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Revision 1.30 by root, Sat May 24 23:56:26 2008 UTC vs.
Revision 1.113 by root, Wed Jan 21 06:02:21 2009 UTC

1package AnyEvent::Handle; 1package AnyEvent::Handle;
2 2
3no warnings; 3no warnings;
4use strict; 4use strict qw(subs vars);
5 5
6use AnyEvent (); 6use AnyEvent ();
7use AnyEvent::Util (); 7use AnyEvent::Util qw(WSAEWOULDBLOCK);
8use Scalar::Util (); 8use Scalar::Util ();
9use Carp (); 9use Carp ();
10use Fcntl (); 10use Fcntl ();
11use Errno qw/EAGAIN EINTR/; 11use Errno qw(EAGAIN EINTR);
12 12
13=head1 NAME 13=head1 NAME
14 14
15AnyEvent::Handle - non-blocking I/O on file handles via AnyEvent 15AnyEvent::Handle - non-blocking I/O on file handles via AnyEvent
16 16
17This module is experimental.
18
19=cut 17=cut
20 18
21our $VERSION = '0.04'; 19our $VERSION = 4.331;
22 20
23=head1 SYNOPSIS 21=head1 SYNOPSIS
24 22
25 use AnyEvent; 23 use AnyEvent;
26 use AnyEvent::Handle; 24 use AnyEvent::Handle;
27 25
28 my $cv = AnyEvent->condvar; 26 my $cv = AnyEvent->condvar;
29 27
30 my $ae_fh = AnyEvent::Handle->new (fh => \*STDIN); 28 my $handle =
31
32 #TODO
33
34 # or use the constructor to pass the callback:
35
36 my $ae_fh2 =
37 AnyEvent::Handle->new ( 29 AnyEvent::Handle->new (
38 fh => \*STDIN, 30 fh => \*STDIN,
39 on_eof => sub { 31 on_eof => sub {
40 $cv->broadcast; 32 $cv->send;
41 }, 33 },
42 #TODO
43 ); 34 );
44 35
45 $cv->wait; 36 # send some request line
37 $handle->push_write ("getinfo\015\012");
38
39 # read the response line
40 $handle->push_read (line => sub {
41 my ($handle, $line) = @_;
42 warn "read line <$line>\n";
43 $cv->send;
44 });
45
46 $cv->recv;
46 47
47=head1 DESCRIPTION 48=head1 DESCRIPTION
48 49
49This module is a helper module to make it easier to do event-based I/O on 50This module is a helper module to make it easier to do event-based I/O on
50filehandles. For utility functions for doing non-blocking connects and accepts 51filehandles. For utility functions for doing non-blocking connects and accepts
51on sockets see L<AnyEvent::Util>. 52on sockets see L<AnyEvent::Util>.
52 53
54The L<AnyEvent::Intro> tutorial contains some well-documented
55AnyEvent::Handle examples.
56
53In the following, when the documentation refers to of "bytes" then this 57In the following, when the documentation refers to of "bytes" then this
54means characters. As sysread and syswrite are used for all I/O, their 58means characters. As sysread and syswrite are used for all I/O, their
55treatment of characters applies to this module as well. 59treatment of characters applies to this module as well.
56 60
57All callbacks will be invoked with the handle object as their first 61All callbacks will be invoked with the handle object as their first
69 73
70=item fh => $filehandle [MANDATORY] 74=item fh => $filehandle [MANDATORY]
71 75
72The filehandle this L<AnyEvent::Handle> object will operate on. 76The filehandle this L<AnyEvent::Handle> object will operate on.
73 77
74NOTE: The filehandle will be set to non-blocking (using 78NOTE: The filehandle will be set to non-blocking mode (using
75AnyEvent::Util::fh_nonblocking). 79C<AnyEvent::Util::fh_nonblocking>) by the constructor and needs to stay in
80that mode.
76 81
77=item on_eof => $cb->($self) 82=item on_eof => $cb->($handle)
78 83
79Set the callback to be called on EOF. 84Set 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
86connection cleanly.
80 87
88For 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
90callback and continue writing data, as only the read part has been shut
91down.
92
81While not mandatory, it is highly recommended to set an eof callback, 93While not mandatory, it is I<highly> recommended to set an EOF callback,
82otherwise you might end up with a closed socket while you are still 94otherwise you might end up with a closed socket while you are still
83waiting for data. 95waiting for data.
84 96
97If 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>.
99
85=item on_error => $cb->($self) 100=item on_error => $cb->($handle, $fatal)
86 101
87This is the fatal error callback, that is called when, well, a fatal error 102This is the error callback, which is called when, well, some error
88occurs, such as not being able to resolve the hostname, failure to connect 103occured, such as not being able to resolve the hostname, failure to
89or a read error. 104connect or a read error.
90 105
91The object will not be in a usable state when this callback has been 106Some errors are fatal (which is indicated by C<$fatal> being true). On
92called. 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>).
93 116
94On callback entrance, the value of C<$!> contains the operating system 117On callback entrance, the value of C<$!> contains the operating system
95error (or C<ENOSPC>, C<EPIPE> or C<EBADMSG>). 118error (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT> or C<EBADMSG>).
96 119
97While not mandatory, it is I<highly> recommended to set this callback, as 120While not mandatory, it is I<highly> recommended to set this callback, as
98you will not be notified of errors otherwise. The default simply calls 121you will not be notified of errors otherwise. The default simply calls
99die. 122C<croak>.
100 123
101=item on_read => $cb->($self) 124=item on_read => $cb->($handle)
102 125
103This sets the default read callback, which is called when data arrives 126This sets the default read callback, which is called when data arrives
104and no read request is in the queue. 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).
105 130
106To access (and remove data from) the read buffer, use the C<< ->rbuf >> 131To access (and remove data from) the read buffer, use the C<< ->rbuf >>
107method or access the C<$self->{rbuf}> member directly. 132method or access the C<$handle->{rbuf}> member directly.
108 133
109When an EOF condition is detected then AnyEvent::Handle will first try to 134When an EOF condition is detected then AnyEvent::Handle will first try to
110feed all the remaining data to the queued callbacks and C<on_read> before 135feed all the remaining data to the queued callbacks and C<on_read> before
111calling the C<on_eof> callback. If no progress can be made, then a fatal 136calling the C<on_eof> callback. If no progress can be made, then a fatal
112error will be raised (with C<$!> set to C<EPIPE>). 137error will be raised (with C<$!> set to C<EPIPE>).
113 138
114=item on_drain => $cb->() 139=item on_drain => $cb->($handle)
115 140
116This sets the callback that is called when the write buffer becomes empty 141This sets the callback that is called when the write buffer becomes empty
117(or when the callback is set and the buffer is empty already). 142(or when the callback is set and the buffer is empty already).
118 143
119To append to the write buffer, use the C<< ->push_write >> method. 144To append to the write buffer, use the C<< ->push_write >> method.
120 145
146This callback is useful when you don't want to put all of your write data
147into the queue at once, for example, when you want to write the contents
148of some file to the socket you might not want to read the whole file into
149memory and push it into the queue, but instead only read more data from
150the file when the write queue becomes empty.
151
152=item timeout => $fractional_seconds
153
154If non-zero, then this enables an "inactivity" timeout: whenever this many
155seconds pass without a successful read or write on the underlying file
156handle, the C<on_timeout> callback will be invoked (and if that one is
157missing, a non-fatal C<ETIMEDOUT> error will be raised).
158
159Note that timeout processing is also active when you currently do not have
160any outstanding read or write requests: If you plan to keep the connection
161idle then you should disable the timout temporarily or ignore the timeout
162in the C<on_timeout> callback, in which case AnyEvent::Handle will simply
163restart the timeout.
164
165Zero (the default) disables this timeout.
166
167=item on_timeout => $cb->($handle)
168
169Called whenever the inactivity timeout passes. If you return from this
170callback, then the timeout will be reset as if some activity had happened,
171so this condition is not fatal in any way.
172
121=item rbuf_max => <bytes> 173=item rbuf_max => <bytes>
122 174
123If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>) 175If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)
124when the read buffer ever (strictly) exceeds this size. This is useful to 176when the read buffer ever (strictly) exceeds this size. This is useful to
125avoid denial-of-service attacks. 177avoid some forms of denial-of-service attacks.
