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Revision 1.223 by root, Thu Sep 1 04:07:18 2011 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 = 4.82;
20 4
21=head1 SYNOPSIS 5=head1 SYNOPSIS
22 6
23 use AnyEvent; 7 use AnyEvent;
24 use AnyEvent::Handle; 8 use AnyEvent::Handle;
27 11
28 my $hdl; $hdl = new AnyEvent::Handle 12 my $hdl; $hdl = new AnyEvent::Handle
29 fh => \*STDIN, 13 fh => \*STDIN,
30 on_error => sub { 14 on_error => sub {
31 my ($hdl, $fatal, $msg) = @_; 15 my ($hdl, $fatal, $msg) = @_;
32 warn "got error $msg\n"; 16 AE::log warn => "got error $msg\n";
33 $hdl->destroy; 17 $hdl->destroy;
34 $cv->send; 18 $cv->send;
35 ); 19 };
36 20
37 # send some request line 21 # send some request line
38 $hdl->push_write ("getinfo\015\012"); 22 $hdl->push_write ("getinfo\015\012");
39 23
40 # read the response line 24 # read the response line
41 $hdl->push_read (line => sub { 25 $hdl->push_read (line => sub {
42 my ($hdl, $line) = @_; 26 my ($hdl, $line) = @_;
43 warn "got line <$line>\n"; 27 AE::log warn => "got line <$line>\n";
44 $cv->send; 28 $cv->send;
45 }); 29 });
46 30
47 $cv->recv; 31 $cv->recv;
48 32
49=head1 DESCRIPTION 33=head1 DESCRIPTION
50 34
51This 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
52filehandles. For utility functions for doing non-blocking connects and accepts 36stream-based filehandles (sockets, pipes, and other stream things).
53on sockets see L<AnyEvent::Util>.
54 37
55The L<AnyEvent::Intro> tutorial contains some well-documented 38The L<AnyEvent::Intro> tutorial contains some well-documented
56AnyEvent::Handle examples. 39AnyEvent::Handle examples.
57 40
58In the following, when the documentation refers to of "bytes" then this 41In the following, where the documentation refers to "bytes", it means
59means characters. As sysread and syswrite are used for all I/O, their 42characters. As sysread and syswrite are used for all I/O, their
60treatment 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.
61 47
62All callbacks will be invoked with the handle object as their first 48All callbacks will be invoked with the handle object as their first
63argument. 49argument.
64 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
65=head1 METHODS 82=head1 METHODS
66 83
67=over 4 84=over 4
68 85
69=item $handle = B<new> AnyEvent::TLS fh => $filehandle, key => value... 86=item $handle = B<new> AnyEvent::Handle fh => $filehandle, key => value...
70 87
71The constructor supports these arguments (all as C<< key => value >> pairs). 88The constructor supports these arguments (all as C<< key => value >> pairs).
72 89
73=over 4 90=over 4
74 91
75=item fh => $filehandle [MANDATORY] 92=item fh => $filehandle [C<fh> or C<connect> MANDATORY]
76 93
77The filehandle this L<AnyEvent::Handle> object will operate on. 94The filehandle this L<AnyEvent::Handle> object will operate on.
78
79NOTE: The filehandle will be set to non-blocking mode (using 95NOTE: The filehandle will be set to non-blocking mode (using
80C<AnyEvent::Util::fh_nonblocking>) by the constructor and needs to stay in 96C<AnyEvent::Util::fh_nonblocking>) by the constructor and needs to stay in
81that mode. 97that mode.
98
99=item connect => [$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, $retry->())
129
130This callback is called when a connection has been successfully established.
131
132The peer's numeric host and port (the socket peername) are passed as
133parameters, together with a retry callback.
134
135If, for some reason, the handle is not acceptable, calling C<$retry>
136will continue with the next connection target (in case of multi-homed
137hosts or SRV records there can be multiple connection endpoints). At the
138time it is called the read and write queues, eof status, tls status and
139similar properties of the handle will have been reset.
140
141In most cases, you should ignore the C<$retry> parameter.
142
143=item on_connect_error => $cb->($handle, $message)
144
145This callback is called when the connection could not be
146established. C<$!> will contain the relevant error code, and C<$message> a
147message describing it (usually the same as C<"$!">).
148
149If this callback isn't specified, then C<on_error> will be called with a
150fatal error instead.
151
152=back
153
154=item on_error => $cb->($handle, $fatal, $message)
155
156This is the error callback, which is called when, well, some error
157occured, such as not being able to resolve the hostname, failure to
158connect, or a read error.
159
160Some errors are fatal (which is indicated by C<$fatal> being true). On
161fatal errors the handle object will be destroyed (by a call to C<< ->
162destroy >>) after invoking the error callback (which means you are free to
163examine the handle object). Examples of fatal errors are an EOF condition
164with active (but unsatisfiable) read watchers (C<EPIPE>) or I/O errors. In
165cases where the other side can close the connection at will, it is
166often easiest to not report C<EPIPE> errors in this callback.
167
168AnyEvent::Handle tries to find an appropriate error code for you to check
169against, but in some cases (TLS errors), this does not work well. It is
170recommended to always output the C<$message> argument in human-readable
171error messages (it's usually the same as C<"$!">).
172
173Non-fatal errors can be retried by returning, but it is recommended
174to simply ignore this parameter and instead abondon the handle object
175when this callback is invoked. Examples of non-fatal errors are timeouts
176C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>).
177
178On entry to the callback, the value of C<$!> contains the operating
179system error code (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT>, C<EBADMSG> or
180C<EPROTO>).
181
182While not mandatory, it is I<highly> recommended to set this callback, as
183you will not be notified of errors otherwise. The default just calls
184C<croak>.
185
186=item on_read => $cb->($handle)
187
188This sets the default read callback, which is called when data arrives
189and no read request is in the queue (unlike read queue callbacks, this
190callback will only be called when at least one octet of data is in the
191read buffer).
192
193To access (and remove data from) the read buffer, use the C<< ->rbuf >>
194method or access the C<< $handle->{rbuf} >> member directly. Note that you
195must not enlarge or modify the read buffer, you can only remove data at
196the beginning from it.
197
198You can also call C<< ->push_read (...) >> or any other function that
199modifies the read queue. Or do both. Or ...
200
201When an EOF condition is detected, AnyEvent::Handle will first try to
202feed all the remaining data to the queued callbacks and C<on_read> before
203calling the C<on_eof> callback. If no progress can be made, then a fatal
204error will be raised (with C<$!> set to C<EPIPE>).
205
206Note that, unlike requests in the read queue, an C<on_read> callback
207doesn't mean you I<require> some data: if there is an EOF and there
208are outstanding read requests then an error will be flagged. With an
209C<on_read> callback, the C<on_eof> callback will be invoked.
82 210
83=item on_eof => $cb->($handle) 211=item on_eof => $cb->($handle)
84 212
85Set the callback to be called when an end-of-file condition is detected, 213Set the callback to be called when an end-of-file condition is detected,
86i.e. in the case of a socket, when the other side has closed the 214i.e. in the case of a socket, when the other side has closed the
94down. 222down.
95 223
96If an EOF condition has been detected but no C<on_eof> callback has been 224If an EOF condition has been detected but no C<on_eof> callback has been
97set, then a fatal error will be raised with C<$!> set to <0>. 225set, then a fatal error will be raised with C<$!> set to <0>.
98 226
99=item on_error => $cb->($handle, $fatal, $message)
100
101This is the error callback, which is called when, well, some error
102occured, such as not being able to resolve the hostname, failure to
103connect or a read error.
104
105Some errors are fatal (which is indicated by C<$fatal> being true). On
106fatal errors the handle object will be destroyed (by a call to C<< ->
107destroy >>) after invoking the error callback (which means you are free to
108examine the handle object). Examples of fatal errors are an EOF condition
109with active (but unsatisifable) read watchers (C<EPIPE>) or I/O errors.
110
111AnyEvent::Handle tries to find an appropriate error code for you to check
112against, but in some cases (TLS errors), this does not work well. It is
113recommended to always output the C<$message> argument in human-readable
114error messages (it's usually the same as C<"$!">).
115
116Non-fatal errors can be retried by simply returning, but it is recommended
117to simply ignore this parameter and instead abondon the handle object
118when this callback is invoked. Examples of non-fatal errors are timeouts
119C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>).
120
121On callback entrance, the value of C<$!> contains the operating system
122error code (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT>, C<EBADMSG> or
123C<EPROTO>).
124
125While not mandatory, it is I<highly> recommended to set this callback, as
126you will not be notified of errors otherwise. The default simply calls
127C<croak>.
128
129=item on_read => $cb->($handle)
130
131This sets the default read callback, which is called when data arrives
132and no read request is in the queue (unlike read queue callbacks, this
133callback will only be called when at least one octet of data is in the
134read buffer).
135
136To access (and remove data from) the read buffer, use the C<< ->rbuf >>
137method or access the C<< $handle->{rbuf} >> member directly. Note that you
138must not enlarge or modify the read buffer, you can only remove data at
139the beginning from it.
140
141When an EOF condition is detected then AnyEvent::Handle will first try to
142feed all the remaining data to the queued callbacks and C<on_read> before
143calling the C<on_eof> callback. If no progress can be made, then a fatal
144error will be raised (with C<$!> set to C<EPIPE>).
145
146Note that, unlike requests in the read queue, an C<on_read> callback
147doesn't mean you I<require> some data: if there is an EOF and there
148are outstanding read requests then an error will be flagged. With an
149C<on_read> callback, the C<on_eof> callback will be invoked.
150
151=item on_drain => $cb->($handle) 227=item on_drain => $cb->($handle)
152 228
153This sets the callback that is called when the write buffer becomes empty 229This sets the callback that is called when the write buffer becomes empty
154(or when the callback is set and the buffer is empty already). 230(or immediately if the buffer is empty already).
155 231
156To append to the write buffer, use the C<< ->push_write >> method. 232To append to the write buffer, use the C<< ->push_write >> method.
157 233
158This callback is useful when you don't want to put all of your write data 234This callback is useful when you don't want to put all of your write data
159into the queue at once, for example, when you want to write the contents 235into the queue at once, for example, when you want to write the contents
161memory and push it into the queue, but instead only read more data from 237memory and push it into the queue, but instead only read more data from
162the file when the write queue becomes empty. 238the file when the write queue becomes empty.
163 239
164=item timeout => $fractional_seconds 240=item timeout => $fractional_seconds
165 241
242=item rtimeout => $fractional_seconds
243
244=item wtimeout => $fractional_seconds
245
166If non-zero, then this enables an "inactivity" timeout: whenever this many 246If non-zero, then these enables an "inactivity" timeout: whenever this
167seconds pass without a successful read or write on the underlying file 247many seconds pass without a successful read or write on the underlying
168handle, the C<on_timeout> callback will be invoked (and if that one is 248file handle (or a call to C<timeout_reset>), the C<on_timeout> callback
169missing, a non-fatal C<ETIMEDOUT> error will be raised). 249will be invoked (and if that one is missing, a non-fatal C<ETIMEDOUT>
250error will be raised).
