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Revision 1.38 by root, Mon May 26 21:28:33 2008 UTC vs.
Revision 1.115 by root, Tue Feb 10 13:58:49 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 qw(WSAWOULDBLOCK); 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
17=cut 17=cut
18 18
19our $VERSION = '0.04'; 19our $VERSION = 4.331;
20 20
21=head1 SYNOPSIS 21=head1 SYNOPSIS
22 22
23 use AnyEvent; 23 use AnyEvent;
24 use AnyEvent::Handle; 24 use AnyEvent::Handle;
27 27
28 my $handle = 28 my $handle =
29 AnyEvent::Handle->new ( 29 AnyEvent::Handle->new (
30 fh => \*STDIN, 30 fh => \*STDIN,
31 on_eof => sub { 31 on_eof => sub {
32 $cv->broadcast; 32 $cv->send;
33 }, 33 },
34 ); 34 );
35 35
36 # send some request line 36 # send some request line
37 $handle->push_write ("getinfo\015\012"); 37 $handle->push_write ("getinfo\015\012");
49 49
50This 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
51filehandles. For utility functions for doing non-blocking connects and accepts 51filehandles. For utility functions for doing non-blocking connects and accepts
52on sockets see L<AnyEvent::Util>. 52on sockets see L<AnyEvent::Util>.
53 53
54The L<AnyEvent::Intro> tutorial contains some well-documented
55AnyEvent::Handle examples.
56
54In the following, when the documentation refers to of "bytes" then this 57In the following, when the documentation refers to of "bytes" then this
55means 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
56treatment of characters applies to this module as well. 59treatment of characters applies to this module as well.
57 60
58All callbacks will be invoked with the handle object as their first 61All callbacks will be invoked with the handle object as their first
70 73
71=item fh => $filehandle [MANDATORY] 74=item fh => $filehandle [MANDATORY]
72 75
73The filehandle this L<AnyEvent::Handle> object will operate on. 76The filehandle this L<AnyEvent::Handle> object will operate on.
74 77
75NOTE: The filehandle will be set to non-blocking (using 78NOTE: The filehandle will be set to non-blocking mode (using
76AnyEvent::Util::fh_nonblocking). 79C<AnyEvent::Util::fh_nonblocking>) by the constructor and needs to stay in
80that mode.
77 81
78=item on_eof => $cb->($self) 82=item on_eof => $cb->($handle)
79 83
80Set 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.
81 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
82While not mandatory, it is highly recommended to set an eof callback, 93While not mandatory, it is I<highly> recommended to set an EOF callback,
83otherwise 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
84waiting for data. 95waiting for data.
85 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
86=item on_error => $cb->($self) 100=item on_error => $cb->($handle, $fatal)
87 101
88This is the fatal error callback, that is called when, well, a fatal error 102This is the error callback, which is called when, well, some error
89occurs, such as not being able to resolve the hostname, failure to connect 103occured, such as not being able to resolve the hostname, failure to
90or a read error. 104connect or a read error.
91 105
92The object will not be in a usable state when this callback has been 106Some errors are fatal (which is indicated by C<$fatal> being true). On
93called. 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>).
94 116
95On callback entrance, the value of C<$!> contains the operating system 117On callback entrance, the value of C<$!> contains the operating system
96error (or C<ENOSPC>, C<EPIPE> or C<EBADMSG>). 118error (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT> or C<EBADMSG>).
97
98The callback should throw an exception. If it returns, then
99AnyEvent::Handle will C<croak> for you.
100 119
101While 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
102you will not be notified of errors otherwise. The default simply calls 121you will not be notified of errors otherwise. The default simply calls
103die. 122C<croak>.
104 123
105=item on_read => $cb->($self) 124=item on_read => $cb->($handle)
106 125
107This sets the default read callback, which is called when data arrives 126This sets the default read callback, which is called when data arrives
108and 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).
109 130
110To 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 >>
111method or access the C<$self->{rbuf}> member directly. 132method or access the C<$handle->{rbuf}> member directly.
112 133
113When 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
114feed 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
115calling 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
116error will be raised (with C<$!> set to C<EPIPE>). 137error will be raised (with C<$!> set to C<EPIPE>).
117 138
118=item on_drain => $cb->() 139=item on_drain => $cb->($handle)
119 140
120This 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
121(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).
122 143
123To append to the write buffer, use the C<< ->push_write >> method. 144To append to the write buffer, use the C<< ->push_write >> method.
124 145
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
125=item rbuf_max => <bytes> 173=item rbuf_max => <bytes>
126 174
127If 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>)
128when 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
129avoid denial-of-service attacks. 177avoid some forms of denial-of-service attacks.
130 178
131For example, a server accepting connections from untrusted sources should 179For example, a server accepting connections from untrusted sources should
132be 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
133(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
134amount 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
135isn't finished). 183isn't finished).
136 184
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
137=item read_size => <bytes> 211=item read_size => <bytes>
138 212
139The 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
140on each [loop iteration). Default: C<4096>. 214try to read during each loop iteration, which affects memory
215requirements). Default: C<8192>.
141 216
142=item low_water_mark => <bytes> 217=item low_water_mark => <bytes>
143 218
144Sets 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
145buffer: 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
146considered empty. 221considered empty.
147 222
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
148=item tls => "accept" | "connect" | Net::SSLeay::SSL object 240=item tls => "accept" | "connect" | Net::SSLeay::SSL object
149 241
150When this parameter is given, it enables TLS (SSL) mode, that means it 242When this parameter is given, it enables TLS (SSL) mode, that means
151will start making tls handshake and will transparently encrypt/decrypt 243AnyEvent will start a TLS handshake as soon as the conenction has been
152data. 244established and will transparently encrypt/decrypt data afterwards.
153 245
154TLS mode requires Net::SSLeay to be installed (it will be loaded 246TLS mode requires Net::SSLeay to be installed (it will be loaded
155automatically 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.
156 250
157For 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
158connection, use C<connect> mode. 252C<accept>, and for the TLS client side of a connection, use C<connect>
253mode.
159 254
160You can also provide your own TLS connection object, but you have 255You can also provide your own TLS connection object, but you have
161to 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>
162or 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
163AnyEvent::Handle. 258AnyEvent::Handle.
164 259
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
165See 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.
