket:
345normally, TCP connections have no time-out once established, so TCP
346connections, once established, can stay alive forever even when the other
347side has long gone. TCP keepalives are a cheap way to take down long-lived
348TCP connections when the other side becomes unreachable. While the default
349is OS-dependent, TCP keepalives usually kick in after around two hours,
350and, if the other side doesn't reply, take down the TCP connection some 10
351to 15 minutes later.
352
353It is harmless to specify this option for file handles that do not support
354keepalives, and enabling it on connections that are potentially long-lived
355is usually a good idea.
356
357=item oobinline => <boolean>
358
359BSD majorly fucked up the implementation of TCP urgent data. The result
360is that almost no OS implements TCP according to the specs, and every OS
361implements it slightly differently.
362
363If you want to handle TCP urgent data, then setting this flag (the default
364is enabled) gives you the most portable way of getting urgent data, by
365putting it into the stream.
366
367Since BSD emulation of OOB data on top of TCP's urgent data can have
368security implications, AnyEvent::Handle sets this flag automatically
369unless explicitly specified. Note that setting this flag after
370establishing a connection I<may> be a bit too late (data loss could
371already have occured on BSD systems), but at least it will protect you
372from most attacks.
212 373
213=item read_size => <bytes> 374=item read_size => <bytes>
214 375
215The default read block size (the amount of bytes this module will 376The initial read block size, the number of bytes this module will try
216try to read during each loop iteration, which affects memory 377to read during each loop iteration. Each handle object will consume
217requirements). Default: C<8192>. 378at least this amount of memory for the read buffer as well, so when
379handling many connections watch out for memory requirements). See also
380C<max_read_size>. Default: C<2048>.
381
382=item max_read_size => <bytes>
383
384The maximum read buffer size used by the dynamic adjustment
385algorithm: Each time AnyEvent::Handle can read C<read_size> bytes in
386one go it will double C<read_size> up to the maximum given by this
387option. Default: C<131072> or C<read_size>, whichever is higher.
218 388
219=item low_water_mark => <bytes> 389=item low_water_mark => <bytes>
220 390
221Sets the amount of bytes (default: C<0>) that make up an "empty" write 391Sets the number of bytes (default: C<0>) that make up an "empty" write
222buffer: If the write reaches this size or gets even samller it is 392buffer: If the buffer reaches this size or gets even samller it is
223considered empty. 393considered empty.
224 394
225Sometimes it can be beneficial (for performance reasons) to add data to 395Sometimes it can be beneficial (for performance reasons) to add data to
226the write buffer before it is fully drained, but this is a rare case, as 396the write buffer before it is fully drained, but this is a rare case, as
227the operating system kernel usually buffers data as well, so the default 397the operating system kernel usually buffers data as well, so the default
228is good in almost all cases. 398is good in almost all cases.
229 399
230=item linger => <seconds> 400=item linger => <seconds>
231 401
232If non-zero (default: C<3600>), then the destructor of the 402If this is non-zero (default: C<3600>), the destructor of the
233AnyEvent::Handle object will check whether there is still outstanding 403AnyEvent::Handle object will check whether there is still outstanding
234write data and will install a watcher that will write this data to the 404write data and will install a watcher that will write this data to the
235socket. No errors will be reported (this mostly matches how the operating 405socket. No errors will be reported (this mostly matches how the operating
236system treats outstanding data at socket close time). 406system treats outstanding data at socket close time).
237 407
238This will not work for partial TLS data that could not be encoded 408This will not work for partial TLS data that could not be encoded
239yet. This data will be lost. Calling the C<stoptls> method in time might 409yet. This data will be lost. Calling the C<stoptls> method in time might
240help. 410help.
241 411
242=item common_name => $string 412=item peername => $string
243 413
244The common name used by some verification methods (most notably SSL/TLS) 414A string used to identify the remote site - usually the DNS hostname
245associated with this connection. Usually this is the remote hostname used 415(I<not> IDN!) used to create the connection, rarely the IP address.
246to connect, but can be almost anything. 416
417Apart from being useful in error messages, this string is also used in TLS
418peername verification (see C<verify_peername> in L<AnyEvent::TLS>). This
419verification will be skipped when C<peername> is not specified or is
420C<undef>.
247 421
248=item tls => "accept" | "connect" | Net::SSLeay::SSL object 422=item tls => "accept" | "connect" | Net::SSLeay::SSL object
249 423
250When this parameter is given, it enables TLS (SSL) mode, that means 424When this parameter is given, it enables TLS (SSL) mode, that means
251AnyEvent will start a TLS handshake as soon as the conenction has been 425AnyEvent will start a TLS handshake as soon as the connection has been
252established and will transparently encrypt/decrypt data afterwards. 426established and will transparently encrypt/decrypt data afterwards.
427
428All TLS protocol errors will be signalled as C<EPROTO>, with an
429appropriate error message.
253 430
254TLS mode requires Net::SSLeay to be installed (it will be loaded 431TLS mode requires Net::SSLeay to be installed (it will be loaded
255automatically when you try to create a TLS handle): this module doesn't 432automatically when you try to create a TLS handle): this module doesn't
256have a dependency on that module, so if your module requires it, you have 433have a dependency on that module, so if your module requires it, you have
257to add the dependency yourself. 434to add the dependency yourself. If Net::SSLeay cannot be loaded or is too
435old, you get an C<EPROTO> error.
258 436
259Unlike TCP, TLS has a server and client side: for the TLS server side, use 437Unlike TCP, TLS has a server and client side: for the TLS server side, use
260C<accept>, and for the TLS client side of a connection, use C<connect> 438C<accept>, and for the TLS client side of a connection, use C<connect>
261mode. 439mode.
262 440
273B<IMPORTANT:> since Net::SSLeay "objects" are really only integers, 451B<IMPORTANT:> since Net::SSLeay "objects" are really only integers,
274passing in the wrong integer will lead to certain crash. This most often 452passing in the wrong integer will lead to certain crash. This most often
275happens when one uses a stylish C<< tls => 1 >> and is surprised about the 453happens when one uses a stylish C<< tls => 1 >> and is surprised about the
276segmentation fault. 454segmentation fault.
277 455
278See the C<< ->starttls >> method for when need to start TLS negotiation later. 456Use the C<< ->starttls >> method if you need to start TLS negotiation later.
279 457
280=item tls_ctx => $anyevent_tls 458=item tls_ctx => $anyevent_tls
281 459
282Use the given C<AnyEvent::TLS> object to create the new TLS connection 460Use the given C<AnyEvent::TLS> object to create the new TLS connection
283(unless a connection object was specified directly). If this parameter is 461(unless a connection object was specified directly). If this
284missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>. 462parameter is missing (or C<undef>), then AnyEvent::Handle will use
463C<AnyEvent::Handle::TLS_CTX>.
285 464
286Instead of an object, you can also specify a hash reference with C<< key 465Instead of an object, you can also specify a hash reference with C<< key
287=> value >> pairs. Those will be passed to L<AnyEvent::TLS> to create a 466=> value >> pairs. Those will be passed to L<AnyEvent::TLS> to create a
288new TLS context object. 467new TLS context object.
289 468
469=item on_starttls => $cb->($handle, $success[, $error_message])
470
471This callback will be invoked when the TLS/SSL handshake has finished. If
472C<$success> is true, then the TLS handshake succeeded, otherwise it failed
473(C<on_stoptls> will not be called in this case).
474
475The session in C<< $handle->{tls} >> can still be examined in this
476callback, even when the handshake was not successful.
477
478TLS handshake failures will not cause C<on_error> to be invoked when this
479callback is in effect, instead, the error message will be passed to C<on_starttls>.
480
481Without this callback, handshake failures lead to C<on_error> being
482called as usual.
483
484Note that you cannot just call C<starttls> again in this callback. If you
485need to do that, start an zero-second timer instead whose callback can
486then call C<< ->starttls >> again.
487
488=item on_stoptls => $cb->($handle)
489
490When a SSLv3/TLS shutdown/close notify/EOF is detected and this callback is
491set, then it will be invoked after freeing the TLS session. If it is not,
492then a TLS shutdown condition will be treated like a normal EOF condition
493on the handle.
494
495The session in C<< $handle->{tls} >> can still be examined in this
496callback.
497
498This callback will only be called on TLS shutdowns, not when the
499underlying handle signals EOF.
500
290=item json => JSON or JSON::XS object 501=item json => JSON or JSON::XS object
291 502
292This is the json coder object used by the C<json> read and write types. 503This is the json coder object used by the C<json> read and write types.
293 504
294If you don't supply it, then AnyEvent::Handle will create and use a 505If you don't supply it, then AnyEvent::Handle will create and use a
304 515
305sub new { 516sub new {
306 my $class = shift; 517 my $class = shift;
307 my $self = bless { @_ }, $class; 518 my $self = bless { @_ }, $class;
308 519
309 $self->{fh} or Carp::croak "mandatory argument fh is missing"; 520 if ($self->{fh}) {
521 $self->_start;
522 return unless $self->{fh}; # could be gone by now
523
524 } elsif ($self->{connect}) {
525 require AnyEvent::Socket;
526
527 $self->{peername} = $self->{connect}[0]
528 unless exists $self->{peername};
529
530 $self->{_skip_drain_rbuf} = 1;
531
532 {
533 Scalar::Util::weaken (my $self = $self);
534
535 $self->{_connect} =
536 AnyEvent::Socket::tcp_connect (
537 $self->{connect}[0],
538 $self->{connect}[1],
539 sub {
540 my ($fh, $host, $port, $retry) = @_;
541
542 delete $self->{_connect}; # no longer needed
543
544 if ($fh) {
545 $self->{fh} = $fh;
546
547 delete $self->{_skip_drain_rbuf};
548 $self->_start;
549
550 $self->{on_connect}
551 and $self->{on_connect}($self, $host, $port, sub {
552 delete @$self{qw(fh _tw _rtw _wtw _ww _rw _eof _queue rbuf _wbuf tls _tls_rbuf _tls_wbuf)};
553 $self->{_skip_drain_rbuf} = 1;
554 &$retry;
555 });
556
557 } else {
558 if ($self->{on_connect_error}) {
559 $self->{on_connect_error}($self, "$!");
560 $self->destroy if $self;
561 } else {
562 $self->_error ($!, 1);
563 }
564 }
565 },
566 sub {
567 local $self->{fh} = $_[0];
568
569 $self->{on_prepare}
570 ? $self->{on_prepare}->($self)
571 : ()
572 }
573 );
574 }
575
576 } else {
577 Carp::croak "AnyEvent::Handle: either an existing fh or the connect parameter must be specified";
578 }
579
580 $self
581}
582
583sub _start {
584 my ($self) = @_;
585
586 # too many clueless people try to use udp and similar sockets
587 # with AnyEvent::Handle, do them a favour.