170 251
252There are three variants of the timeouts that work independently of each
253other, for both read and write (triggered when nothing was read I<OR>
254written), just read (triggered when nothing was read), and just write:
255C<timeout>, C<rtimeout> and C<wtimeout>, with corresponding callbacks
256C<on_timeout>, C<on_rtimeout> and C<on_wtimeout>, and reset functions
257C<timeout_reset>, C<rtimeout_reset>, and C<wtimeout_reset>.
258
171Note that timeout processing is also active when you currently do not have 259Note that timeout processing is active even when you do not have any
172any outstanding read or write requests: If you plan to keep the connection 260outstanding read or write requests: If you plan to keep the connection
173idle then you should disable the timout temporarily or ignore the timeout 261idle then you should disable the timeout temporarily or ignore the
174in the C<on_timeout> callback, in which case AnyEvent::Handle will simply 262timeout in the corresponding C<on_timeout> callback, in which case
175restart the timeout. 263AnyEvent::Handle will simply restart the timeout.
176 264
177Zero (the default) disables this timeout. 265Zero (the default) disables the corresponding timeout.
178 266
179=item on_timeout => $cb->($handle) 267=item on_timeout => $cb->($handle)
268
269=item on_rtimeout => $cb->($handle)
270
271=item on_wtimeout => $cb->($handle)
180 272
181Called whenever the inactivity timeout passes. If you return from this 273Called whenever the inactivity timeout passes. If you return from this
182callback, then the timeout will be reset as if some activity had happened, 274callback, then the timeout will be reset as if some activity had happened,
183so this condition is not fatal in any way. 275so this condition is not fatal in any way.
184 276
192be configured to accept only so-and-so much data that it cannot act on 284be configured to accept only so-and-so much data that it cannot act on
193(for example, when expecting a line, an attacker could send an unlimited 285(for example, when expecting a line, an attacker could send an unlimited
194amount of data without a callback ever being called as long as the line 286amount of data without a callback ever being called as long as the line
195isn't finished). 287isn't finished).
196 288
289=item wbuf_max => <bytes>
290
291If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)
292when the write buffer ever (strictly) exceeds this size. This is useful to
293avoid some forms of denial-of-service attacks.
294
295Although the units of this parameter is bytes, this is the I<raw> number
296of bytes not yet accepted by the kernel. This can make a difference when
297you e.g. use TLS, as TLS typically makes your write data larger (but it
298can also make it smaller due to compression).
299
300As an example of when this limit is useful, take a chat server that sends
301chat messages to a client. If the client does not read those in a timely
302manner then the send buffer in the server would grow unbounded.
303
197=item autocork => <boolean> 304=item autocork => <boolean>
198 305
199When disabled (the default), then C<push_write> will try to immediately 306When disabled (the default), C<push_write> will try to immediately
200write the data to the handle, if possible. This avoids having to register 307write the data to the handle if possible. This avoids having to register
201a write watcher and wait for the next event loop iteration, but can 308a write watcher and wait for the next event loop iteration, but can
202be inefficient if you write multiple small chunks (on the wire, this 309be inefficient if you write multiple small chunks (on the wire, this
203disadvantage is usually avoided by your kernel's nagle algorithm, see 310disadvantage is usually avoided by your kernel's nagle algorithm, see
204C<no_delay>, but this option can save costly syscalls). 311C<no_delay>, but this option can save costly syscalls).
205 312
206When enabled, then writes will always be queued till the next event loop 313When enabled, writes will always be queued till the next event loop
207iteration. This is efficient when you do many small writes per iteration, 314iteration. This is efficient when you do many small writes per iteration,
208but less efficient when you do a single write only per iteration (or when 315but less efficient when you do a single write only per iteration (or when
209the write buffer often is full). It also increases write latency. 316the write buffer often is full). It also increases write latency.
210 317
211=item no_delay => <boolean> 318=item no_delay => <boolean>
215the Nagle algorithm, and usually it is beneficial. 322the Nagle algorithm, and usually it is beneficial.
216 323
217In some situations you want as low a delay as possible, which can be 324In some situations you want as low a delay as possible, which can be
218accomplishd by setting this option to a true value. 325accomplishd by setting this option to a true value.
219 326
220The default is your opertaing system's default behaviour (most likely 327The default is your operating system's default behaviour (most likely
221enabled), this option explicitly enables or disables it, if possible. 328enabled). This option explicitly enables or disables it, if possible.
329
330=item keepalive => <boolean>
331
332Enables (default disable) the SO_KEEPALIVE option on the stream socket:
333normally, TCP connections have no time-out once established, so TCP
334connections, once established, can stay alive forever even when the other
335side has long gone. TCP keepalives are a cheap way to take down long-lived
336TCP connections when the other side becomes unreachable. While the default
337is OS-dependent, TCP keepalives usually kick in after around two hours,
338and, if the other side doesn't reply, take down the TCP connection some 10
339to 15 minutes later.
340
341It is harmless to specify this option for file handles that do not support
342keepalives, and enabling it on connections that are potentially long-lived
343is usually a good idea.
344
345=item oobinline => <boolean>
346
347BSD majorly fucked up the implementation of TCP urgent data. The result
348is that almost no OS implements TCP according to the specs, and every OS
349implements it slightly differently.
350
351If you want to handle TCP urgent data, then setting this flag (the default
352is enabled) gives you the most portable way of getting urgent data, by
353putting it into the stream.
354
355Since BSD emulation of OOB data on top of TCP's urgent data can have
356security implications, AnyEvent::Handle sets this flag automatically
357unless explicitly specified. Note that setting this flag after
358establishing a connection I<may> be a bit too late (data loss could
359already have occured on BSD systems), but at least it will protect you
360from most attacks.
222 361
223=item read_size => <bytes> 362=item read_size => <bytes>
224 363
225The default read block size (the amount of bytes this module will 364The initial read block size, the number of bytes this module will try
226try to read during each loop iteration, which affects memory 365to read during each loop iteration. Each handle object will consume
227requirements). Default: C<8192>. 366at least this amount of memory for the read buffer as well, so when
367handling many connections watch out for memory requirements). See also
368C<max_read_size>. Default: C<2048>.
369
370=item max_read_size => <bytes>
371
372The maximum read buffer size used by the dynamic adjustment
373algorithm: Each time AnyEvent::Handle can read C<read_size> bytes in
374one go it will double C<read_size> up to the maximum given by this
375option. Default: C<131072> or C<read_size>, whichever is higher.
228 376
229=item low_water_mark => <bytes> 377=item low_water_mark => <bytes>
230 378
231Sets the amount of bytes (default: C<0>) that make up an "empty" write 379Sets the number of bytes (default: C<0>) that make up an "empty" write
232buffer: If the write reaches this size or gets even samller it is 380buffer: If the buffer reaches this size or gets even samller it is
233considered empty. 381considered empty.
234 382
235Sometimes it can be beneficial (for performance reasons) to add data to 383Sometimes it can be beneficial (for performance reasons) to add data to
236the write buffer before it is fully drained, but this is a rare case, as 384the write buffer before it is fully drained, but this is a rare case, as
237the operating system kernel usually buffers data as well, so the default 385the operating system kernel usually buffers data as well, so the default
238is good in almost all cases. 386is good in almost all cases.
239 387
240=item linger => <seconds> 388=item linger => <seconds>
241 389
242If non-zero (default: C<3600>), then the destructor of the 390If this is non-zero (default: C<3600>), the destructor of the
243AnyEvent::Handle object will check whether there is still outstanding 391AnyEvent::Handle object will check whether there is still outstanding
244write data and will install a watcher that will write this data to the 392write data and will install a watcher that will write this data to the
245socket. No errors will be reported (this mostly matches how the operating 393socket. No errors will be reported (this mostly matches how the operating
246system treats outstanding data at socket close time). 394system treats outstanding data at socket close time).
247 395
254A string used to identify the remote site - usually the DNS hostname 402A string used to identify the remote site - usually the DNS hostname
255(I<not> IDN!) used to create the connection, rarely the IP address. 403(I<not> IDN!) used to create the connection, rarely the IP address.
256 404
257Apart from being useful in error messages, this string is also used in TLS 405Apart from being useful in error messages, this string is also used in TLS
258peername verification (see C<verify_peername> in L<AnyEvent::TLS>). This 406peername verification (see C<verify_peername> in L<AnyEvent::TLS>). This
259verification will be skipped when C<peername> is not specified or 407verification will be skipped when C<peername> is not specified or is
260C<undef>. 408C<undef>.
261 409
262=item tls => "accept" | "connect" | Net::SSLeay::SSL object 410=item tls => "accept" | "connect" | Net::SSLeay::SSL object
263 411
264When this parameter is given, it enables TLS (SSL) mode, that means 412When this parameter is given, it enables TLS (SSL) mode, that means
265AnyEvent will start a TLS handshake as soon as the conenction has been 413AnyEvent will start a TLS handshake as soon as the connection has been
266established and will transparently encrypt/decrypt data afterwards. 414established and will transparently encrypt/decrypt data afterwards.
267 415
268All TLS protocol errors will be signalled as C<EPROTO>, with an 416All TLS protocol errors will be signalled as C<EPROTO>, with an
269appropriate error message. 417appropriate error message.
270 418
290B<IMPORTANT:> since Net::SSLeay "objects" are really only integers, 438B<IMPORTANT:> since Net::SSLeay "objects" are really only integers,
291passing in the wrong integer will lead to certain crash. This most often 439passing in the wrong integer will lead to certain crash. This most often
292happens when one uses a stylish C<< tls => 1 >> and is surprised about the 440happens when one uses a stylish C<< tls => 1 >> and is surprised about the
293segmentation fault. 441segmentation fault.
294 442
295See the C<< ->starttls >> method for when need to start TLS negotiation later. 443Use the C<< ->starttls >> method if you need to start TLS negotiation later.
296 444
297=item tls_ctx => $anyevent_tls 445=item tls_ctx => $anyevent_tls
298 446
299Use the given C<AnyEvent::TLS> object to create the new TLS connection 447Use the given C<AnyEvent::TLS> object to create the new TLS connection
300(unless a connection object was specified directly). If this parameter is 448(unless a connection object was specified directly). If this
301missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>. 449parameter is missing (or C<undef>), then AnyEvent::Handle will use
450C<AnyEvent::Handle::TLS_CTX>.
302 451
303Instead of an object, you can also specify a hash reference with C<< key 452Instead of an object, you can also specify a hash reference with C<< key
304=> value >> pairs. Those will be passed to L<AnyEvent::TLS> to create a 453=> value >> pairs. Those will be passed to L<AnyEvent::TLS> to create a
305new TLS context object. 454new TLS context object.
306 455
315 464
316TLS handshake failures will not cause C<on_error> to be invoked when this 465TLS handshake failures will not cause C<on_error> to be invoked when this
317callback is in effect, instead, the error message will be passed to C<on_starttls>. 466callback is in effect, instead, the error message will be passed to C<on_starttls>.
318 467
319Without this callback, handshake failures lead to C<on_error> being 468Without this callback, handshake failures lead to C<on_error> being
320called, as normal. 469called as usual.
321 470
322Note that you cannot call C<starttls> right again in this callback. If you 471Note that you cannot just call C<starttls> again in this callback. If you
323need to do that, start an zero-second timer instead whose callback can 472need to do that, start an zero-second timer instead whose callback can
324then call C<< ->starttls >> again. 473then call C<< ->starttls >> again.