166 266
167=item tls_ctx => $ssl_ctx 267=item tls_ctx => $ssl_ctx
168 268
169Use 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
170(unless a connection object was specified directly). If this parameter is 270(unless a connection object was specified directly). If this parameter is
171missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>. 271missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>.
172 272
173=item filter_r => $cb 273=item json => JSON or JSON::XS object
174 274
175=item filter_w => $cb 275This is the json coder object used by the C<json> read and write types.
176 276
177These exist, but are undocumented at this time. 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.
178 283
179=back 284=back
180 285
181=cut 286=cut
182 287
187 292
188 $self->{fh} or Carp::croak "mandatory argument fh is missing"; 293 $self->{fh} or Carp::croak "mandatory argument fh is missing";
189 294
190 AnyEvent::Util::fh_nonblocking $self->{fh}, 1; 295 AnyEvent::Util::fh_nonblocking $self->{fh}, 1;
191 296
192 if ($self->{tls}) {
193 require Net::SSLeay;
194 $self->starttls (delete $self->{tls}, delete $self->{tls_ctx}); 297 $self->starttls (delete $self->{tls}, delete $self->{tls_ctx})
195 } 298 if $self->{tls};
196 299
197 $self->on_eof (delete $self->{on_eof} ) if $self->{on_eof}; 300 $self->{_activity} = AnyEvent->now;
198 $self->on_error (delete $self->{on_error}) if $self->{on_error}; 301 $self->_timeout;
302
199 $self->on_drain (delete $self->{on_drain}) if $self->{on_drain}; 303 $self->on_drain (delete $self->{on_drain}) if exists $self->{on_drain};
200 $self->on_read (delete $self->{on_read} ) if $self->{on_read}; 304 $self->no_delay (delete $self->{no_delay}) if exists $self->{no_delay};
201 305
202 $self->start_read; 306 $self->start_read
307 if $self->{on_read};
203 308
204 $self 309 $self
205} 310}
206 311
207sub _shutdown { 312sub _shutdown {
208 my ($self) = @_; 313 my ($self) = @_;
209 314
315 delete $self->{_tw};
210 delete $self->{_rw}; 316 delete $self->{_rw};
211 delete $self->{_ww}; 317 delete $self->{_ww};
212 delete $self->{fh}; 318 delete $self->{fh};
213}
214 319
320 &_freetls;
321
322 delete $self->{on_read};
323 delete $self->{_queue};
324}
325
215sub error { 326sub _error {
216 my ($self) = @_; 327 my ($self, $errno, $fatal) = @_;
217 328
218 {
219 local $!;
220 $self->_shutdown; 329 $self->_shutdown
221 } 330 if $fatal;
222 331
223 $self->{on_error}($self) 332 $! = $errno;
333
224 if $self->{on_error}; 334 if ($self->{on_error}) {
225 335 $self->{on_error}($self, $fatal);
336 } elsif ($self->{fh}) {
226 Carp::croak "AnyEvent::Handle uncaught fatal error: $!"; 337 Carp::croak "AnyEvent::Handle uncaught error: $!";
338 }
227} 339}
228 340
229=item $fh = $handle->fh 341=item $fh = $handle->fh
230 342
231This 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.
232 344
233=cut 345=cut
234 346
235sub fh { $_[0]{fh} } 347sub fh { $_[0]{fh} }
236 348
252 364
253sub on_eof { 365sub on_eof {
254 $_[0]{on_eof} = $_[1]; 366 $_[0]{on_eof} = $_[1];
255} 367}
256 368
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 $self->{_tw};
460 }
461}
462
257############################################################################# 463#############################################################################
258 464
259=back 465=back
260 466
261=head2 WRITE QUEUE 467=head2 WRITE QUEUE
282 my ($self, $cb) = @_; 488 my ($self, $cb) = @_;
283 489
284 $self->{on_drain} = $cb; 490 $self->{on_drain} = $cb;
285 491
286 $cb->($self) 492 $cb->($self)
287 if $cb && $self->{low_water_mark} >= length $self->{wbuf}; 493 if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf});
288} 494}
289 495
290=item $handle->push_write ($data) 496=item $handle->push_write ($data)
291 497
292Queues 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
306 my $len = syswrite $self->{fh}, $self->{wbuf}; 512 my $len = syswrite $self->{fh}, $self->{wbuf};
307 513
308 if ($len >= 0) { 514 if ($len >= 0) {
309 substr $self->{wbuf}, 0, $len, ""; 515 substr $self->{wbuf}, 0, $len, "";
310 516
517 $self->{_activity} = AnyEvent->now;
518
311 $self->{on_drain}($self) 519 $self->{on_drain}($self)
312 if $self->{low_water_mark} >= length $self->{wbuf} 520 if $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf})
313 && $self->{on_drain}; 521 && $self->{on_drain};
314 522
315 delete $self->{_ww} unless length $self->{wbuf}; 523 delete $self->{_ww} unless length $self->{wbuf};
316 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAWOULDBLOCK) { 524 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
317 $self->error; 525 $self->_error ($!, 1);
318 } 526 }
319 }; 527 };
320 528
321 # try to write data immediately 529 # try to write data immediately
322 $cb->(); 530 $cb->() unless $self->{autocork};
323 531
324 # if still data left in wbuf, we need to poll 532 # if still data left in wbuf, we need to poll
325 $self->{_ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb) 533 $self->{_ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb)
326 if length $self->{wbuf}; 534 if length $self->{wbuf};
327 }; 535 };
341 549
342 @_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write") 550 @_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write")
343 ->($self, @_); 551 ->($self, @_);
344 } 552 }
345 553
346 if ($self->{filter_w}) { 554 if ($self->{tls}) {
347 $self->{filter_w}->($self, \$_[0]); 555 $self->{_tls_wbuf} .= $_[0];
556
557 &_dotls ($self);
348 } else { 558 } else {
349 $self->{wbuf} .= $_[0]; 559 $self->{wbuf} .= $_[0];
350 $self->_drain_wbuf; 560 $self->_drain_wbuf;
351 } 561 }
352} 562}
353 563
354=item $handle->push_write (type => @args) 564=item $handle->push_write (type => @args)
355 565
356=item $handle->unshift_write (type => @args)
357
358Instead 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
359the job by specifying a type and type-specific arguments. 567the job by specifying a type and type-specific arguments.