126 178
127For example, a server accepting connections from untrusted sources should 179For example, a server accepting connections from untrusted sources should
128be configured to accept only so-and-so much data that it cannot act on 180be configured to accept only so-and-so much data that it cannot act on
129(for example, when expecting a line, an attacker could send an unlimited 181(for example, when expecting a line, an attacker could send an unlimited
130amount of data without a callback ever being called as long as the line 182amount of data without a callback ever being called as long as the line
131isn't finished). 183isn't finished).
132 184
185=item autocork => <boolean>
186
187When disabled (the default), then C<push_write> will try to immediately
188write the data to the handle, if possible. This avoids having to register
189a write watcher and wait for the next event loop iteration, but can
190be inefficient if you write multiple small chunks (on the wire, this
191disadvantage is usually avoided by your kernel's nagle algorithm, see
192C<no_delay>, but this option can save costly syscalls).
193
194When enabled, then writes will always be queued till the next event loop
195iteration. This is efficient when you do many small writes per iteration,
196but less efficient when you do a single write only per iteration (or when
197the write buffer often is full). It also increases write latency.
198
199=item no_delay => <boolean>
200
201When doing small writes on sockets, your operating system kernel might
202wait a bit for more data before actually sending it out. This is called
203the Nagle algorithm, and usually it is beneficial.
204
205In some situations you want as low a delay as possible, which can be
206accomplishd by setting this option to a true value.
207
208The default is your opertaing system's default behaviour (most likely
209enabled), this option explicitly enables or disables it, if possible.
210
133=item read_size => <bytes> 211=item read_size => <bytes>
134 212
135The default read block size (the amount of bytes this module will try to read 213The default read block size (the amount of bytes this module will
136on each [loop iteration). Default: C<4096>. 214try to read during each loop iteration, which affects memory
215requirements). Default: C<8192>.
137 216
138=item low_water_mark => <bytes> 217=item low_water_mark => <bytes>
139 218
140Sets the amount of bytes (default: C<0>) that make up an "empty" write 219Sets the amount of bytes (default: C<0>) that make up an "empty" write
141buffer: If the write reaches this size or gets even samller it is 220buffer: If the write reaches this size or gets even samller it is
142considered empty. 221considered empty.
143 222
223Sometimes it can be beneficial (for performance reasons) to add data to
224the write buffer before it is fully drained, but this is a rare case, as
225the operating system kernel usually buffers data as well, so the default
226is good in almost all cases.
227
228=item linger => <seconds>
229
230If non-zero (default: C<3600>), then the destructor of the
231AnyEvent::Handle object will check whether there is still outstanding
232write data and will install a watcher that will write this data to the
233socket. No errors will be reported (this mostly matches how the operating
234system treats outstanding data at socket close time).
235
236This will not work for partial TLS data that could not be encoded
237yet. This data will be lost. Calling the C<stoptls> method in time might
238help.
239
144=item tls => "accept" | "connect" | Net::SSLeay::SSL object 240=item tls => "accept" | "connect" | Net::SSLeay::SSL object
145 241
146When this parameter is given, it enables TLS (SSL) mode, that means it 242When this parameter is given, it enables TLS (SSL) mode, that means
147will start making tls handshake and will transparently encrypt/decrypt 243AnyEvent will start a TLS handshake as soon as the conenction has been
148data. 244established and will transparently encrypt/decrypt data afterwards.
149 245
150TLS mode requires Net::SSLeay to be installed (it will be loaded 246TLS mode requires Net::SSLeay to be installed (it will be loaded
151automatically when you try to create a TLS handle). 247automatically when you try to create a TLS handle): this module doesn't
248have a dependency on that module, so if your module requires it, you have
249to add the dependency yourself.
152 250
153For the TLS server side, use C<accept>, and for the TLS client side of a 251Unlike TCP, TLS has a server and client side: for the TLS server side, use
154connection, use C<connect> mode. 252C<accept>, and for the TLS client side of a connection, use C<connect>
253mode.
155 254
156You can also provide your own TLS connection object, but you have 255You can also provide your own TLS connection object, but you have
157to make sure that you call either C<Net::SSLeay::set_connect_state> 256to make sure that you call either C<Net::SSLeay::set_connect_state>
158or C<Net::SSLeay::set_accept_state> on it before you pass it to 257or C<Net::SSLeay::set_accept_state> on it before you pass it to
159AnyEvent::Handle. 258AnyEvent::Handle.
160 259
260B<IMPORTANT:> since Net::SSLeay "objects" are really only integers,
261passing in the wrong integer will lead to certain crash. This most often
262happens when one uses a stylish C<< tls => 1 >> and is surprised about the
263segmentation fault.
264
161See the C<starttls> method if you need to start TLs negotiation later. 265See the C<< ->starttls >> method for when need to start TLS negotiation later.
162 266
163=item tls_ctx => $ssl_ctx 267=item tls_ctx => $ssl_ctx
164 268
165Use the given Net::SSLeay::CTX object to create the new TLS connection 269Use the given C<Net::SSLeay::CTX> object to create the new TLS connection
166(unless a connection object was specified directly). If this parameter is 270(unless a connection object was specified directly). If this parameter is
167missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>. 271missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>.
168 272
273=item json => JSON or JSON::XS object
274
275This is the json coder object used by the C<json> read and write types.
276
277If you don't supply it, then AnyEvent::Handle will create and use a
278suitable one (on demand), which will write and expect UTF-8 encoded JSON
279texts.
280
281Note that you are responsible to depend on the JSON module if you want to
282use this functionality, as AnyEvent does not have a dependency itself.
283
169=back 284=back
170 285
171=cut 286=cut
172 287
173sub new { 288sub new {
177 292
178 $self->{fh} or Carp::croak "mandatory argument fh is missing"; 293 $self->{fh} or Carp::croak "mandatory argument fh is missing";
179 294
180 AnyEvent::Util::fh_nonblocking $self->{fh}, 1; 295 AnyEvent::Util::fh_nonblocking $self->{fh}, 1;
181 296
182 if ($self->{tls}) {
183 require Net::SSLeay;
184 $self->starttls (delete $self->{tls}, delete $self->{tls_ctx}); 297 $self->starttls (delete $self->{tls}, delete $self->{tls_ctx})
185 } 298 if $self->{tls};
186 299
187 $self->on_eof (delete $self->{on_eof} ) if $self->{on_eof}; 300 $self->{_activity} = AnyEvent->now;
188 $self->on_error (delete $self->{on_error}) if $self->{on_error}; 301 $self->_timeout;
302
189 $self->on_drain (delete $self->{on_drain}) if $self->{on_drain}; 303 $self->on_drain (delete $self->{on_drain}) if exists $self->{on_drain};
190 $self->on_read (delete $self->{on_read} ) if $self->{on_read}; 304 $self->no_delay (delete $self->{no_delay}) if exists $self->{no_delay};
191 305
192 $self->start_read; 306 $self->start_read
307 if $self->{on_read};
193 308
194 $self 309 $self
195} 310}
196 311
197sub _shutdown { 312sub _shutdown {
198 my ($self) = @_; 313 my ($self) = @_;
199 314
315 delete $self->{_tw};
200 delete $self->{rw}; 316 delete $self->{_rw};
201 delete $self->{ww}; 317 delete $self->{_ww};
202 delete $self->{fh}; 318 delete $self->{fh};
203}
204 319
320 &_freetls;
321
322 delete $self->{on_read};
323 delete $self->{_queue};
324}
325
205sub error { 326sub _error {
206 my ($self) = @_; 327 my ($self, $errno, $fatal) = @_;
207 328
208 {
209 local $!;
210 $self->_shutdown; 329 $self->_shutdown
211 } 330 if $fatal;
331
332 $! = $errno;
212 333
213 if ($self->{on_error}) { 334 if ($self->{on_error}) {
214 $self->{on_error}($self); 335 $self->{on_error}($self, $fatal);
215 } else { 336 } elsif ($self->{fh}) {
216 Carp::croak "AnyEvent::Handle uncaught fatal error: $!"; 337 Carp::croak "AnyEvent::Handle uncaught error: $!";
217 } 338 }
218} 339}
219 340
220=item $fh = $handle->fh 341=item $fh = $handle->fh
221 342
222This method returns the file handle of the L<AnyEvent::Handle> object. 343This method returns the file handle used to create the L<AnyEvent::Handle> object.