588 my $type = getsockopt $self->{fh}, Socket::SOL_SOCKET (), Socket::SO_TYPE ();
589 Carp::croak "AnyEvent::Handle: only stream sockets supported, anything else will NOT work!"
590 if Socket::SOCK_STREAM () != (unpack "I", $type) && defined $type;
310 591
311 AnyEvent::Util::fh_nonblocking $self->{fh}, 1; 592 AnyEvent::Util::fh_nonblocking $self->{fh}, 1;
312 593
594 $self->{_activity} =
595 $self->{_ractivity} =
313 $self->{_activity} = AnyEvent->now; 596 $self->{_wactivity} = AE::now;
314 $self->_timeout;
315 597
598 $self->{read_size} ||= 2048;
599 $self->{max_read_size} = $self->{read_size}
600 if $self->{read_size} > ($self->{max_read_size} || MAX_READ_SIZE);
601
602 $self->timeout (delete $self->{timeout} ) if $self->{timeout};
603 $self->rtimeout (delete $self->{rtimeout} ) if $self->{rtimeout};
604 $self->wtimeout (delete $self->{wtimeout} ) if $self->{wtimeout};
605
316 $self->no_delay (delete $self->{no_delay}) if exists $self->{no_delay}; 606 $self->no_delay (delete $self->{no_delay} ) if exists $self->{no_delay} && $self->{no_delay};
607 $self->keepalive (delete $self->{keepalive}) if exists $self->{keepalive} && $self->{keepalive};
317 608
609 $self->oobinline (exists $self->{oobinline} ? delete $self->{oobinline} : 1);
610
318 $self->starttls (delete $self->{tls}, delete $self->{tls_ctx}) 611 $self->starttls (delete $self->{tls}, delete $self->{tls_ctx})
319 if $self->{tls}; 612 if $self->{tls};
320 613
321 $self->on_drain (delete $self->{on_drain}) if exists $self->{on_drain}; 614 $self->on_drain (delete $self->{on_drain} ) if $self->{on_drain};
322 615
323 $self->start_read 616 $self->start_read
324 if $self->{on_read}; 617 if $self->{on_read} || @{ $self->{_queue} };
325 618
326 $self->{fh} && $self 619 $self->_drain_wbuf;
327}
328
329sub _shutdown {
330 my ($self) = @_;
331
332 delete @$self{qw(_tw _rw _ww fh wbuf on_read _queue)};
333 $self->{_eof} = 1; # tell starttls et. al to stop trying
334
335 &_freetls;
336} 620}
337 621
338sub _error { 622sub _error {
339 my ($self, $errno, $fatal) = @_; 623 my ($self, $errno, $fatal, $message) = @_;
340
341 $self->_shutdown
342 if $fatal;
343 624
344 $! = $errno; 625 $! = $errno;
626 $message ||= "$!";
345 627
346 if ($self->{on_error}) { 628 if ($self->{on_error}) {
347 $self->{on_error}($self, $fatal); 629 $self->{on_error}($self, $fatal, $message);
348 } elsif ($self->{fh}) { 630 $self->destroy if $fatal;
631 } elsif ($self->{fh} || $self->{connect}) {
632 $self->destroy;
349 Carp::croak "AnyEvent::Handle uncaught error: $!"; 633 Carp::croak "AnyEvent::Handle uncaught error: $message";
350 } 634 }
351} 635}
352 636
353=item $fh = $handle->fh 637=item $fh = $handle->fh
354 638
378 $_[0]{on_eof} = $_[1]; 662 $_[0]{on_eof} = $_[1];
379} 663}
380 664
381=item $handle->on_timeout ($cb) 665=item $handle->on_timeout ($cb)
382 666
383Replace the current C<on_timeout> callback, or disables the callback (but 667=item $handle->on_rtimeout ($cb)
384not the timeout) if C<$cb> = C<undef>. See the C<timeout> constructor
385argument and method.
386 668
387=cut 669=item $handle->on_wtimeout ($cb)
388 670
389sub on_timeout { 671Replace the current C<on_timeout>, C<on_rtimeout> or C<on_wtimeout>
390 $_[0]{on_timeout} = $_[1]; 672callback, or disables the callback (but not the timeout) if C<$cb> =
391} 673C<undef>. See the C<timeout> constructor argument and method.
674
675=cut
676
677# see below
392 678
393=item $handle->autocork ($boolean) 679=item $handle->autocork ($boolean)
394 680
395Enables or disables the current autocork behaviour (see C<autocork> 681Enables or disables the current autocork behaviour (see C<autocork>
396constructor argument). Changes will only take effect on the next write. 682constructor argument). Changes will only take effect on the next write.
409=cut 695=cut
410 696
411sub no_delay { 697sub no_delay {
412 $_[0]{no_delay} = $_[1]; 698 $_[0]{no_delay} = $_[1];
413 699
700 setsockopt $_[0]{fh}, Socket::IPPROTO_TCP (), Socket::TCP_NODELAY (), int $_[1]
701 if $_[0]{fh};
702}
703
704=item $handle->keepalive ($boolean)
705
706Enables or disables the C<keepalive> setting (see constructor argument of
707the same name for details).
708
709=cut
710
711sub keepalive {
712 $_[0]{keepalive} = $_[1];
713
414 eval { 714 eval {
415 local $SIG{__DIE__}; 715 local $SIG{__DIE__};
416 setsockopt $_[0]{fh}, &Socket::IPPROTO_TCP, &Socket::TCP_NODELAY, int $_[1]; 716 setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_KEEPALIVE (), int $_[1]
717 if $_[0]{fh};
417 }; 718 };
418} 719}
419 720
721=item $handle->oobinline ($boolean)
722
723Enables or disables the C<oobinline> setting (see constructor argument of
724the same name for details).
725
726=cut
727
728sub oobinline {
729 $_[0]{oobinline} = $_[1];
730
731 eval {
732 local $SIG{__DIE__};
733 setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_OOBINLINE (), int $_[1]
734 if $_[0]{fh};
735 };
736}
737
738=item $handle->keepalive ($boolean)
739
740Enables or disables the C<keepalive> setting (see constructor argument of
741the same name for details).
742
743=cut
744
745sub keepalive {
746 $_[0]{keepalive} = $_[1];
747
748 eval {
749 local $SIG{__DIE__};
750 setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_KEEPALIVE (), int $_[1]
751 if $_[0]{fh};
752 };
753}
754
755=item $handle->on_starttls ($cb)
756
757Replace the current C<on_starttls> callback (see the C<on_starttls> constructor argument).
758
759=cut
760
761sub on_starttls {
762 $_[0]{on_starttls} = $_[1];
763}
764
765=item $handle->on_stoptls ($cb)
766
767Replace the current C<on_stoptls> callback (see the C<on_stoptls> constructor argument).
768
769=cut
770
771sub on_stoptls {
772 $_[0]{on_stoptls} = $_[1];
773}
774
775=item $handle->rbuf_max ($max_octets)
776
777Configures the C<rbuf_max> setting (C<undef> disables it).
778
779=item $handle->wbuf_max ($max_octets)
780
781Configures the C<wbuf_max> setting (C<undef> disables it).
782
783=cut
784
785sub rbuf_max {
786 $_[0]{rbuf_max} = $_[1];
787}
788
789sub wbuf_max {
790 $_[0]{wbuf_max} = $_[1];
791}
792
420############################################################################# 793#############################################################################
421 794
422=item $handle->timeout ($seconds) 795=item $handle->timeout ($seconds)
423 796
797=item $handle->rtimeout ($seconds)
798
799=item $handle->wtimeout ($seconds)
800
424Configures (or disables) the inactivity timeout. 801Configures (or disables) the inactivity timeout.
425 802
426=cut 803The timeout will be checked instantly, so this method might destroy the
804handle before it returns.
427 805
428sub timeout { 806=item $handle->timeout_reset
807
808=item $handle->rtimeout_reset
809
810=item $handle->wtimeout_reset
811
812Reset the activity timeout, as if data was received or sent.
813
814These methods are cheap to call.
815
816=cut
817
818for my $dir ("", "r", "w") {
819 my $timeout = "${dir}timeout";
820 my $tw = "_${dir}tw";
821 my $on_timeout = "on_${dir}timeout";
822 my $activity = "_${dir}activity";
823 my $cb;
824
825 *$on_timeout = sub {
826 $_[0]{$on_timeout} = $_[1];
827 };
828
829 *$timeout = sub {
429 my ($self, $timeout) = @_; 830 my ($self, $new_value) = @_;
430 831
832 $new_value >= 0
833 or Carp::croak "AnyEvent::Handle->$timeout called with negative timeout ($new_value), caught";
834
431 $self->{timeout} = $timeout; 835 $self->{$timeout} = $new_value;
432 $self->_timeout; 836 delete $self->{$tw}; &$cb;
433} 837 };
434 838
839 *{"${dir}timeout_reset"} = sub {
840 $_[0]{$activity} = AE::now;
841 };
842
843 # main workhorse:
435# reset the timeout watcher, as neccessary 844 # reset the timeout watcher, as neccessary
436# also check for time-outs 845 # also check for time-outs
437sub _timeout { 846 $cb = sub {
438 my ($self) = @_; 847 my ($self) = @_;
439 848
440 if ($self->{timeout}) { 849 if ($self->{$timeout} && $self->{fh}) {
441 my $NOW = AnyEvent->now; 850 my $NOW = AE::now;
442 851
443 # when would the timeout trigger? 852 # when would the timeout trigger?
444 my $after = $self->{_activity} + $self->{timeout} - $NOW; 853 my $after = $self->{$activity} + $self->{$timeout} - $NOW;
445 854
446 # now or in the past already? 855 # now or in the past already?
447 if ($after <= 0) { 856 if ($after <= 0) {
448 $self->{_activity} = $NOW; 857 $self->{$activity} = $NOW;
449 858
450 if ($self->{on_timeout}) { 859 if ($self->{$on_timeout}) {
451 $self->{on_timeout}($self); 860 $self->{$on_timeout}($self);
452 } else { 861 } else {
453 $self->_error (&Errno::ETIMEDOUT); 862 $self->_error (Errno::ETIMEDOUT);
863 }
864
865 # callback could have changed timeout value, optimise
866 return unless $self->{$timeout};
867
868 # calculate new after
869 $after = $self->{$timeout};
454 } 870 }
455 871
456 # callback could have changed timeout value, optimise 872 Scalar::Util::weaken $self;
457 return unless $self->{timeout}; 873 return unless $self; # ->error could have destroyed $self
458 874
459 # calculate new after 875 $self->{$tw} ||= AE::timer $after, 0, sub {
460 $after = $self->{timeout}; 876 delete $self->{$tw};
877 $cb->($self);
878 };
879 } else {
880 delete $self->{$tw};
461 } 881 }
462
463 Scalar::Util::weaken $self;
464 return unless $self; # ->error could have destroyed $self
465
466 $self->{_tw} ||= AnyEvent->timer (after => $after, cb => sub {
467 delete $self->{_tw};
468 $self->_timeout;
469 });
470 } else {
471 delete $self->{_tw};
472 } 882 }
473} 883}
474 884
475############################################################################# 885#############################################################################
476 886
483 893
484The write queue is very simple: you can add data to its end, and 894The write queue is very simple: you can add data to its end, and
485AnyEvent::Handle will automatically try to get rid of it for you. 895AnyEvent::Handle will automatically try to get rid of it for you.
486 896
487When data could be written and the write buffer is shorter then the low 897When data could be written and the write buffer is shorter then the low
488water mark, the C<on_drain> callback will be invoked. 898water mark, the C<on_drain> callback will be invoked once.
