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Comparing AnyEvent/lib/AnyEvent/Handle.pm (file contents):
Revision 1.85 by root, Thu Aug 21 19:53:19 2008 UTC vs.
Revision 1.132 by elmex, Thu Jul 2 22:25:13 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 = 4.232; 19our $VERSION = 4.45;
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");
63 63
64=head1 METHODS 64=head1 METHODS
65 65
66=over 4 66=over 4
67 67
68=item B<new (%args)> 68=item $handle = B<new> AnyEvent::TLS fh => $filehandle, key => value...
69 69
70The constructor supports these arguments (all as key => value pairs). 70The constructor supports these arguments (all as C<< key => value >> pairs).
71 71
72=over 4 72=over 4
73 73
74=item fh => $filehandle [MANDATORY] 74=item fh => $filehandle [MANDATORY]
75 75
84Set the callback to be called when an end-of-file condition is detected, 84Set the callback to be called when an end-of-file condition is detected,
85i.e. in the case of a socket, when the other side has closed the 85i.e. in the case of a socket, when the other side has closed the
86connection cleanly. 86connection cleanly.
87 87
88For sockets, this just means that the other side has stopped sending data, 88For sockets, this just means that the other side has stopped sending data,
89you can still try to write data, and, in fact, one can return from the eof 89you can still try to write data, and, in fact, one can return from the EOF
90callback and continue writing data, as only the read part has been shut 90callback and continue writing data, as only the read part has been shut
91down. 91down.
92 92
93While not mandatory, it is I<highly> recommended to set an eof callback, 93While not mandatory, it is I<highly> recommended to set an EOF callback,
94otherwise you might end up with a closed socket while you are still 94otherwise you might end up with a closed socket while you are still
95waiting for data. 95waiting for data.
96 96
97If an EOF condition has been detected but no C<on_eof> callback has been 97If an EOF condition has been detected but no C<on_eof> callback has been
98set, then a fatal error will be raised with C<$!> set to <0>. 98set, then a fatal error will be raised with C<$!> set to <0>.
103occured, such as not being able to resolve the hostname, failure to 103occured, such as not being able to resolve the hostname, failure to
104connect or a read error. 104connect or a read error.
105 105
106Some errors are fatal (which is indicated by C<$fatal> being true). On 106Some errors are fatal (which is indicated by C<$fatal> being true). On
107fatal errors the handle object will be shut down and will not be usable 107fatal errors the handle object will be shut down and will not be usable
108(but you are free to look at the current C< ->rbuf >). Examples of fatal 108(but you are free to look at the current C<< ->rbuf >>). Examples of fatal
109errors are an EOF condition with active (but unsatisifable) read watchers 109errors are an EOF condition with active (but unsatisifable) read watchers
110(C<EPIPE>) or I/O errors. 110(C<EPIPE>) or I/O errors.
111 111
112Non-fatal errors can be retried by simply returning, but it is recommended 112Non-fatal errors can be retried by simply returning, but it is recommended
113to simply ignore this parameter and instead abondon the handle object 113to simply ignore this parameter and instead abondon the handle object
127and no read request is in the queue (unlike read queue callbacks, this 127and no read request is in the queue (unlike read queue callbacks, this
128callback will only be called when at least one octet of data is in the 128callback will only be called when at least one octet of data is in the
129read buffer). 129read buffer).
130 130
131To access (and remove data from) the read buffer, use the C<< ->rbuf >> 131To access (and remove data from) the read buffer, use the C<< ->rbuf >>
132method or access the C<$handle->{rbuf}> member directly. 132method or access the C<$handle->{rbuf}> member directly. Note that you
133must not enlarge or modify the read buffer, you can only remove data at
134the beginning from it.
133 135
134When an EOF condition is detected then AnyEvent::Handle will first try to 136When an EOF condition is detected then AnyEvent::Handle will first try to
135feed all the remaining data to the queued callbacks and C<on_read> before 137feed all the remaining data to the queued callbacks and C<on_read> before
136calling the C<on_eof> callback. If no progress can be made, then a fatal 138calling the C<on_eof> callback. If no progress can be made, then a fatal
137error will be raised (with C<$!> set to C<EPIPE>). 139error will be raised (with C<$!> set to C<EPIPE>).