223 344
224=cut 345=cut
225 346
226sub fh { $_[0]->{fh} } 347sub fh { $_[0]{fh} }
227 348
228=item $handle->on_error ($cb) 349=item $handle->on_error ($cb)
229 350
230Replace the current C<on_error> callback (see the C<on_error> constructor argument). 351Replace the current C<on_error> callback (see the C<on_error> constructor argument).
231 352
243 364
244sub on_eof { 365sub on_eof {
245 $_[0]{on_eof} = $_[1]; 366 $_[0]{on_eof} = $_[1];
246} 367}
247 368
369=item $handle->on_timeout ($cb)
370
371Replace the current C<on_timeout> callback, or disables the callback (but
372not the timeout) if C<$cb> = C<undef>. See the C<timeout> constructor
373argument and method.
374
375=cut
376
377sub on_timeout {
378 $_[0]{on_timeout} = $_[1];
379}
380
381=item $handle->autocork ($boolean)
382
383Enables or disables the current autocork behaviour (see C<autocork>
384constructor argument). Changes will only take effect on the next write.
385
386=cut
387
388sub autocork {
389 $_[0]{autocork} = $_[1];
390}
391
392=item $handle->no_delay ($boolean)
393
394Enables or disables the C<no_delay> setting (see constructor argument of
395the same name for details).
396
397=cut
398
399sub no_delay {
400 $_[0]{no_delay} = $_[1];
401
402 eval {
403 local $SIG{__DIE__};
404 setsockopt $_[0]{fh}, &Socket::IPPROTO_TCP, &Socket::TCP_NODELAY, int $_[1];
405 };
406}
407
408#############################################################################
409
410=item $handle->timeout ($seconds)
411
412Configures (or disables) the inactivity timeout.
413
414=cut
415
416sub timeout {
417 my ($self, $timeout) = @_;
418
419 $self->{timeout} = $timeout;
420 $self->_timeout;
421}
422
423# reset the timeout watcher, as neccessary
424# also check for time-outs
425sub _timeout {
426 my ($self) = @_;
427
428 if ($self->{timeout}) {
429 my $NOW = AnyEvent->now;
430
431 # when would the timeout trigger?
432 my $after = $self->{_activity} + $self->{timeout} - $NOW;
433
434 # now or in the past already?
435 if ($after <= 0) {
436 $self->{_activity} = $NOW;
437
438 if ($self->{on_timeout}) {
439 $self->{on_timeout}($self);
440 } else {
441 $self->_error (&Errno::ETIMEDOUT);
442 }
443
444 # callback could have changed timeout value, optimise
445 return unless $self->{timeout};
446
447 # calculate new after
448 $after = $self->{timeout};
449 }
450
451 Scalar::Util::weaken $self;
452 return unless $self; # ->error could have destroyed $self
453
454 $self->{_tw} ||= AnyEvent->timer (after => $after, cb => sub {
455 delete $self->{_tw};
456 $self->_timeout;
457 });
458 } else {
459 delete $self->{_tw};
460 }
461}
462
248############################################################################# 463#############################################################################
249 464
250=back 465=back
251 466
252=head2 WRITE QUEUE 467=head2 WRITE QUEUE
273 my ($self, $cb) = @_; 488 my ($self, $cb) = @_;
274 489
275 $self->{on_drain} = $cb; 490 $self->{on_drain} = $cb;
276 491
277 $cb->($self) 492 $cb->($self)
278 if $cb && $self->{low_water_mark} >= length $self->{wbuf}; 493 if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf});
279} 494}
280 495
281=item $handle->push_write ($data) 496=item $handle->push_write ($data)
282 497
283Queues the given scalar to be written. You can push as much data as you 498Queues the given scalar to be written. You can push as much data as you
287=cut 502=cut
288 503
289sub _drain_wbuf { 504sub _drain_wbuf {
290 my ($self) = @_; 505 my ($self) = @_;
291 506
292 if (!$self->{ww} && length $self->{wbuf}) { 507 if (!$self->{_ww} && length $self->{wbuf}) {
508
293 Scalar::Util::weaken $self; 509 Scalar::Util::weaken $self;
510
294 my $cb = sub { 511 my $cb = sub {
295 my $len = syswrite $self->{fh}, $self->{wbuf}; 512 my $len = syswrite $self->{fh}, $self->{wbuf};
296 513
297 if ($len >= 0) { 514 if ($len >= 0) {
298 substr $self->{wbuf}, 0, $len, ""; 515 substr $self->{wbuf}, 0, $len, "";
299 516
517 $self->{_activity} = AnyEvent->now;
518
300 $self->{on_drain}($self) 519 $self->{on_drain}($self)
301 if $self->{low_water_mark} >= length $self->{wbuf} 520 if $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf})
302 && $self->{on_drain}; 521 && $self->{on_drain};
303 522
304 delete $self->{ww} unless length $self->{wbuf}; 523 delete $self->{_ww} unless length $self->{wbuf};
305 } elsif ($! != EAGAIN && $! != EINTR) { 524 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
306 $self->error; 525 $self->_error ($!, 1);
307 } 526 }
308 }; 527 };
309 528
529 # try to write data immediately
530 $cb->() unless $self->{autocork};
531
532 # if still data left in wbuf, we need to poll
310 $self->{ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb); 533 $self->{_ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb)
311 534 if length $self->{wbuf};
312 $cb->($self);
313 }; 535 };
314} 536}
315 537
316our %WH; 538our %WH;
317 539
327 549
328 @_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write") 550 @_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write")
329 ->($self, @_); 551 ->($self, @_);
330 } 552 }
331 553
332 if ($self->{filter_w}) { 554 if ($self->{tls}) {
333 $self->{filter_w}->($self, \$_[0]); 555 $self->{_tls_wbuf} .= $_[0];
556
557 &_dotls ($self);
334 } else { 558 } else {
335 $self->{wbuf} .= $_[0]; 559 $self->{wbuf} .= $_[0];
336 $self->_drain_wbuf; 560 $self->_drain_wbuf;
337 } 561 }
338} 562}
339 563
340=item $handle->push_write (type => @args) 564=item $handle->push_write (type => @args)
341 565
342=item $handle->unshift_write (type => @args)
343
344Instead of formatting your data yourself, you can also let this module do 566Instead of formatting your data yourself, you can also let this module do
345the job by specifying a type and type-specific arguments. 567the job by specifying a type and type-specific arguments.
346 568
347Predefined types are (if you have ideas for additional types, feel free to 569Predefined types are (if you have ideas for additional types, feel free to
348drop by and tell us): 570drop by and tell us):
352=item netstring => $string 574=item netstring => $string
353 575
354Formats the given value as netstring 576Formats the given value as netstring
355(http://cr.yp.to/proto/netstrings.txt, this is not a recommendation to use them). 577(http://cr.yp.to/proto/netstrings.txt, this is not a recommendation to use them).
356 578
357=back
358
359=cut 579=cut
360 580
361register_write_type netstring => sub { 581register_write_type netstring => sub {
362 my ($self, $string) = @_; 582 my ($self, $string) = @_;
363 583
364 sprintf "%d:%s,", (length $string), $string 584 (length $string) . ":$string,"
365}; 585};
366 586
587=item packstring => $format, $data
588
589An octet string prefixed with an encoded length. The encoding C<$format>
590uses the same format as a Perl C<pack> format, but must specify a single
591integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
592optional C<!>, C<< < >> or C<< > >> modifier).
593
594=cut
595
596register_write_type packstring => sub {
597 my ($self, $format, $string) = @_;
598
599 pack "$format/a*", $string
600};
601
602=item json => $array_or_hashref
603
604Encodes the given hash or array reference into a JSON object. Unless you
605provide your own JSON object, this means it will be encoded to JSON text
606in UTF-8.
607
608JSON objects (and arrays) are self-delimiting, so you can write JSON at
609one end of a handle and read them at the other end without using any
610additional framing.
611
612The generated JSON text is guaranteed not to contain any newlines: While
613this module doesn't need delimiters after or between JSON texts to be
614able to read them, many other languages depend on that.