489 899
490=over 4 900=over 4
491 901
492=item $handle->on_drain ($cb) 902=item $handle->on_drain ($cb)
493 903
494Sets the C<on_drain> callback or clears it (see the description of 904Sets the C<on_drain> callback or clears it (see the description of
495C<on_drain> in the constructor). 905C<on_drain> in the constructor).
496 906
907This method may invoke callbacks (and therefore the handle might be
908destroyed after it returns).
909
497=cut 910=cut
498 911
499sub on_drain { 912sub on_drain {
500 my ($self, $cb) = @_; 913 my ($self, $cb) = @_;
501 914
505 if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf}); 918 if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf});
506} 919}
507 920
508=item $handle->push_write ($data) 921=item $handle->push_write ($data)
509 922
510Queues the given scalar to be written. You can push as much data as you 923Queues the given scalar to be written. You can push as much data as
511want (only limited by the available memory), as C<AnyEvent::Handle> 924you want (only limited by the available memory and C<wbuf_max>), as
512buffers it independently of the kernel. 925C<AnyEvent::Handle> buffers it independently of the kernel.
926
927This method may invoke callbacks (and therefore the handle might be
928destroyed after it returns).
513 929
514=cut 930=cut
515 931
516sub _drain_wbuf { 932sub _drain_wbuf {
517 my ($self) = @_; 933 my ($self) = @_;
521 Scalar::Util::weaken $self; 937 Scalar::Util::weaken $self;
522 938
523 my $cb = sub { 939 my $cb = sub {
524 my $len = syswrite $self->{fh}, $self->{wbuf}; 940 my $len = syswrite $self->{fh}, $self->{wbuf};
525 941
526 if ($len >= 0) { 942 if (defined $len) {
527 substr $self->{wbuf}, 0, $len, ""; 943 substr $self->{wbuf}, 0, $len, "";
528 944
529 $self->{_activity} = AnyEvent->now; 945 $self->{_activity} = $self->{_wactivity} = AE::now;
530 946
531 $self->{on_drain}($self) 947 $self->{on_drain}($self)
532 if $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf}) 948 if $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf})
533 && $self->{on_drain}; 949 && $self->{on_drain};
534 950
540 956
541 # try to write data immediately 957 # try to write data immediately
542 $cb->() unless $self->{autocork}; 958 $cb->() unless $self->{autocork};
543 959
544 # if still data left in wbuf, we need to poll 960 # if still data left in wbuf, we need to poll
545 $self->{_ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb) 961 $self->{_ww} = AE::io $self->{fh}, 1, $cb
546 if length $self->{wbuf}; 962 if length $self->{wbuf};
963
964 if (
965 defined $self->{wbuf_max}
966 && $self->{wbuf_max} < length $self->{wbuf}
967 ) {
968 $self->_error (Errno::ENOSPC, 1), return;
969 }
547 }; 970 };
548} 971}
549 972
550our %WH; 973our %WH;
551 974
975# deprecated
552sub register_write_type($$) { 976sub register_write_type($$) {
553 $WH{$_[0]} = $_[1]; 977 $WH{$_[0]} = $_[1];
554} 978}
555 979
556sub push_write { 980sub push_write {
557 my $self = shift; 981 my $self = shift;
558 982
559 if (@_ > 1) { 983 if (@_ > 1) {
560 my $type = shift; 984 my $type = shift;
561 985
986 @_ = ($WH{$type} ||= _load_func "$type\::anyevent_write_type"
562 @_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write") 987 or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::push_write")
563 ->($self, @_); 988 ->($self, @_);
564 } 989 }
565 990
991 # we downgrade here to avoid hard-to-track-down bugs,
992 # and diagnose the problem earlier and better.
993
566 if ($self->{tls}) { 994 if ($self->{tls}) {
567 $self->{_tls_wbuf} .= $_[0]; 995 utf8::downgrade $self->{_tls_wbuf} .= $_[0];
568 996 &_dotls ($self) if $self->{fh};
569 &_dotls ($self);
570 } else { 997 } else {
571 $self->{wbuf} .= $_[0]; 998 utf8::downgrade $self->{wbuf} .= $_[0];
572 $self->_drain_wbuf; 999 $self->_drain_wbuf if $self->{fh};
573 } 1000 }
574} 1001}
575 1002
576=item $handle->push_write (type => @args) 1003=item $handle->push_write (type => @args)
577 1004
578Instead of formatting your data yourself, you can also let this module do 1005Instead of formatting your data yourself, you can also let this module
579the job by specifying a type and type-specific arguments. 1006do the job by specifying a type and type-specific arguments. You
1007can also specify the (fully qualified) name of a package, in which
1008case AnyEvent tries to load the package and then expects to find the
1009C<anyevent_write_type> function inside (see "custom write types", below).
580 1010
581Predefined types are (if you have ideas for additional types, feel free to 1011Predefined types are (if you have ideas for additional types, feel free to
582drop by and tell us): 1012drop by and tell us):
583 1013
584=over 4 1014=over 4
641Other languages could read single lines terminated by a newline and pass 1071Other languages could read single lines terminated by a newline and pass
642this line into their JSON decoder of choice. 1072this line into their JSON decoder of choice.
643 1073
644=cut 1074=cut
645 1075
1076sub json_coder() {
1077 eval { require JSON::XS; JSON::XS->new->utf8 }
1078 || do { require JSON; JSON->new->utf8 }
1079}
1080
646register_write_type json => sub { 1081register_write_type json => sub {
647 my ($self, $ref) = @_; 1082 my ($self, $ref) = @_;
648 1083
649 require JSON; 1084 my $json = $self->{json} ||= json_coder;
650 1085
651 $self->{json} ? $self->{json}->encode ($ref) 1086 $json->encode ($ref)
652 : JSON::encode_json ($ref)
653}; 1087};
654 1088
655=item storable => $reference 1089=item storable => $reference
656 1090
657Freezes the given reference using L<Storable> and writes it to the 1091Freezes the given reference using L<Storable> and writes it to the
660=cut 1094=cut
661 1095
662register_write_type storable => sub { 1096register_write_type storable => sub {
663 my ($self, $ref) = @_; 1097 my ($self, $ref) = @_;
664 1098
665 require Storable; 1099 require Storable unless $Storable::VERSION;
666 1100
667 pack "w/a*", Storable::nfreeze ($ref) 1101 pack "w/a*", Storable::nfreeze ($ref)
668}; 1102};
669 1103
670=back 1104=back
671 1105
672=item AnyEvent::Handle::register_write_type type => $coderef->($handle, @args) 1106=item $handle->push_shutdown
673 1107
674This function (not method) lets you add your own types to C<push_write>. 1108Sometimes you know you want to close the socket after writing your data
1109before it was actually written. One way to do that is to replace your
1110C<on_drain> handler by a callback that shuts down the socket (and set
1111C<low_water_mark> to C<0>). This method is a shorthand for just that, and
1112replaces the C<on_drain> callback with:
1113
1114 sub { shutdown $_[0]{fh}, 1 }
1115
1116This simply shuts down the write side and signals an EOF condition to the
1117the peer.
1118
1119You can rely on the normal read queue and C<on_eof> handling
1120afterwards. This is the cleanest way to close a connection.
1121
1122This method may invoke callbacks (and therefore the handle might be
1123destroyed after it returns).
1124
1125=cut
1126
1127sub push_shutdown {
1128 my ($self) = @_;
1129
1130 delete $self->{low_water_mark};
1131 $self->on_drain (sub { shutdown $_[0]{fh}, 1 });
1132}
1133
1134=item custom write types - Package::anyevent_write_type $handle, @args
1135
1136Instead of one of the predefined types, you can also specify the name of
1137a package. AnyEvent will try to load the package and then expects to find
1138a function named C<anyevent_write_type> inside. If it isn't found, it
1139progressively tries to load the parent package until it either finds the
1140function (good) or runs out of packages (bad).
1141
675Whenever the given C<type> is used, C<push_write> will invoke the code 1142Whenever the given C<type> is used, C<push_write> will the function with
676reference with the handle object and the remaining arguments. 1143the handle object and the remaining arguments.
677 1144
678The code reference is supposed to return a single octet string that will 1145The function is supposed to return a single octet string that will be
679be appended to the write buffer. 1146appended to the write buffer, so you can mentally treat this function as a
1147"arguments to on-the-wire-format" converter.
680 1148
681Note that this is a function, and all types registered this way will be 1149Example: implement a custom write type C<join> that joins the remaining
682global, so try to use unique names. 1150arguments using the first one.
1151
1152 $handle->push_write (My::Type => " ", 1,2,3);
1153
1154 # uses the following package, which can be defined in the "My::Type" or in
1155 # the "My" modules to be auto-loaded, or just about anywhere when the
1156 # My::Type::anyevent_write_type is defined before invoking it.
1157
1158 package My::Type;
1159
1160 sub anyevent_write_type {
1161 my ($handle, $delim, @args) = @_;
1162
1163 join $delim, @args
1164 }
683 1165
684=cut 1166=cut
685 1167
686############################################################################# 1168#############################################################################
687 1169
696ways, the "simple" way, using only C<on_read> and the "complex" way, using 1178ways, the "simple" way, using only C<on_read> and the "complex" way, using
697a queue. 1179a queue.
698 1180
699In the simple case, you just install an C<on_read> callback and whenever 1181In the simple case, you just install an C<on_read> callback and whenever
700new data arrives, it will be called. You can then remove some data (if 1182new data arrives, it will be called. You can then remove some data (if
701enough is there) from the read buffer (C<< $handle->rbuf >>). Or you cna 1183enough is there) from the read buffer (C<< $handle->rbuf >>). Or you can
702leave the data there if you want to accumulate more (e.g. when only a 1184leave the data there if you want to accumulate more (e.g. when only a
703partial message has been received so far). 1185partial message has been received so far), or change the read queue with
1186e.g. C<push_read>.
704 1187
705In the more complex case, you want to queue multiple callbacks. In this 1188In the more complex case, you want to queue multiple callbacks. In this
706case, AnyEvent::Handle will call the first queued callback each time new 1189case, AnyEvent::Handle will call the first queued callback each time new
707data arrives (also the first time it is queued) and removes it when it has 1190data arrives (also the first time it is queued) and remove it when it has
708done its job (see C<push_read>, below). 1191done its job (see C<push_read>, below).
709 1192
710This way you can, for example, push three line-reads, followed by reading 1193This way you can, for example, push three line-reads, followed by reading
711a chunk of data, and AnyEvent::Handle will execute them in order. 1194a chunk of data, and AnyEvent::Handle will execute them in order.
712 1195
769=cut 1252=cut
770 1253
771sub _drain_rbuf { 1254sub _drain_rbuf {
772 my ($self) = @_; 1255 my ($self) = @_;
773 1256
1257 # avoid recursion
1258 return if $self->{_skip_drain_rbuf};
774 local $self->{_in_drain} = 1; 1259 local $self->{_skip_drain_rbuf} = 1;
775
776 if (
777 defined $self->{rbuf_max}
778 && $self->{rbuf_max} < length $self->{rbuf}
779 ) {
780 $self->_error (&Errno::ENOSPC, 1), return;
781 }
782 1260
783 while () { 1261 while () {
784 # we need to use a separate tls read buffer, as we must not receive data while 1262 # we need to use a separate tls read buffer, as we must not receive data while
785 # we are draining the buffer, and this can only happen with TLS. 1263 # we are draining the buffer, and this can only happen with TLS.