360 568
361Predefined 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
362drop by and tell us): 570drop by and tell us):
366=item netstring => $string 574=item netstring => $string
367 575
368Formats the given value as netstring 576Formats the given value as netstring
369(http://cr.yp.to/proto/netstrings.txt, this is not a recommendation to use them). 577(http://cr.yp.to/proto/netstrings.txt, this is not a recommendation to use them).
370 578
371=back
372
373=cut 579=cut
374 580
375register_write_type netstring => sub { 581register_write_type netstring => sub {
376 my ($self, $string) = @_; 582 my ($self, $string) = @_;
377 583
378 sprintf "%d:%s,", (length $string), $string 584 (length $string) . ":$string,"
379}; 585};
380 586
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
381=item AnyEvent::Handle::register_write_type type => $coderef->($self, @args) 660=item AnyEvent::Handle::register_write_type type => $coderef->($handle, @args)
382 661
383This 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>.
384Whenever 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
385reference with the handle object and the remaining arguments. 664reference with the handle object and the remaining arguments.
386 665
405ways, 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
406a queue. 685a queue.
407 686
408In 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
409new 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
410enough 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
411or not. 690leave the data there if you want to accumulate more (e.g. when only a
691partial message has been received so far).
412 692
413In 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
414case, AnyEvent::Handle will call the first queued callback each time new 694case, AnyEvent::Handle will call the first queued callback each time new
415data 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
416below). 696done its job (see C<push_read>, below).
417 697
418This 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
419a chunk of data, and AnyEvent::Handle will execute them in order. 699a chunk of data, and AnyEvent::Handle will execute them in order.
420 700
421Example 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
422the specified number of bytes which give an XML datagram. 702the specified number of bytes which give an XML datagram.
423 703
424 # in the default state, expect some header bytes 704 # in the default state, expect some header bytes
425 $handle->on_read (sub { 705 $handle->on_read (sub {
426 # 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)
427 shift->unshift_read_chunk (4, sub { 707 shift->unshift_read (chunk => 4, sub {
428 # header arrived, decode 708 # header arrived, decode
429 my $len = unpack "N", $_[1]; 709 my $len = unpack "N", $_[1];
430 710
431 # now read the payload 711 # now read the payload
432 shift->unshift_read_chunk ($len, sub { 712 shift->unshift_read (chunk => $len, sub {
433 my $xml = $_[1]; 713 my $xml = $_[1];
434 # handle xml 714 # handle xml
435 }); 715 });
436 }); 716 });
437 }); 717 });
438 718
439Example 2: Implement a client for a protocol that replies either with 719Example 2: Implement a client for a protocol that replies either with "OK"
440"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
441second 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
442pipeline sending both requests and manipulate the queue as necessary in 722just pipeline sending both requests and manipulate the queue as necessary
443the callbacks: 723in the callbacks.
444 724
445 # 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"
446 $handle->push_write ("request 1\015\012"); 730 $handle->push_write ("request 1\015\012");
447 731
448 # 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
449 $handle->push_read_line (sub { 733 $handle->push_read (line => sub {
450 # if we got an "OK", we have to _prepend_ another line, 734 # if we got an "OK", we have to _prepend_ another line,
451 # so it will be read before the second request reads its 64 bytes 735 # so it will be read before the second request reads its 64 bytes
452 # which are already in the queue when this callback is called 736 # which are already in the queue when this callback is called
453 # we don't do this in case we got an error 737 # we don't do this in case we got an error
454 if ($_[1] eq "OK") { 738 if ($_[1] eq "OK") {
455 $_[0]->unshift_read_line (sub { 739 $_[0]->unshift_read (line => sub {
456 my $response = $_[1]; 740 my $response = $_[1];
457 ... 741 ...
458 }); 742 });
459 } 743 }
460 }); 744 });
461 745
462 # request two 746 # request two, simply returns 64 octets
463 $handle->push_write ("request 2\015\012"); 747 $handle->push_write ("request 2\015\012");
464 748
465 # simply read 64 bytes, always 749 # simply read 64 bytes, always
466 $handle->push_read_chunk (64, sub { 750 $handle->push_read (chunk => 64, sub {
467 my $response = $_[1]; 751 my $response = $_[1];
468 ... 752 ...
469 }); 753 });
470 754
471=over 4 755=over 4
472 756
473=cut 757=cut
474 758
475sub _drain_rbuf { 759sub _drain_rbuf {
476 my ($self) = @_; 760 my ($self) = @_;
761
762 local $self->{_in_drain} = 1;
477 763
478 if ( 764 if (
479 defined $self->{rbuf_max} 765 defined $self->{rbuf_max}
480 && $self->{rbuf_max} < length $self->{rbuf} 766 && $self->{rbuf_max} < length $self->{rbuf}
481 ) { 767 ) {
482 $! = &Errno::ENOSPC; 768 $self->_error (&Errno::ENOSPC, 1), return;
483 $self->error;
484 } 769 }
485 770
486 return if $self->{in_drain}; 771 while () {
487 local $self->{in_drain} = 1; 772 $self->{rbuf} .= delete $self->{tls_rbuf} if exists $self->{tls_rbuf};#d#
488 773
489 while (my $len = length $self->{rbuf}) { 774 my $len = length $self->{rbuf};
490 no strict 'refs'; 775
491 if (my $cb = shift @{ $self->{_queue} }) { 776 if (my $cb = shift @{ $self->{_queue} }) {
492 unless ($cb->($self)) { 777 unless ($cb->($self)) {
493 if ($self->{_eof}) { 778 if ($self->{_eof}) {
494 # no progress can be made (not enough data and no data forthcoming) 779 # no progress can be made (not enough data and no data forthcoming)
495 $! = &Errno::EPIPE; 780 $self->_error (&Errno::EPIPE, 1), return;
496 $self->error;
497 } 781 }
498 782
499 unshift @{ $self->{_queue} }, $cb; 783 unshift @{ $self->{_queue} }, $cb;
500 return; 784 last;
501 } 785 }
502 } elsif ($self->{on_read}) { 786 } elsif ($self->{on_read}) {
787 last unless $len;
788
503 $self->{on_read}($self); 789 $self->{on_read}($self);
504 790
505 if ( 791 if (
506 $self->{_eof} # if no further data will arrive
507 && $len == length $self->{rbuf} # and no data has been consumed 792 $len == length $self->{rbuf} # if no data has been consumed
508 && !@{ $self->{_queue} } # and the queue is still empty 793 && !@{ $self->{_queue} } # and the queue is still empty
509 && $self->{on_read} # and we still want to read data 794 && $self->{on_read} # but we still have on_read
510 ) { 795 ) {
796 # no further data will arrive
511 # then no progress can be made 797 # so no progress can be made
512 $! = &Errno::EPIPE; 798 $self->_error (&Errno::EPIPE, 1), return
513 $self->error; 799 if $self->{_eof};
800
801 last; # more data might arrive
514 } 802 }
515 } else { 803 } else {
516 # read side becomes idle 804 # read side becomes idle
517 delete $self->{_rw}; 805 delete $self->{_rw} unless $self->{tls};
518 return; 806 last;
519 } 807 }
520 } 808 }
521 809
522 if ($self->{_eof}) { 810 if ($self->{_eof}) {
523 $self->_shutdown; 811 if ($self->{on_eof}) {
524 $self->{on_eof}($self) 812 $self->{on_eof}($self)
525 if $self->{on_eof}; 813 } else {
814 $self->_error (0, 1);
815 }
816 }
817
818 # may need to restart read watcher
819 unless ($self->{_rw}) {
820 $self->start_read
821 if $self->{on_read} || @{ $self->{_queue} };
526 } 822 }
527} 823}
528 824
529=item $handle->on_read ($cb) 825=item $handle->on_read ($cb)
530 826
536 832
537sub on_read { 833sub on_read {
538 my ($self, $cb) = @_; 834 my ($self, $cb) = @_;
539 835
540 $self->{on_read} = $cb; 836 $self->{on_read} = $cb;
837 $self->_drain_rbuf if $cb && !$self->{_in_drain};
541} 838}
542 839
543=item $handle->rbuf 840=item $handle->rbuf
544 841
545Returns the read buffer (as a modifiable lvalue). 842Returns the read buffer (as a modifiable lvalue).