615
616A simple RPC protocol that interoperates easily with others is to send
617JSON arrays (or objects, although arrays are usually the better choice as
618they mimic how function argument passing works) and a newline after each
619JSON text:
620
621 $handle->push_write (json => ["method", "arg1", "arg2"]); # whatever
622 $handle->push_write ("\012");
623
624An AnyEvent::Handle receiver would simply use the C<json> read type and
625rely on the fact that the newline will be skipped as leading whitespace:
626
627 $handle->push_read (json => sub { my $array = $_[1]; ... });
628
629Other languages could read single lines terminated by a newline and pass
630this line into their JSON decoder of choice.
631
632=cut
633
634register_write_type json => sub {
635 my ($self, $ref) = @_;
636
637 require JSON;
638
639 $self->{json} ? $self->{json}->encode ($ref)
640 : JSON::encode_json ($ref)
641};
642
643=item storable => $reference
644
645Freezes the given reference using L<Storable> and writes it to the
646handle. Uses the C<nfreeze> format.
647
648=cut
649
650register_write_type storable => sub {
651 my ($self, $ref) = @_;
652
653 require Storable;
654
655 pack "w/a*", Storable::nfreeze ($ref)
656};
657
658=back
659
367=item AnyEvent::Handle::register_write_type type => $coderef->($self, @args) 660=item AnyEvent::Handle::register_write_type type => $coderef->($handle, @args)
368 661
369This function (not method) lets you add your own types to C<push_write>. 662This function (not method) lets you add your own types to C<push_write>.
370Whenever the given C<type> is used, C<push_write> will invoke the code 663Whenever the given C<type> is used, C<push_write> will invoke the code
371reference with the handle object and the remaining arguments. 664reference with the handle object and the remaining arguments.
372 665
391ways, the "simple" way, using only C<on_read> and the "complex" way, using 684ways, the "simple" way, using only C<on_read> and the "complex" way, using
392a queue. 685a queue.
393 686
394In the simple case, you just install an C<on_read> callback and whenever 687In the simple case, you just install an C<on_read> callback and whenever
395new data arrives, it will be called. You can then remove some data (if 688new data arrives, it will be called. You can then remove some data (if
396enough is there) from the read buffer (C<< $handle->rbuf >>) if you want 689enough is there) from the read buffer (C<< $handle->rbuf >>). Or you cna
397or not. 690leave the data there if you want to accumulate more (e.g. when only a
691partial message has been received so far).
398 692
399In the more complex case, you want to queue multiple callbacks. In this 693In the more complex case, you want to queue multiple callbacks. In this
400case, AnyEvent::Handle will call the first queued callback each time new 694case, AnyEvent::Handle will call the first queued callback each time new
401data arrives and removes it when it has done its job (see C<push_read>, 695data arrives (also the first time it is queued) and removes it when it has
402below). 696done its job (see C<push_read>, below).
403 697
404This way you can, for example, push three line-reads, followed by reading 698This way you can, for example, push three line-reads, followed by reading
405a chunk of data, and AnyEvent::Handle will execute them in order. 699a chunk of data, and AnyEvent::Handle will execute them in order.
406 700
407Example 1: EPP protocol parser. EPP sends 4 byte length info, followed by 701Example 1: EPP protocol parser. EPP sends 4 byte length info, followed by
408the specified number of bytes which give an XML datagram. 702the specified number of bytes which give an XML datagram.
409 703
410 # in the default state, expect some header bytes 704 # in the default state, expect some header bytes
411 $handle->on_read (sub { 705 $handle->on_read (sub {
412 # some data is here, now queue the length-header-read (4 octets) 706 # some data is here, now queue the length-header-read (4 octets)
413 shift->unshift_read_chunk (4, sub { 707 shift->unshift_read (chunk => 4, sub {
414 # header arrived, decode 708 # header arrived, decode
415 my $len = unpack "N", $_[1]; 709 my $len = unpack "N", $_[1];
416 710
417 # now read the payload 711 # now read the payload
418 shift->unshift_read_chunk ($len, sub { 712 shift->unshift_read (chunk => $len, sub {
419 my $xml = $_[1]; 713 my $xml = $_[1];
420 # handle xml 714 # handle xml
421 }); 715 });
422 }); 716 });
423 }); 717 });
424 718
425Example 2: Implement a client for a protocol that replies either with 719Example 2: Implement a client for a protocol that replies either with "OK"
426"OK" and another line or "ERROR" for one request, and 64 bytes for the 720and another line or "ERROR" for the first request that is sent, and 64
427second request. Due tot he availability of a full queue, we can just 721bytes for the second request. Due to the availability of a queue, we can
428pipeline sending both requests and manipulate the queue as necessary in 722just pipeline sending both requests and manipulate the queue as necessary
429the callbacks: 723in the callbacks.
430 724
431 # request one 725When the first callback is called and sees an "OK" response, it will
726C<unshift> another line-read. This line-read will be queued I<before> the
72764-byte chunk callback.
728
729 # request one, returns either "OK + extra line" or "ERROR"
432 $handle->push_write ("request 1\015\012"); 730 $handle->push_write ("request 1\015\012");
433 731
434 # we expect "ERROR" or "OK" as response, so push a line read 732 # we expect "ERROR" or "OK" as response, so push a line read
435 $handle->push_read_line (sub { 733 $handle->push_read (line => sub {
436 # if we got an "OK", we have to _prepend_ another line, 734 # if we got an "OK", we have to _prepend_ another line,
437 # so it will be read before the second request reads its 64 bytes 735 # so it will be read before the second request reads its 64 bytes
438 # which are already in the queue when this callback is called 736 # which are already in the queue when this callback is called
439 # we don't do this in case we got an error 737 # we don't do this in case we got an error
440 if ($_[1] eq "OK") { 738 if ($_[1] eq "OK") {
441 $_[0]->unshift_read_line (sub { 739 $_[0]->unshift_read (line => sub {
442 my $response = $_[1]; 740 my $response = $_[1];
443 ... 741 ...
444 }); 742 });
445 } 743 }
446 }); 744 });
447 745
448 # request two 746 # request two, simply returns 64 octets
449 $handle->push_write ("request 2\015\012"); 747 $handle->push_write ("request 2\015\012");
450 748
451 # simply read 64 bytes, always 749 # simply read 64 bytes, always
452 $handle->push_read_chunk (64, sub { 750 $handle->push_read (chunk => 64, sub {
453 my $response = $_[1]; 751 my $response = $_[1];
454 ... 752 ...