786 $self->{rbuf} .= delete $self->{_tls_rbuf} if exists $self->{_tls_rbuf}; 1264 $self->{rbuf} .= delete $self->{_tls_rbuf}
1265 if exists $self->{_tls_rbuf};
787 1266
788 my $len = length $self->{rbuf}; 1267 my $len = length $self->{rbuf};
789 1268
790 if (my $cb = shift @{ $self->{_queue} }) { 1269 if (my $cb = shift @{ $self->{_queue} }) {
791 unless ($cb->($self)) { 1270 unless ($cb->($self)) {
792 if ($self->{_eof}) { 1271 # no progress can be made
793 # no progress can be made (not enough data and no data forthcoming) 1272 # (not enough data and no data forthcoming)
794 $self->_error (&Errno::EPIPE, 1), return; 1273 $self->_error (Errno::EPIPE, 1), return
795 } 1274 if $self->{_eof};
796 1275
797 unshift @{ $self->{_queue} }, $cb; 1276 unshift @{ $self->{_queue} }, $cb;
798 last; 1277 last;
799 } 1278 }
800 } elsif ($self->{on_read}) { 1279 } elsif ($self->{on_read}) {
807 && !@{ $self->{_queue} } # and the queue is still empty 1286 && !@{ $self->{_queue} } # and the queue is still empty
808 && $self->{on_read} # but we still have on_read 1287 && $self->{on_read} # but we still have on_read
809 ) { 1288 ) {
810 # no further data will arrive 1289 # no further data will arrive
811 # so no progress can be made 1290 # so no progress can be made
812 $self->_error (&Errno::EPIPE, 1), return 1291 $self->_error (Errno::EPIPE, 1), return
813 if $self->{_eof}; 1292 if $self->{_eof};
814 1293
815 last; # more data might arrive 1294 last; # more data might arrive
816 } 1295 }
817 } else { 1296 } else {
820 last; 1299 last;
821 } 1300 }
822 } 1301 }
823 1302
824 if ($self->{_eof}) { 1303 if ($self->{_eof}) {
825 if ($self->{on_eof}) { 1304 $self->{on_eof}
826 $self->{on_eof}($self) 1305 ? $self->{on_eof}($self)
827 } else { 1306 : $self->_error (0, 1, "Unexpected end-of-file");
828 $self->_error (0, 1); 1307
829 } 1308 return;
1309 }
1310
1311 if (
1312 defined $self->{rbuf_max}
1313 && $self->{rbuf_max} < length $self->{rbuf}
1314 ) {
1315 $self->_error (Errno::ENOSPC, 1), return;
830 } 1316 }
831 1317
832 # may need to restart read watcher 1318 # may need to restart read watcher
833 unless ($self->{_rw}) { 1319 unless ($self->{_rw}) {
834 $self->start_read 1320 $self->start_read
840 1326
841This replaces the currently set C<on_read> callback, or clears it (when 1327This replaces the currently set C<on_read> callback, or clears it (when
842the new callback is C<undef>). See the description of C<on_read> in the 1328the new callback is C<undef>). See the description of C<on_read> in the
843constructor. 1329constructor.
844 1330
1331This method may invoke callbacks (and therefore the handle might be
1332destroyed after it returns).
1333
845=cut 1334=cut
846 1335
847sub on_read { 1336sub on_read {
848 my ($self, $cb) = @_; 1337 my ($self, $cb) = @_;
849 1338
850 $self->{on_read} = $cb; 1339 $self->{on_read} = $cb;
851 $self->_drain_rbuf if $cb && !$self->{_in_drain}; 1340 $self->_drain_rbuf if $cb;
852} 1341}
853 1342
854=item $handle->rbuf 1343=item $handle->rbuf
855 1344
856Returns the read buffer (as a modifiable lvalue). 1345Returns the read buffer (as a modifiable lvalue). You can also access the
1346read buffer directly as the C<< ->{rbuf} >> member, if you want (this is
1347much faster, and no less clean).
857 1348
858You can access the read buffer directly as the C<< ->{rbuf} >> 1349The only operation allowed on the read buffer (apart from looking at it)
859member, if you want. However, the only operation allowed on the 1350is removing data from its beginning. Otherwise modifying or appending to
860read buffer (apart from looking at it) is removing data from its 1351it is not allowed and will lead to hard-to-track-down bugs.
861beginning. Otherwise modifying or appending to it is not allowed and will
862lead to hard-to-track-down bugs.
863 1352
864NOTE: The read buffer should only be used or modified if the C<on_read>, 1353NOTE: The read buffer should only be used or modified in the C<on_read>
865C<push_read> or C<unshift_read> methods are used. The other read methods 1354callback or when C<push_read> or C<unshift_read> are used with a single
866automatically manage the read buffer. 1355callback (i.e. untyped). Typed C<push_read> and C<unshift_read> methods
1356will manage the read buffer on their own.
867 1357
868=cut 1358=cut
869 1359
870sub rbuf : lvalue { 1360sub rbuf : lvalue {
871 $_[0]{rbuf} 1361 $_[0]{rbuf}
888 1378
889If enough data was available, then the callback must remove all data it is 1379If enough data was available, then the callback must remove all data it is
890interested in (which can be none at all) and return a true value. After returning 1380interested in (which can be none at all) and return a true value. After returning
891true, it will be removed from the queue. 1381true, it will be removed from the queue.
892 1382
1383These methods may invoke callbacks (and therefore the handle might be
1384destroyed after it returns).
1385
893=cut 1386=cut
894 1387
895our %RH; 1388our %RH;
896 1389
897sub register_read_type($$) { 1390sub register_read_type($$) {
903 my $cb = pop; 1396 my $cb = pop;
904 1397
905 if (@_) { 1398 if (@_) {
906 my $type = shift; 1399 my $type = shift;
907 1400
1401 $cb = ($RH{$type} ||= _load_func "$type\::anyevent_read_type"
908 $cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_read") 1402 or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::push_read")
909 ->($self, $cb, @_); 1403 ->($self, $cb, @_);
910 } 1404 }
911 1405
912 push @{ $self->{_queue} }, $cb; 1406 push @{ $self->{_queue} }, $cb;
913 $self->_drain_rbuf unless $self->{_in_drain}; 1407 $self->_drain_rbuf;
914} 1408}
915 1409
916sub unshift_read { 1410sub unshift_read {
917 my $self = shift; 1411 my $self = shift;
918 my $cb = pop; 1412 my $cb = pop;
919 1413
920 if (@_) { 1414 if (@_) {
921 my $type = shift; 1415 my $type = shift;
922 1416
1417 $cb = ($RH{$type} ||= _load_func "$type\::anyevent_read_type"
923 $cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::unshift_read") 1418 or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::unshift_read")
924 ->($self, $cb, @_); 1419 ->($self, $cb, @_);
925 } 1420 }
926 1421
927
928 unshift @{ $self->{_queue} }, $cb; 1422 unshift @{ $self->{_queue} }, $cb;
929 $self->_drain_rbuf unless $self->{_in_drain}; 1423 $self->_drain_rbuf;
930} 1424}
931 1425
932=item $handle->push_read (type => @args, $cb) 1426=item $handle->push_read (type => @args, $cb)
933 1427
934=item $handle->unshift_read (type => @args, $cb) 1428=item $handle->unshift_read (type => @args, $cb)
935 1429
936Instead of providing a callback that parses the data itself you can chose 1430Instead of providing a callback that parses the data itself you can chose
937between a number of predefined parsing formats, for chunks of data, lines 1431between a number of predefined parsing formats, for chunks of data, lines
938etc. 1432etc. You can also specify the (fully qualified) name of a package, in
1433which case AnyEvent tries to load the package and then expects to find the
1434C<anyevent_read_type> function inside (see "custom read types", below).
939 1435
940Predefined types are (if you have ideas for additional types, feel free to 1436Predefined types are (if you have ideas for additional types, feel free to
941drop by and tell us): 1437drop by and tell us):
942 1438
943=over 4 1439=over 4
949data. 1445data.
950 1446
951Example: read 2 bytes. 1447Example: read 2 bytes.
952 1448
953 $handle->push_read (chunk => 2, sub { 1449 $handle->push_read (chunk => 2, sub {
954 warn "yay ", unpack "H*", $_[1]; 1450 say "yay " . unpack "H*", $_[1];
955 }); 1451 });
956 1452
957=cut 1453=cut
958 1454
959register_read_type chunk => sub { 1455register_read_type chunk => sub {
993 if (@_ < 3) { 1489 if (@_ < 3) {
994 # this is more than twice as fast as the generic code below 1490 # this is more than twice as fast as the generic code below
995 sub { 1491 sub {
996 $_[0]{rbuf} =~ s/^([^\015\012]*)(\015?\012)// or return; 1492 $_[0]{rbuf} =~ s/^([^\015\012]*)(\015?\012)// or return;
997 1493
998 $cb->($_[0], $1, $2); 1494 $cb->($_[0], "$1", "$2");
999 1 1495 1
1000 } 1496 }
1001 } else { 1497 } else {
1002 $eol = quotemeta $eol unless ref $eol; 1498 $eol = quotemeta $eol unless ref $eol;
1003 $eol = qr|^(.*?)($eol)|s; 1499 $eol = qr|^(.*?)($eol)|s;
1004 1500
1005 sub { 1501 sub {
1006 $_[0]{rbuf} =~ s/$eol// or return; 1502 $_[0]{rbuf} =~ s/$eol// or return;
1007 1503
1008 $cb->($_[0], $1, $2); 1504 $cb->($_[0], "$1", "$2");
1009 1 1505 1
1010 } 1506 }
1011 } 1507 }
1012}; 1508};
1013 1509
1035the receive buffer when neither C<$accept> nor C<$reject> match, 1531the receive buffer when neither C<$accept> nor C<$reject> match,
1036and everything preceding and including the match will be accepted 1532and everything preceding and including the match will be accepted
1037unconditionally. This is useful to skip large amounts of data that you 1533unconditionally. This is useful to skip large amounts of data that you
1038know cannot be matched, so that the C<$accept> or C<$reject> regex do not 1534know cannot be matched, so that the C<$accept> or C<$reject> regex do not
1039have to start matching from the beginning. This is purely an optimisation 1535have to start matching from the beginning. This is purely an optimisation
1040and is usually worth only when you expect more than a few kilobytes. 1536and is usually worth it only when you expect more than a few kilobytes.
1041 1537
1042Example: expect a http header, which ends at C<\015\012\015\012>. Since we 1538Example: expect a http header, which ends at C<\015\012\015\012>. Since we
1043expect the header to be very large (it isn't in practise, but...), we use 1539expect the header to be very large (it isn't in practice, but...), we use
1044a skip regex to skip initial portions. The skip regex is tricky in that 1540a skip regex to skip initial portions. The skip regex is tricky in that
1045it only accepts something not ending in either \015 or \012, as these are 1541it only accepts something not ending in either \015 or \012, as these are
1046required for the accept regex. 1542required for the accept regex.