594 $cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_read") 891 $cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_read")
595 ->($self, $cb, @_); 892 ->($self, $cb, @_);
596 } 893 }
597 894
598 push @{ $self->{_queue} }, $cb; 895 push @{ $self->{_queue} }, $cb;
599 $self->_drain_rbuf; 896 $self->_drain_rbuf unless $self->{_in_drain};
600} 897}
601 898
602sub unshift_read { 899sub unshift_read {
603 my $self = shift; 900 my $self = shift;
604 my $cb = pop; 901 my $cb = pop;
610 ->($self, $cb, @_); 907 ->($self, $cb, @_);
611 } 908 }
612 909
613 910
614 unshift @{ $self->{_queue} }, $cb; 911 unshift @{ $self->{_queue} }, $cb;
615 $self->_drain_rbuf; 912 $self->_drain_rbuf unless $self->{_in_drain};
616} 913}
617 914
618=item $handle->push_read (type => @args, $cb) 915=item $handle->push_read (type => @args, $cb)
619 916
620=item $handle->unshift_read (type => @args, $cb) 917=item $handle->unshift_read (type => @args, $cb)
626Predefined types are (if you have ideas for additional types, feel free to 923Predefined types are (if you have ideas for additional types, feel free to
627drop by and tell us): 924drop by and tell us):
628 925
629=over 4 926=over 4
630 927
631=item chunk => $octets, $cb->($self, $data) 928=item chunk => $octets, $cb->($handle, $data)
632 929
633Invoke the callback only once C<$octets> bytes have been read. Pass the 930Invoke the callback only once C<$octets> bytes have been read. Pass the
634data read to the callback. The callback will never be called with less 931data read to the callback. The callback will never be called with less
635data. 932data.
636 933
650 $cb->($_[0], substr $_[0]{rbuf}, 0, $len, ""); 947 $cb->($_[0], substr $_[0]{rbuf}, 0, $len, "");
651 1 948 1
652 } 949 }
653}; 950};
654 951
655# compatibility with older API
656sub push_read_chunk {
657 $_[0]->push_read (chunk => $_[1], $_[2]);
658}
659
660sub unshift_read_chunk {
661 $_[0]->unshift_read (chunk => $_[1], $_[2]);
662}
663
664=item line => [$eol, ]$cb->($self, $line, $eol) 952=item line => [$eol, ]$cb->($handle, $line, $eol)
665 953
666The callback will be called only once a full line (including the end of 954The callback will be called only once a full line (including the end of
667line marker, C<$eol>) has been read. This line (excluding the end of line 955line marker, C<$eol>) has been read. This line (excluding the end of line
668marker) will be passed to the callback as second argument (C<$line>), and 956marker) will be passed to the callback as second argument (C<$line>), and
669the end of line marker as the third argument (C<$eol>). 957the end of line marker as the third argument (C<$eol>).
683=cut 971=cut
684 972
685register_read_type line => sub { 973register_read_type line => sub {
686 my ($self, $cb, $eol) = @_; 974 my ($self, $cb, $eol) = @_;
687 975
688 $eol = qr|(\015?\012)| if @_ < 3; 976 if (@_ < 3) {
977 # this is more than twice as fast as the generic code below
978 sub {
979 $_[0]{rbuf} =~ s/^([^\015\012]*)(\015?\012)// or return;
980
981 $cb->($_[0], $1, $2);
982 1
983 }
984 } else {
689 $eol = quotemeta $eol unless ref $eol; 985 $eol = quotemeta $eol unless ref $eol;
690 $eol = qr|^(.*?)($eol)|s; 986 $eol = qr|^(.*?)($eol)|s;
691 987
692 sub { 988 sub {
693 $_[0]{rbuf} =~ s/$eol// or return; 989 $_[0]{rbuf} =~ s/$eol// or return;
694 990
695 $cb->($_[0], $1, $2); 991 $cb->($_[0], $1, $2);
992 1
696 1 993 }
697 } 994 }
698}; 995};
699 996
700# compatibility with older API
701sub push_read_line {
702 my $self = shift;
703 $self->push_read (line => @_);
704}
705
706sub unshift_read_line {
707 my $self = shift;
708 $self->unshift_read (line => @_);
709}
710
711=item netstring => $cb->($string)
712
713A netstring (http://cr.yp.to/proto/netstrings.txt, this is not an endorsement).
714
715Throws an error with C<$!> set to EBADMSG on format violations.
