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Comparing AnyEvent/lib/AnyEvent/Handle.pm (file contents):
Revision 1.80 by root, Sun Jul 27 08:43:32 2008 UTC vs.
Revision 1.112 by root, Wed Jan 21 06:01:35 2009 UTC

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 = 4.22; 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 => $cb->($handle) 82=item on_eof => $cb->($handle)
79 83
80Set the callback to be called when an end-of-file condition is detected, 84Set the callback to be called when an end-of-file condition is detected,
81i.e. in the case of a socket, when the other side has closed the 85i.e. in the case of a socket, when the other side has closed the
82connection cleanly. 86connection cleanly.
83 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
84While not mandatory, it is I<highly> recommended to set an eof callback, 93While not mandatory, it is I<highly> recommended to set an EOF callback,
85otherwise 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
86waiting for data. 95waiting for data.
87 96
88If an EOF condition has been detected but no C<on_eof> callback has been 97If an EOF condition has been detected but no C<on_eof> callback has been
89set, then a fatal error will be raised with C<$!> set to <0>. 98set, then a fatal error will be raised with C<$!> set to <0>.
93This is the error callback, which is called when, well, some error 102This is the error callback, which is called when, well, some error
94occured, such as not being able to resolve the hostname, failure to 103occured, such as not being able to resolve the hostname, failure to
95connect or a read error. 104connect or a read error.
96 105
97Some errors are fatal (which is indicated by C<$fatal> being true). On 106Some errors are fatal (which is indicated by C<$fatal> being true). On
98fatal errors the handle object will be shut down and will not be 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
99usable. Non-fatal errors can be retried by simply returning, but it is 112Non-fatal errors can be retried by simply returning, but it is recommended
100recommended to simply ignore this parameter and instead abondon the handle 113to simply ignore this parameter and instead abondon the handle object
101object when this callback is invoked. 114when this callback is invoked. Examples of non-fatal errors are timeouts
115C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>).
102 116
103On callback entrance, the value of C<$!> contains the operating system 117On callback entrance, the value of C<$!> contains the operating system
104error (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT> or C<EBADMSG>). 118error (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT> or C<EBADMSG>).
105 119
106While 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
138=item timeout => $fractional_seconds 152=item timeout => $fractional_seconds
139 153
140If non-zero, then this enables an "inactivity" timeout: whenever this many 154If non-zero, then this enables an "inactivity" timeout: whenever this many
141seconds pass without a successful read or write on the underlying file 155seconds pass without a successful read or write on the underlying file
142handle, the C<on_timeout> callback will be invoked (and if that one is 156handle, the C<on_timeout> callback will be invoked (and if that one is
143missing, an C<ETIMEDOUT> error will be raised). 157missing, a non-fatal C<ETIMEDOUT> error will be raised).
144 158
145Note that timeout processing is also active when you currently do not have 159Note that timeout processing is also active when you currently do not have
146any outstanding read or write requests: If you plan to keep the connection 160any outstanding read or write requests: If you plan to keep the connection
147idle then you should disable the timout temporarily or ignore the timeout 161idle then you should disable the timout temporarily or ignore the timeout
148in the C<on_timeout> callback. 162in the C<on_timeout> callback, in which case AnyEvent::Handle will simply
163restart the timeout.
149 164
150Zero (the default) disables this timeout. 165Zero (the default) disables this timeout.
151 166
152=item on_timeout => $cb->($handle) 167=item on_timeout => $cb->($handle)
153 168
157 172
158=item rbuf_max => <bytes> 173=item rbuf_max => <bytes>
159 174
160If 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>)
161when 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
162avoid denial-of-service attacks. 177avoid some forms of denial-of-service attacks.
163 178
164For example, a server accepting connections from untrusted sources should 179For example, a server accepting connections from untrusted sources should
165be 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
166(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
167amount 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
168isn't finished). 183isn't finished).
169 184
170=item autocork => <boolean> 185=item autocork => <boolean>
171 186
172When disabled (the default), then C<push_write> will try to immediately 187When disabled (the default), then C<push_write> will try to immediately
173write the data to the handle if possible. This avoids having to register 188write the data to the handle, if possible. This avoids having to register
174a write watcher and wait for the next event loop iteration, but can be 189a write watcher and wait for the next event loop iteration, but can
175inefficient if you write multiple small chunks (this disadvantage is 190be inefficient if you write multiple small chunks (on the wire, this
176usually avoided by your kernel's nagle algorithm, see C<low_delay>). 191disadvantage is usually avoided by your kernel's nagle algorithm, see
192C<no_delay>, but this option can save costly syscalls).