1047 1543
1048 $handle->push_read (regex => 1544 $handle->push_read (regex =>
1061 1557
1062 sub { 1558 sub {
1063 # accept 1559 # accept
1064 if ($$rbuf =~ $accept) { 1560 if ($$rbuf =~ $accept) {
1065 $data .= substr $$rbuf, 0, $+[0], ""; 1561 $data .= substr $$rbuf, 0, $+[0], "";
1066 $cb->($self, $data); 1562 $cb->($_[0], $data);
1067 return 1; 1563 return 1;
1068 } 1564 }
1069 1565
1070 # reject 1566 # reject
1071 if ($reject && $$rbuf =~ $reject) { 1567 if ($reject && $$rbuf =~ $reject) {
1072 $self->_error (&Errno::EBADMSG); 1568 $_[0]->_error (Errno::EBADMSG);
1073 } 1569 }
1074 1570
1075 # skip 1571 # skip
1076 if ($skip && $$rbuf =~ $skip) { 1572 if ($skip && $$rbuf =~ $skip) {
1077 $data .= substr $$rbuf, 0, $+[0], ""; 1573 $data .= substr $$rbuf, 0, $+[0], "";
1093 my ($self, $cb) = @_; 1589 my ($self, $cb) = @_;
1094 1590
1095 sub { 1591 sub {
1096 unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) { 1592 unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
1097 if ($_[0]{rbuf} =~ /[^0-9]/) { 1593 if ($_[0]{rbuf} =~ /[^0-9]/) {
1098 $self->_error (&Errno::EBADMSG); 1594 $_[0]->_error (Errno::EBADMSG);
1099 } 1595 }
1100 return; 1596 return;
1101 } 1597 }
1102 1598
1103 my $len = $1; 1599 my $len = $1;
1104 1600
1105 $self->unshift_read (chunk => $len, sub { 1601 $_[0]->unshift_read (chunk => $len, sub {
1106 my $string = $_[1]; 1602 my $string = $_[1];
1107 $_[0]->unshift_read (chunk => 1, sub { 1603 $_[0]->unshift_read (chunk => 1, sub {
1108 if ($_[1] eq ",") { 1604 if ($_[1] eq ",") {
1109 $cb->($_[0], $string); 1605 $cb->($_[0], $string);
1110 } else { 1606 } else {
1111 $self->_error (&Errno::EBADMSG); 1607 $_[0]->_error (Errno::EBADMSG);
1112 } 1608 }
1113 }); 1609 });
1114 }); 1610 });
1115 1611
1116 1 1612 1
1183=cut 1679=cut
1184 1680
1185register_read_type json => sub { 1681register_read_type json => sub {
1186 my ($self, $cb) = @_; 1682 my ($self, $cb) = @_;
1187 1683
1188 require JSON; 1684 my $json = $self->{json} ||= json_coder;
1189 1685
1190 my $data; 1686 my $data;
1191 my $rbuf = \$self->{rbuf}; 1687 my $rbuf = \$self->{rbuf};
1192 1688
1193 my $json = $self->{json} ||= JSON->new->utf8;
1194
1195 sub { 1689 sub {
1196 my $ref = eval { $json->incr_parse ($self->{rbuf}) }; 1690 my $ref = eval { $json->incr_parse ($_[0]{rbuf}) };
1197 1691
1198 if ($ref) { 1692 if ($ref) {
1199 $self->{rbuf} = $json->incr_text; 1693 $_[0]{rbuf} = $json->incr_text;
1200 $json->incr_text = ""; 1694 $json->incr_text = "";
1201 $cb->($self, $ref); 1695 $cb->($_[0], $ref);
1202 1696
1203 1 1697 1
1204 } elsif ($@) { 1698 } elsif ($@) {
1205 # error case 1699 # error case
1206 $json->incr_skip; 1700 $json->incr_skip;
1207 1701
1208 $self->{rbuf} = $json->incr_text; 1702 $_[0]{rbuf} = $json->incr_text;
1209 $json->incr_text = ""; 1703 $json->incr_text = "";
1210 1704
1211 $self->_error (&Errno::EBADMSG); 1705 $_[0]->_error (Errno::EBADMSG);
1212 1706
1213 () 1707 ()
1214 } else { 1708 } else {
1215 $self->{rbuf} = ""; 1709 $_[0]{rbuf} = "";
1216 1710
1217 () 1711 ()
1218 } 1712 }
1219 } 1713 }
1220}; 1714};
1230=cut 1724=cut
1231 1725
1232register_read_type storable => sub { 1726register_read_type storable => sub {
1233 my ($self, $cb) = @_; 1727 my ($self, $cb) = @_;
1234 1728
1235 require Storable; 1729 require Storable unless $Storable::VERSION;
1236 1730
1237 sub { 1731 sub {
1238 # when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method 1732 # when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
1239 defined (my $len = eval { unpack "w", $_[0]{rbuf} }) 1733 defined (my $len = eval { unpack "w", $_[0]{rbuf} })
1240 or return; 1734 or return;
1243 1737
1244 # bypass unshift if we already have the remaining chunk 1738 # bypass unshift if we already have the remaining chunk
1245 if ($format + $len <= length $_[0]{rbuf}) { 1739 if ($format + $len <= length $_[0]{rbuf}) {
1246 my $data = substr $_[0]{rbuf}, $format, $len; 1740 my $data = substr $_[0]{rbuf}, $format, $len;
1247 substr $_[0]{rbuf}, 0, $format + $len, ""; 1741 substr $_[0]{rbuf}, 0, $format + $len, "";
1742
1248 $cb->($_[0], Storable::thaw ($data)); 1743 eval { $cb->($_[0], Storable::thaw ($data)); 1 }
1744 or return $_[0]->_error (Errno::EBADMSG);
1249 } else { 1745 } else {
1250 # remove prefix 1746 # remove prefix
1251 substr $_[0]{rbuf}, 0, $format, ""; 1747 substr $_[0]{rbuf}, 0, $format, "";
1252 1748
1253 # read remaining chunk 1749 # read remaining chunk
1254 $_[0]->unshift_read (chunk => $len, sub { 1750 $_[0]->unshift_read (chunk => $len, sub {
1255 if (my $ref = eval { Storable::thaw ($_[1]) }) { 1751 eval { $cb->($_[0], Storable::thaw ($_[1])); 1 }
1256 $cb->($_[0], $ref);
1257 } else {
1258 $self->_error (&Errno::EBADMSG); 1752 or $_[0]->_error (Errno::EBADMSG);
1259 }
1260 }); 1753 });
1261 } 1754 }
1262 1755
1263 1 1756 1
1264 } 1757 }
1265}; 1758};
1266 1759
1760=item tls_detect => $cb->($handle, $detect, $major, $minor)
1761
1762Checks the input stream for a valid SSL or TLS handshake TLSPaintext
1763record without consuming anything. Only SSL version 3 or higher
1764is handled, up to the fictituous protocol 4.x (but both SSL3+ and
1765SSL2-compatible framing is supported).
1766
1767If it detects that the input data is likely TLS, it calls the callback
1768with a true value for C<$detect> and the (on-wire) TLS version as second
1769and third argument (C<$major> is C<3>, and C<$minor> is 0..3 for SSL
17703.0, TLS 1.0, 1.1 and 1.2, respectively). If it detects the input to
1771be definitely not TLS, it calls the callback with a false value for
1772C<$detect>.
1773
1774The callback could use this information to decide whether or not to start
1775TLS negotiation.
1776
1777In all cases the data read so far is passed to the following read
1778handlers.
1779
1780Usually you want to use the C<tls_autostart> read type instead.
1781
1782If you want to design a protocol that works in the presence of TLS
1783dtection, make sure that any non-TLS data doesn't start with the octet 22
1784(ASCII SYN, 16 hex) or 128-255 (i.e. highest bit set). The checks this
1785read type does are a bit more strict, but might losen in the future to
1786accomodate protocol changes.
1787
1788This read type does not rely on L<AnyEvent::TLS> (and thus, not on
1789L<Net::SSLeay>).
1790
1791=item tls_autostart => $tls[, $tls_ctx]
1792
1793Tries to detect a valid SSL or TLS handshake. If one is detected, it tries
1794to start tls by calling C<starttls> with the given arguments.
1795
1796In practise, C<$tls> must be C<accept>, or a Net::SSLeay context that has
1797been configured to accept, as servers do not normally send a handshake on
1798their own and ths cannot be detected in this way.
1799
1800See C<tls_detect> above for more details.
1801
1802Example: give the client a chance to start TLS before accepting a text
1803line.
1804
1805 $hdl->push_read (tls_detect => "accept");
1806 $hdl->push_read (line => sub {
1807 print "received ", ($_[0]{tls} ? "encrypted" : "cleartext"), " <$_[1]>\n";
1808 });
1809
1810=cut
1811
1812register_read_type tls_detect => sub {
1813 my ($self, $cb) = @_;
1814
1815 sub {
1816 # this regex matches a full or partial tls record
1817 if (
1818 # ssl3+: type(22=handshake) major(=3) minor(any) length_hi
1819 $self->{rbuf} =~ /^(?:\z| \x16 (\z| [\x03\x04] (?:\z| . (?:\z| [\x00-\x40] ))))/xs
1820 # ssl2 comapatible: len_hi len_lo type(1) major minor dummy(forlength)
1821 or $self->{rbuf} =~ /^(?:\z| [\x80-\xff] (?:\z| . (?:\z| \x01 (\z| [\x03\x04] (?:\z| . (?:\z| . ))))))/xs
1822 ) {
1823 return if 3 != length $1; # partial match, can't decide yet
1824
1825 # full match, valid TLS record
1826 my ($major, $minor) = unpack "CC", $1;
1827 $cb->($self, "accept", $major + $minor * 0.1);
1828 } else {
1829 # mismatch == guaranteed not TLS
1830 $cb->($self, undef);
1831 }
1832
1833 1
1834 }
1835};
1836
1837register_read_type tls_autostart => sub {
1838 my ($self, @tls) = @_;
1839
1840 $RH{tls_detect}($self, sub {
1841 return unless $_[1];
1842 $_[0]->starttls (@tls);
1843 })
1844};
1845
1267=back 1846=back
1268 1847
1269=item AnyEvent::Handle::register_read_type type => $coderef->($handle, $cb, @args) 1848=item custom read types - Package::anyevent_read_type $handle, $cb, @args
1270 1849
1271This function (not method) lets you add your own types to C<push_read>. 1850Instead of one of the predefined types, you can also specify the name
1851of a package. AnyEvent will try to load the package and then expects to
1852find a function named C<anyevent_read_type> inside. If it isn't found, it
1853progressively tries to load the parent package until it either finds the
1854function (good) or runs out of packages (bad).
1272 1855
1273Whenever the given C<type> is used, C<push_read> will invoke the code 1856Whenever this type is used, C<push_read> will invoke the function with the
1274reference with the handle object, the callback and the remaining 1857handle object, the original callback and the remaining arguments.
1275arguments.
1276 1858
1277The code reference is supposed to return a callback (usually a closure) 1859The function is supposed to return a callback (usually a closure) that
1278that works as a plain read callback (see C<< ->push_read ($cb) >>). 1860works as a plain read callback (see C<< ->push_read ($cb) >>), so you can
1861mentally treat the function as a "configurable read type to read callback"
1862converter.