455 }); 753 });
456 754
457=over 4 755=over 4
458 756
459=cut 757=cut
460 758
461sub _drain_rbuf { 759sub _drain_rbuf {
462 my ($self) = @_; 760 my ($self) = @_;
761
762 local $self->{_in_drain} = 1;
463 763
464 if ( 764 if (
465 defined $self->{rbuf_max} 765 defined $self->{rbuf_max}
466 && $self->{rbuf_max} < length $self->{rbuf} 766 && $self->{rbuf_max} < length $self->{rbuf}
467 ) { 767 ) {
468 $! = &Errno::ENOSPC; return $self->error; 768 $self->_error (&Errno::ENOSPC, 1), return;
469 } 769 }
470 770
471 return if $self->{in_drain}; 771 while () {
472 local $self->{in_drain} = 1;
473
474 while (my $len = length $self->{rbuf}) { 772 my $len = length $self->{rbuf};
475 no strict 'refs'; 773
476 if (my $cb = shift @{ $self->{queue} }) { 774 if (my $cb = shift @{ $self->{_queue} }) {
477 unless ($cb->($self)) { 775 unless ($cb->($self)) {
478 if ($self->{eof}) { 776 if ($self->{_eof}) {
479 # no progress can be made (not enough data and no data forthcoming) 777 # no progress can be made (not enough data and no data forthcoming)
480 $! = &Errno::EPIPE; return $self->error; 778 $self->_error (&Errno::EPIPE, 1), return;
481 } 779 }
482 780
483 unshift @{ $self->{queue} }, $cb; 781 unshift @{ $self->{_queue} }, $cb;
484 return; 782 last;
485 } 783 }
486 } elsif ($self->{on_read}) { 784 } elsif ($self->{on_read}) {
785 last unless $len;
786
487 $self->{on_read}($self); 787 $self->{on_read}($self);
488 788
489 if ( 789 if (
490 $self->{eof} # if no further data will arrive
491 && $len == length $self->{rbuf} # and no data has been consumed 790 $len == length $self->{rbuf} # if no data has been consumed
492 && !@{ $self->{queue} } # and the queue is still empty 791 && !@{ $self->{_queue} } # and the queue is still empty
493 && $self->{on_read} # and we still want to read data 792 && $self->{on_read} # but we still have on_read
494 ) { 793 ) {
794 # no further data will arrive
495 # then no progress can be made 795 # so no progress can be made
496 $! = &Errno::EPIPE; return $self->error; 796 $self->_error (&Errno::EPIPE, 1), return
797 if $self->{_eof};
798
799 last; # more data might arrive
497 } 800 }
498 } else { 801 } else {
499 # read side becomes idle 802 # read side becomes idle
500 delete $self->{rw}; 803 delete $self->{_rw} unless $self->{tls};
501 return; 804 last;
502 } 805 }
503 } 806 }
504 807
505 if ($self->{eof}) { 808 if ($self->{_eof}) {
506 $self->_shutdown; 809 if ($self->{on_eof}) {
507 $self->{on_eof}($self) 810 $self->{on_eof}($self)
508 if $self->{on_eof}; 811 } else {
812 $self->_error (0, 1);
813 }
814 }
815
816 # may need to restart read watcher
817 unless ($self->{_rw}) {
818 $self->start_read
819 if $self->{on_read} || @{ $self->{_queue} };
509 } 820 }
510} 821}
511 822
512=item $handle->on_read ($cb) 823=item $handle->on_read ($cb)
513 824
519 830
520sub on_read { 831sub on_read {
521 my ($self, $cb) = @_; 832 my ($self, $cb) = @_;
522 833
523 $self->{on_read} = $cb; 834 $self->{on_read} = $cb;
835 $self->_drain_rbuf if $cb && !$self->{_in_drain};
524} 836}
525 837
526=item $handle->rbuf 838=item $handle->rbuf
527 839
528Returns the read buffer (as a modifiable lvalue). 840Returns the read buffer (as a modifiable lvalue).
576 888
577 $cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_read") 889 $cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_read")
578 ->($self, $cb, @_); 890 ->($self, $cb, @_);
579 } 891 }
580 892
581 push @{ $self->{queue} }, $cb; 893 push @{ $self->{_queue} }, $cb;
582 $self->_drain_rbuf; 894 $self->_drain_rbuf unless $self->{_in_drain};
583} 895}
584 896
585sub unshift_read { 897sub unshift_read {
586 my $self = shift; 898 my $self = shift;
587 my $cb = pop; 899 my $cb = pop;
592 $cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::unshift_read") 904 $cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::unshift_read")
593 ->($self, $cb, @_); 905 ->($self, $cb, @_);
594 } 906 }
595 907
596 908
597 unshift @{ $self->{queue} }, $cb; 909 unshift @{ $self->{_queue} }, $cb;
598 $self->_drain_rbuf; 910 $self->_drain_rbuf unless $self->{_in_drain};
599} 911}
600 912
601=item $handle->push_read (type => @args, $cb) 913=item $handle->push_read (type => @args, $cb)
602 914
603=item $handle->unshift_read (type => @args, $cb) 915=item $handle->unshift_read (type => @args, $cb)
609Predefined types are (if you have ideas for additional types, feel free to 921Predefined types are (if you have ideas for additional types, feel free to
610drop by and tell us): 922drop by and tell us):
611 923
612=over 4 924=over 4
613 925
614=item chunk => $octets, $cb->($self, $data) 926=item chunk => $octets, $cb->($handle, $data)
615 927
616Invoke the callback only once C<$octets> bytes have been read. Pass the 928Invoke the callback only once C<$octets> bytes have been read. Pass the
617data read to the callback. The callback will never be called with less 929data read to the callback. The callback will never be called with less
618data. 930data.
619 931
633 $cb->($_[0], substr $_[0]{rbuf}, 0, $len, ""); 945 $cb->($_[0], substr $_[0]{rbuf}, 0, $len, "");
634 1 946 1
635 } 947 }
636}; 948};
637 949
638# compatibility with older API
639sub push_read_chunk {
640 $_[0]->push_read (chunk => $_[1], $_[2]);
641}
642
643sub unshift_read_chunk {
644 $_[0]->unshift_read (chunk => $_[1], $_[2]);
645}
646
647=item line => [$eol, ]$cb->($self, $line, $eol) 950=item line => [$eol, ]$cb->($handle, $line, $eol)
648 951
649The callback will be called only once a full line (including the end of 952The callback will be called only once a full line (including the end of
650line marker, C<$eol>) has been read. This line (excluding the end of line 953line marker, C<$eol>) has been read. This line (excluding the end of line
651marker) will be passed to the callback as second argument (C<$line>), and 954marker) will be passed to the callback as second argument (C<$line>), and
652the end of line marker as the third argument (C<$eol>). 955the end of line marker as the third argument (C<$eol>).
666=cut 969=cut
667 970
668register_read_type line => sub { 971register_read_type line => sub {
669 my ($self, $cb, $eol) = @_; 972 my ($self, $cb, $eol) = @_;
670 973
671 $eol = qr|(\015?\012)| if @_ < 3; 974 if (@_ < 3) {
975 # this is more than twice as fast as the generic code below
976 sub {
977 $_[0]{rbuf} =~ s/^([^\015\012]*)(\015?\012)// or return;
978
979 $cb->($_[0], $1, $2);
980 1
981 }
982 } else {
672 $eol = quotemeta $eol unless ref $eol; 983 $eol = quotemeta $eol unless ref $eol;
673 $eol = qr|^(.*?)($eol)|s; 984 $eol = qr|^(.*?)($eol)|s;
985
986 sub {
987 $_[0]{rbuf} =~ s/$eol// or return;
988
989 $cb->($_[0], $1, $2);
990 1
991 }
992 }
993};
994
995=item regex => $accept[, $reject[, $skip], $cb->($handle, $data)
996
997Makes a regex match against the regex object C<$accept> and returns
998everything up to and including the match.
999
1000Example: read a single line terminated by '\n'.
1001
1002 $handle->push_read (regex => qr<\n>, sub { ... });
1003
1004If C<$reject> is given and not undef, then it determines when the data is
1005to be rejected: it is matched against the data when the C<$accept> regex
1006does not match and generates an C<EBADMSG> error when it matches. This is
1007useful to quickly reject wrong data (to avoid waiting for a timeout or a
1008receive buffer overflow).
1009
1010Example: expect a single decimal number followed by whitespace, reject
1011anything else (not the use of an anchor).
1012
1013 $handle->push_read (regex => qr<^[0-9]+\s>, qr<[^0-9]>, sub { ... });
1014
1015If C<$skip> is given and not C<undef>, then it will be matched against
1016the receive buffer when neither C<$accept> nor C<$reject> match,
1017and everything preceding and including the match will be accepted
1018unconditionally. This is useful to skip large amounts of data that you
1019know cannot be matched, so that the C<$accept> or C<$reject> regex do not
1020have to start matching from the beginning. This is purely an optimisation
1021and is usually worth only when you expect more than a few kilobytes.
1022
1023Example: expect a http header, which ends at C<\015\012\015\012>. Since we
1024expect the header to be very large (it isn't in practise, but...), we use
1025a skip regex to skip initial portions. The skip regex is tricky in that
1026it only accepts something not ending in either \015 or \012, as these are
1027required for the accept regex.
1028
1029 $handle->push_read (regex =>
1030 qr<\015\012\015\012>,
1031 undef, # no reject
1032 qr<^.*[^\015\012]>,
1033 sub { ... });
1034
1035=cut
1036
1037register_read_type regex => sub {
1038 my ($self, $cb, $accept, $reject, $skip) = @_;
1039
1040 my $data;
1041 my $rbuf = \$self->{rbuf};
674 1042
675 sub { 1043 sub {
676 $_[0]{rbuf} =~ s/$eol// or return; 1044 # accept
677 1045 if ($$rbuf =~ $accept) {
678 $cb->($_[0], $1, $2); 1046 $data .= substr $$rbuf, 0, $+[0], "";
1047 $cb->($self, $data);
1048 return 1;
1049 }
679 1 1050
1051 # reject
1052 if ($reject && $$rbuf =~ $reject) {
1053 $self->_error (&Errno::EBADMSG);
1054 }
1055
1056 # skip
1057 if ($skip && $$rbuf =~ $skip) {
1058 $data .= substr $$rbuf, 0, $+[0], "";
1059 }
1060
1061 ()
680 } 1062 }
681}; 1063};
682 1064
683# compatibility with older API
684sub push_read_line {
685 my $self = shift;
686 $self->push_read (line => @_);
687}
688
689sub unshift_read_line {
690 my $self = shift;
691 $self->unshift_read (line => @_);
692}
693
694=item netstring => $cb->($string) 1065=item netstring => $cb->($handle, $string)
695 1066
696A netstring (http://cr.yp.to/proto/netstrings.txt, this is not an endorsement). 1067A netstring (http://cr.yp.to/proto/netstrings.txt, this is not an endorsement).