177 193
178When enabled, then writes will always be queued till the next event loop 194When enabled, then writes will always be queued till the next event loop
179iteration. This is efficient when you do many small writes per iteration, 195iteration. This is efficient when you do many small writes per iteration,
180but less efficient when you do a single write only. 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.
181 198
182=item no_delay => <boolean> 199=item no_delay => <boolean>
183 200
184When doing small writes on sockets, your operating system kernel might 201When doing small writes on sockets, your operating system kernel might
185wait a bit for more data before actually sending it out. This is called 202wait a bit for more data before actually sending it out. This is called
186the Nagle algorithm, and usually it is beneficial. 203the Nagle algorithm, and usually it is beneficial.
187 204
188In some situations you want as low a delay as possible, which cna be 205In some situations you want as low a delay as possible, which can be
189accomplishd by setting this option to true. 206accomplishd by setting this option to a true value.
190 207
191The default is your opertaing system's default behaviour, this option 208The default is your opertaing system's default behaviour (most likely
192explicitly enables or disables it, if possible. 209enabled), this option explicitly enables or disables it, if possible.
193 210
194=item read_size => <bytes> 211=item read_size => <bytes>
195 212
196The 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
197during each (loop iteration). Default: C<8192>. 214try to read during each loop iteration, which affects memory
215requirements). Default: C<8192>.
198 216
199=item low_water_mark => <bytes> 217=item low_water_mark => <bytes>
200 218
201Sets 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
202buffer: 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
203considered empty. 221considered empty.
204 222
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
205=item linger => <seconds> 228=item linger => <seconds>
206 229
207If non-zero (default: C<3600>), then the destructor of the 230If non-zero (default: C<3600>), then the destructor of the
208AnyEvent::Handle object will check wether there is still outstanding write 231AnyEvent::Handle object will check whether there is still outstanding
209data and will install a watcher that will write out this data. No errors 232write data and will install a watcher that will write this data to the
210will be reported (this mostly matches how the operating system treats 233socket. No errors will be reported (this mostly matches how the operating
211outstanding data at socket close time). 234system treats outstanding data at socket close time).
212 235
213This will not work for partial TLS data that could not yet been 236This will not work for partial TLS data that could not be encoded
214encoded. This data will be lost. 237yet. This data will be lost. Calling the C<stoptls> method in time might
238help.
215 239
216=item tls => "accept" | "connect" | Net::SSLeay::SSL object 240=item tls => "accept" | "connect" | Net::SSLeay::SSL object
217 241
218When this parameter is given, it enables TLS (SSL) mode, that means it 242When this parameter is given, it enables TLS (SSL) mode, that means
219will start making tls handshake and will transparently encrypt/decrypt 243AnyEvent will start a TLS handshake as soon as the conenction has been
220data. 244established and will transparently encrypt/decrypt data afterwards.
221 245
222TLS mode requires Net::SSLeay to be installed (it will be loaded 246TLS mode requires Net::SSLeay to be installed (it will be loaded
223automatically 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.
224 250
225For 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
226connection, use C<connect> mode. 252C<accept>, and for the TLS client side of a connection, use C<connect>
253mode.
227 254
228You can also provide your own TLS connection object, but you have 255You can also provide your own TLS connection object, but you have
229to 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>
230or 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
231AnyEvent::Handle. 258AnyEvent::Handle.
232 259
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
233See 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.
234 266
235=item tls_ctx => $ssl_ctx 267=item tls_ctx => $ssl_ctx
236 268
237Use 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
238(unless a connection object was specified directly). If this parameter is 270(unless a connection object was specified directly). If this parameter is
239missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>. 271missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>.
240 272
241=item json => JSON or JSON::XS object 273=item json => JSON or JSON::XS object
242 274
243This is the json coder object used by the C<json> read and write types. 275This is the json coder object used by the C<json> read and write types.
244 276
245If you don't supply it, then AnyEvent::Handle will create and use a 277If you don't supply it, then AnyEvent::Handle will create and use a
246suitable one, which will write and expect UTF-8 encoded JSON texts. 278suitable one (on demand), which will write and expect UTF-8 encoded JSON
279texts.
247 280
248Note that you are responsible to depend on the JSON module if you want to 281Note that you are responsible to depend on the JSON module if you want to
249use this functionality, as AnyEvent does not have a dependency itself. 282use this functionality, as AnyEvent does not have a dependency itself.