716
717=cut
718
719register_read_type netstring => sub {
720 my ($self, $cb) = @_;
721
722 sub {
723 unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
724 if ($_[0]{rbuf} =~ /[^0-9]/) {
725 $! = &Errno::EBADMSG;
726 $self->error;
727 }
728 return;
729 }
730
731 my $len = $1;
732
733 $self->unshift_read (chunk => $len, sub {
734 my $string = $_[1];
735 $_[0]->unshift_read (chunk => 1, sub {
736 if ($_[1] eq ",") {
737 $cb->($_[0], $string);
738 } else {
739 $! = &Errno::EBADMSG;
740 $self->error;
741 }
742 });
743 });
744
745 1
746 }
747};
748
749=item regex => $accept[, $reject[, $skip], $cb->($data) 997=item regex => $accept[, $reject[, $skip], $cb->($handle, $data)
750 998
751Makes a regex match against the regex object C<$accept> and returns 999Makes a regex match against the regex object C<$accept> and returns
752everything up to and including the match. 1000everything up to and including the match.
753 1001
754Example: read a single line terminated by '\n'. 1002Example: read a single line terminated by '\n'.
802 return 1; 1050 return 1;
803 } 1051 }
804 1052
805 # reject 1053 # reject
806 if ($reject && $$rbuf =~ $reject) { 1054 if ($reject && $$rbuf =~ $reject) {
807 $! = &Errno::EBADMSG; 1055 $self->_error (&Errno::EBADMSG);
808 $self->error;
809 } 1056 }
810 1057
811 # skip 1058 # skip
812 if ($skip && $$rbuf =~ $skip) { 1059 if ($skip && $$rbuf =~ $skip) {
813 $data .= substr $$rbuf, 0, $+[0], ""; 1060 $data .= substr $$rbuf, 0, $+[0], "";
815 1062
816 () 1063 ()
817 } 1064 }
818}; 1065};
819 1066
1067=item netstring => $cb->($handle, $string)
1068
1069A netstring (http://cr.yp.to/proto/netstrings.txt, this is not an endorsement).
1070
1071Throws an error with C<$!> set to EBADMSG on format violations.
1072
1073=cut
1074
1075register_read_type netstring => sub {
1076 my ($self, $cb) = @_;
1077
1078 sub {
1079 unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
1080 if ($_[0]{rbuf} =~ /[^0-9]/) {
1081 $self->_error (&Errno::EBADMSG);
1082 }
1083 return;
1084 }
1085
1086 my $len = $1;
1087
1088 $self->unshift_read (chunk => $len, sub {
1089 my $string = $_[1];
1090 $_[0]->unshift_read (chunk => 1, sub {
1091 if ($_[1] eq ",") {
1092 $cb->($_[0], $string);
1093 } else {
1094 $self->_error (&Errno::EBADMSG);
1095 }
1096 });
1097 });
1098
1099 1
1100 }
1101};
1102
1103=item packstring => $format, $cb->($handle, $string)
1104
1105An octet string prefixed with an encoded length. The encoding C<$format>
1106uses the same format as a Perl C<pack> format, but must specify a single
1107integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
1108optional C<!>, C<< < >> or C<< > >> modifier).
1109
1110For example, DNS over TCP uses a prefix of C<n> (2 octet network order),
1111EPP uses a prefix of C<N> (4 octtes).
1112
1113Example: read a block of data prefixed by its length in BER-encoded
1114format (very efficient).
1115
1116 $handle->push_read (packstring => "w", sub {
1117 my ($handle, $data) = @_;
1118 });
1119
1120=cut
1121
1122register_read_type packstring => sub {
1123 my ($self, $cb, $format) = @_;
1124
1125 sub {
1126 # when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
1127 defined (my $len = eval { unpack $format, $_[0]{rbuf} })
1128 or return;
1129
1130 $format = length pack $format, $len;
1131
1132 # bypass unshift if we already have the remaining chunk
1133 if ($format + $len <= length $_[0]{rbuf}) {
1134 my $data = substr $_[0]{rbuf}, $format, $len;
1135 substr $_[0]{rbuf}, 0, $format + $len, "";
1136 $cb->($_[0], $data);
1137 } else {
1138 # remove prefix
1139 substr $_[0]{rbuf}, 0, $format, "";
1140
1141 # read remaining chunk
1142 $_[0]->unshift_read (chunk => $len, $cb);
1143 }
1144
1145 1
1146 }
1147};
1148
1149=item json => $cb->($handle, $hash_or_arrayref)
1150
1151Reads a JSON object or array, decodes it and passes it to the
1152callback. When a parse error occurs, an C<EBADMSG> error will be raised.
1153
1154If a C<json> object was passed to the constructor, then that will be used
1155for the final decode, otherwise it will create a JSON coder expecting UTF-8.
1156
1157This read type uses the incremental parser available with JSON version
11582.09 (and JSON::XS version 2.2) and above. You have to provide a
1159dependency on your own: this module will load the JSON module, but
1160AnyEvent does not depend on it itself.
1161
1162Since JSON texts are fully self-delimiting, the C<json> read and write
1163types are an ideal simple RPC protocol: just exchange JSON datagrams. See
1164the C<json> write type description, above, for an actual example.
1165
1166=cut
1167
1168register_read_type json => sub {
1169 my ($self, $cb) = @_;
1170
1171 require JSON;
1172
1173 my $data;
1174 my $rbuf = \$self->{rbuf};
1175
1176 my $json = $self->{json} ||= JSON->new->utf8;
1177
1178 sub {
1179 my $ref = eval { $json->incr_parse ($self->{rbuf}) };
1180
1181 if ($ref) {
1182 $self->{rbuf} = $json->incr_text;
1183 $json->incr_text = "";
1184 $cb->($self, $ref);
1185
1186 1
1187 } elsif ($@) {
1188 # error case
1189 $json->incr_skip;
1190
1191 $self->{rbuf} = $json->incr_text;
1192 $json->incr_text = "";
1193
1194 $self->_error (&Errno::EBADMSG);
1195
1196 ()
1197 } else {
1198 $self->{rbuf} = "";
1199
1200 ()
1201 }
1202 }
1203};
1204
1205=item storable => $cb->($handle, $ref)
1206
1207Deserialises a L<Storable> frozen representation as written by the
1208C<storable> write type (BER-encoded length prefix followed by nfreeze'd
1209data).