325 474
326=item on_stoptls => $cb->($handle) 475=item on_stoptls => $cb->($handle)
327 476
353 502
354sub new { 503sub new {
355 my $class = shift; 504 my $class = shift;
356 my $self = bless { @_ }, $class; 505 my $self = bless { @_ }, $class;
357 506
358 $self->{fh} or Carp::croak "mandatory argument fh is missing"; 507 if ($self->{fh}) {
508 $self->_start;
509 return unless $self->{fh}; # could be gone by now
510
511 } elsif ($self->{connect}) {
512 require AnyEvent::Socket;
513
514 $self->{peername} = $self->{connect}[0]
515 unless exists $self->{peername};
516
517 $self->{_skip_drain_rbuf} = 1;
518
519 {
520 Scalar::Util::weaken (my $self = $self);
521
522 $self->{_connect} =
523 AnyEvent::Socket::tcp_connect (
524 $self->{connect}[0],
525 $self->{connect}[1],
526 sub {
527 my ($fh, $host, $port, $retry) = @_;
528
529 delete $self->{_connect}; # no longer needed
530
531 if ($fh) {
532 $self->{fh} = $fh;
533
534 delete $self->{_skip_drain_rbuf};
535 $self->_start;
536
537 $self->{on_connect}
538 and $self->{on_connect}($self, $host, $port, sub {
539 delete @$self{qw(fh _tw _rtw _wtw _ww _rw _eof _queue rbuf _wbuf tls _tls_rbuf _tls_wbuf)};
540 $self->{_skip_drain_rbuf} = 1;
541 &$retry;
542 });
543
544 } else {
545 if ($self->{on_connect_error}) {
546 $self->{on_connect_error}($self, "$!");
547 $self->destroy if $self;
548 } else {
549 $self->_error ($!, 1);
550 }
551 }
552 },
553 sub {
554 local $self->{fh} = $_[0];
555
556 $self->{on_prepare}
557 ? $self->{on_prepare}->($self)
558 : ()
559 }
560 );
561 }
562
563 } else {
564 Carp::croak "AnyEvent::Handle: either an existing fh or the connect parameter must be specified";
565 }
566
567 $self
568}
569
570sub _start {
571 my ($self) = @_;
572
573 # too many clueless people try to use udp and similar sockets
574 # with AnyEvent::Handle, do them a favour.
575 my $type = getsockopt $self->{fh}, Socket::SOL_SOCKET (), Socket::SO_TYPE ();
576 Carp::croak "AnyEvent::Handle: only stream sockets supported, anything else will NOT work!"
577 if Socket::SOCK_STREAM () != (unpack "I", $type) && defined $type;
359 578
360 AnyEvent::Util::fh_nonblocking $self->{fh}, 1; 579 AnyEvent::Util::fh_nonblocking $self->{fh}, 1;
361 580
581 $self->{_activity} =
582 $self->{_ractivity} =
362 $self->{_activity} = AnyEvent->now; 583 $self->{_wactivity} = AE::now;
363 $self->_timeout;
364 584
585 $self->{read_size} ||= 2048;
586 $self->{max_read_size} = $self->{read_size}
587 if $self->{read_size} > ($self->{max_read_size} || MAX_READ_SIZE);
588
589 $self->timeout (delete $self->{timeout} ) if $self->{timeout};
590 $self->rtimeout (delete $self->{rtimeout} ) if $self->{rtimeout};
591 $self->wtimeout (delete $self->{wtimeout} ) if $self->{wtimeout};
592
365 $self->no_delay (delete $self->{no_delay}) if exists $self->{no_delay}; 593 $self->no_delay (delete $self->{no_delay} ) if exists $self->{no_delay} && $self->{no_delay};
594 $self->keepalive (delete $self->{keepalive}) if exists $self->{keepalive} && $self->{keepalive};
366 595
596 $self->oobinline (exists $self->{oobinline} ? delete $self->{oobinline} : 1);
597
367 $self->starttls (delete $self->{tls}, delete $self->{tls_ctx}) 598 $self->starttls (delete $self->{tls}, delete $self->{tls_ctx})
368 if $self->{tls}; 599 if $self->{tls};
369 600
370 $self->on_drain (delete $self->{on_drain}) if $self->{on_drain}; 601 $self->on_drain (delete $self->{on_drain} ) if $self->{on_drain};
371 602
372 $self->start_read 603 $self->start_read
373 if $self->{on_read}; 604 if $self->{on_read} || @{ $self->{_queue} };
374 605
375 $self->{fh} && $self 606 $self->_drain_wbuf;
376} 607}
377
378#sub _shutdown {
379# my ($self) = @_;
380#
381# delete @$self{qw(_tw _rw _ww fh wbuf on_read _queue)};
382# $self->{_eof} = 1; # tell starttls et. al to stop trying
383#
384# &_freetls;
385#}
386 608
387sub _error { 609sub _error {
388 my ($self, $errno, $fatal, $message) = @_; 610 my ($self, $errno, $fatal, $message) = @_;
389 611
390 $! = $errno; 612 $! = $errno;
391 $message ||= "$!"; 613 $message ||= "$!";
392 614
393 if ($self->{on_error}) { 615 if ($self->{on_error}) {
394 $self->{on_error}($self, $fatal, $message); 616 $self->{on_error}($self, $fatal, $message);
395 $self->destroy if $fatal; 617 $self->destroy if $fatal;
396 } elsif ($self->{fh}) { 618 } elsif ($self->{fh} || $self->{connect}) {
397 $self->destroy; 619 $self->destroy;
398 Carp::croak "AnyEvent::Handle uncaught error: $message"; 620 Carp::croak "AnyEvent::Handle uncaught error: $message";
399 } 621 }
400} 622}
401 623
427 $_[0]{on_eof} = $_[1]; 649 $_[0]{on_eof} = $_[1];
428} 650}
429 651
430=item $handle->on_timeout ($cb) 652=item $handle->on_timeout ($cb)
431 653
432Replace the current C<on_timeout> callback, or disables the callback (but 654=item $handle->on_rtimeout ($cb)
433not the timeout) if C<$cb> = C<undef>. See the C<timeout> constructor
434argument and method.
435 655
436=cut 656=item $handle->on_wtimeout ($cb)
437 657
438sub on_timeout { 658Replace the current C<on_timeout>, C<on_rtimeout> or C<on_wtimeout>
439 $_[0]{on_timeout} = $_[1]; 659callback, or disables the callback (but not the timeout) if C<$cb> =
440} 660C<undef>. See the C<timeout> constructor argument and method.
661
662=cut
663
664# see below
441 665
442=item $handle->autocork ($boolean) 666=item $handle->autocork ($boolean)
443 667
444Enables or disables the current autocork behaviour (see C<autocork> 668Enables or disables the current autocork behaviour (see C<autocork>
445constructor argument). Changes will only take effect on the next write. 669constructor argument). Changes will only take effect on the next write.
458=cut 682=cut
459 683
460sub no_delay { 684sub no_delay {
461 $_[0]{no_delay} = $_[1]; 685 $_[0]{no_delay} = $_[1];
462 686
687 setsockopt $_[0]{fh}, Socket::IPPROTO_TCP (), Socket::TCP_NODELAY (), int $_[1]
688 if $_[0]{fh};
689}
690
691=item $handle->keepalive ($boolean)
692
693Enables or disables the C<keepalive> setting (see constructor argument of
694the same name for details).
695
696=cut
697
698sub keepalive {
699 $_[0]{keepalive} = $_[1];
700
463 eval { 701 eval {
464 local $SIG{__DIE__}; 702 local $SIG{__DIE__};
465 setsockopt $_[0]{fh}, &Socket::IPPROTO_TCP, &Socket::TCP_NODELAY, int $_[1]; 703 setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_KEEPALIVE (), int $_[1]
704 if $_[0]{fh};
705 };
706}
707
708=item $handle->oobinline ($boolean)
709
710Enables or disables the C<oobinline> setting (see constructor argument of
711the same name for details).
712
713=cut
714
715sub oobinline {
716 $_[0]{oobinline} = $_[1];
717
718 eval {
719 local $SIG{__DIE__};
720 setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_OOBINLINE (), int $_[1]
721 if $_[0]{fh};
722 };
723}
724
725=item $handle->keepalive ($boolean)
726
727Enables or disables the C<keepalive> setting (see constructor argument of
728the same name for details).
729
730=cut
731
732sub keepalive {
733 $_[0]{keepalive} = $_[1];
734
735 eval {
736 local $SIG{__DIE__};
737 setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_KEEPALIVE (), int $_[1]
738 if $_[0]{fh};
466 }; 739 };
467} 740}
468 741
469=item $handle->on_starttls ($cb) 742=item $handle->on_starttls ($cb)
470 743
480 753
481Replace the current C<on_stoptls> callback (see the C<on_stoptls> constructor argument). 754Replace the current C<on_stoptls> callback (see the C<on_stoptls> constructor argument).
482 755
483=cut 756=cut
484 757
485sub on_starttls { 758sub on_stoptls {
486 $_[0]{on_stoptls} = $_[1]; 759 $_[0]{on_stoptls} = $_[1];
487} 760}
488 761
762=item $handle->rbuf_max ($max_octets)
763
764Configures the C<rbuf_max> setting (C<undef> disables it).
765
766=item $handle->wbuf_max ($max_octets)
767
768Configures the C<wbuf_max> setting (C<undef> disables it).
769
770=cut
771
772sub rbuf_max {
773 $_[0]{rbuf_max} = $_[1];
774}
775
776sub wbuf_max {
777 $_[0]{wbuf_max} = $_[1];
778}
779
489############################################################################# 780#############################################################################
490 781
491=item $handle->timeout ($seconds) 782=item $handle->timeout ($seconds)
492 783
784=item $handle->rtimeout ($seconds)
785
786=item $handle->wtimeout ($seconds)
787
493Configures (or disables) the inactivity timeout. 788Configures (or disables) the inactivity timeout.
494 789
495=cut 790The timeout will be checked instantly, so this method might destroy the
791handle before it returns.
496 792
497sub timeout { 793=item $handle->timeout_reset
794
795=item $handle->rtimeout_reset
796
797=item $handle->wtimeout_reset
798
799Reset the activity timeout, as if data was received or sent.
800
801These methods are cheap to call.
802
803=cut
804
805for my $dir ("", "r", "w") {
806 my $timeout = "${dir}timeout";
807 my $tw = "_${dir}tw";
808 my $on_timeout = "on_${dir}timeout";
809 my $activity = "_${dir}activity";
810 my $cb;
811
812 *$on_timeout = sub {
813 $_[0]{$on_timeout} = $_[1];
814 };
815
816 *$timeout = sub {
498 my ($self, $timeout) = @_; 817 my ($self, $new_value) = @_;
499 818
819 $new_value >= 0
820 or Carp::croak "AnyEvent::Handle->$timeout called with negative timeout ($new_value), caught";
821
500 $self->{timeout} = $timeout; 822 $self->{$timeout} = $new_value;
501 $self->_timeout; 823 delete $self->{$tw}; &$cb;
502} 824 };
503 825
826 *{"${dir}timeout_reset"} = sub {
827 $_[0]{$activity} = AE::now;
828 };
829
830 # main workhorse:
504# reset the timeout watcher, as neccessary 831 # reset the timeout watcher, as neccessary
505# also check for time-outs 832 # also check for time-outs
506sub _timeout { 833 $cb = sub {
507 my ($self) = @_; 834 my ($self) = @_;
508 835
509 if ($self->{timeout}) { 836 if ($self->{$timeout} && $self->{fh}) {
510 my $NOW = AnyEvent->now; 837 my $NOW = AE::now;
511 838
512 # when would the timeout trigger? 839 # when would the timeout trigger?