250 283
251=item filter_r => $cb
252
253=item filter_w => $cb
254
255These exist, but are undocumented at this time.
256
257=back 284=back
258 285
259=cut 286=cut
260 287
261sub new { 288sub new {
265 292
266 $self->{fh} or Carp::croak "mandatory argument fh is missing"; 293 $self->{fh} or Carp::croak "mandatory argument fh is missing";
267 294
268 AnyEvent::Util::fh_nonblocking $self->{fh}, 1; 295 AnyEvent::Util::fh_nonblocking $self->{fh}, 1;
269 296
270 if ($self->{tls}) {
271 require Net::SSLeay;
272 $self->starttls (delete $self->{tls}, delete $self->{tls_ctx}); 297 $self->starttls (delete $self->{tls}, delete $self->{tls_ctx})
273 } 298 if $self->{tls};
274 299
275 $self->{_activity} = AnyEvent->now; 300 $self->{_activity} = AnyEvent->now;
276 $self->_timeout; 301 $self->_timeout;
277 302
278 $self->on_drain (delete $self->{on_drain}) if exists $self->{on_drain}; 303 $self->on_drain (delete $self->{on_drain}) if exists $self->{on_drain};
290 delete $self->{_tw}; 315 delete $self->{_tw};
291 delete $self->{_rw}; 316 delete $self->{_rw};
292 delete $self->{_ww}; 317 delete $self->{_ww};
293 delete $self->{fh}; 318 delete $self->{fh};
294 319
295 $self->stoptls; 320 &_freetls;
321
322 delete $self->{on_read};
323 delete $self->{_queue};
296} 324}
297 325
298sub _error { 326sub _error {
299 my ($self, $errno, $fatal) = @_; 327 my ($self, $errno, $fatal) = @_;
300 328
303 331
304 $! = $errno; 332 $! = $errno;
305 333
306 if ($self->{on_error}) { 334 if ($self->{on_error}) {
307 $self->{on_error}($self, $fatal); 335 $self->{on_error}($self, $fatal);
308 } else { 336 } elsif ($self->{fh}) {
309 Carp::croak "AnyEvent::Handle uncaught error: $!"; 337 Carp::croak "AnyEvent::Handle uncaught error: $!";
310 } 338 }
311} 339}
312 340
313=item $fh = $handle->fh 341=item $fh = $handle->fh
314 342
315This 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.
316 344
317=cut 345=cut
318 346
319sub fh { $_[0]{fh} } 347sub fh { $_[0]{fh} }
320 348
338 $_[0]{on_eof} = $_[1]; 366 $_[0]{on_eof} = $_[1];
339} 367}
340 368
341=item $handle->on_timeout ($cb) 369=item $handle->on_timeout ($cb)
342 370
343Replace the current C<on_timeout> callback, or disables the callback 371Replace the current C<on_timeout> callback, or disables the callback (but
344(but not the timeout) if C<$cb> = C<undef>. See C<timeout> constructor 372not the timeout) if C<$cb> = C<undef>. See the C<timeout> constructor
345argument. 373argument and method.
346 374
347=cut 375=cut
348 376
349sub on_timeout { 377sub on_timeout {
350 $_[0]{on_timeout} = $_[1]; 378 $_[0]{on_timeout} = $_[1];
351} 379}
352 380
353=item $handle->autocork ($boolean) 381=item $handle->autocork ($boolean)
354 382
355Enables or disables the current autocork behaviour (see C<autocork> 383Enables or disables the current autocork behaviour (see C<autocork>
356constructor argument). 384constructor argument). Changes will only take effect on the next write.
357 385
358=cut 386=cut
387
388sub autocork {
389 $_[0]{autocork} = $_[1];
390}
359 391
360=item $handle->no_delay ($boolean) 392=item $handle->no_delay ($boolean)
361 393
362Enables or disables the C<no_delay> setting (see constructor argument of 394Enables or disables the C<no_delay> setting (see constructor argument of
363the same name for details). 395the same name for details).