1210
1211Raises C<EBADMSG> error if the data could not be decoded.
1212
1213=cut
1214
1215register_read_type storable => sub {
1216 my ($self, $cb) = @_;
1217
1218 require Storable;
1219
1220 sub {
1221 # when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
1222 defined (my $len = eval { unpack "w", $_[0]{rbuf} })
1223 or return;
1224
1225 my $format = length pack "w", $len;
1226
1227 # bypass unshift if we already have the remaining chunk
1228 if ($format + $len <= length $_[0]{rbuf}) {
1229 my $data = substr $_[0]{rbuf}, $format, $len;
1230 substr $_[0]{rbuf}, 0, $format + $len, "";
1231 $cb->($_[0], Storable::thaw ($data));
1232 } else {
1233 # remove prefix
1234 substr $_[0]{rbuf}, 0, $format, "";
1235
1236 # read remaining chunk
1237 $_[0]->unshift_read (chunk => $len, sub {
1238 if (my $ref = eval { Storable::thaw ($_[1]) }) {
1239 $cb->($_[0], $ref);
1240 } else {
1241 $self->_error (&Errno::EBADMSG);
1242 }
1243 });
1244 }
1245
1246 1
1247 }
1248};
1249
820=back 1250=back
821 1251
822=item AnyEvent::Handle::register_read_type type => $coderef->($self, $cb, @args) 1252=item AnyEvent::Handle::register_read_type type => $coderef->($handle, $cb, @args)
823 1253
824This function (not method) lets you add your own types to C<push_read>. 1254This function (not method) lets you add your own types to C<push_read>.
825 1255
826Whenever the given C<type> is used, C<push_read> will invoke the code 1256Whenever the given C<type> is used, C<push_read> will invoke the code
827reference with the handle object, the callback and the remaining 1257reference with the handle object, the callback and the remaining
829 1259
830The code reference is supposed to return a callback (usually a closure) 1260The code reference is supposed to return a callback (usually a closure)
831that works as a plain read callback (see C<< ->push_read ($cb) >>). 1261that works as a plain read callback (see C<< ->push_read ($cb) >>).
832 1262
833It should invoke the passed callback when it is done reading (remember to 1263It should invoke the passed callback when it is done reading (remember to
834pass C<$self> as first argument as all other callbacks do that). 1264pass C<$handle> as first argument as all other callbacks do that).
835 1265
836Note that this is a function, and all types registered this way will be 1266Note that this is a function, and all types registered this way will be
837global, so try to use unique names. 1267global, so try to use unique names.
838 1268
839For examples, see the source of this module (F<perldoc -m AnyEvent::Handle>, 1269For examples, see the source of this module (F<perldoc -m AnyEvent::Handle>,
842=item $handle->stop_read 1272=item $handle->stop_read
843 1273
844=item $handle->start_read 1274=item $handle->start_read
845 1275
846In rare cases you actually do not want to read anything from the 1276In rare cases you actually do not want to read anything from the
847socket. In this case you can call C<stop_read>. Neither C<on_read> no 1277socket. In this case you can call C<stop_read>. Neither C<on_read> nor
848any queued callbacks will be executed then. To start reading again, call 1278any queued callbacks will be executed then. To start reading again, call
849C<start_read>. 1279C<start_read>.
850 1280
1281Note that AnyEvent::Handle will automatically C<start_read> for you when
1282you change the C<on_read> callback or push/unshift a read callback, and it
1283will automatically C<stop_read> for you when neither C<on_read> is set nor
1284there are any read requests in the queue.
1285
1286These methods will have no effect when in TLS mode (as TLS doesn't support
1287half-duplex connections).
1288
851=cut 1289=cut
852 1290
853sub stop_read { 1291sub stop_read {
854 my ($self) = @_; 1292 my ($self) = @_;
855 1293
856 delete $self->{_rw}; 1294 delete $self->{_rw} unless $self->{tls};
857} 1295}
858 1296
859sub start_read { 1297sub start_read {
860 my ($self) = @_; 1298 my ($self) = @_;
861 1299
862 unless ($self->{_rw} || $self->{_eof}) { 1300 unless ($self->{_rw} || $self->{_eof}) {
863 Scalar::Util::weaken $self; 1301 Scalar::Util::weaken $self;
864 1302
865 $self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub { 1303 $self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub {
866 my $rbuf = $self->{filter_r} ? \my $buf : \$self->{rbuf}; 1304 my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf});
867 my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf; 1305 my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf;
868 1306
869 if ($len > 0) { 1307 if ($len > 0) {
870 $self->{filter_r} 1308 $self->{_activity} = AnyEvent->now;
871 ? $self->{filter_r}->($self, $rbuf) 1309
872 : $self->_drain_rbuf; 1310 if ($self->{tls}) {
1311 Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf);
1312
1313 &_dotls ($self);
1314 } else {
1315 $self->_drain_rbuf unless $self->{_in_drain};
1316 }
873 1317
874 } elsif (defined $len) { 1318 } elsif (defined $len) {
875 delete $self->{_rw}; 1319 delete $self->{_rw};
876 $self->{_eof} = 1; 1320 $self->{_eof} = 1;
877 $self->_drain_rbuf; 1321 $self->_drain_rbuf unless $self->{_in_drain};
878 1322
879 } elsif ($! != EAGAIN && $! != EINTR && $! != &AnyEvent::Util::WSAWOULDBLOCK) { 1323 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
880 return $self->error; 1324 return $self->_error ($!, 1);
881 } 1325 }
882 }); 1326 });
883 } 1327 }
884} 1328}
885 1329
1330# poll the write BIO and send the data if applicable
886sub _dotls { 1331sub _dotls {
887 my ($self) = @_; 1332 my ($self) = @_;
888 1333
1334 my $tmp;
1335
889 if (length $self->{_tls_wbuf}) { 1336 if (length $self->{_tls_wbuf}) {
890 while ((my $len = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) { 1337 while (($tmp = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) {
891 substr $self->{_tls_wbuf}, 0, $len, ""; 1338 substr $self->{_tls_wbuf}, 0, $tmp, "";