697 1068
698Throws an error with C<$!> set to EBADMSG on format violations. 1069Throws an error with C<$!> set to EBADMSG on format violations.
699 1070
703 my ($self, $cb) = @_; 1074 my ($self, $cb) = @_;
704 1075
705 sub { 1076 sub {
706 unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) { 1077 unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
707 if ($_[0]{rbuf} =~ /[^0-9]/) { 1078 if ($_[0]{rbuf} =~ /[^0-9]/) {
708 $! = &Errno::EBADMSG; 1079 $self->_error (&Errno::EBADMSG);
709 $self->error;
710 } 1080 }
711 return; 1081 return;
712 } 1082 }
713 1083
714 my $len = $1; 1084 my $len = $1;
717 my $string = $_[1]; 1087 my $string = $_[1];
718 $_[0]->unshift_read (chunk => 1, sub { 1088 $_[0]->unshift_read (chunk => 1, sub {
719 if ($_[1] eq ",") { 1089 if ($_[1] eq ",") {
720 $cb->($_[0], $string); 1090 $cb->($_[0], $string);
721 } else { 1091 } else {
722 $! = &Errno::EBADMSG; 1092 $self->_error (&Errno::EBADMSG);
723 $self->error;
724 } 1093 }
725 }); 1094 });
726 }); 1095 });
727 1096
728 1 1097 1
729 } 1098 }
730}; 1099};
731 1100
1101=item packstring => $format, $cb->($handle, $string)
1102
1103An octet string prefixed with an encoded length. The encoding C<$format>
1104uses the same format as a Perl C<pack> format, but must specify a single
1105integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
1106optional C<!>, C<< < >> or C<< > >> modifier).
1107
1108For example, DNS over TCP uses a prefix of C<n> (2 octet network order),
1109EPP uses a prefix of C<N> (4 octtes).
1110
1111Example: read a block of data prefixed by its length in BER-encoded
1112format (very efficient).
1113
1114 $handle->push_read (packstring => "w", sub {
1115 my ($handle, $data) = @_;
1116 });
1117
1118=cut
1119
1120register_read_type packstring => sub {
1121 my ($self, $cb, $format) = @_;
1122
1123 sub {
1124 # when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
1125 defined (my $len = eval { unpack $format, $_[0]{rbuf} })
1126 or return;
1127
1128 $format = length pack $format, $len;
1129
1130 # bypass unshift if we already have the remaining chunk
1131 if ($format + $len <= length $_[0]{rbuf}) {
1132 my $data = substr $_[0]{rbuf}, $format, $len;
1133 substr $_[0]{rbuf}, 0, $format + $len, "";
1134 $cb->($_[0], $data);
1135 } else {
1136 # remove prefix
1137 substr $_[0]{rbuf}, 0, $format, "";
1138
1139 # read remaining chunk
1140 $_[0]->unshift_read (chunk => $len, $cb);
1141 }
1142
1143 1
1144 }
1145};
1146
1147=item json => $cb->($handle, $hash_or_arrayref)
1148
1149Reads a JSON object or array, decodes it and passes it to the
1150callback. When a parse error occurs, an C<EBADMSG> error will be raised.
1151
1152If a C<json> object was passed to the constructor, then that will be used
1153for the final decode, otherwise it will create a JSON coder expecting UTF-8.
1154
1155This read type uses the incremental parser available with JSON version
11562.09 (and JSON::XS version 2.2) and above. You have to provide a
1157dependency on your own: this module will load the JSON module, but
1158AnyEvent does not depend on it itself.
1159
1160Since JSON texts are fully self-delimiting, the C<json> read and write
1161types are an ideal simple RPC protocol: just exchange JSON datagrams. See
1162the C<json> write type description, above, for an actual example.
1163
1164=cut
1165
1166register_read_type json => sub {
1167 my ($self, $cb) = @_;
1168
1169 require JSON;
1170
1171 my $data;
1172 my $rbuf = \$self->{rbuf};
1173
1174 my $json = $self->{json} ||= JSON->new->utf8;
1175
1176 sub {
1177 my $ref = eval { $json->incr_parse ($self->{rbuf}) };
1178
1179 if ($ref) {
1180 $self->{rbuf} = $json->incr_text;
1181 $json->incr_text = "";
1182 $cb->($self, $ref);
1183
1184 1
1185 } elsif ($@) {
1186 # error case
1187 $json->incr_skip;
1188
1189 $self->{rbuf} = $json->incr_text;
1190 $json->incr_text = "";
1191
1192 $self->_error (&Errno::EBADMSG);
1193 ()
1194
1195 } else {
1196 $self->{rbuf} = "";
1197 ()
1198 }
1199 }
1200};
1201
1202=item storable => $cb->($handle, $ref)
1203
1204Deserialises a L<Storable> frozen representation as written by the
1205C<storable> write type (BER-encoded length prefix followed by nfreeze'd
1206data).
1207
1208Raises C<EBADMSG> error if the data could not be decoded.
1209
1210=cut
1211
1212register_read_type storable => sub {
1213 my ($self, $cb) = @_;
1214
1215 require Storable;
1216
1217 sub {
1218 # when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
1219 defined (my $len = eval { unpack "w", $_[0]{rbuf} })
1220 or return;
1221
1222 my $format = length pack "w", $len;
1223
1224 # bypass unshift if we already have the remaining chunk
1225 if ($format + $len <= length $_[0]{rbuf}) {
1226 my $data = substr $_[0]{rbuf}, $format, $len;
1227 substr $_[0]{rbuf}, 0, $format + $len, "";
1228 $cb->($_[0], Storable::thaw ($data));
1229 } else {
1230 # remove prefix
1231 substr $_[0]{rbuf}, 0, $format, "";
1232
1233 # read remaining chunk
1234 $_[0]->unshift_read (chunk => $len, sub {
1235 if (my $ref = eval { Storable::thaw ($_[1]) }) {
1236 $cb->($_[0], $ref);
1237 } else {
1238 $self->_error (&Errno::EBADMSG);
1239 }
1240 });
1241 }
1242
1243 1
1244 }
1245};
1246
732=back 1247=back
733 1248
734=item AnyEvent::Handle::register_read_type type => $coderef->($self, $cb, @args) 1249=item AnyEvent::Handle::register_read_type type => $coderef->($handle, $cb, @args)
735 1250
736This function (not method) lets you add your own types to C<push_read>. 1251This function (not method) lets you add your own types to C<push_read>.
737 1252
738Whenever the given C<type> is used, C<push_read> will invoke the code 1253Whenever the given C<type> is used, C<push_read> will invoke the code
739reference with the handle object, the callback and the remaining 1254reference with the handle object, the callback and the remaining
741 1256
742The code reference is supposed to return a callback (usually a closure) 1257The code reference is supposed to return a callback (usually a closure)
743that works as a plain read callback (see C<< ->push_read ($cb) >>). 1258that works as a plain read callback (see C<< ->push_read ($cb) >>).
744 1259
745It should invoke the passed callback when it is done reading (remember to 1260It should invoke the passed callback when it is done reading (remember to
746pass C<$self> as first argument as all other callbacks do that). 1261pass C<$handle> as first argument as all other callbacks do that).
747 1262
748Note that this is a function, and all types registered this way will be 1263Note that this is a function, and all types registered this way will be
749global, so try to use unique names. 1264global, so try to use unique names.