456 my ($self, $cb) = @_; 488 my ($self, $cb) = @_;
457 489
458 $self->{on_drain} = $cb; 490 $self->{on_drain} = $cb;
459 491
460 $cb->($self) 492 $cb->($self)
461 if $cb && $self->{low_water_mark} >= length $self->{wbuf}; 493 if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf});
462} 494}
463 495
464=item $handle->push_write ($data) 496=item $handle->push_write ($data)
465 497
466Queues 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
483 substr $self->{wbuf}, 0, $len, ""; 515 substr $self->{wbuf}, 0, $len, "";
484 516
485 $self->{_activity} = AnyEvent->now; 517 $self->{_activity} = AnyEvent->now;
486 518
487 $self->{on_drain}($self) 519 $self->{on_drain}($self)
488 if $self->{low_water_mark} >= length $self->{wbuf} 520 if $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf})
489 && $self->{on_drain}; 521 && $self->{on_drain};
490 522
491 delete $self->{_ww} unless length $self->{wbuf}; 523 delete $self->{_ww} unless length $self->{wbuf};
492 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) { 524 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
493 $self->_error ($!, 1); 525 $self->_error ($!, 1);
517 549
518 @_ = ($WH{$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")
519 ->($self, @_); 551 ->($self, @_);
520 } 552 }
521 553
522 if ($self->{filter_w}) { 554 if ($self->{tls}) {
523 $self->{filter_w}($self, \$_[0]); 555 $self->{_tls_wbuf} .= $_[0];
556
557 &_dotls ($self);
524 } else { 558 } else {
525 $self->{wbuf} .= $_[0]; 559 $self->{wbuf} .= $_[0];
526 $self->_drain_wbuf; 560 $self->_drain_wbuf;
527 } 561 }
528} 562}
545=cut 579=cut
546 580
547register_write_type netstring => sub { 581register_write_type netstring => sub {
548 my ($self, $string) = @_; 582 my ($self, $string) = @_;
549 583
550 sprintf "%d:%s,", (length $string), $string 584 (length $string) . ":$string,"
551}; 585};
552 586
553=item packstring => $format, $data 587=item packstring => $format, $data
554 588
555An octet string prefixed with an encoded length. The encoding C<$format> 589An octet string prefixed with an encoded length. The encoding C<$format>
729 763
730 if ( 764 if (
731 defined $self->{rbuf_max} 765 defined $self->{rbuf_max}
732 && $self->{rbuf_max} < length $self->{rbuf} 766 && $self->{rbuf_max} < length $self->{rbuf}
733 ) { 767 ) {
734 return $self->_error (&Errno::ENOSPC, 1); 768 $self->_error (&Errno::ENOSPC, 1), return;
735 } 769 }
736 770
737 while () { 771 while () {
738 my $len = length $self->{rbuf}; 772 my $len = length $self->{rbuf};
739 773
740 if (my $cb = shift @{ $self->{_queue} }) { 774 if (my $cb = shift @{ $self->{_queue} }) {
741 unless ($cb->($self)) { 775 unless ($cb->($self)) {
742 if ($self->{_eof}) { 776 if ($self->{_eof}) {
743 # 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)
744 $self->_error (&Errno::EPIPE, 1), last; 778 $self->_error (&Errno::EPIPE, 1), return;
745 } 779 }
746 780
747 unshift @{ $self->{_queue} }, $cb; 781 unshift @{ $self->{_queue} }, $cb;
748 last; 782 last;
749 } 783 }
757 && !@{ $self->{_queue} } # and the queue is still empty 791 && !@{ $self->{_queue} } # and the queue is still empty
758 && $self->{on_read} # but we still have on_read 792 && $self->{on_read} # but we still have on_read
759 ) { 793 ) {
760 # no further data will arrive 794 # no further data will arrive
761 # so no progress can be made 795 # so no progress can be made
762 $self->_error (&Errno::EPIPE, 1), last 796 $self->_error (&Errno::EPIPE, 1), return
763 if $self->{_eof}; 797 if $self->{_eof};
764 798
765 last; # more data might arrive 799 last; # more data might arrive
766 } 800 }
767 } else { 801 } else {
768 # read side becomes idle 802 # read side becomes idle
769 delete $self->{_rw}; 803 delete $self->{_rw} unless $self->{tls};
770 last; 804 last;
771 } 805 }
772 } 806 }
773 807
774 if ($self->{_eof}) { 808 if ($self->{_eof}) {
1069An octet string prefixed with an encoded length. The encoding C<$format> 1103An octet string prefixed with an encoded length. The encoding C<$format>
1070uses the same format as a Perl C<pack> format, but must specify a single 1104uses the same format as a Perl C<pack> format, but must specify a single
1071integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an 1105integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
1072optional C<!>, C<< < >> or C<< > >> modifier). 1106optional C<!>, C<< < >> or C<< > >> modifier).
1073 1107
1074DNS over TCP uses a prefix of C<n>, EPP uses a prefix of C<N>. 1108For example, DNS over TCP uses a prefix of C<n> (2 octet network order),
1109EPP uses a prefix of C<N> (4 octtes).