513 my $after = $self->{_activity} + $self->{timeout} - $NOW; 840 my $after = $self->{$activity} + $self->{$timeout} - $NOW;
514 841
515 # now or in the past already? 842 # now or in the past already?
516 if ($after <= 0) { 843 if ($after <= 0) {
517 $self->{_activity} = $NOW; 844 $self->{$activity} = $NOW;
518 845
519 if ($self->{on_timeout}) { 846 if ($self->{$on_timeout}) {
520 $self->{on_timeout}($self); 847 $self->{$on_timeout}($self);
521 } else { 848 } else {
522 $self->_error (Errno::ETIMEDOUT); 849 $self->_error (Errno::ETIMEDOUT);
850 }
851
852 # callback could have changed timeout value, optimise
853 return unless $self->{$timeout};
854
855 # calculate new after
856 $after = $self->{$timeout};
523 } 857 }
524 858
525 # callback could have changed timeout value, optimise 859 Scalar::Util::weaken $self;
526 return unless $self->{timeout}; 860 return unless $self; # ->error could have destroyed $self
527 861
528 # calculate new after 862 $self->{$tw} ||= AE::timer $after, 0, sub {
529 $after = $self->{timeout}; 863 delete $self->{$tw};
864 $cb->($self);
865 };
866 } else {
867 delete $self->{$tw};
530 } 868 }
531
532 Scalar::Util::weaken $self;
533 return unless $self; # ->error could have destroyed $self
534
535 $self->{_tw} ||= AnyEvent->timer (after => $after, cb => sub {
536 delete $self->{_tw};
537 $self->_timeout;
538 });
539 } else {
540 delete $self->{_tw};
541 } 869 }
542} 870}
543 871
544############################################################################# 872#############################################################################
545 873
561=item $handle->on_drain ($cb) 889=item $handle->on_drain ($cb)
562 890
563Sets the C<on_drain> callback or clears it (see the description of 891Sets the C<on_drain> callback or clears it (see the description of
564C<on_drain> in the constructor). 892C<on_drain> in the constructor).
565 893
894This method may invoke callbacks (and therefore the handle might be
895destroyed after it returns).
896
566=cut 897=cut
567 898
568sub on_drain { 899sub on_drain {
569 my ($self, $cb) = @_; 900 my ($self, $cb) = @_;
570 901
574 if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf}); 905 if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf});
575} 906}
576 907
577=item $handle->push_write ($data) 908=item $handle->push_write ($data)
578 909
579Queues the given scalar to be written. You can push as much data as you 910Queues the given scalar to be written. You can push as much data as
580want (only limited by the available memory), as C<AnyEvent::Handle> 911you want (only limited by the available memory and C<wbuf_max>), as
581buffers it independently of the kernel. 912C<AnyEvent::Handle> buffers it independently of the kernel.
913
914This method may invoke callbacks (and therefore the handle might be
915destroyed after it returns).
582 916
583=cut 917=cut
584 918
585sub _drain_wbuf { 919sub _drain_wbuf {
586 my ($self) = @_; 920 my ($self) = @_;
593 my $len = syswrite $self->{fh}, $self->{wbuf}; 927 my $len = syswrite $self->{fh}, $self->{wbuf};
594 928
595 if (defined $len) { 929 if (defined $len) {
596 substr $self->{wbuf}, 0, $len, ""; 930 substr $self->{wbuf}, 0, $len, "";
597 931
598 $self->{_activity} = AnyEvent->now; 932 $self->{_activity} = $self->{_wactivity} = AE::now;
599 933
600 $self->{on_drain}($self) 934 $self->{on_drain}($self)
601 if $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf}) 935 if $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf})
602 && $self->{on_drain}; 936 && $self->{on_drain};
603 937
609 943
610 # try to write data immediately 944 # try to write data immediately
611 $cb->() unless $self->{autocork}; 945 $cb->() unless $self->{autocork};
612 946
613 # if still data left in wbuf, we need to poll 947 # if still data left in wbuf, we need to poll
614 $self->{_ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb) 948 $self->{_ww} = AE::io $self->{fh}, 1, $cb
615 if length $self->{wbuf}; 949 if length $self->{wbuf};
950
951 if (
952 defined $self->{wbuf_max}
953 && $self->{wbuf_max} < length $self->{wbuf}
954 ) {
955 $self->_error (Errno::ENOSPC, 1), return;
956 }
616 }; 957 };
617} 958}
618 959
619our %WH; 960our %WH;
620 961
962# deprecated
621sub register_write_type($$) { 963sub register_write_type($$) {
622 $WH{$_[0]} = $_[1]; 964 $WH{$_[0]} = $_[1];
623} 965}
624 966
625sub push_write { 967sub push_write {
626 my $self = shift; 968 my $self = shift;
627 969
628 if (@_ > 1) { 970 if (@_ > 1) {
629 my $type = shift; 971 my $type = shift;
630 972
973 @_ = ($WH{$type} ||= _load_func "$type\::anyevent_write_type"
631 @_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write") 974 or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::push_write")
632 ->($self, @_); 975 ->($self, @_);
633 } 976 }
634 977
978 # we downgrade here to avoid hard-to-track-down bugs,
979 # and diagnose the problem earlier and better.
980
635 if ($self->{tls}) { 981 if ($self->{tls}) {
636 $self->{_tls_wbuf} .= $_[0]; 982 utf8::downgrade $self->{_tls_wbuf} .= $_[0];
637 983 &_dotls ($self) if $self->{fh};
638 &_dotls ($self);
639 } else { 984 } else {
640 $self->{wbuf} .= $_[0]; 985 utf8::downgrade $self->{wbuf} .= $_[0];
641 $self->_drain_wbuf; 986 $self->_drain_wbuf if $self->{fh};
642 } 987 }
643} 988}
644 989
645=item $handle->push_write (type => @args) 990=item $handle->push_write (type => @args)
646 991
647Instead of formatting your data yourself, you can also let this module do 992Instead of formatting your data yourself, you can also let this module
648the job by specifying a type and type-specific arguments. 993do the job by specifying a type and type-specific arguments. You
994can also specify the (fully qualified) name of a package, in which
995case AnyEvent tries to load the package and then expects to find the
996C<anyevent_write_type> function inside (see "custom write types", below).
649 997
650Predefined types are (if you have ideas for additional types, feel free to 998Predefined types are (if you have ideas for additional types, feel free to
651drop by and tell us): 999drop by and tell us):
652 1000
653=over 4 1001=over 4
710Other languages could read single lines terminated by a newline and pass 1058Other languages could read single lines terminated by a newline and pass
711this line into their JSON decoder of choice. 1059this line into their JSON decoder of choice.
712 1060
713=cut 1061=cut
714 1062
1063sub json_coder() {
1064 eval { require JSON::XS; JSON::XS->new->utf8 }
1065 || do { require JSON; JSON->new->utf8 }
1066}
1067
715register_write_type json => sub { 1068register_write_type json => sub {
716 my ($self, $ref) = @_; 1069 my ($self, $ref) = @_;
717 1070
718 require JSON; 1071 my $json = $self->{json} ||= json_coder;
719 1072
720 $self->{json} ? $self->{json}->encode ($ref) 1073 $json->encode ($ref)
721 : JSON::encode_json ($ref)
722}; 1074};
723 1075
724=item storable => $reference 1076=item storable => $reference
725 1077
726Freezes the given reference using L<Storable> and writes it to the 1078Freezes the given reference using L<Storable> and writes it to the
744before it was actually written. One way to do that is to replace your 1096before it was actually written. One way to do that is to replace your
745C<on_drain> handler by a callback that shuts down the socket (and set 1097C<on_drain> handler by a callback that shuts down the socket (and set
746C<low_water_mark> to C<0>). This method is a shorthand for just that, and 1098C<low_water_mark> to C<0>). This method is a shorthand for just that, and
747replaces the C<on_drain> callback with: 1099replaces the C<on_drain> callback with:
748 1100
749 sub { shutdown $_[0]{fh}, 1 } # for push_shutdown 1101 sub { shutdown $_[0]{fh}, 1 }
750 1102
751This simply shuts down the write side and signals an EOF condition to the 1103This simply shuts down the write side and signals an EOF condition to the
752the peer. 1104the peer.
753 1105
754You can rely on the normal read queue and C<on_eof> handling 1106You can rely on the normal read queue and C<on_eof> handling
755afterwards. This is the cleanest way to close a connection. 1107afterwards. This is the cleanest way to close a connection.
756 1108
1109This method may invoke callbacks (and therefore the handle might be
1110destroyed after it returns).
1111
757=cut 1112=cut
758 1113
759sub push_shutdown { 1114sub push_shutdown {
760 my ($self) = @_; 1115 my ($self) = @_;
761 1116
762 delete $self->{low_water_mark}; 1117 delete $self->{low_water_mark};
763 $self->on_drain (sub { shutdown $_[0]{fh}, 1 }); 1118 $self->on_drain (sub { shutdown $_[0]{fh}, 1 });
764} 1119}
765 1120
766=item AnyEvent::Handle::register_write_type type => $coderef->($handle, @args) 1121=item custom write types - Package::anyevent_write_type $handle, @args
767 1122
768This function (not method) lets you add your own types to C<push_write>. 1123Instead of one of the predefined types, you can also specify the name of
1124a package. AnyEvent will try to load the package and then expects to find
1125a function named C<anyevent_write_type> inside. If it isn't found, it
1126progressively tries to load the parent package until it either finds the
1127function (good) or runs out of packages (bad).
1128
769Whenever the given C<type> is used, C<push_write> will invoke the code 1129Whenever the given C<type> is used, C<push_write> will the function with
770reference with the handle object and the remaining arguments. 1130the handle object and the remaining arguments.
771 1131
772The code reference is supposed to return a single octet string that will 1132The function is supposed to return a single octet string that will be
773be appended to the write buffer. 1133appended to the write buffer, so you can mentally treat this function as a
1134"arguments to on-the-wire-format" converter.
774 1135
775Note that this is a function, and all types registered this way will be 1136Example: implement a custom write type C<join> that joins the remaining
776global, so try to use unique names. 1137arguments using the first one.
1138
1139 $handle->push_write (My::Type => " ", 1,2,3);
1140
1141 # uses the following package, which can be defined in the "My::Type" or in
1142 # the "My" modules to be auto-loaded, or just about anywhere when the
1143 # My::Type::anyevent_write_type is defined before invoking it.
1144
1145 package My::Type;
1146
1147 sub anyevent_write_type {
1148 my ($handle, $delim, @args) = @_;
1149
1150 join $delim, @args
1151 }
777 1152
778=cut 1153=cut
779 1154
780############################################################################# 1155#############################################################################
781 1156
790ways, the "simple" way, using only C<on_read> and the "complex" way, using 1165ways, the "simple" way, using only C<on_read> and the "complex" way, using
791a queue. 1166a queue.