152=item timeout => $fractional_seconds 154=item timeout => $fractional_seconds
153 155
154If non-zero, then this enables an "inactivity" timeout: whenever this many 156If non-zero, then this enables an "inactivity" timeout: whenever this many
155seconds pass without a successful read or write on the underlying file 157seconds 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 158handle, the C<on_timeout> callback will be invoked (and if that one is
157missing, an C<ETIMEDOUT> error will be raised). 159missing, a non-fatal C<ETIMEDOUT> error will be raised).
158 160
159Note that timeout processing is also active when you currently do not have 161Note 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 162any outstanding read or write requests: If you plan to keep the connection
161idle then you should disable the timout temporarily or ignore the timeout 163idle then you should disable the timout temporarily or ignore the timeout
162in the C<on_timeout> callback. 164in the C<on_timeout> callback, in which case AnyEvent::Handle will simply
165restart the timeout.
163 166
164Zero (the default) disables this timeout. 167Zero (the default) disables this timeout.
165 168
166=item on_timeout => $cb->($handle) 169=item on_timeout => $cb->($handle)
167 170
171 174
172=item rbuf_max => <bytes> 175=item rbuf_max => <bytes>
173 176
174If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>) 177If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)
175when the read buffer ever (strictly) exceeds this size. This is useful to 178when the read buffer ever (strictly) exceeds this size. This is useful to
176avoid denial-of-service attacks. 179avoid some forms of denial-of-service attacks.
177 180
178For example, a server accepting connections from untrusted sources should 181For example, a server accepting connections from untrusted sources should
179be configured to accept only so-and-so much data that it cannot act on 182be configured to accept only so-and-so much data that it cannot act on
180(for example, when expecting a line, an attacker could send an unlimited 183(for example, when expecting a line, an attacker could send an unlimited
181amount of data without a callback ever being called as long as the line 184amount of data without a callback ever being called as long as the line
182isn't finished). 185isn't finished).
183 186
184=item autocork => <boolean> 187=item autocork => <boolean>
185 188
186When disabled (the default), then C<push_write> will try to immediately 189When disabled (the default), then C<push_write> will try to immediately
187write the data to the handle if possible. This avoids having to register 190write the data to the handle, if possible. This avoids having to register
188a write watcher and wait for the next event loop iteration, but can be 191a write watcher and wait for the next event loop iteration, but can
189inefficient if you write multiple small chunks (this disadvantage is 192be inefficient if you write multiple small chunks (on the wire, this
190usually avoided by your kernel's nagle algorithm, see C<low_delay>). 193disadvantage is usually avoided by your kernel's nagle algorithm, see
194C<no_delay>, but this option can save costly syscalls).
191 195
192When enabled, then writes will always be queued till the next event loop 196When enabled, then writes will always be queued till the next event loop
193iteration. This is efficient when you do many small writes per iteration, 197iteration. This is efficient when you do many small writes per iteration,
194but less efficient when you do a single write only. 198but less efficient when you do a single write only per iteration (or when
199the write buffer often is full). It also increases write latency.
195 200
196=item no_delay => <boolean> 201=item no_delay => <boolean>
197 202
198When doing small writes on sockets, your operating system kernel might 203When doing small writes on sockets, your operating system kernel might
199wait a bit for more data before actually sending it out. This is called 204wait a bit for more data before actually sending it out. This is called
200the Nagle algorithm, and usually it is beneficial. 205the Nagle algorithm, and usually it is beneficial.
201 206
202In some situations you want as low a delay as possible, which cna be 207In some situations you want as low a delay as possible, which can be
203accomplishd by setting this option to true. 208accomplishd by setting this option to a true value.
204 209
205The default is your opertaing system's default behaviour, this option 210The default is your opertaing system's default behaviour (most likely
206explicitly enables or disables it, if possible. 211enabled), this option explicitly enables or disables it, if possible.
207 212
208=item read_size => <bytes> 213=item read_size => <bytes>
209 214
210The default read block size (the amount of bytes this module will try to read 215The default read block size (the amount of bytes this module will
211during each (loop iteration). Default: C<8192>. 216try to read during each loop iteration, which affects memory
217requirements). Default: C<8192>.