1279 1863
1280It should invoke the passed callback when it is done reading (remember to 1864It should invoke the original callback when it is done reading (remember
1281pass C<$handle> as first argument as all other callbacks do that). 1865to pass C<$handle> as first argument as all other callbacks do that,
1866although there is no strict requirement on this).
1282 1867
1283Note that this is a function, and all types registered this way will be
1284global, so try to use unique names.
1285
1286For examples, see the source of this module (F<perldoc -m AnyEvent::Handle>, 1868For examples, see the source of this module (F<perldoc -m
1287search for C<register_read_type>)). 1869AnyEvent::Handle>, search for C<register_read_type>)).
1288 1870
1289=item $handle->stop_read 1871=item $handle->stop_read
1290 1872
1291=item $handle->start_read 1873=item $handle->start_read
1292 1874
1298Note that AnyEvent::Handle will automatically C<start_read> for you when 1880Note that AnyEvent::Handle will automatically C<start_read> for you when
1299you change the C<on_read> callback or push/unshift a read callback, and it 1881you change the C<on_read> callback or push/unshift a read callback, and it
1300will automatically C<stop_read> for you when neither C<on_read> is set nor 1882will automatically C<stop_read> for you when neither C<on_read> is set nor
1301there are any read requests in the queue. 1883there are any read requests in the queue.
1302 1884
1303These methods will have no effect when in TLS mode (as TLS doesn't support 1885In older versions of this module (<= 5.3), these methods had no effect,
1304half-duplex connections). 1886as TLS does not support half-duplex connections. In current versions they
1887work as expected, as this behaviour is required to avoid certain resource
1888attacks, where the program would be forced to read (and buffer) arbitrary
1889amounts of data before being able to send some data. The drawback is that
1890some readings of the the SSL/TLS specifications basically require this
1891attack to be working, as SSL/TLS implementations might stall sending data
1892during a rehandshake.
1893
1894As a guideline, during the initial handshake, you should not stop reading,
1895and as a client, it might cause problems, depending on your application.
1305 1896
1306=cut 1897=cut
1307 1898
1308sub stop_read { 1899sub stop_read {
1309 my ($self) = @_; 1900 my ($self) = @_;
1310 1901
1311 delete $self->{_rw} unless $self->{tls}; 1902 delete $self->{_rw};
1312} 1903}
1313 1904
1314sub start_read { 1905sub start_read {
1315 my ($self) = @_; 1906 my ($self) = @_;
1316 1907
1317 unless ($self->{_rw} || $self->{_eof}) { 1908 unless ($self->{_rw} || $self->{_eof} || !$self->{fh}) {
1318 Scalar::Util::weaken $self; 1909 Scalar::Util::weaken $self;
1319 1910
1320 $self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub { 1911 $self->{_rw} = AE::io $self->{fh}, 0, sub {
1321 my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf}); 1912 my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf});
1322 my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf; 1913 my $len = sysread $self->{fh}, $$rbuf, $self->{read_size}, length $$rbuf;
1323 1914
1324 if ($len > 0) { 1915 if ($len > 0) {
1325 $self->{_activity} = AnyEvent->now; 1916 $self->{_activity} = $self->{_ractivity} = AE::now;
1326 1917
1327 if ($self->{tls}) { 1918 if ($self->{tls}) {
1328 Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf); 1919 Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf);
1329 1920
1330 &_dotls ($self); 1921 &_dotls ($self);
1331 } else { 1922 } else {
1332 $self->_drain_rbuf unless $self->{_in_drain}; 1923 $self->_drain_rbuf;
1924 }
1925
1926 if ($len == $self->{read_size}) {
1927 $self->{read_size} *= 2;
1928 $self->{read_size} = $self->{max_read_size} || MAX_READ_SIZE
1929 if $self->{read_size} > ($self->{max_read_size} || MAX_READ_SIZE);
1333 } 1930 }
1334 1931
1335 } elsif (defined $len) { 1932 } elsif (defined $len) {
1336 delete $self->{_rw}; 1933 delete $self->{_rw};
1337 $self->{_eof} = 1; 1934 $self->{_eof} = 1;
1338 $self->_drain_rbuf unless $self->{_in_drain}; 1935 $self->_drain_rbuf;
1339 1936
1340 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) { 1937 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
1341 return $self->_error ($!, 1); 1938 return $self->_error ($!, 1);
1342 } 1939 }
1343 }); 1940 };
1941 }
1942}
1943
1944our $ERROR_SYSCALL;
1945our $ERROR_WANT_READ;
1946
1947sub _tls_error {
1948 my ($self, $err) = @_;
1949
1950 return $self->_error ($!, 1)
1951 if $err == Net::SSLeay::ERROR_SYSCALL ();
1952
1953 my $err = Net::SSLeay::ERR_error_string (Net::SSLeay::ERR_get_error ());
1954
1955 # reduce error string to look less scary
1956 $err =~ s/^error:[0-9a-fA-F]{8}:[^:]+:([^:]+):/\L$1: /;
1957
1958 if ($self->{_on_starttls}) {
1959 (delete $self->{_on_starttls})->($self, undef, $err);
1960 &_freetls;
1961 } else {
1962 &_freetls;
1963 $self->_error (Errno::EPROTO, 1, $err);
1344 } 1964 }
1345} 1965}
1346 1966
1347# poll the write BIO and send the data if applicable 1967# poll the write BIO and send the data if applicable
1968# also decode read data if possible
1969# this is basiclaly our TLS state machine
1970# more efficient implementations are possible with openssl,
1971# but not with the buggy and incomplete Net::SSLeay.
1348sub _dotls { 1972sub _dotls {
1349 my ($self) = @_; 1973 my ($self) = @_;
1350 1974
1351 my $tmp; 1975 my $tmp;
1352 1976
1353 if (length $self->{_tls_wbuf}) { 1977 if (length $self->{_tls_wbuf}) {
1354 while (($tmp = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) { 1978 while (($tmp = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) {
1355 substr $self->{_tls_wbuf}, 0, $tmp, ""; 1979 substr $self->{_tls_wbuf}, 0, $tmp, "";
1356 } 1980 }
1981
1982 $tmp = Net::SSLeay::get_error ($self->{tls}, $tmp);
1983 return $self->_tls_error ($tmp)
1984 if $tmp != $ERROR_WANT_READ
1985 && ($tmp != $ERROR_SYSCALL || $!);
1357 } 1986 }
1358 1987
1359 while (defined ($tmp = Net::SSLeay::read ($self->{tls}))) { 1988 while (defined ($tmp = Net::SSLeay::read ($self->{tls}))) {
1360 unless (length $tmp) { 1989 unless (length $tmp) {
1361 # let's treat SSL-eof as we treat normal EOF 1990 $self->{_on_starttls}
1362 delete $self->{_rw}; 1991 and (delete $self->{_on_starttls})->($self, undef, "EOF during handshake"); # ???
1363 $self->{_eof} = 1;
1364 &_freetls; 1992 &_freetls;
1993
1994 if ($self->{on_stoptls}) {
1995 $self->{on_stoptls}($self);
1996 return;
1997 } else {
1998 # let's treat SSL-eof as we treat normal EOF
1999 delete $self->{_rw};
2000 $self->{_eof} = 1;
2001 }
1365 } 2002 }
1366 2003
1367 $self->{_tls_rbuf} .= $tmp; 2004 $self->{_tls_rbuf} .= $tmp;
1368 $self->_drain_rbuf unless $self->{_in_drain}; 2005 $self->_drain_rbuf;
1369 $self->{tls} or return; # tls session might have gone away in callback 2006 $self->{tls} or return; # tls session might have gone away in callback
1370 } 2007 }
1371 2008
1372 $tmp = Net::SSLeay::get_error ($self->{tls}, -1); 2009 $tmp = Net::SSLeay::get_error ($self->{tls}, -1);
1373
1374 if ($tmp != Net::SSLeay::ERROR_WANT_READ ()) {
1375 if ($tmp == Net::SSLeay::ERROR_SYSCALL ()) {
1376 return $self->_error ($!, 1); 2010 return $self->_tls_error ($tmp)
1377 } elsif ($tmp == Net::SSLeay::ERROR_SSL ()) { 2011 if $tmp != $ERROR_WANT_READ
1378 return $self->_error (&Errno::EIO, 1); 2012 && ($tmp != $ERROR_SYSCALL || $!);
1379 }
1380
1381 # all other errors are fine for our purposes
1382 }
1383 2013
1384 while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) { 2014 while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) {
1385 $self->{wbuf} .= $tmp; 2015 $self->{wbuf} .= $tmp;
1386 $self->_drain_wbuf; 2016 $self->_drain_wbuf;
2017 $self->{tls} or return; # tls session might have gone away in callback
1387 } 2018 }
2019
2020 $self->{_on_starttls}
2021 and Net::SSLeay::state ($self->{tls}) == Net::SSLeay::ST_OK ()
2022 and (delete $self->{_on_starttls})->($self, 1, "TLS/SSL connection established");
1388} 2023}
1389 2024
1390=item $handle->starttls ($tls[, $tls_ctx]) 2025=item $handle->starttls ($tls[, $tls_ctx])
1391 2026
1392Instead of starting TLS negotiation immediately when the AnyEvent::Handle 2027Instead of starting TLS negotiation immediately when the AnyEvent::Handle
1393object is created, you can also do that at a later time by calling 2028object is created, you can also do that at a later time by calling
1394C<starttls>. 2029C<starttls>. See the C<tls> constructor argument for general info.
2030
2031Starting TLS is currently an asynchronous operation - when you push some
2032write data and then call C<< ->starttls >> then TLS negotiation will start
2033immediately, after which the queued write data is then sent. This might
2034change in future versions, so best make sure you have no outstanding write
2035data when calling this method.
1395 2036
1396The first argument is the same as the C<tls> constructor argument (either 2037The first argument is the same as the C<tls> constructor argument (either
1397C<"connect">, C<"accept"> or an existing Net::SSLeay object). 2038C<"connect">, C<"accept"> or an existing Net::SSLeay object).
1398 2039
1399The second argument is the optional C<AnyEvent::TLS> object that is used 2040The second argument is the optional C<AnyEvent::TLS> object that is used
1404The TLS connection object will end up in C<< $handle->{tls} >>, the TLS 2045The TLS connection object will end up in C<< $handle->{tls} >>, the TLS
1405context in C<< $handle->{tls_ctx} >> after this call and can be used or 2046context in C<< $handle->{tls_ctx} >> after this call and can be used or
1406changed to your liking. Note that the handshake might have already started 2047changed to your liking. Note that the handshake might have already started
1407when this function returns. 2048when this function returns.
1408 2049
1409If it an error to start a TLS handshake more than once per 2050Due to bugs in OpenSSL, it might or might not be possible to do multiple
1410AnyEvent::Handle object (this is due to bugs in OpenSSL). 2051handshakes on the same stream. It is best to not attempt to use the
2052stream after stopping TLS.
1411 2053
2054This method may invoke callbacks (and therefore the handle might be
2055destroyed after it returns).