792 1167
793In the simple case, you just install an C<on_read> callback and whenever 1168In the simple case, you just install an C<on_read> callback and whenever
794new data arrives, it will be called. You can then remove some data (if 1169new data arrives, it will be called. You can then remove some data (if
795enough is there) from the read buffer (C<< $handle->rbuf >>). Or you cna 1170enough is there) from the read buffer (C<< $handle->rbuf >>). Or you can
796leave the data there if you want to accumulate more (e.g. when only a 1171leave the data there if you want to accumulate more (e.g. when only a
797partial message has been received so far). 1172partial message has been received so far), or change the read queue with
1173e.g. C<push_read>.
798 1174
799In the more complex case, you want to queue multiple callbacks. In this 1175In the more complex case, you want to queue multiple callbacks. In this
800case, AnyEvent::Handle will call the first queued callback each time new 1176case, AnyEvent::Handle will call the first queued callback each time new
801data arrives (also the first time it is queued) and removes it when it has 1177data arrives (also the first time it is queued) and remove it when it has
802done its job (see C<push_read>, below). 1178done its job (see C<push_read>, below).
803 1179
804This way you can, for example, push three line-reads, followed by reading 1180This way you can, for example, push three line-reads, followed by reading
805a chunk of data, and AnyEvent::Handle will execute them in order. 1181a chunk of data, and AnyEvent::Handle will execute them in order.
806 1182
863=cut 1239=cut
864 1240
865sub _drain_rbuf { 1241sub _drain_rbuf {
866 my ($self) = @_; 1242 my ($self) = @_;
867 1243
1244 # avoid recursion
1245 return if $self->{_skip_drain_rbuf};
868 local $self->{_in_drain} = 1; 1246 local $self->{_skip_drain_rbuf} = 1;
869
870 if (
871 defined $self->{rbuf_max}
872 && $self->{rbuf_max} < length $self->{rbuf}
873 ) {
874 $self->_error (Errno::ENOSPC, 1), return;
875 }
876 1247
877 while () { 1248 while () {
878 # we need to use a separate tls read buffer, as we must not receive data while 1249 # we need to use a separate tls read buffer, as we must not receive data while
879 # we are draining the buffer, and this can only happen with TLS. 1250 # we are draining the buffer, and this can only happen with TLS.
880 $self->{rbuf} .= delete $self->{_tls_rbuf} if exists $self->{_tls_rbuf}; 1251 $self->{rbuf} .= delete $self->{_tls_rbuf}
1252 if exists $self->{_tls_rbuf};
881 1253
882 my $len = length $self->{rbuf}; 1254 my $len = length $self->{rbuf};
883 1255
884 if (my $cb = shift @{ $self->{_queue} }) { 1256 if (my $cb = shift @{ $self->{_queue} }) {
885 unless ($cb->($self)) { 1257 unless ($cb->($self)) {
886 if ($self->{_eof}) { 1258 # no progress can be made
887 # no progress can be made (not enough data and no data forthcoming) 1259 # (not enough data and no data forthcoming)
888 $self->_error (Errno::EPIPE, 1), return; 1260 $self->_error (Errno::EPIPE, 1), return
889 } 1261 if $self->{_eof};
890 1262
891 unshift @{ $self->{_queue} }, $cb; 1263 unshift @{ $self->{_queue} }, $cb;
892 last; 1264 last;
893 } 1265 }
894 } elsif ($self->{on_read}) { 1266 } elsif ($self->{on_read}) {
914 last; 1286 last;
915 } 1287 }
916 } 1288 }
917 1289
918 if ($self->{_eof}) { 1290 if ($self->{_eof}) {
919 if ($self->{on_eof}) { 1291 $self->{on_eof}
920 $self->{on_eof}($self) 1292 ? $self->{on_eof}($self)
921 } else {
922 $self->_error (0, 1, "Unexpected end-of-file"); 1293 : $self->_error (0, 1, "Unexpected end-of-file");
923 } 1294
1295 return;
1296 }
1297
1298 if (
1299 defined $self->{rbuf_max}
1300 && $self->{rbuf_max} < length $self->{rbuf}
1301 ) {
1302 $self->_error (Errno::ENOSPC, 1), return;
924 } 1303 }
925 1304
926 # may need to restart read watcher 1305 # may need to restart read watcher
927 unless ($self->{_rw}) { 1306 unless ($self->{_rw}) {
928 $self->start_read 1307 $self->start_read
934 1313
935This replaces the currently set C<on_read> callback, or clears it (when 1314This replaces the currently set C<on_read> callback, or clears it (when
936the new callback is C<undef>). See the description of C<on_read> in the 1315the new callback is C<undef>). See the description of C<on_read> in the
937constructor. 1316constructor.
938 1317
1318This method may invoke callbacks (and therefore the handle might be
1319destroyed after it returns).
1320
939=cut 1321=cut
940 1322
941sub on_read { 1323sub on_read {
942 my ($self, $cb) = @_; 1324 my ($self, $cb) = @_;
943 1325
944 $self->{on_read} = $cb; 1326 $self->{on_read} = $cb;
945 $self->_drain_rbuf if $cb && !$self->{_in_drain}; 1327 $self->_drain_rbuf if $cb;
946} 1328}
947 1329
948=item $handle->rbuf 1330=item $handle->rbuf
949 1331
950Returns the read buffer (as a modifiable lvalue). 1332Returns the read buffer (as a modifiable lvalue). You can also access the
1333read buffer directly as the C<< ->{rbuf} >> member, if you want (this is
1334much faster, and no less clean).
951 1335
952You can access the read buffer directly as the C<< ->{rbuf} >> 1336The only operation allowed on the read buffer (apart from looking at it)
953member, if you want. However, the only operation allowed on the 1337is removing data from its beginning. Otherwise modifying or appending to
954read buffer (apart from looking at it) is removing data from its 1338it is not allowed and will lead to hard-to-track-down bugs.
955beginning. Otherwise modifying or appending to it is not allowed and will
956lead to hard-to-track-down bugs.
957 1339
958NOTE: The read buffer should only be used or modified if the C<on_read>, 1340NOTE: The read buffer should only be used or modified in the C<on_read>
959C<push_read> or C<unshift_read> methods are used. The other read methods 1341callback or when C<push_read> or C<unshift_read> are used with a single
960automatically manage the read buffer. 1342callback (i.e. untyped). Typed C<push_read> and C<unshift_read> methods
1343will manage the read buffer on their own.
961 1344
962=cut 1345=cut
963 1346
964sub rbuf : lvalue { 1347sub rbuf : lvalue {
965 $_[0]{rbuf} 1348 $_[0]{rbuf}
982 1365
983If enough data was available, then the callback must remove all data it is 1366If enough data was available, then the callback must remove all data it is
984interested in (which can be none at all) and return a true value. After returning 1367interested in (which can be none at all) and return a true value. After returning
985true, it will be removed from the queue. 1368true, it will be removed from the queue.
986 1369
1370These methods may invoke callbacks (and therefore the handle might be
1371destroyed after it returns).
1372
987=cut 1373=cut
988 1374
989our %RH; 1375our %RH;
990 1376
991sub register_read_type($$) { 1377sub register_read_type($$) {
997 my $cb = pop; 1383 my $cb = pop;
998 1384
999 if (@_) { 1385 if (@_) {
1000 my $type = shift; 1386 my $type = shift;
1001 1387
1388 $cb = ($RH{$type} ||= _load_func "$type\::anyevent_read_type"
1002 $cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_read") 1389 or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::push_read")
1003 ->($self, $cb, @_); 1390 ->($self, $cb, @_);
1004 } 1391 }
1005 1392
1006 push @{ $self->{_queue} }, $cb; 1393 push @{ $self->{_queue} }, $cb;
1007 $self->_drain_rbuf unless $self->{_in_drain}; 1394 $self->_drain_rbuf;
1008} 1395}
1009 1396
1010sub unshift_read { 1397sub unshift_read {
1011 my $self = shift; 1398 my $self = shift;
1012 my $cb = pop; 1399 my $cb = pop;
1013 1400
1014 if (@_) { 1401 if (@_) {
1015 my $type = shift; 1402 my $type = shift;
1016 1403
1404 $cb = ($RH{$type} ||= _load_func "$type\::anyevent_read_type"
1017 $cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::unshift_read") 1405 or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::unshift_read")
1018 ->($self, $cb, @_); 1406 ->($self, $cb, @_);
1019 } 1407 }
1020 1408
1021
1022 unshift @{ $self->{_queue} }, $cb; 1409 unshift @{ $self->{_queue} }, $cb;
1023 $self->_drain_rbuf unless $self->{_in_drain}; 1410 $self->_drain_rbuf;
1024} 1411}
1025 1412
1026=item $handle->push_read (type => @args, $cb) 1413=item $handle->push_read (type => @args, $cb)
1027 1414
1028=item $handle->unshift_read (type => @args, $cb) 1415=item $handle->unshift_read (type => @args, $cb)
1029 1416
1030Instead of providing a callback that parses the data itself you can chose 1417Instead of providing a callback that parses the data itself you can chose
1031between a number of predefined parsing formats, for chunks of data, lines 1418between a number of predefined parsing formats, for chunks of data, lines
1032etc. 1419etc. You can also specify the (fully qualified) name of a package, in
1420which case AnyEvent tries to load the package and then expects to find the
1421C<anyevent_read_type> function inside (see "custom read types", below).
1033 1422
1034Predefined types are (if you have ideas for additional types, feel free to 1423Predefined types are (if you have ideas for additional types, feel free to
1035drop by and tell us): 1424drop by and tell us):
1036 1425
1037=over 4 1426=over 4
1043data. 1432data.
1044 1433
1045Example: read 2 bytes. 1434Example: read 2 bytes.
1046 1435
1047 $handle->push_read (chunk => 2, sub { 1436 $handle->push_read (chunk => 2, sub {
1048 warn "yay ", unpack "H*", $_[1]; 1437 AE::log debug => "yay " . unpack "H*", $_[1];
1049 }); 1438 });
1050 1439
1051=cut 1440=cut
1052 1441
1053register_read_type chunk => sub { 1442register_read_type chunk => sub {
1129the receive buffer when neither C<$accept> nor C<$reject> match, 1518the receive buffer when neither C<$accept> nor C<$reject> match,
1130and everything preceding and including the match will be accepted 1519and everything preceding and including the match will be accepted
1131unconditionally. This is useful to skip large amounts of data that you 1520unconditionally. This is useful to skip large amounts of data that you
1132know cannot be matched, so that the C<$accept> or C<$reject> regex do not 1521know cannot be matched, so that the C<$accept> or C<$reject> regex do not
1133have to start matching from the beginning. This is purely an optimisation 1522have to start matching from the beginning. This is purely an optimisation
1134and is usually worth only when you expect more than a few kilobytes. 1523and is usually worth it only when you expect more than a few kilobytes.
1135 1524
1136Example: expect a http header, which ends at C<\015\012\015\012>. Since we 1525Example: expect a http header, which ends at C<\015\012\015\012>. Since we
1137expect the header to be very large (it isn't in practise, but...), we use 1526expect the header to be very large (it isn't in practice, but...), we use
1138a skip regex to skip initial portions. The skip regex is tricky in that 1527a skip regex to skip initial portions. The skip regex is tricky in that
1139it only accepts something not ending in either \015 or \012, as these are 1528it only accepts something not ending in either \015 or \012, as these are
1140required for the accept regex. 1529required for the accept regex.