212 218
213=item low_water_mark => <bytes> 219=item low_water_mark => <bytes>
214 220
215Sets the amount of bytes (default: C<0>) that make up an "empty" write 221Sets the amount of bytes (default: C<0>) that make up an "empty" write
216buffer: If the write reaches this size or gets even samller it is 222buffer: If the write reaches this size or gets even samller it is
217considered empty. 223considered empty.
218 224
225Sometimes it can be beneficial (for performance reasons) to add data to
226the write buffer before it is fully drained, but this is a rare case, as
227the operating system kernel usually buffers data as well, so the default
228is good in almost all cases.
229
219=item linger => <seconds> 230=item linger => <seconds>
220 231
221If non-zero (default: C<3600>), then the destructor of the 232If non-zero (default: C<3600>), then the destructor of the
222AnyEvent::Handle object will check wether there is still outstanding write 233AnyEvent::Handle object will check whether there is still outstanding
223data and will install a watcher that will write out this data. No errors 234write data and will install a watcher that will write this data to the
224will be reported (this mostly matches how the operating system treats 235socket. No errors will be reported (this mostly matches how the operating
225outstanding data at socket close time). 236system treats outstanding data at socket close time).
226 237
227This will not work for partial TLS data that could not yet been 238This will not work for partial TLS data that could not be encoded
228encoded. This data will be lost. 239yet. This data will be lost. Calling the C<stoptls> method in time might
240help.
241
242=item common_name => $string
243
244The common name used by some verification methods (most notably SSL/TLS)
245associated with this connection. Usually this is the remote hostname used
246to connect, but can be almost anything.
229 247
230=item tls => "accept" | "connect" | Net::SSLeay::SSL object 248=item tls => "accept" | "connect" | Net::SSLeay::SSL object
231 249
232When this parameter is given, it enables TLS (SSL) mode, that means 250When this parameter is given, it enables TLS (SSL) mode, that means
233AnyEvent will start a TLS handshake and will transparently encrypt/decrypt 251AnyEvent will start a TLS handshake as soon as the conenction has been
234data. 252established and will transparently encrypt/decrypt data afterwards.
235 253
236TLS mode requires Net::SSLeay to be installed (it will be loaded 254TLS mode requires Net::SSLeay to be installed (it will be loaded
237automatically when you try to create a TLS handle). 255automatically when you try to create a TLS handle): this module doesn't
256have a dependency on that module, so if your module requires it, you have
257to add the dependency yourself.
238 258
239Unlike TCP, TLS has a server and client side: for the TLS server side, use 259Unlike TCP, TLS has a server and client side: for the TLS server side, use
240C<accept>, and for the TLS client side of a connection, use C<connect> 260C<accept>, and for the TLS client side of a connection, use C<connect>
241mode. 261mode.
242 262
243You can also provide your own TLS connection object, but you have 263You can also provide your own TLS connection object, but you have
244to make sure that you call either C<Net::SSLeay::set_connect_state> 264to make sure that you call either C<Net::SSLeay::set_connect_state>
245or C<Net::SSLeay::set_accept_state> on it before you pass it to 265or C<Net::SSLeay::set_accept_state> on it before you pass it to
246AnyEvent::Handle. 266AnyEvent::Handle. Also, this module will take ownership of this connection
267object.
247 268
269At some future point, AnyEvent::Handle might switch to another TLS
270implementation, then the option to use your own session object will go
271away.
272
273B<IMPORTANT:> since Net::SSLeay "objects" are really only integers,
274passing in the wrong integer will lead to certain crash. This most often
275happens when one uses a stylish C<< tls => 1 >> and is surprised about the
276segmentation fault.
277
248See the C<starttls> method for when need to start TLS negotiation later. 278See the C<< ->starttls >> method for when need to start TLS negotiation later.
249 279
250=item tls_ctx => $ssl_ctx 280=item tls_ctx => $anyevent_tls
251 281
252Use the given Net::SSLeay::CTX object to create the new TLS connection 282Use the given C<AnyEvent::TLS> object to create the new TLS connection
253(unless a connection object was specified directly). If this parameter is 283(unless a connection object was specified directly). If this parameter is
254missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>. 284missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>.