2056
1412=cut 2057=cut
2058
2059our %TLS_CACHE; #TODO not yet documented, should we?
1413 2060
1414sub starttls { 2061sub starttls {
1415 my ($self, $ssl, $ctx) = @_; 2062 my ($self, $tls, $ctx) = @_;
1416 2063
1417 require Net::SSLeay; 2064 Carp::croak "It is an error to call starttls on an AnyEvent::Handle object while TLS is already active, caught"
1418
1419 Carp::croak "it is an error to call starttls more than once on an AnyEvent::Handle object"
1420 if $self->{tls}; 2065 if $self->{tls};
1421 2066
2067 unless (defined $AnyEvent::TLS::VERSION) {
2068 eval {
2069 require Net::SSLeay;
2070 require AnyEvent::TLS;
2071 1
2072 } or return $self->_error (Errno::EPROTO, 1, "TLS support not available on this system");
2073 }
2074
2075 $self->{tls} = $tls;
2076 $self->{tls_ctx} = $ctx if @_ > 2;
2077
2078 return unless $self->{fh};
2079
2080 $ERROR_SYSCALL = Net::SSLeay::ERROR_SYSCALL ();
2081 $ERROR_WANT_READ = Net::SSLeay::ERROR_WANT_READ ();
2082
2083 $tls = delete $self->{tls};
1422 $ctx ||= $self->{tls_ctx}; 2084 $ctx = $self->{tls_ctx};
2085
2086 local $Carp::CarpLevel = 1; # skip ourselves when creating a new context or session
1423 2087
1424 if ("HASH" eq ref $ctx) { 2088 if ("HASH" eq ref $ctx) {
1425 require AnyEvent::TLS; 2089 if ($ctx->{cache}) {
1426 2090 my $key = $ctx+0;
1427 local $Carp::CarpLevel = 1; # skip ourselves when creating a new context 2091 $ctx = $TLS_CACHE{$key} ||= new AnyEvent::TLS %$ctx;
2092 } else {
1428 $ctx = new AnyEvent::TLS %$ctx; 2093 $ctx = new AnyEvent::TLS %$ctx;
2094 }
1429 } 2095 }
1430 2096
1431 $self->{tls_ctx} = $ctx || TLS_CTX (); 2097 $self->{tls_ctx} = $ctx || TLS_CTX ();
1432 $self->{tls} = $ssl = $self->{tls_ctx}->_get_session ($ssl, $self); 2098 $self->{tls} = $tls = $self->{tls_ctx}->_get_session ($tls, $self, $self->{peername});
1433 2099
1434 # basically, this is deep magic (because SSL_read should have the same issues) 2100 # basically, this is deep magic (because SSL_read should have the same issues)
1435 # but the openssl maintainers basically said: "trust us, it just works". 2101 # but the openssl maintainers basically said: "trust us, it just works".
1436 # (unfortunately, we have to hardcode constants because the abysmally misdesigned 2102 # (unfortunately, we have to hardcode constants because the abysmally misdesigned
1437 # and mismaintained ssleay-module doesn't even offer them). 2103 # and mismaintained ssleay-module doesn't even offer them).
1444 # and we drive openssl fully in blocking mode here. Or maybe we don't - openssl seems to 2110 # and we drive openssl fully in blocking mode here. Or maybe we don't - openssl seems to
1445 # have identity issues in that area. 2111 # have identity issues in that area.
1446# Net::SSLeay::CTX_set_mode ($ssl, 2112# Net::SSLeay::CTX_set_mode ($ssl,
1447# (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1) 2113# (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)
1448# | (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2)); 2114# | (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2));
1449 Net::SSLeay::CTX_set_mode ($ssl, 1|2); 2115 Net::SSLeay::CTX_set_mode ($tls, 1|2);
1450 2116
1451 $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); 2117 $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1452 $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); 2118 $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1453 2119
2120 Net::SSLeay::BIO_write ($self->{_rbio}, $self->{rbuf});
2121 $self->{rbuf} = "";
2122
1454 Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio}); 2123 Net::SSLeay::set_bio ($tls, $self->{_rbio}, $self->{_wbio});
2124
2125 $self->{_on_starttls} = sub { $_[0]{on_starttls}(@_) }
2126 if $self->{on_starttls};
1455 2127
1456 &_dotls; # need to trigger the initial handshake 2128 &_dotls; # need to trigger the initial handshake
1457 $self->start_read; # make sure we actually do read 2129 $self->start_read; # make sure we actually do read
1458} 2130}
1459 2131
1460=item $handle->stoptls 2132=item $handle->stoptls
1461 2133
1462Shuts down the SSL connection - this makes a proper EOF handshake by 2134Shuts down the SSL connection - this makes a proper EOF handshake by
1463sending a close notify to the other side, but since OpenSSL doesn't 2135sending a close notify to the other side, but since OpenSSL doesn't
1464support non-blocking shut downs, it is not possible to re-use the stream 2136support non-blocking shut downs, it is not guaranteed that you can re-use
1465afterwards. 2137the stream afterwards.
2138
2139This method may invoke callbacks (and therefore the handle might be
2140destroyed after it returns).
1466 2141
1467=cut 2142=cut
1468 2143
1469sub stoptls { 2144sub stoptls {
1470 my ($self) = @_; 2145 my ($self) = @_;
1471 2146
1472 if ($self->{tls}) { 2147 if ($self->{tls} && $self->{fh}) {
1473 Net::SSLeay::shutdown ($self->{tls}); 2148 Net::SSLeay::shutdown ($self->{tls});
1474 2149
1475 &_dotls; 2150 &_dotls;
1476 2151
1477 # we don't give a shit. no, we do, but we can't. no... 2152# # we don't give a shit. no, we do, but we can't. no...#d#
1478 # we, we... have to use openssl :/ 2153# # we, we... have to use openssl :/#d#
1479 &_freetls; 2154# &_freetls;#d#
1480 } 2155 }
1481} 2156}
1482 2157
1483sub _freetls { 2158sub _freetls {
1484 my ($self) = @_; 2159 my ($self) = @_;
1485 2160
1486 return unless $self->{tls}; 2161 return unless $self->{tls};
1487 2162
1488 $self->{tls_ctx}->_put_session (delete $self->{tls}); 2163 $self->{tls_ctx}->_put_session (delete $self->{tls})
2164 if $self->{tls} > 0;
1489 2165
1490 delete @$self{qw(_rbio _wbio _tls_wbuf)}; 2166 delete @$self{qw(_rbio _wbio _tls_wbuf _on_starttls)};
1491} 2167}
2168
2169=item $handle->resettls
2170
2171This rarely-used method simply resets and TLS state on the handle, usually
2172causing data loss.
2173
2174One case where it may be useful is when you want to skip over the data in
2175the stream but you are not interested in interpreting it, so data loss is
2176no concern.
2177
2178=cut
2179
2180*resettls = \&_freetls;
1492 2181
1493sub DESTROY { 2182sub DESTROY {
1494 my ($self) = @_; 2183 my ($self) = @_;
1495 2184
1496 &_freetls; 2185 &_freetls;
1497 2186
1498 my $linger = exists $self->{linger} ? $self->{linger} : 3600; 2187 my $linger = exists $self->{linger} ? $self->{linger} : 3600;
1499 2188
1500 if ($linger && length $self->{wbuf}) { 2189 if ($linger && length $self->{wbuf} && $self->{fh}) {
1501 my $fh = delete $self->{fh}; 2190 my $fh = delete $self->{fh};
1502 my $wbuf = delete $self->{wbuf}; 2191 my $wbuf = delete $self->{wbuf};
1503 2192
1504 my @linger; 2193 my @linger;
1505 2194
1506 push @linger, AnyEvent->io (fh => $fh, poll => "w", cb => sub { 2195 push @linger, AE::io $fh, 1, sub {
1507 my $len = syswrite $fh, $wbuf, length $wbuf; 2196 my $len = syswrite $fh, $wbuf, length $wbuf;
1508 2197
1509 if ($len > 0) { 2198 if ($len > 0) {
1510 substr $wbuf, 0, $len, ""; 2199 substr $wbuf, 0, $len, "";
1511 } else { 2200 } elsif (defined $len || ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK)) {
1512 @linger = (); # end 2201 @linger = (); # end
1513 } 2202 }
1514 }); 2203 };
1515 push @linger, AnyEvent->timer (after => $linger, cb => sub { 2204 push @linger, AE::timer $linger, 0, sub {
1516 @linger = (); 2205 @linger = ();
1517 }); 2206 };
1518 } 2207 }
1519} 2208}
1520 2209
1521=item $handle->destroy 2210=item $handle->destroy
1522 2211
1523Shuts down the handle object as much as possible - this call ensures that 2212Shuts down the handle object as much as possible - this call ensures that
1524no further callbacks will be invoked and resources will be freed as much 2213no further callbacks will be invoked and as many resources as possible
1525as possible. You must not call any methods on the object afterwards. 2214will be freed. Any method you will call on the handle object after
2215destroying it in this way will be silently ignored (and it will return the
2216empty list).
1526 2217
1527Normally, you can just "forget" any references to an AnyEvent::Handle 2218Normally, you can just "forget" any references to an AnyEvent::Handle
1528object and it will simply shut down. This works in fatal error and EOF 2219object and it will simply shut down. This works in fatal error and EOF
1529callbacks, as well as code outside. It does I<NOT> work in a read or write 2220callbacks, as well as code outside. It does I<NOT> work in a read or write
1530callback, so when you want to destroy the AnyEvent::Handle object from 2221callback, so when you want to destroy the AnyEvent::Handle object from
1531within such an callback. You I<MUST> call C<< ->destroy >> explicitly in 2222within such an callback. You I<MUST> call C<< ->destroy >> explicitly in
1532that case. 2223that case.
1533 2224
2225Destroying the handle object in this way has the advantage that callbacks
2226will be removed as well, so if those are the only reference holders (as
2227is common), then one doesn't need to do anything special to break any
2228reference cycles.
2229
1534The handle might still linger in the background and write out remaining 2230The handle might still linger in the background and write out remaining
1535data, as specified by the C<linger> option, however. 2231data, as specified by the C<linger> option, however.
1536 2232
1537=cut 2233=cut
1538 2234
1539sub destroy { 2235sub destroy {
1540 my ($self) = @_; 2236 my ($self) = @_;
1541 2237
1542 $self->DESTROY; 2238 $self->DESTROY;
1543 %$self = (); 2239 %$self = ();
2240 bless $self, "AnyEvent::Handle::destroyed";
1544} 2241}
2242
2243sub AnyEvent::Handle::destroyed::AUTOLOAD {
2244 #nop
2245}
2246
2247=item $handle->destroyed
2248
2249Returns false as long as the handle hasn't been destroyed by a call to C<<
2250->destroy >>, true otherwise.
2251
2252Can be useful to decide whether the handle is still valid after some
2253callback possibly destroyed the handle. For example, C<< ->push_write >>,
2254C<< ->starttls >> and other methods can call user callbacks, which in turn
2255can destroy the handle, so work can be avoided by checking sometimes:
2256
2257 $hdl->starttls ("accept");
2258 return if $hdl->destroyed;
2259 $hdl->push_write (...