1075 1110
1076Example: read a block of data prefixed by its length in BER-encoded 1111Example: read a block of data prefixed by its length in BER-encoded
1077format (very efficient). 1112format (very efficient).
1078 1113
1079 $handle->push_read (packstring => "w", sub { 1114 $handle->push_read (packstring => "w", sub {
1109 } 1144 }
1110}; 1145};
1111 1146
1112=item json => $cb->($handle, $hash_or_arrayref) 1147=item json => $cb->($handle, $hash_or_arrayref)
1113 1148
1114Reads a JSON object or array, decodes it and passes it to the callback. 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.
1115 1151
1116If a C<json> object was passed to the constructor, then that will be used 1152If a C<json> object was passed to the constructor, then that will be used
1117for the final decode, otherwise it will create a JSON coder expecting UTF-8. 1153for the final decode, otherwise it will create a JSON coder expecting UTF-8.
1118 1154
1119This read type uses the incremental parser available with JSON version 1155This read type uses the incremental parser available with JSON version
1136 my $rbuf = \$self->{rbuf}; 1172 my $rbuf = \$self->{rbuf};
1137 1173
1138 my $json = $self->{json} ||= JSON->new->utf8; 1174 my $json = $self->{json} ||= JSON->new->utf8;
1139 1175
1140 sub { 1176 sub {
1177 eval {
1141 my $ref = $json->incr_parse ($self->{rbuf}); 1178 my $ref = $json->incr_parse ($self->{rbuf});
1142 1179
1143 if ($ref) { 1180 if ($ref) {
1181 $self->{rbuf} = $json->incr_text;
1182 $json->incr_text = "";
1183 $cb->($self, $ref);
1184
1185 1
1186 } else {
1187 $self->{rbuf} = "";
1188 ()
1189 }
1190
1191 1
1192 } or do {
1193 # error case
1194 $json->incr_skip;
1195
1144 $self->{rbuf} = $json->incr_text; 1196 $self->{rbuf} = $json->incr_text;
1145 $json->incr_text = ""; 1197 $json->incr_text = "";
1146 $cb->($self, $ref);
1147 1198
1148 1 1199 $self->_error (&Errno::EBADMSG);
1149 } else {
1150 $self->{rbuf} = "";
1151 ()
1152 } 1200 };
1153 } 1201 }
1154}; 1202};
1155 1203
1156=item storable => $cb->($handle, $ref) 1204=item storable => $cb->($handle, $ref)
1157 1205
1232Note that AnyEvent::Handle will automatically C<start_read> for you when 1280Note that AnyEvent::Handle will automatically C<start_read> for you when
1233you change the C<on_read> callback or push/unshift a read callback, and it 1281you change the C<on_read> callback or push/unshift a read callback, and it
1234will automatically C<stop_read> for you when neither C<on_read> is set nor 1282will automatically C<stop_read> for you when neither C<on_read> is set nor
1235there are any read requests in the queue. 1283there are any read requests in the queue.
1236 1284
1285These methods will have no effect when in TLS mode (as TLS doesn't support
1286half-duplex connections).
1287
1237=cut 1288=cut
1238 1289
1239sub stop_read { 1290sub stop_read {
1240 my ($self) = @_; 1291 my ($self) = @_;
1241 1292
1242 delete $self->{_rw}; 1293 delete $self->{_rw} unless $self->{tls};
1243} 1294}
1244 1295
1245sub start_read { 1296sub start_read {
1246 my ($self) = @_; 1297 my ($self) = @_;
1247 1298
1248 unless ($self->{_rw} || $self->{_eof}) { 1299 unless ($self->{_rw} || $self->{_eof}) {
1249 Scalar::Util::weaken $self; 1300 Scalar::Util::weaken $self;
1250 1301
1251 $self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub { 1302 $self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub {
1252 my $rbuf = $self->{filter_r} ? \my $buf : \$self->{rbuf}; 1303 my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf});
1253 my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf; 1304 my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf;
1254 1305