750 1265
751For examples, see the source of this module (F<perldoc -m AnyEvent::Handle>, 1266For examples, see the source of this module (F<perldoc -m AnyEvent::Handle>,
754=item $handle->stop_read 1269=item $handle->stop_read
755 1270
756=item $handle->start_read 1271=item $handle->start_read
757 1272
758In rare cases you actually do not want to read anything from the 1273In rare cases you actually do not want to read anything from the
759socket. In this case you can call C<stop_read>. Neither C<on_read> no 1274socket. In this case you can call C<stop_read>. Neither C<on_read> nor
760any queued callbacks will be executed then. To start reading again, call 1275any queued callbacks will be executed then. To start reading again, call
761C<start_read>. 1276C<start_read>.
762 1277
1278Note that AnyEvent::Handle will automatically C<start_read> for you when
1279you change the C<on_read> callback or push/unshift a read callback, and it
1280will automatically C<stop_read> for you when neither C<on_read> is set nor
1281there are any read requests in the queue.
1282
1283These methods will have no effect when in TLS mode (as TLS doesn't support
1284half-duplex connections).
1285
763=cut 1286=cut
764 1287
765sub stop_read { 1288sub stop_read {
766 my ($self) = @_; 1289 my ($self) = @_;
767 1290
768 delete $self->{rw}; 1291 delete $self->{_rw} unless $self->{tls};
769} 1292}
770 1293
771sub start_read { 1294sub start_read {
772 my ($self) = @_; 1295 my ($self) = @_;
773 1296
774 unless ($self->{rw} || $self->{eof}) { 1297 unless ($self->{_rw} || $self->{_eof}) {
775 Scalar::Util::weaken $self; 1298 Scalar::Util::weaken $self;
776 1299
777 $self->{rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub { 1300 $self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub {
778 my $rbuf = $self->{filter_r} ? \my $buf : \$self->{rbuf}; 1301 my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf});
779 my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf; 1302 my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf;
780 1303
781 if ($len > 0) { 1304 if ($len > 0) {
782 $self->{filter_r} 1305 $self->{_activity} = AnyEvent->now;
783 ? $self->{filter_r}->($self, $rbuf) 1306
784 : $self->_drain_rbuf; 1307 if ($self->{tls}) {
1308 Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf);
1309
1310 &_dotls ($self);
1311 } else {
1312 $self->_drain_rbuf unless $self->{_in_drain};
1313 }
785 1314
786 } elsif (defined $len) { 1315 } elsif (defined $len) {
787 delete $self->{rw}; 1316 delete $self->{_rw};
788 $self->{eof} = 1; 1317 $self->{_eof} = 1;
789 $self->_drain_rbuf; 1318 $self->_drain_rbuf unless $self->{_in_drain};
790 1319
791 } elsif ($! != EAGAIN && $! != EINTR) { 1320 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
792 return $self->error; 1321 return $self->_error ($!, 1);
793 } 1322 }
794 }); 1323 });
795 } 1324 }
796} 1325}
797 1326
1327# poll the write BIO and send the data if applicable
798sub _dotls { 1328sub _dotls {
799 my ($self) = @_; 1329 my ($self) = @_;
800 1330
1331 my $tmp;
1332
801 if (length $self->{tls_wbuf}) { 1333 if (length $self->{_tls_wbuf}) {
802 while ((my $len = Net::SSLeay::write ($self->{tls}, $self->{tls_wbuf})) > 0) { 1334 while (($tmp = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) {
803 substr $self->{tls_wbuf}, 0, $len, ""; 1335 substr $self->{_tls_wbuf}, 0, $tmp, "";
804 } 1336 }
805 } 1337 }
806 1338
807 if (defined (my $buf = Net::SSLeay::BIO_read ($self->{tls_wbio}))) { 1339 while (defined ($tmp = Net::SSLeay::read ($self->{tls}))) {
1340 unless (length $tmp) {
1341 # let's treat SSL-eof as we treat normal EOF
1342 delete $self->{_rw};
1343 $self->{_eof} = 1;
1344 &_freetls;
1345 }
1346
1347 $self->{rbuf} .= $tmp;
1348 $self->_drain_rbuf unless $self->{_in_drain};
1349 $self->{tls} or return; # tls session might have gone away in callback
1350 }
1351
1352 $tmp = Net::SSLeay::get_error ($self->{tls}, -1);
1353
1354 if ($tmp != Net::SSLeay::ERROR_WANT_READ ()) {
1355 if ($tmp == Net::SSLeay::ERROR_SYSCALL ()) {
1356 return $self->_error ($!, 1);
1357 } elsif ($tmp == Net::SSLeay::ERROR_SSL ()) {
1358 return $self->_error (&Errno::EIO, 1);
1359 }
1360
1361 # all other errors are fine for our purposes
1362 }
1363
1364 while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) {
808 $self->{wbuf} .= $buf; 1365 $self->{wbuf} .= $tmp;
809 $self->_drain_wbuf; 1366 $self->_drain_wbuf;
810 }
811
812 while (defined (my $buf = Net::SSLeay::read ($self->{tls}))) {
813 $self->{rbuf} .= $buf;
814 $self->_drain_rbuf;
815 }
816
817 my $err = Net::SSLeay::get_error ($self->{tls}, -1);
818
819 if ($err!= Net::SSLeay::ERROR_WANT_READ ()) {
820 if ($err == Net::SSLeay::ERROR_SYSCALL ()) {
821 $self->error;
822 } elsif ($err == Net::SSLeay::ERROR_SSL ()) {
823 $! = &Errno::EIO;
824 $self->error;
825 }
826
827 # all others are fine for our purposes
828 } 1367 }
829} 1368}
830 1369
831=item $handle->starttls ($tls[, $tls_ctx]) 1370=item $handle->starttls ($tls[, $tls_ctx])
832 1371
838C<"connect">, C<"accept"> or an existing Net::SSLeay object). 1377C<"connect">, C<"accept"> or an existing Net::SSLeay object).
839 1378
840The second argument is the optional C<Net::SSLeay::CTX> object that is 1379The second argument is the optional C<Net::SSLeay::CTX> object that is
841used when AnyEvent::Handle has to create its own TLS connection object. 1380used when AnyEvent::Handle has to create its own TLS connection object.
842 1381
843=cut 1382The TLS connection object will end up in C<< $handle->{tls} >> after this
1383call and can be used or changed to your liking. Note that the handshake
1384might have already started when this function returns.
844 1385
845# TODO: maybe document... 1386If it an error to start a TLS handshake more than once per
1387AnyEvent::Handle object (this is due to bugs in OpenSSL).
1388
1389=cut
1390
846sub starttls { 1391sub starttls {
847 my ($self, $ssl, $ctx) = @_; 1392 my ($self, $ssl, $ctx) = @_;
848 1393
849 $self->stoptls; 1394 require Net::SSLeay;
850 1395
1396 Carp::croak "it is an error to call starttls more than once on an AnyEvent::Handle object"
1397 if $self->{tls};
1398
851 if ($ssl eq "accept") { 1399 if ($ssl eq "accept") {
852 $ssl = Net::SSLeay::new ($ctx || TLS_CTX ()); 1400 $ssl = Net::SSLeay::new ($ctx || TLS_CTX ());
853 Net::SSLeay::set_accept_state ($ssl); 1401 Net::SSLeay::set_accept_state ($ssl);
854 } elsif ($ssl eq "connect") { 1402 } elsif ($ssl eq "connect") {
855 $ssl = Net::SSLeay::new ($ctx || TLS_CTX ()); 1403 $ssl = Net::SSLeay::new ($ctx || TLS_CTX ());
861 # basically, this is deep magic (because SSL_read should have the same issues) 1409 # basically, this is deep magic (because SSL_read should have the same issues)
862 # but the openssl maintainers basically said: "trust us, it just works". 1410 # but the openssl maintainers basically said: "trust us, it just works".
863 # (unfortunately, we have to hardcode constants because the abysmally misdesigned 1411 # (unfortunately, we have to hardcode constants because the abysmally misdesigned
864 # and mismaintained ssleay-module doesn't even offer them). 1412 # and mismaintained ssleay-module doesn't even offer them).
865 # http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html 1413 # http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html
1414 #
1415 # in short: this is a mess.
1416 #
1417 # note that we do not try to keep the length constant between writes as we are required to do.
1418 # we assume that most (but not all) of this insanity only applies to non-blocking cases,
1419 # and we drive openssl fully in blocking mode here. Or maybe we don't - openssl seems to
1420 # have identity issues in that area.