892 } 1339 }
893 } 1340 }
894 1341
1342 while (defined ($tmp = Net::SSLeay::read ($self->{tls}))) {
1343 unless (length $tmp) {
1344 # let's treat SSL-eof as we treat normal EOF
1345 delete $self->{_rw};
1346 $self->{_eof} = 1;
1347 &_freetls;
1348 }
1349
1350 $self->{tls_rbuf} .= $tmp;#d#
1351 $self->_drain_rbuf unless $self->{_in_drain};
1352 $self->{tls} or return; # tls session might have gone away in callback
1353 }
1354
1355 $tmp = Net::SSLeay::get_error ($self->{tls}, -1);
1356
1357 if ($tmp != Net::SSLeay::ERROR_WANT_READ ()) {
1358 if ($tmp == Net::SSLeay::ERROR_SYSCALL ()) {
1359 return $self->_error ($!, 1);
1360 } elsif ($tmp == Net::SSLeay::ERROR_SSL ()) {
1361 return $self->_error (&Errno::EIO, 1);
1362 }
1363
1364 # all other errors are fine for our purposes
1365 }
1366
895 if (defined (my $buf = Net::SSLeay::BIO_read ($self->{_wbio}))) { 1367 while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) {
896 $self->{wbuf} .= $buf; 1368 $self->{wbuf} .= $tmp;
897 $self->_drain_wbuf; 1369 $self->_drain_wbuf;
898 }
899
900 while (defined (my $buf = Net::SSLeay::read ($self->{tls}))) {
901 $self->{rbuf} .= $buf;
902 $self->_drain_rbuf;
903 }
904
905 my $err = Net::SSLeay::get_error ($self->{tls}, -1);
906
907 if ($err!= Net::SSLeay::ERROR_WANT_READ ()) {
908 if ($err == Net::SSLeay::ERROR_SYSCALL ()) {
909 $self->error;
910 } elsif ($err == Net::SSLeay::ERROR_SSL ()) {
911 $! = &Errno::EIO;
912 $self->error;
913 }
914
915 # all others are fine for our purposes
916 } 1370 }
917} 1371}
918 1372
919=item $handle->starttls ($tls[, $tls_ctx]) 1373=item $handle->starttls ($tls[, $tls_ctx])
920 1374
930 1384
931The TLS connection object will end up in C<< $handle->{tls} >> after this 1385The TLS connection object will end up in C<< $handle->{tls} >> after this
932call and can be used or changed to your liking. Note that the handshake 1386call and can be used or changed to your liking. Note that the handshake
933might have already started when this function returns. 1387might have already started when this function returns.
934 1388
935=cut 1389If it an error to start a TLS handshake more than once per
1390AnyEvent::Handle object (this is due to bugs in OpenSSL).
936 1391
937# TODO: maybe document... 1392=cut
1393
938sub starttls { 1394sub starttls {
939 my ($self, $ssl, $ctx) = @_; 1395 my ($self, $ssl, $ctx) = @_;
940 1396
941 $self->stoptls; 1397 require Net::SSLeay;
942 1398
1399 Carp::croak "it is an error to call starttls more than once on an AnyEvent::Handle object"
1400 if $self->{tls};
1401
943 if ($ssl eq "accept") { 1402 if ($ssl eq "accept") {
944 $ssl = Net::SSLeay::new ($ctx || TLS_CTX ()); 1403 $ssl = Net::SSLeay::new ($ctx || TLS_CTX ());
945 Net::SSLeay::set_accept_state ($ssl); 1404 Net::SSLeay::set_accept_state ($ssl);
946 } elsif ($ssl eq "connect") { 1405 } elsif ($ssl eq "connect") {
947 $ssl = Net::SSLeay::new ($ctx || TLS_CTX ()); 1406 $ssl = Net::SSLeay::new ($ctx || TLS_CTX ());
953 # basically, this is deep magic (because SSL_read should have the same issues) 1412 # basically, this is deep magic (because SSL_read should have the same issues)
954 # but the openssl maintainers basically said: "trust us, it just works". 1413 # but the openssl maintainers basically said: "trust us, it just works".
955 # (unfortunately, we have to hardcode constants because the abysmally misdesigned 1414 # (unfortunately, we have to hardcode constants because the abysmally misdesigned
956 # and mismaintained ssleay-module doesn't even offer them). 1415 # and mismaintained ssleay-module doesn't even offer them).
957 # http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html 1416 # http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html
1417 #
1418 # in short: this is a mess.
1419 #
1420 # note that we do not try to keep the length constant between writes as we are required to do.
1421 # we assume that most (but not all) of this insanity only applies to non-blocking cases,
1422 # and we drive openssl fully in blocking mode here. Or maybe we don't - openssl seems to
1423 # have identity issues in that area.
958 Net::SSLeay::CTX_set_mode ($self->{tls}, 1424 Net::SSLeay::CTX_set_mode ($self->{tls},
959 (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1) 1425 (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)
960 | (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2)); 1426 | (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2));
961 1427
962 $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); 1428 $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
963 $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); 1429 $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
964 1430
965 Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio}); 1431 Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio});
966 1432
967 $self->{filter_w} = sub { 1433 &_dotls; # need to trigger the initial handshake
968 $_[0]{_tls_wbuf} .= ${$_[1]}; 1434 $self->start_read; # make sure we actually do read
969 &_dotls;
970 };
971 $self->{filter_r} = sub {
972 Net::SSLeay::BIO_write ($_[0]{_rbio}, ${$_[1]});
973 &_dotls;
974 };
975} 1435}
976 1436
977=item $handle->stoptls 1437=item $handle->stoptls
978 1438
979Destroys the SSL connection, if any. Partial read or write data will be 1439Shuts down the SSL connection - this makes a proper EOF handshake by
980lost. 1440sending a close notify to the other side, but since OpenSSL doesn't
1441support non-blocking shut downs, it is not possible to re-use the stream
1442afterwards.
981 1443
982=cut 1444=cut
983 1445
984sub stoptls { 1446sub stoptls {
985 my ($self) = @_; 1447 my ($self) = @_;
986 1448
1449 if ($self->{tls}) {
1450 Net::SSLeay::shutdown ($self->{tls});
1451
1452 &_dotls;
1453
1454 # we don't give a shit. no, we do, but we can't. no...