1255 if ($len > 0) { 1306 if ($len > 0) {
1256 $self->{_activity} = AnyEvent->now; 1307 $self->{_activity} = AnyEvent->now;
1257 1308
1258 $self->{filter_r} 1309 if ($self->{tls}) {
1259 ? $self->{filter_r}($self, $rbuf) 1310 Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf);
1260 : $self->{_in_drain} || $self->_drain_rbuf; 1311
1312 &_dotls ($self);
1313 } else {
1314 $self->_drain_rbuf unless $self->{_in_drain};
1315 }
1261 1316
1262 } elsif (defined $len) { 1317 } elsif (defined $len) {
1263 delete $self->{_rw}; 1318 delete $self->{_rw};
1264 $self->{_eof} = 1; 1319 $self->{_eof} = 1;
1265 $self->_drain_rbuf unless $self->{_in_drain}; 1320 $self->_drain_rbuf unless $self->{_in_drain};
1269 } 1324 }
1270 }); 1325 });
1271 } 1326 }
1272} 1327}
1273 1328
1329# poll the write BIO and send the data if applicable
1274sub _dotls { 1330sub _dotls {
1275 my ($self) = @_; 1331 my ($self) = @_;
1276 1332
1277 my $buf; 1333 my $tmp;
1278 1334
1279 if (length $self->{_tls_wbuf}) { 1335 if (length $self->{_tls_wbuf}) {
1280 while ((my $len = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) { 1336 while (($tmp = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) {
1281 substr $self->{_tls_wbuf}, 0, $len, ""; 1337 substr $self->{_tls_wbuf}, 0, $tmp, "";
1282 } 1338 }
1283 } 1339 }
1284 1340
1285 if (length ($buf = Net::SSLeay::BIO_read ($self->{_wbio}))) {
1286 $self->{wbuf} .= $buf;
1287 $self->_drain_wbuf;
1288 }
1289
1290 while (defined ($buf = Net::SSLeay::read ($self->{tls}))) { 1341 while (defined ($tmp = Net::SSLeay::read ($self->{tls}))) {
1291 if (length $buf) { 1342 unless (length $tmp) {
1292 $self->{rbuf} .= $buf;
1293 $self->_drain_rbuf unless $self->{_in_drain};
1294 } else {
1295 # let's treat SSL-eof as we treat normal EOF 1343 # let's treat SSL-eof as we treat normal EOF
1344 delete $self->{_rw};
1296 $self->{_eof} = 1; 1345 $self->{_eof} = 1;
1297 $self->_shutdown; 1346 &_freetls;
1298 return;
1299 } 1347 }
1300 }
1301 1348
1349 $self->{rbuf} .= $tmp;
1350 $self->_drain_rbuf unless $self->{_in_drain};
1351 $self->{tls} or return; # tls session might have gone away in callback
1352 }
1353
1302 my $err = Net::SSLeay::get_error ($self->{tls}, -1); 1354 $tmp = Net::SSLeay::get_error ($self->{tls}, -1);
1303 1355
1304 if ($err!= Net::SSLeay::ERROR_WANT_READ ()) { 1356 if ($tmp != Net::SSLeay::ERROR_WANT_READ ()) {
1305 if ($err == Net::SSLeay::ERROR_SYSCALL ()) { 1357 if ($tmp == Net::SSLeay::ERROR_SYSCALL ()) {
1306 return $self->_error ($!, 1); 1358 return $self->_error ($!, 1);
1307 } elsif ($err == Net::SSLeay::ERROR_SSL ()) { 1359 } elsif ($tmp == Net::SSLeay::ERROR_SSL ()) {
1308 return $self->_error (&Errno::EIO, 1); 1360 return $self->_error (&Errno::EIO, 1);
1309 } 1361 }
1310 1362
1311 # all others are fine for our purposes 1363 # all other errors are fine for our purposes
1364 }
1365
1366 while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) {
1367 $self->{wbuf} .= $tmp;
1368 $self->_drain_wbuf;
1312 } 1369 }
1313} 1370}
1314 1371
1315=item $handle->starttls ($tls[, $tls_ctx]) 1372=item $handle->starttls ($tls[, $tls_ctx])
1316 1373
1326 1383
1327The TLS connection object will end up in C<< $handle->{tls} >> after this 1384The TLS connection object will end up in C<< $handle->{tls} >> after this
1328call and can be used or changed to your liking. Note that the handshake 1385call and can be used or changed to your liking. Note that the handshake
1329might have already started when this function returns. 1386might have already started when this function returns.
1330 1387
1388If it an error to start a TLS handshake more than once per
1389AnyEvent::Handle object (this is due to bugs in OpenSSL).