1141 1530
1142 $handle->push_read (regex => 1531 $handle->push_read (regex =>
1155 1544
1156 sub { 1545 sub {
1157 # accept 1546 # accept
1158 if ($$rbuf =~ $accept) { 1547 if ($$rbuf =~ $accept) {
1159 $data .= substr $$rbuf, 0, $+[0], ""; 1548 $data .= substr $$rbuf, 0, $+[0], "";
1160 $cb->($self, $data); 1549 $cb->($_[0], $data);
1161 return 1; 1550 return 1;
1162 } 1551 }
1163 1552
1164 # reject 1553 # reject
1165 if ($reject && $$rbuf =~ $reject) { 1554 if ($reject && $$rbuf =~ $reject) {
1166 $self->_error (Errno::EBADMSG); 1555 $_[0]->_error (Errno::EBADMSG);
1167 } 1556 }
1168 1557
1169 # skip 1558 # skip
1170 if ($skip && $$rbuf =~ $skip) { 1559 if ($skip && $$rbuf =~ $skip) {
1171 $data .= substr $$rbuf, 0, $+[0], ""; 1560 $data .= substr $$rbuf, 0, $+[0], "";
1187 my ($self, $cb) = @_; 1576 my ($self, $cb) = @_;
1188 1577
1189 sub { 1578 sub {
1190 unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) { 1579 unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
1191 if ($_[0]{rbuf} =~ /[^0-9]/) { 1580 if ($_[0]{rbuf} =~ /[^0-9]/) {
1192 $self->_error (Errno::EBADMSG); 1581 $_[0]->_error (Errno::EBADMSG);
1193 } 1582 }
1194 return; 1583 return;
1195 } 1584 }
1196 1585
1197 my $len = $1; 1586 my $len = $1;
1198 1587
1199 $self->unshift_read (chunk => $len, sub { 1588 $_[0]->unshift_read (chunk => $len, sub {
1200 my $string = $_[1]; 1589 my $string = $_[1];
1201 $_[0]->unshift_read (chunk => 1, sub { 1590 $_[0]->unshift_read (chunk => 1, sub {
1202 if ($_[1] eq ",") { 1591 if ($_[1] eq ",") {
1203 $cb->($_[0], $string); 1592 $cb->($_[0], $string);
1204 } else { 1593 } else {
1205 $self->_error (Errno::EBADMSG); 1594 $_[0]->_error (Errno::EBADMSG);
1206 } 1595 }
1207 }); 1596 });
1208 }); 1597 });
1209 1598
1210 1 1599 1
1277=cut 1666=cut
1278 1667
1279register_read_type json => sub { 1668register_read_type json => sub {
1280 my ($self, $cb) = @_; 1669 my ($self, $cb) = @_;
1281 1670
1282 my $json = $self->{json} ||= 1671 my $json = $self->{json} ||= json_coder;
1283 eval { require JSON::XS; JSON::XS->new->utf8 }
1284 || do { require JSON; JSON->new->utf8 };
1285 1672
1286 my $data; 1673 my $data;
1287 my $rbuf = \$self->{rbuf}; 1674 my $rbuf = \$self->{rbuf};
1288 1675
1289 sub { 1676 sub {
1290 my $ref = eval { $json->incr_parse ($self->{rbuf}) }; 1677 my $ref = eval { $json->incr_parse ($_[0]{rbuf}) };
1291 1678
1292 if ($ref) { 1679 if ($ref) {
1293 $self->{rbuf} = $json->incr_text; 1680 $_[0]{rbuf} = $json->incr_text;
1294 $json->incr_text = ""; 1681 $json->incr_text = "";
1295 $cb->($self, $ref); 1682 $cb->($_[0], $ref);
1296 1683
1297 1 1684 1
1298 } elsif ($@) { 1685 } elsif ($@) {
1299 # error case 1686 # error case
1300 $json->incr_skip; 1687 $json->incr_skip;
1301 1688
1302 $self->{rbuf} = $json->incr_text; 1689 $_[0]{rbuf} = $json->incr_text;
1303 $json->incr_text = ""; 1690 $json->incr_text = "";
1304 1691
1305 $self->_error (Errno::EBADMSG); 1692 $_[0]->_error (Errno::EBADMSG);
1306 1693
1307 () 1694 ()
1308 } else { 1695 } else {
1309 $self->{rbuf} = ""; 1696 $_[0]{rbuf} = "";
1310 1697
1311 () 1698 ()
1312 } 1699 }
1313 } 1700 }
1314}; 1701};
1347 # read remaining chunk 1734 # read remaining chunk
1348 $_[0]->unshift_read (chunk => $len, sub { 1735 $_[0]->unshift_read (chunk => $len, sub {
1349 if (my $ref = eval { Storable::thaw ($_[1]) }) { 1736 if (my $ref = eval { Storable::thaw ($_[1]) }) {
1350 $cb->($_[0], $ref); 1737 $cb->($_[0], $ref);
1351 } else { 1738 } else {
1352 $self->_error (Errno::EBADMSG); 1739 $_[0]->_error (Errno::EBADMSG);
1353 } 1740 }
1354 }); 1741 });
1355 } 1742 }
1356 1743
1357 1 1744 1
1358 } 1745 }
1359}; 1746};
1360 1747
1361=back 1748=back
1362 1749
1363=item AnyEvent::Handle::register_read_type type => $coderef->($handle, $cb, @args) 1750=item custom read types - Package::anyevent_read_type $handle, $cb, @args
1364 1751
1365This function (not method) lets you add your own types to C<push_read>. 1752Instead of one of the predefined types, you can also specify the name
1753of a package. AnyEvent will try to load the package and then expects to
1754find a function named C<anyevent_read_type> inside. If it isn't found, it
1755progressively tries to load the parent package until it either finds the
1756function (good) or runs out of packages (bad).
1366 1757
1367Whenever the given C<type> is used, C<push_read> will invoke the code 1758Whenever this type is used, C<push_read> will invoke the function with the
1368reference with the handle object, the callback and the remaining 1759handle object, the original callback and the remaining arguments.
1369arguments.
1370 1760
1371The code reference is supposed to return a callback (usually a closure) 1761The function is supposed to return a callback (usually a closure) that
1372that works as a plain read callback (see C<< ->push_read ($cb) >>). 1762works as a plain read callback (see C<< ->push_read ($cb) >>), so you can
1763mentally treat the function as a "configurable read type to read callback"
1764converter.
1373 1765
1374It should invoke the passed callback when it is done reading (remember to 1766It should invoke the original callback when it is done reading (remember
1375pass C<$handle> as first argument as all other callbacks do that). 1767to pass C<$handle> as first argument as all other callbacks do that,
1768although there is no strict requirement on this).
1376 1769
1377Note that this is a function, and all types registered this way will be
1378global, so try to use unique names.
1379
1380For examples, see the source of this module (F<perldoc -m AnyEvent::Handle>, 1770For examples, see the source of this module (F<perldoc -m
1381search for C<register_read_type>)). 1771AnyEvent::Handle>, search for C<register_read_type>)).
1382 1772
1383=item $handle->stop_read 1773=item $handle->stop_read
1384 1774
1385=item $handle->start_read 1775=item $handle->start_read
1386 1776
1392Note that AnyEvent::Handle will automatically C<start_read> for you when 1782Note that AnyEvent::Handle will automatically C<start_read> for you when
1393you change the C<on_read> callback or push/unshift a read callback, and it 1783you change the C<on_read> callback or push/unshift a read callback, and it
1394will automatically C<stop_read> for you when neither C<on_read> is set nor 1784will automatically C<stop_read> for you when neither C<on_read> is set nor
1395there are any read requests in the queue. 1785there are any read requests in the queue.
1396 1786
1397These methods will have no effect when in TLS mode (as TLS doesn't support 1787In older versions of this module (<= 5.3), these methods had no effect,
1398half-duplex connections). 1788as TLS does not support half-duplex connections. In current versions they
1789work as expected, as this behaviour is required to avoid certain resource
1790attacks, where the program would be forced to read (and buffer) arbitrary
1791amounts of data before being able to send some data. The drawback is that
1792some readings of the the SSL/TLS specifications basically require this
1793attack to be working, as SSL/TLS implementations might stall sending data
1794during a rehandshake.
1795
1796As a guideline, during the initial handshake, you should not stop reading,
1797and as a client, it might cause problems, depending on your applciation.
1399 1798
1400=cut 1799=cut
1401 1800
1402sub stop_read { 1801sub stop_read {
1403 my ($self) = @_; 1802 my ($self) = @_;
1404 1803
1405 delete $self->{_rw} unless $self->{tls}; 1804 delete $self->{_rw};
1406} 1805}
1407 1806
1408sub start_read { 1807sub start_read {
1409 my ($self) = @_; 1808 my ($self) = @_;
1410 1809
1411 unless ($self->{_rw} || $self->{_eof}) { 1810 unless ($self->{_rw} || $self->{_eof} || !$self->{fh}) {
1412 Scalar::Util::weaken $self; 1811 Scalar::Util::weaken $self;
1413 1812
1414 $self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub { 1813 $self->{_rw} = AE::io $self->{fh}, 0, sub {
1415 my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf}); 1814 my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf});
1416 my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf; 1815 my $len = sysread $self->{fh}, $$rbuf, $self->{read_size}, length $$rbuf;
1417 1816
1418 if ($len > 0) { 1817 if ($len > 0) {
1419 $self->{_activity} = AnyEvent->now; 1818 $self->{_activity} = $self->{_ractivity} = AE::now;
1420 1819
1421 if ($self->{tls}) { 1820 if ($self->{tls}) {
1422 Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf); 1821 Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf);
1423 1822
1424 &_dotls ($self); 1823 &_dotls ($self);
1425 } else { 1824 } else {
1426 $self->_drain_rbuf unless $self->{_in_drain}; 1825 $self->_drain_rbuf;
1826 }
1827
1828 if ($len == $self->{read_size}) {
1829 $self->{read_size} *= 2;
1830 $self->{read_size} = $self->{max_read_size} || MAX_READ_SIZE
1831 if $self->{read_size} > ($self->{max_read_size} || MAX_READ_SIZE);
1427 } 1832 }
1428 1833
1429 } elsif (defined $len) { 1834 } elsif (defined $len) {
1430 delete $self->{_rw}; 1835 delete $self->{_rw};
1431 $self->{_eof} = 1; 1836 $self->{_eof} = 1;
1432 $self->_drain_rbuf unless $self->{_in_drain}; 1837 $self->_drain_rbuf;
1433 1838
1434 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) { 1839 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
1435 return $self->_error ($!, 1); 1840 return $self->_error ($!, 1);
1436 } 1841 }
1437 }); 1842 };
1438 } 1843 }
1439} 1844}
1440 1845
1441our $ERROR_SYSCALL; 1846our $ERROR_SYSCALL;
1442our $ERROR_WANT_READ; 1847our $ERROR_WANT_READ;
1497 $self->{_eof} = 1; 1902 $self->{_eof} = 1;
1498 } 1903 }
1499 } 1904 }
1500 1905
1501 $self->{_tls_rbuf} .= $tmp; 1906 $self->{_tls_rbuf} .= $tmp;
1502 $self->_drain_rbuf unless $self->{_in_drain}; 1907 $self->_drain_rbuf;
1503 $self->{tls} or return; # tls session might have gone away in callback 1908 $self->{tls} or return; # tls session might have gone away in callback
1504 } 1909 }
1505 1910
1506 $tmp = Net::SSLeay::get_error ($self->{tls}, -1); 1911 $tmp = Net::SSLeay::get_error ($self->{tls}, -1);
1507 return $self->_tls_error ($tmp) 1912 return $self->_tls_error ($tmp)
1509 && ($tmp != $ERROR_SYSCALL || $!); 1914 && ($tmp != $ERROR_SYSCALL || $!);
1510 1915
1511 while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) { 1916 while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) {
1512 $self->{wbuf} .= $tmp; 1917 $self->{wbuf} .= $tmp;
1513 $self->_drain_wbuf; 1918 $self->_drain_wbuf;
1919 $self->{tls} or return; # tls session might have gone away in callback
1514 } 1920 }
1515 1921
1516 $self->{_on_starttls} 1922 $self->{_on_starttls}
1517 and Net::SSLeay::state ($self->{tls}) == Net::SSLeay::ST_OK () 1923 and Net::SSLeay::state ($self->{tls}) == Net::SSLeay::ST_OK ()
1518 and (delete $self->{_on_starttls})->($self, 1, "TLS/SSL connection established"); 1924 and (delete $self->{_on_starttls})->($self, 1, "TLS/SSL connection established");
1521=item $handle->starttls ($tls[, $tls_ctx]) 1927=item $handle->starttls ($tls[, $tls_ctx])
1522 1928
1523Instead of starting TLS negotiation immediately when the AnyEvent::Handle 1929Instead of starting TLS negotiation immediately when the AnyEvent::Handle
1524object is created, you can also do that at a later time by calling 1930object is created, you can also do that at a later time by calling
1525C<starttls>. 1931C<starttls>.