1455 # we, we... have to use openssl :/
1456 &_freetls;
1457 }
1458}
1459
1460sub _freetls {
1461 my ($self) = @_;
1462
1463 return unless $self->{tls};
1464
987 Net::SSLeay::free (delete $self->{tls}) if $self->{tls}; 1465 Net::SSLeay::free (delete $self->{tls});
988 1466
989 delete $self->{_rbio}; 1467 delete @$self{qw(_rbio _wbio _tls_wbuf)};
990 delete $self->{_wbio};
991 delete $self->{_tls_wbuf};
992 delete $self->{filter_r};
993 delete $self->{filter_w};
994} 1468}
995 1469
996sub DESTROY { 1470sub DESTROY {
997 my $self = shift; 1471 my $self = shift;
998 1472
999 $self->stoptls; 1473 &_freetls;
1474
1475 my $linger = exists $self->{linger} ? $self->{linger} : 3600;
1476
1477 if ($linger && length $self->{wbuf}) {
1478 my $fh = delete $self->{fh};
1479 my $wbuf = delete $self->{wbuf};
1480
1481 my @linger;
1482
1483 push @linger, AnyEvent->io (fh => $fh, poll => "w", cb => sub {
1484 my $len = syswrite $fh, $wbuf, length $wbuf;
1485
1486 if ($len > 0) {
1487 substr $wbuf, 0, $len, "";
1488 } else {
1489 @linger = (); # end
1490 }
1491 });
1492 push @linger, AnyEvent->timer (after => $linger, cb => sub {
1493 @linger = ();
1494 });
1495 }
1496}
1497
1498=item $handle->destroy
1499
1500Shuts down the handle object as much as possible - this call ensures that
1501no further callbacks will be invoked and resources will be freed as much
1502as possible. You must not call any methods on the object afterwards.
1503
1504Normally, you can just "forget" any references to an AnyEvent::Handle
1505object and it will simply shut down. This works in fatal error and EOF
1506callbacks, as well as code outside. It does I<NOT> work in a read or write
1507callback, so when you want to destroy the AnyEvent::Handle object from
1508within such an callback. You I<MUST> call C<< ->destroy >> explicitly in
1509that case.
1510
1511The handle might still linger in the background and write out remaining
1512data, as specified by the C<linger> option, however.
1513
1514=cut
1515
1516sub destroy {
1517 my ($self) = @_;
1518
1519 $self->DESTROY;
1520 %$self = ();
1000} 1521}
1001 1522
1002=item AnyEvent::Handle::TLS_CTX 1523=item AnyEvent::Handle::TLS_CTX
1003 1524
1004This function creates and returns the Net::SSLeay::CTX object used by 1525This function creates and returns the Net::SSLeay::CTX object used by
1034 } 1555 }
1035} 1556}
1036 1557
1037=back 1558=back
1038 1559
1560
1561=head1 NONFREQUENTLY ASKED QUESTIONS
1562
1563=over 4
1564
1565=item I C<undef> the AnyEvent::Handle reference inside my callback and
1566still get further invocations!
1567
1568That's because AnyEvent::Handle keeps a reference to itself when handling
1569read or write callbacks.
1570
1571It is only safe to "forget" the reference inside EOF or error callbacks,
1572from within all other callbacks, you need to explicitly call the C<<
1573->destroy >> method.
1574
1575=item I get different callback invocations in TLS mode/Why can't I pause
1576reading?
1577
1578Unlike, say, TCP, TLS connections do not consist of two independent
1579communication channels, one for each direction. Or put differently. The
1580read and write directions are not independent of each other: you cannot
1581write data unless you are also prepared to read, and vice versa.
1582
1583This can mean than, in TLS mode, you might get C<on_error> or C<on_eof>
1584callback invocations when you are not expecting any read data - the reason
1585is that AnyEvent::Handle always reads in TLS mode.
1586
1587During the connection, you have to make sure that you always have a
1588non-empty read-queue, or an C<on_read> watcher. At the end of the
1589connection (or when you no longer want to use it) you can call the
1590C<destroy> method.
1591
1592=item How do I read data until the other side closes the connection?
1593
1594If you just want to read your data into a perl scalar, the easiest way
1595to achieve this is by setting an C<on_read> callback that does nothing,
1596clearing the C<on_eof> callback and in the C<on_error> callback, the data
1597will be in C<$_[0]{rbuf}>:
1598
1599 $handle->on_read (sub { });
1600 $handle->on_eof (undef);
1601 $handle->on_error (sub {
1602 my $data = delete $_[0]{rbuf};
1603 undef $handle;
1604 });
1605
1606The reason to use C<on_error> is that TCP connections, due to latencies
1607and packets loss, might get closed quite violently with an error, when in
1608fact, all data has been received.
1609
1610It is usually better to use acknowledgements when transferring data,
1611to make sure the other side hasn't just died and you got the data
1612intact. This is also one reason why so many internet protocols have an
1613explicit QUIT command.
1614
1615=item I don't want to destroy the handle too early - how do I wait until
1616all data has been written?
1617
1618After writing your last bits of data, set the C<on_drain> callback
1619and destroy the handle in there - with the default setting of
1620C<low_water_mark> this will be called precisely when all data has been
1621written to the socket:
1622
1623 $handle->push_write (...);
1624 $handle->on_drain (sub {
1625 warn "all data submitted to the kernel\n";
1626 undef $handle;
1627 });
1628
1629=back
1630
1631
1039=head1 SUBCLASSING AnyEvent::Handle 1632=head1 SUBCLASSING AnyEvent::Handle
1040 1633
1041In many cases, you might want to subclass AnyEvent::Handle. 1634In many cases, you might want to subclass AnyEvent::Handle.
1042 1635
1043To make this easier, a given version of AnyEvent::Handle uses these 1636To make this easier, a given version of AnyEvent::Handle uses these
1046=over 4 1639=over 4
1047 1640
1048=item * all constructor arguments become object members. 1641=item * all constructor arguments become object members.
1049 1642
1050At least initially, when you pass a C<tls>-argument to the constructor it 1643At least initially, when you pass a C<tls>-argument to the constructor it
1051will end up in C<< $handle->{tls} >>. Those members might be changes or 1644will end up in C<< $handle->{tls} >>. Those members might be changed or
1052mutated later on (for example C<tls> will hold the TLS connection object). 1645mutated later on (for example C<tls> will hold the TLS connection object).
1053 1646
1054=item * other object member names are prefixed with an C<_>. 1647=item * other object member names are prefixed with an C<_>.
1055 1648
1056All object members not explicitly documented (internal use) are prefixed 1649All object members not explicitly documented (internal use) are prefixed

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