1390
1331=cut 1391=cut
1332 1392
1333sub starttls { 1393sub starttls {
1334 my ($self, $ssl, $ctx) = @_; 1394 my ($self, $ssl, $ctx) = @_;
1335 1395
1336 $self->stoptls; 1396 require Net::SSLeay;
1337 1397
1398 Carp::croak "it is an error to call starttls more than once on an AnyEvent::Handle object"
1399 if $self->{tls};
1400
1338 if ($ssl eq "accept") { 1401 if ($ssl eq "accept") {
1339 $ssl = Net::SSLeay::new ($ctx || TLS_CTX ()); 1402 $ssl = Net::SSLeay::new ($ctx || TLS_CTX ());
1340 Net::SSLeay::set_accept_state ($ssl); 1403 Net::SSLeay::set_accept_state ($ssl);
1341 } elsif ($ssl eq "connect") { 1404 } elsif ($ssl eq "connect") {
1342 $ssl = Net::SSLeay::new ($ctx || TLS_CTX ()); 1405 $ssl = Net::SSLeay::new ($ctx || TLS_CTX ());
1348 # basically, this is deep magic (because SSL_read should have the same issues) 1411 # basically, this is deep magic (because SSL_read should have the same issues)
1349 # but the openssl maintainers basically said: "trust us, it just works". 1412 # but the openssl maintainers basically said: "trust us, it just works".
1350 # (unfortunately, we have to hardcode constants because the abysmally misdesigned 1413 # (unfortunately, we have to hardcode constants because the abysmally misdesigned
1351 # and mismaintained ssleay-module doesn't even offer them). 1414 # and mismaintained ssleay-module doesn't even offer them).
1352 # http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html 1415 # http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html
1416 #
1417 # in short: this is a mess.
1418 #
1419 # note that we do not try to keep the length constant between writes as we are required to do.
1420 # we assume that most (but not all) of this insanity only applies to non-blocking cases,
1421 # and we drive openssl fully in blocking mode here. Or maybe we don't - openssl seems to
1422 # have identity issues in that area.
1353 Net::SSLeay::CTX_set_mode ($self->{tls}, 1423 Net::SSLeay::CTX_set_mode ($self->{tls},
1354 (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1) 1424 (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)
1355 | (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2)); 1425 | (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2));
1356 1426
1357 $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); 1427 $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1358 $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); 1428 $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1359 1429
1360 Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio}); 1430 Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio});
1361 1431
1362 $self->{filter_w} = sub { 1432 &_dotls; # need to trigger the initial handshake
1363 $_[0]{_tls_wbuf} .= ${$_[1]}; 1433 $self->start_read; # make sure we actually do read
1364 &_dotls;
1365 };
1366 $self->{filter_r} = sub {
1367 Net::SSLeay::BIO_write ($_[0]{_rbio}, ${$_[1]});
1368 &_dotls;
1369 };
1370} 1434}
1371 1435
1372=item $handle->stoptls 1436=item $handle->stoptls
1373 1437
1374Destroys the SSL connection, if any. Partial read or write data will be 1438Shuts down the SSL connection - this makes a proper EOF handshake by
1375lost. 1439sending a close notify to the other side, but since OpenSSL doesn't
1440support non-blocking shut downs, it is not possible to re-use the stream
1441afterwards.
1376 1442
1377=cut 1443=cut
1378 1444
1379sub stoptls { 1445sub stoptls {
1380 my ($self) = @_; 1446 my ($self) = @_;
1381 1447
1448 if ($self->{tls}) {
1449 Net::SSLeay::shutdown ($self->{tls});
1450
1451 &_dotls;
1452
1453 # we don't give a shit. no, we do, but we can't. no...
1454 # we, we... have to use openssl :/
1455 &_freetls;
1456 }
1457}
1458
1459sub _freetls {
1460 my ($self) = @_;
1461
1462 return unless $self->{tls};
1463
1382 Net::SSLeay::free (delete $self->{tls}) if $self->{tls}; 1464 Net::SSLeay::free (delete $self->{tls});
1383 1465
1384 delete $self->{_rbio}; 1466 delete @$self{qw(_rbio _wbio _tls_wbuf)};
1385 delete $self->{_wbio};
1386 delete $self->{_tls_wbuf};
1387 delete $self->{filter_r};
1388 delete $self->{filter_w};
1389} 1467}
1390 1468
1391sub DESTROY { 1469sub DESTROY {
1392 my $self = shift; 1470 my $self = shift;
1393 1471
1394 $self->stoptls; 1472 &_freetls;
1395 1473
1396 my $linger = exists $self->{linger} ? $self->{linger} : 3600; 1474 my $linger = exists $self->{linger} ? $self->{linger} : 3600;
1397 1475
1398 if ($linger && length $self->{wbuf}) { 1476 if ($linger && length $self->{wbuf}) {
1399 my $fh = delete $self->{fh}; 1477 my $fh = delete $self->{fh};
1414 @linger = (); 1492 @linger = ();
1415 }); 1493 });
1416 } 1494 }
1417} 1495}
1418 1496
1497=item $handle->destroy
1498
1499Shuts down the handle object as much as possible - this call ensures that
1500no further callbacks will be invoked and resources will be freed as much
1501as possible. You must not call any methods on the object afterwards.