866 Net::SSLeay::CTX_set_mode ($self->{tls}, 1421 Net::SSLeay::CTX_set_mode ($self->{tls},
867 (eval { Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1) 1422 (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)
868 | (eval { Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2)); 1423 | (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2));
869 1424
870 $self->{tls_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); 1425 $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
871 $self->{tls_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); 1426 $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
872 1427
873 Net::SSLeay::set_bio ($ssl, $self->{tls_rbio}, $self->{tls_wbio}); 1428 Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio});
874 1429
875 $self->{filter_w} = sub { 1430 &_dotls; # need to trigger the initial handshake
876 $_[0]{tls_wbuf} .= ${$_[1]}; 1431 $self->start_read; # make sure we actually do read
877 &_dotls;
878 };
879 $self->{filter_r} = sub {
880 Net::SSLeay::BIO_write ($_[0]{tls_rbio}, ${$_[1]});
881 &_dotls;
882 };
883} 1432}
884 1433
885=item $handle->stoptls 1434=item $handle->stoptls
886 1435
887Destroys the SSL connection, if any. Partial read or write data will be 1436Shuts down the SSL connection - this makes a proper EOF handshake by
888lost. 1437sending a close notify to the other side, but since OpenSSL doesn't
1438support non-blocking shut downs, it is not possible to re-use the stream
1439afterwards.
889 1440
890=cut 1441=cut
891 1442
892sub stoptls { 1443sub stoptls {
893 my ($self) = @_; 1444 my ($self) = @_;
894 1445
1446 if ($self->{tls}) {
1447 Net::SSLeay::shutdown ($self->{tls});
1448
1449 &_dotls;
1450
1451 # we don't give a shit. no, we do, but we can't. no...
1452 # we, we... have to use openssl :/
1453 &_freetls;
1454 }
1455}
1456
1457sub _freetls {
1458 my ($self) = @_;
1459
1460 return unless $self->{tls};
1461
895 Net::SSLeay::free (delete $self->{tls}) if $self->{tls}; 1462 Net::SSLeay::free (delete $self->{tls});
896 delete $self->{tls_rbio}; 1463
897 delete $self->{tls_wbio}; 1464 delete @$self{qw(_rbio _wbio _tls_wbuf)};
898 delete $self->{tls_wbuf};
899 delete $self->{filter_r};
900 delete $self->{filter_w};
901} 1465}
902 1466
903sub DESTROY { 1467sub DESTROY {
904 my $self = shift; 1468 my $self = shift;
905 1469
906 $self->stoptls; 1470 &_freetls;
1471
1472 my $linger = exists $self->{linger} ? $self->{linger} : 3600;
1473
1474 if ($linger && length $self->{wbuf}) {
1475 my $fh = delete $self->{fh};
1476 my $wbuf = delete $self->{wbuf};
1477
1478 my @linger;
1479
1480 push @linger, AnyEvent->io (fh => $fh, poll => "w", cb => sub {
1481 my $len = syswrite $fh, $wbuf, length $wbuf;
1482
1483 if ($len > 0) {
1484 substr $wbuf, 0, $len, "";
1485 } else {
1486 @linger = (); # end
1487 }
1488 });
1489 push @linger, AnyEvent->timer (after => $linger, cb => sub {
1490 @linger = ();
1491 });
1492 }
1493}
1494
1495=item $handle->destroy
1496
1497Shuts down the handle object as much as possible - this call ensures that
1498no further callbacks will be invoked and resources will be freed as much
1499as possible. You must not call any methods on the object afterwards.
1500
1501Normally, you can just "forget" any references to an AnyEvent::Handle
1502object and it will simply shut down. This works in fatal error and EOF
1503callbacks, as well as code outside. It does I<NOT> work in a read or write
1504callback, so when you want to destroy the AnyEvent::Handle object from
1505within such an callback. You I<MUST> call C<< ->destroy >> explicitly in
1506that case.
1507
1508The handle might still linger in the background and write out remaining
1509data, as specified by the C<linger> option, however.
1510
1511=cut
1512
1513sub destroy {
1514 my ($self) = @_;
1515
1516 $self->DESTROY;
1517 %$self = ();
907} 1518}
908 1519
909=item AnyEvent::Handle::TLS_CTX 1520=item AnyEvent::Handle::TLS_CTX
910 1521
911This function creates and returns the Net::SSLeay::CTX object used by 1522This function creates and returns the Net::SSLeay::CTX object used by
941 } 1552 }
942} 1553}
943 1554
944=back 1555=back
945 1556
1557
1558=head1 NONFREQUENTLY ASKED QUESTIONS
1559
1560=over 4
1561
1562=item I C<undef> the AnyEvent::Handle reference inside my callback and
1563still get further invocations!
1564
1565That's because AnyEvent::Handle keeps a reference to itself when handling
1566read or write callbacks.
1567
1568It is only safe to "forget" the reference inside EOF or error callbacks,
1569from within all other callbacks, you need to explicitly call the C<<
1570->destroy >> method.
1571
1572=item I get different callback invocations in TLS mode/Why can't I pause
1573reading?
1574
1575Unlike, say, TCP, TLS connections do not consist of two independent
1576communication channels, one for each direction. Or put differently. The
1577read and write directions are not independent of each other: you cannot
1578write data unless you are also prepared to read, and vice versa.
1579
1580This can mean than, in TLS mode, you might get C<on_error> or C<on_eof>
1581callback invocations when you are not expecting any read data - the reason
1582is that AnyEvent::Handle always reads in TLS mode.
1583
1584During the connection, you have to make sure that you always have a
1585non-empty read-queue, or an C<on_read> watcher. At the end of the
1586connection (or when you no longer want to use it) you can call the
1587C<destroy> method.
1588
1589=item How do I read data until the other side closes the connection?
1590
1591If you just want to read your data into a perl scalar, the easiest way
1592to achieve this is by setting an C<on_read> callback that does nothing,
1593clearing the C<on_eof> callback and in the C<on_error> callback, the data
1594will be in C<$_[0]{rbuf}>:
1595
1596 $handle->on_read (sub { });
1597 $handle->on_eof (undef);
1598 $handle->on_error (sub {
1599 my $data = delete $_[0]{rbuf};
1600 undef $handle;
1601 });
1602
1603The reason to use C<on_error> is that TCP connections, due to latencies
1604and packets loss, might get closed quite violently with an error, when in
1605fact, all data has been received.
1606
1607It is usually better to use acknowledgements when transferring data,
1608to make sure the other side hasn't just died and you got the data
1609intact. This is also one reason why so many internet protocols have an
1610explicit QUIT command.
1611
1612=item I don't want to destroy the handle too early - how do I wait until
1613all data has been written?
1614
1615After writing your last bits of data, set the C<on_drain> callback
1616and destroy the handle in there - with the default setting of
1617C<low_water_mark> this will be called precisely when all data has been
1618written to the socket:
1619
1620 $handle->push_write (...);
1621 $handle->on_drain (sub {
1622 warn "all data submitted to the kernel\n";
1623 undef $handle;
1624 });
1625
1626=back
1627
1628
1629=head1 SUBCLASSING AnyEvent::Handle
1630
1631In many cases, you might want to subclass AnyEvent::Handle.
1632
1633To make this easier, a given version of AnyEvent::Handle uses these
1634conventions:
1635
1636=over 4
1637
1638=item * all constructor arguments become object members.
1639
1640At least initially, when you pass a C<tls>-argument to the constructor it
1641will end up in C<< $handle->{tls} >>. Those members might be changed or
1642mutated later on (for example C<tls> will hold the TLS connection object).
1643
1644=item * other object member names are prefixed with an C<_>.
1645
1646All object members not explicitly documented (internal use) are prefixed
1647with an underscore character, so the remaining non-C<_>-namespace is free
1648for use for subclasses.
1649
1650=item * all members not documented here and not prefixed with an underscore
1651are free to use in subclasses.
1652
1653Of course, new versions of AnyEvent::Handle may introduce more "public"
1654member variables, but thats just life, at least it is documented.
1655
1656=back
1657
946=head1 AUTHOR 1658=head1 AUTHOR
947 1659
948Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>. 1660Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>.
949 1661
950=cut 1662=cut

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