1932
1933Starting TLS is currently an asynchronous operation - when you push some
1934write data and then call C<< ->starttls >> then TLS negotiation will start
1935immediately, after which the queued write data is then sent.
1526 1936
1527The first argument is the same as the C<tls> constructor argument (either 1937The first argument is the same as the C<tls> constructor argument (either
1528C<"connect">, C<"accept"> or an existing Net::SSLeay object). 1938C<"connect">, C<"accept"> or an existing Net::SSLeay object).
1529 1939
1530The second argument is the optional C<AnyEvent::TLS> object that is used 1940The second argument is the optional C<AnyEvent::TLS> object that is used
1535The TLS connection object will end up in C<< $handle->{tls} >>, the TLS 1945The TLS connection object will end up in C<< $handle->{tls} >>, the TLS
1536context in C<< $handle->{tls_ctx} >> after this call and can be used or 1946context in C<< $handle->{tls_ctx} >> after this call and can be used or
1537changed to your liking. Note that the handshake might have already started 1947changed to your liking. Note that the handshake might have already started
1538when this function returns. 1948when this function returns.
1539 1949
1540If it an error to start a TLS handshake more than once per 1950Due to bugs in OpenSSL, it might or might not be possible to do multiple
1541AnyEvent::Handle object (this is due to bugs in OpenSSL). 1951handshakes on the same stream. It is best to not attempt to use the
1952stream after stopping TLS.
1953
1954This method may invoke callbacks (and therefore the handle might be
1955destroyed after it returns).
1542 1956
1543=cut 1957=cut
1544 1958
1545our %TLS_CACHE; #TODO not yet documented, should we? 1959our %TLS_CACHE; #TODO not yet documented, should we?
1546 1960
1547sub starttls { 1961sub starttls {
1548 my ($self, $ssl, $ctx) = @_; 1962 my ($self, $tls, $ctx) = @_;
1963
1964 Carp::croak "It is an error to call starttls on an AnyEvent::Handle object while TLS is already active, caught"
1965 if $self->{tls};
1966
1967 $self->{tls} = $tls;
1968 $self->{tls_ctx} = $ctx if @_ > 2;
1969
1970 return unless $self->{fh};
1549 1971
1550 require Net::SSLeay; 1972 require Net::SSLeay;
1551
1552 Carp::croak "it is an error to call starttls more than once on an AnyEvent::Handle object"
1553 if $self->{tls};
1554 1973
1555 $ERROR_SYSCALL = Net::SSLeay::ERROR_SYSCALL (); 1974 $ERROR_SYSCALL = Net::SSLeay::ERROR_SYSCALL ();
1556 $ERROR_WANT_READ = Net::SSLeay::ERROR_WANT_READ (); 1975 $ERROR_WANT_READ = Net::SSLeay::ERROR_WANT_READ ();
1557 1976
1977 $tls = delete $self->{tls};
1558 $ctx ||= $self->{tls_ctx}; 1978 $ctx = $self->{tls_ctx};
1979
1980 local $Carp::CarpLevel = 1; # skip ourselves when creating a new context or session
1559 1981
1560 if ("HASH" eq ref $ctx) { 1982 if ("HASH" eq ref $ctx) {
1561 require AnyEvent::TLS; 1983 require AnyEvent::TLS;
1562
1563 local $Carp::CarpLevel = 1; # skip ourselves when creating a new context
1564 1984
1565 if ($ctx->{cache}) { 1985 if ($ctx->{cache}) {
1566 my $key = $ctx+0; 1986 my $key = $ctx+0;
1567 $ctx = $TLS_CACHE{$key} ||= new AnyEvent::TLS %$ctx; 1987 $ctx = $TLS_CACHE{$key} ||= new AnyEvent::TLS %$ctx;
1568 } else { 1988 } else {
1569 $ctx = new AnyEvent::TLS %$ctx; 1989 $ctx = new AnyEvent::TLS %$ctx;
1570 } 1990 }
1571 } 1991 }
1572 1992
1573 $self->{tls_ctx} = $ctx || TLS_CTX (); 1993 $self->{tls_ctx} = $ctx || TLS_CTX ();
1574 $self->{tls} = $ssl = $self->{tls_ctx}->_get_session ($ssl, $self, $self->{peername}); 1994 $self->{tls} = $tls = $self->{tls_ctx}->_get_session ($tls, $self, $self->{peername});
1575 1995
1576 # basically, this is deep magic (because SSL_read should have the same issues) 1996 # basically, this is deep magic (because SSL_read should have the same issues)
1577 # but the openssl maintainers basically said: "trust us, it just works". 1997 # but the openssl maintainers basically said: "trust us, it just works".
1578 # (unfortunately, we have to hardcode constants because the abysmally misdesigned 1998 # (unfortunately, we have to hardcode constants because the abysmally misdesigned
1579 # and mismaintained ssleay-module doesn't even offer them). 1999 # and mismaintained ssleay-module doesn't even offer them).
1586 # and we drive openssl fully in blocking mode here. Or maybe we don't - openssl seems to 2006 # and we drive openssl fully in blocking mode here. Or maybe we don't - openssl seems to
1587 # have identity issues in that area. 2007 # have identity issues in that area.
1588# Net::SSLeay::CTX_set_mode ($ssl, 2008# Net::SSLeay::CTX_set_mode ($ssl,
1589# (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1) 2009# (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)
1590# | (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2)); 2010# | (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2));
1591 Net::SSLeay::CTX_set_mode ($ssl, 1|2); 2011 Net::SSLeay::CTX_set_mode ($tls, 1|2);
1592 2012
1593 $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); 2013 $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1594 $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); 2014 $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1595 2015
2016 Net::SSLeay::BIO_write ($self->{_rbio}, $self->{rbuf});
2017 $self->{rbuf} = "";
2018
1596 Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio}); 2019 Net::SSLeay::set_bio ($tls, $self->{_rbio}, $self->{_wbio});
1597 2020
1598 $self->{_on_starttls} = sub { $_[0]{on_starttls}(@_) } 2021 $self->{_on_starttls} = sub { $_[0]{on_starttls}(@_) }
1599 if $self->{on_starttls}; 2022 if $self->{on_starttls};
1600 2023
1601 &_dotls; # need to trigger the initial handshake 2024 &_dotls; # need to trigger the initial handshake
1604 2027
1605=item $handle->stoptls 2028=item $handle->stoptls
1606 2029
1607Shuts down the SSL connection - this makes a proper EOF handshake by 2030Shuts down the SSL connection - this makes a proper EOF handshake by
1608sending a close notify to the other side, but since OpenSSL doesn't 2031sending a close notify to the other side, but since OpenSSL doesn't
1609support non-blocking shut downs, it is not possible to re-use the stream 2032support non-blocking shut downs, it is not guaranteed that you can re-use
1610afterwards. 2033the stream afterwards.
2034
2035This method may invoke callbacks (and therefore the handle might be
2036destroyed after it returns).
1611 2037
1612=cut 2038=cut
1613 2039
1614sub stoptls { 2040sub stoptls {
1615 my ($self) = @_; 2041 my ($self) = @_;
1616 2042
1617 if ($self->{tls}) { 2043 if ($self->{tls} && $self->{fh}) {
1618 Net::SSLeay::shutdown ($self->{tls}); 2044 Net::SSLeay::shutdown ($self->{tls});
1619 2045
1620 &_dotls; 2046 &_dotls;
1621 2047
1622# # we don't give a shit. no, we do, but we can't. no...#d# 2048# # we don't give a shit. no, we do, but we can't. no...#d#
1628sub _freetls { 2054sub _freetls {
1629 my ($self) = @_; 2055 my ($self) = @_;
1630 2056
1631 return unless $self->{tls}; 2057 return unless $self->{tls};
1632 2058
1633 $self->{tls_ctx}->_put_session (delete $self->{tls}); 2059 $self->{tls_ctx}->_put_session (delete $self->{tls})
2060 if $self->{tls} > 0;
1634 2061
1635 delete @$self{qw(_rbio _wbio _tls_wbuf _on_starttls)}; 2062 delete @$self{qw(_rbio _wbio _tls_wbuf _on_starttls)};
1636} 2063}
1637 2064
2065=item $handle->resettls
2066
2067This rarely-used method simply resets and TLS state on the handle, usually
2068causing data loss.
2069
2070One case where it may be useful is when you want to skip over the data in
2071the stream but you are not interested in interpreting it, so data loss is
2072no concern.