1502
1503Normally, you can just "forget" any references to an AnyEvent::Handle
1504object and it will simply shut down. This works in fatal error and EOF
1505callbacks, as well as code outside. It does I<NOT> work in a read or write
1506callback, so when you want to destroy the AnyEvent::Handle object from
1507within such an callback. You I<MUST> call C<< ->destroy >> explicitly in
1508that case.
1509
1510The handle might still linger in the background and write out remaining
1511data, as specified by the C<linger> option, however.
1512
1513=cut
1514
1515sub destroy {
1516 my ($self) = @_;
1517
1518 $self->DESTROY;
1519 %$self = ();
1520}
1521
1419=item AnyEvent::Handle::TLS_CTX 1522=item AnyEvent::Handle::TLS_CTX
1420 1523
1421This function creates and returns the Net::SSLeay::CTX object used by 1524This function creates and returns the Net::SSLeay::CTX object used by
1422default for TLS mode. 1525default for TLS mode.
1423 1526
1451 } 1554 }
1452} 1555}
1453 1556
1454=back 1557=back
1455 1558
1559
1560=head1 NONFREQUENTLY ASKED QUESTIONS
1561
1562=over 4
1563
1564=item I C<undef> the AnyEvent::Handle reference inside my callback and
1565still get further invocations!
1566
1567That's because AnyEvent::Handle keeps a reference to itself when handling
1568read or write callbacks.
1569
1570It is only safe to "forget" the reference inside EOF or error callbacks,
1571from within all other callbacks, you need to explicitly call the C<<
1572->destroy >> method.
1573
1574=item I get different callback invocations in TLS mode/Why can't I pause
1575reading?
1576
1577Unlike, say, TCP, TLS connections do not consist of two independent
1578communication channels, one for each direction. Or put differently. The
1579read and write directions are not independent of each other: you cannot
1580write data unless you are also prepared to read, and vice versa.
1581
1582This can mean than, in TLS mode, you might get C<on_error> or C<on_eof>
1583callback invocations when you are not expecting any read data - the reason
1584is that AnyEvent::Handle always reads in TLS mode.
1585
1586During the connection, you have to make sure that you always have a
1587non-empty read-queue, or an C<on_read> watcher. At the end of the
1588connection (or when you no longer want to use it) you can call the
1589C<destroy> method.
1590
1591=item How do I read data until the other side closes the connection?
1592
1593If you just want to read your data into a perl scalar, the easiest way
1594to achieve this is by setting an C<on_read> callback that does nothing,
1595clearing the C<on_eof> callback and in the C<on_error> callback, the data
1596will be in C<$_[0]{rbuf}>:
1597
1598 $handle->on_read (sub { });
1599 $handle->on_eof (undef);
1600 $handle->on_error (sub {
1601 my $data = delete $_[0]{rbuf};
1602 undef $handle;
1603 });
1604
1605The reason to use C<on_error> is that TCP connections, due to latencies
1606and packets loss, might get closed quite violently with an error, when in
1607fact, all data has been received.
1608
1609It is usually better to use acknowledgements when transferring data,
1610to make sure the other side hasn't just died and you got the data
1611intact. This is also one reason why so many internet protocols have an
1612explicit QUIT command.
1613
1614=item I don't want to destroy the handle too early - how do I wait until
1615all data has been written?
1616
1617After writing your last bits of data, set the C<on_drain> callback
1618and destroy the handle in there - with the default setting of
1619C<low_water_mark> this will be called precisely when all data has been
1620written to the socket:
1621
1622 $handle->push_write (...);
1623 $handle->on_drain (sub {
1624 warn "all data submitted to the kernel\n";
1625 undef $handle;
1626 });
1627
1628=back
1629
1630
1456=head1 SUBCLASSING AnyEvent::Handle 1631=head1 SUBCLASSING AnyEvent::Handle
1457 1632
1458In many cases, you might want to subclass AnyEvent::Handle. 1633In many cases, you might want to subclass AnyEvent::Handle.
1459 1634
1460To make this easier, a given version of AnyEvent::Handle uses these 1635To make this easier, a given version of AnyEvent::Handle uses these

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