2260
2261Note that the call to C<push_write> will silently be ignored if the handle
2262has been destroyed, so often you can just ignore the possibility of the
2263handle being destroyed.
2264
2265=cut
2266
2267sub destroyed { 0 }
2268sub AnyEvent::Handle::destroyed::destroyed { 1 }
1545 2269
1546=item AnyEvent::Handle::TLS_CTX 2270=item AnyEvent::Handle::TLS_CTX
1547 2271
1548This function creates and returns the AnyEvent::TLS object used by default 2272This function creates and returns the AnyEvent::TLS object used by default
1549for TLS mode. 2273for TLS mode.
1577 2301
1578It is only safe to "forget" the reference inside EOF or error callbacks, 2302It is only safe to "forget" the reference inside EOF or error callbacks,
1579from within all other callbacks, you need to explicitly call the C<< 2303from within all other callbacks, you need to explicitly call the C<<
1580->destroy >> method. 2304->destroy >> method.
1581 2305
2306=item Why is my C<on_eof> callback never called?
2307
2308Probably because your C<on_error> callback is being called instead: When
2309you have outstanding requests in your read queue, then an EOF is
2310considered an error as you clearly expected some data.
2311
2312To avoid this, make sure you have an empty read queue whenever your handle
2313is supposed to be "idle" (i.e. connection closes are O.K.). You can set
2314an C<on_read> handler that simply pushes the first read requests in the
2315queue.
2316
2317See also the next question, which explains this in a bit more detail.
2318
2319=item How can I serve requests in a loop?
2320
2321Most protocols consist of some setup phase (authentication for example)
2322followed by a request handling phase, where the server waits for requests
2323and handles them, in a loop.
2324
2325There are two important variants: The first (traditional, better) variant
2326handles requests until the server gets some QUIT command, causing it to
2327close the connection first (highly desirable for a busy TCP server). A
2328client dropping the connection is an error, which means this variant can
2329detect an unexpected detection close.
2330
2331To handle this case, always make sure you have a non-empty read queue, by
2332pushing the "read request start" handler on it:
2333
2334 # we assume a request starts with a single line
2335 my @start_request; @start_request = (line => sub {
2336 my ($hdl, $line) = @_;
2337
2338 ... handle request
2339
2340 # push next request read, possibly from a nested callback
2341 $hdl->push_read (@start_request);
2342 });
2343
2344 # auth done, now go into request handling loop
2345 # now push the first @start_request
2346 $hdl->push_read (@start_request);
2347
2348By always having an outstanding C<push_read>, the handle always expects
2349some data and raises the C<EPIPE> error when the connction is dropped
2350unexpectedly.
2351
2352The second variant is a protocol where the client can drop the connection
2353at any time. For TCP, this means that the server machine may run out of
2354sockets easier, and in general, it means you cannot distinguish a protocl
2355failure/client crash from a normal connection close. Nevertheless, these
2356kinds of protocols are common (and sometimes even the best solution to the
2357problem).
2358
2359Having an outstanding read request at all times is possible if you ignore
2360C<EPIPE> errors, but this doesn't help with when the client drops the
2361connection during a request, which would still be an error.
2362
2363A better solution is to push the initial request read in an C<on_read>
2364callback. This avoids an error, as when the server doesn't expect data
2365(i.e. is idly waiting for the next request, an EOF will not raise an
2366error, but simply result in an C<on_eof> callback. It is also a bit slower
2367and simpler:
2368
2369 # auth done, now go into request handling loop
2370 $hdl->on_read (sub {
2371 my ($hdl) = @_;
2372
2373 # called each time we receive data but the read queue is empty
2374 # simply start read the request
2375
2376 $hdl->push_read (line => sub {
2377 my ($hdl, $line) = @_;
2378
2379 ... handle request
2380
2381 # do nothing special when the request has been handled, just
2382 # let the request queue go empty.
2383 });
2384 });
2385
1582=item I get different callback invocations in TLS mode/Why can't I pause 2386=item I get different callback invocations in TLS mode/Why can't I pause
1583reading? 2387reading?
1584 2388
1585Unlike, say, TCP, TLS connections do not consist of two independent 2389Unlike, say, TCP, TLS connections do not consist of two independent
1586communication channels, one for each direction. Or put differently. The 2390communication channels, one for each direction. Or put differently, the
1587read and write directions are not independent of each other: you cannot 2391read and write directions are not independent of each other: you cannot
1588write data unless you are also prepared to read, and vice versa. 2392write data unless you are also prepared to read, and vice versa.
1589 2393
1590This can mean than, in TLS mode, you might get C<on_error> or C<on_eof> 2394This means that, in TLS mode, you might get C<on_error> or C<on_eof>
1591callback invocations when you are not expecting any read data - the reason 2395callback invocations when you are not expecting any read data - the reason
1592is that AnyEvent::Handle always reads in TLS mode. 2396is that AnyEvent::Handle always reads in TLS mode.
1593 2397
1594During the connection, you have to make sure that you always have a 2398During the connection, you have to make sure that you always have a
1595non-empty read-queue, or an C<on_read> watcher. At the end of the 2399non-empty read-queue, or an C<on_read> watcher. At the end of the
1605 2409
1606 $handle->on_read (sub { }); 2410 $handle->on_read (sub { });
1607 $handle->on_eof (undef); 2411 $handle->on_eof (undef);
1608 $handle->on_error (sub { 2412 $handle->on_error (sub {
1609 my $data = delete $_[0]{rbuf}; 2413 my $data = delete $_[0]{rbuf};
1610 undef $handle;
1611 }); 2414 });
2415
2416Note that this example removes the C<rbuf> member from the handle object,
2417which is not normally allowed by the API. It is expressly permitted in
2418this case only, as the handle object needs to be destroyed afterwards.
1612 2419
1613The reason to use C<on_error> is that TCP connections, due to latencies 2420The reason to use C<on_error> is that TCP connections, due to latencies
1614and packets loss, might get closed quite violently with an error, when in 2421and packets loss, might get closed quite violently with an error, when in
1615fact, all data has been received. 2422fact all data has been received.
1616 2423
1617It is usually better to use acknowledgements when transferring data, 2424It is usually better to use acknowledgements when transferring data,
1618to make sure the other side hasn't just died and you got the data 2425to make sure the other side hasn't just died and you got the data
1619intact. This is also one reason why so many internet protocols have an 2426intact. This is also one reason why so many internet protocols have an
1620explicit QUIT command. 2427explicit QUIT command.
1627C<low_water_mark> this will be called precisely when all data has been 2434C<low_water_mark> this will be called precisely when all data has been
1628written to the socket: 2435written to the socket:
1629 2436
1630 $handle->push_write (...); 2437 $handle->push_write (...);
1631 $handle->on_drain (sub { 2438 $handle->on_drain (sub {
1632 warn "all data submitted to the kernel\n"; 2439 AE::log debug => "All data submitted to the kernel.";
1633 undef $handle; 2440 undef $handle;
1634 }); 2441 });
1635 2442
2443If you just want to queue some data and then signal EOF to the other side,
2444consider using C<< ->push_shutdown >> instead.
2445
2446=item I want to contact a TLS/SSL server, I don't care about security.
2447
2448If your TLS server is a pure TLS server (e.g. HTTPS) that only speaks TLS,
2449connect to it and then create the AnyEvent::Handle with the C<tls>
2450parameter:
2451
2452 tcp_connect $host, $port, sub {
2453 my ($fh) = @_;
2454
2455 my $handle = new AnyEvent::Handle
2456 fh => $fh,
2457 tls => "connect",
2458 on_error => sub { ... };
2459
2460 $handle->push_write (...);
2461 };
2462
2463=item I want to contact a TLS/SSL server, I do care about security.
2464
2465Then you should additionally enable certificate verification, including
2466peername verification, if the protocol you use supports it (see
2467L<AnyEvent::TLS>, C<verify_peername>).
2468
2469E.g. for HTTPS:
2470
2471 tcp_connect $host, $port, sub {
2472 my ($fh) = @_;
2473
2474 my $handle = new AnyEvent::Handle
2475 fh => $fh,
2476 peername => $host,
2477 tls => "connect",
2478 tls_ctx => { verify => 1, verify_peername => "https" },
2479 ...
2480
2481Note that you must specify the hostname you connected to (or whatever
2482"peername" the protocol needs) as the C<peername> argument, otherwise no
2483peername verification will be done.
2484
2485The above will use the system-dependent default set of trusted CA
2486certificates. If you want to check against a specific CA, add the
2487C<ca_file> (or C<ca_cert>) arguments to C<tls_ctx>:
2488
2489 tls_ctx => {
2490 verify => 1,
2491 verify_peername => "https",
2492 ca_file => "my-ca-cert.pem",
2493 },
2494
2495=item I want to create a TLS/SSL server, how do I do that?
2496
2497Well, you first need to get a server certificate and key. You have
2498three options: a) ask a CA (buy one, use cacert.org etc.) b) create a
2499self-signed certificate (cheap. check the search engine of your choice,
2500there are many tutorials on the net) or c) make your own CA (tinyca2 is a
2501nice program for that purpose).
2502
2503Then create a file with your private key (in PEM format, see
2504L<AnyEvent::TLS>), followed by the certificate (also in PEM format). The
2505file should then look like this:
2506
2507 -----BEGIN RSA PRIVATE KEY-----
2508 ...header data
2509 ... lots of base64'y-stuff
2510 -----END RSA PRIVATE KEY-----
2511
2512 -----BEGIN CERTIFICATE-----
2513 ... lots of base64'y-stuff
2514 -----END CERTIFICATE-----
2515
2516The important bits are the "PRIVATE KEY" and "CERTIFICATE" parts. Then
2517specify this file as C<cert_file>:
2518
2519 tcp_server undef, $port, sub {
2520 my ($fh) = @_;
2521
2522 my $handle = new AnyEvent::Handle
2523 fh => $fh,
2524 tls => "accept",
2525 tls_ctx => { cert_file => "my-server-keycert.pem" },
2526 ...
2527
2528When you have intermediate CA certificates that your clients might not
2529know about, just append them to the C<cert_file>.
2530
1636=back 2531=back
1637
1638 2532
1639=head1 SUBCLASSING AnyEvent::Handle 2533=head1 SUBCLASSING AnyEvent::Handle
1640 2534
1641In many cases, you might want to subclass AnyEvent::Handle. 2535In many cases, you might want to subclass AnyEvent::Handle.
1642 2536
1659 2553
1660=item * all members not documented here and not prefixed with an underscore 2554=item * all members not documented here and not prefixed with an underscore
1661are free to use in subclasses. 2555are free to use in subclasses.
1662 2556
1663Of course, new versions of AnyEvent::Handle may introduce more "public" 2557Of course, new versions of AnyEvent::Handle may introduce more "public"
1664member variables, but thats just life, at least it is documented. 2558member variables, but that's just life. At least it is documented.
1665 2559
1666=back 2560=back
1667 2561
1668=head1 AUTHOR 2562=head1 AUTHOR
1669 2563
1670Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>. 2564Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>.
1671 2565
1672=cut 2566=cut
1673 2567
16741; # End of AnyEvent::Handle 25681
2569

Diff Legend

Removed lines
+ Added lines
< Changed lines
> Changed lines