2073
2074=cut
2075
2076*resettls = \&_freetls;
2077
1638sub DESTROY { 2078sub DESTROY {
1639 my ($self) = @_; 2079 my ($self) = @_;
1640 2080
1641 &_freetls; 2081 &_freetls;
1642 2082
1643 my $linger = exists $self->{linger} ? $self->{linger} : 3600; 2083 my $linger = exists $self->{linger} ? $self->{linger} : 3600;
1644 2084
1645 if ($linger && length $self->{wbuf}) { 2085 if ($linger && length $self->{wbuf} && $self->{fh}) {
1646 my $fh = delete $self->{fh}; 2086 my $fh = delete $self->{fh};
1647 my $wbuf = delete $self->{wbuf}; 2087 my $wbuf = delete $self->{wbuf};
1648 2088
1649 my @linger; 2089 my @linger;
1650 2090
1651 push @linger, AnyEvent->io (fh => $fh, poll => "w", cb => sub { 2091 push @linger, AE::io $fh, 1, sub {
1652 my $len = syswrite $fh, $wbuf, length $wbuf; 2092 my $len = syswrite $fh, $wbuf, length $wbuf;
1653 2093
1654 if ($len > 0) { 2094 if ($len > 0) {
1655 substr $wbuf, 0, $len, ""; 2095 substr $wbuf, 0, $len, "";
1656 } else { 2096 } elsif (defined $len || ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK)) {
1657 @linger = (); # end 2097 @linger = (); # end
1658 } 2098 }
1659 }); 2099 };
1660 push @linger, AnyEvent->timer (after => $linger, cb => sub { 2100 push @linger, AE::timer $linger, 0, sub {
1661 @linger = (); 2101 @linger = ();
1662 }); 2102 };
1663 } 2103 }
1664} 2104}
1665 2105
1666=item $handle->destroy 2106=item $handle->destroy
1667 2107
1668Shuts down the handle object as much as possible - this call ensures that 2108Shuts down the handle object as much as possible - this call ensures that
1669no further callbacks will be invoked and as many resources as possible 2109no further callbacks will be invoked and as many resources as possible
1670will be freed. You must not call any methods on the object afterwards. 2110will be freed. Any method you will call on the handle object after
2111destroying it in this way will be silently ignored (and it will return the
2112empty list).
1671 2113
1672Normally, you can just "forget" any references to an AnyEvent::Handle 2114Normally, you can just "forget" any references to an AnyEvent::Handle
1673object and it will simply shut down. This works in fatal error and EOF 2115object and it will simply shut down. This works in fatal error and EOF
1674callbacks, as well as code outside. It does I<NOT> work in a read or write 2116callbacks, as well as code outside. It does I<NOT> work in a read or write
1675callback, so when you want to destroy the AnyEvent::Handle object from 2117callback, so when you want to destroy the AnyEvent::Handle object from
1689sub destroy { 2131sub destroy {
1690 my ($self) = @_; 2132 my ($self) = @_;
1691 2133
1692 $self->DESTROY; 2134 $self->DESTROY;
1693 %$self = (); 2135 %$self = ();
2136 bless $self, "AnyEvent::Handle::destroyed";
1694} 2137}
2138
2139sub AnyEvent::Handle::destroyed::AUTOLOAD {
2140 #nop
2141}
2142
2143=item $handle->destroyed
2144
2145Returns false as long as the handle hasn't been destroyed by a call to C<<
2146->destroy >>, true otherwise.
2147
2148Can be useful to decide whether the handle is still valid after some
2149callback possibly destroyed the handle. For example, C<< ->push_write >>,
2150C<< ->starttls >> and other methods can call user callbacks, which in turn
2151can destroy the handle, so work can be avoided by checking sometimes:
2152
2153 $hdl->starttls ("accept");
2154 return if $hdl->destroyed;
2155 $hdl->push_write (...
2156
2157Note that the call to C<push_write> will silently be ignored if the handle
2158has been destroyed, so often you can just ignore the possibility of the
2159handle being destroyed.
2160
2161=cut
2162
2163sub destroyed { 0 }
2164sub AnyEvent::Handle::destroyed::destroyed { 1 }
1695 2165
1696=item AnyEvent::Handle::TLS_CTX 2166=item AnyEvent::Handle::TLS_CTX
1697 2167
1698This function creates and returns the AnyEvent::TLS object used by default 2168This function creates and returns the AnyEvent::TLS object used by default
1699for TLS mode. 2169for TLS mode.
1727 2197
1728It is only safe to "forget" the reference inside EOF or error callbacks, 2198It is only safe to "forget" the reference inside EOF or error callbacks,
1729from within all other callbacks, you need to explicitly call the C<< 2199from within all other callbacks, you need to explicitly call the C<<
1730->destroy >> method. 2200->destroy >> method.
1731 2201
2202=item Why is my C<on_eof> callback never called?
2203
2204Probably because your C<on_error> callback is being called instead: When
2205you have outstanding requests in your read queue, then an EOF is
2206considered an error as you clearly expected some data.
2207
2208To avoid this, make sure you have an empty read queue whenever your handle
2209is supposed to be "idle" (i.e. connection closes are O.K.). You can set
2210an C<on_read> handler that simply pushes the first read requests in the
2211queue.
2212
2213See also the next question, which explains this in a bit more detail.
2214
2215=item How can I serve requests in a loop?
2216
2217Most protocols consist of some setup phase (authentication for example)
2218followed by a request handling phase, where the server waits for requests
2219and handles them, in a loop.
2220
2221There are two important variants: The first (traditional, better) variant
2222handles requests until the server gets some QUIT command, causing it to
2223close the connection first (highly desirable for a busy TCP server). A
2224client dropping the connection is an error, which means this variant can
2225detect an unexpected detection close.
2226
2227To handle this case, always make sure you have a on-empty read queue, by
2228pushing the "read request start" handler on it:
2229
2230 # we assume a request starts with a single line
2231 my @start_request; @start_request = (line => sub {
2232 my ($hdl, $line) = @_;
2233
2234 ... handle request
2235
2236 # push next request read, possibly from a nested callback
2237 $hdl->push_read (@start_request);
2238 });
2239
2240 # auth done, now go into request handling loop
2241 # now push the first @start_request
2242 $hdl->push_read (@start_request);
2243
2244By always having an outstanding C<push_read>, the handle always expects
2245some data and raises the C<EPIPE> error when the connction is dropped
2246unexpectedly.
2247
2248The second variant is a protocol where the client can drop the connection
2249at any time. For TCP, this means that the server machine may run out of
2250sockets easier, and in general, it means you cannot distinguish a protocl
2251failure/client crash from a normal connection close. Nevertheless, these
2252kinds of protocols are common (and sometimes even the best solution to the
2253problem).
2254
2255Having an outstanding read request at all times is possible if you ignore
2256C<EPIPE> errors, but this doesn't help with when the client drops the
2257connection during a request, which would still be an error.
2258
2259A better solution is to push the initial request read in an C<on_read>
2260callback. This avoids an error, as when the server doesn't expect data
2261(i.e. is idly waiting for the next request, an EOF will not raise an
2262error, but simply result in an C<on_eof> callback. It is also a bit slower
2263and simpler:
2264
2265 # auth done, now go into request handling loop
2266 $hdl->on_read (sub {
2267 my ($hdl) = @_;
2268
2269 # called each time we receive data but the read queue is empty
2270 # simply start read the request
2271
2272 $hdl->push_read (line => sub {
2273 my ($hdl, $line) = @_;
2274
2275 ... handle request
2276
2277 # do nothing special when the request has been handled, just
2278 # let the request queue go empty.
2279 });
2280 });
2281
1732=item I get different callback invocations in TLS mode/Why can't I pause 2282=item I get different callback invocations in TLS mode/Why can't I pause
1733reading? 2283reading?
1734 2284
1735Unlike, say, TCP, TLS connections do not consist of two independent 2285Unlike, say, TCP, TLS connections do not consist of two independent
1736communication channels, one for each direction. Or put differently. The 2286communication channels, one for each direction. Or put differently, the
1737read and write directions are not independent of each other: you cannot 2287read and write directions are not independent of each other: you cannot
1738write data unless you are also prepared to read, and vice versa. 2288write data unless you are also prepared to read, and vice versa.
1739 2289
1740This can mean than, in TLS mode, you might get C<on_error> or C<on_eof> 2290This means that, in TLS mode, you might get C<on_error> or C<on_eof>
1741callback invocations when you are not expecting any read data - the reason 2291callback invocations when you are not expecting any read data - the reason
1742is that AnyEvent::Handle always reads in TLS mode. 2292is that AnyEvent::Handle always reads in TLS mode.
1743 2293
1744During the connection, you have to make sure that you always have a 2294During the connection, you have to make sure that you always have a
1745non-empty read-queue, or an C<on_read> watcher. At the end of the 2295non-empty read-queue, or an C<on_read> watcher. At the end of the
1757 $handle->on_eof (undef); 2307 $handle->on_eof (undef);
1758 $handle->on_error (sub { 2308 $handle->on_error (sub {
1759 my $data = delete $_[0]{rbuf}; 2309 my $data = delete $_[0]{rbuf};
1760 }); 2310 });
1761 2311
2312Note that this example removes the C<rbuf> member from the handle object,
2313which is not normally allowed by the API. It is expressly permitted in
2314this case only, as the handle object needs to be destroyed afterwards.
2315
1762The reason to use C<on_error> is that TCP connections, due to latencies 2316The reason to use C<on_error> is that TCP connections, due to latencies
1763and packets loss, might get closed quite violently with an error, when in 2317and packets loss, might get closed quite violently with an error, when in
1764fact, all data has been received. 2318fact all data has been received.
1765 2319
1766It is usually better to use acknowledgements when transferring data, 2320It is usually better to use acknowledgements when transferring data,
1767to make sure the other side hasn't just died and you got the data 2321to make sure the other side hasn't just died and you got the data
1768intact. This is also one reason why so many internet protocols have an 2322intact. This is also one reason why so many internet protocols have an
1769explicit QUIT command. 2323explicit QUIT command.
1776C<low_water_mark> this will be called precisely when all data has been 2330C<low_water_mark> this will be called precisely when all data has been
1777written to the socket: 2331written to the socket:
1778 2332
1779 $handle->push_write (...); 2333 $handle->push_write (...);
1780 $handle->on_drain (sub { 2334 $handle->on_drain (sub {
1781 warn "all data submitted to the kernel\n"; 2335 AE::log debug => "all data submitted to the kernel\n";
1782 undef $handle; 2336 undef $handle;
1783 }); 2337 });
1784 2338
1785If you just want to queue some data and then signal EOF to the other side, 2339If you just want to queue some data and then signal EOF to the other side,
1786consider using C<< ->push_shutdown >> instead. 2340consider using C<< ->push_shutdown >> instead.
1787 2341
1788=item I want to contact a TLS/SSL server, I don't care about security. 2342=item I want to contact a TLS/SSL server, I don't care about security.
1789 2343
1790If your TLS server is a pure TLS server (e.g. HTTPS) that only speaks TLS, 2344If your TLS server is a pure TLS server (e.g. HTTPS) that only speaks TLS,
1791simply connect to it and then create the AnyEvent::Handle with the C<tls> 2345connect to it and then create the AnyEvent::Handle with the C<tls>
1792parameter: 2346parameter:
1793 2347
1794 tcp_connect $host, $port, sub { 2348 tcp_connect $host, $port, sub {
1795 my ($fh) = @_; 2349 my ($fh) = @_;
1796 2350
1896 2450
1897=item * all members not documented here and not prefixed with an underscore 2451=item * all members not documented here and not prefixed with an underscore
1898are free to use in subclasses. 2452are free to use in subclasses.
1899 2453
1900Of course, new versions of AnyEvent::Handle may introduce more "public" 2454Of course, new versions of AnyEvent::Handle may introduce more "public"
1901member variables, but thats just life, at least it is documented. 2455member variables, but that's just life. At least it is documented.
1902 2456
1903=back 2457=back
1904 2458
1905=head1 AUTHOR 2459=head1 AUTHOR
1906 2460

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