255 285
286Instead of an object, you can also specify a hash reference with C<< key
287=> value >> pairs. Those will be passed to L<AnyEvent::TLS> to create a
288new TLS context object.
289
256=item json => JSON or JSON::XS object 290=item json => JSON or JSON::XS object
257 291
258This is the json coder object used by the C<json> read and write types. 292This is the json coder object used by the C<json> read and write types.
259 293
260If you don't supply it, then AnyEvent::Handle will create and use a 294If you don't supply it, then AnyEvent::Handle will create and use a
261suitable one, which will write and expect UTF-8 encoded JSON texts. 295suitable one (on demand), which will write and expect UTF-8 encoded JSON
296texts.
262 297
263Note that you are responsible to depend on the JSON module if you want to 298Note that you are responsible to depend on the JSON module if you want to
264use this functionality, as AnyEvent does not have a dependency itself. 299use this functionality, as AnyEvent does not have a dependency itself.
265 300
266=item filter_r => $cb
267
268=item filter_w => $cb
269
270These exist, but are undocumented at this time.
271
272=back 301=back
273 302
274=cut 303=cut
275 304
276sub new { 305sub new {
277 my $class = shift; 306 my $class = shift;
278
279 my $self = bless { @_ }, $class; 307 my $self = bless { @_ }, $class;
280 308
281 $self->{fh} or Carp::croak "mandatory argument fh is missing"; 309 $self->{fh} or Carp::croak "mandatory argument fh is missing";
282 310
283 AnyEvent::Util::fh_nonblocking $self->{fh}, 1; 311 AnyEvent::Util::fh_nonblocking $self->{fh}, 1;
284
285 if ($self->{tls}) {
286 require Net::SSLeay;
287 $self->starttls (delete $self->{tls}, delete $self->{tls_ctx});
288 }
289 312
290 $self->{_activity} = AnyEvent->now; 313 $self->{_activity} = AnyEvent->now;
291 $self->_timeout; 314 $self->_timeout;
292 315
316 $self->no_delay (delete $self->{no_delay}) if exists $self->{no_delay};
317
318 $self->starttls (delete $self->{tls}, delete $self->{tls_ctx})
319 if $self->{tls};
320
293 $self->on_drain (delete $self->{on_drain}) if exists $self->{on_drain}; 321 $self->on_drain (delete $self->{on_drain}) if exists $self->{on_drain};
294 $self->no_delay (delete $self->{no_delay}) if exists $self->{no_delay};
295 322
296 $self->start_read 323 $self->start_read
297 if $self->{on_read}; 324 if $self->{on_read};
298 325
299 $self 326 $self->{fh} && $self
300} 327}
301 328
302sub _shutdown { 329sub _shutdown {
303 my ($self) = @_; 330 my ($self) = @_;
304 331
305 delete $self->{_tw}; 332 delete @$self{qw(_tw _rw _ww fh wbuf on_read _queue)};
306 delete $self->{_rw}; 333 $self->{_eof} = 1; # tell starttls et. al to stop trying
307 delete $self->{_ww};
308 delete $self->{fh};
309 334
310 $self->stoptls; 335 &_freetls;
311
312 delete $self->{on_read};
313 delete $self->{_queue};
314} 336}
315 337
316sub _error { 338sub _error {
317 my ($self, $errno, $fatal) = @_; 339 my ($self, $errno, $fatal) = @_;
318 340
321 343
322 $! = $errno; 344 $! = $errno;
323 345
324 if ($self->{on_error}) { 346 if ($self->{on_error}) {
325 $self->{on_error}($self, $fatal); 347 $self->{on_error}($self, $fatal);
326 } else { 348 } elsif ($self->{fh}) {
327 Carp::croak "AnyEvent::Handle uncaught error: $!"; 349 Carp::croak "AnyEvent::Handle uncaught error: $!";
328 } 350 }
329} 351}
330 352
331=item $fh = $handle->fh 353=item $fh = $handle->fh
332 354
333This method returns the file handle of the L<AnyEvent::Handle> object. 355This method returns the file handle used to create the L<AnyEvent::Handle> object.
334 356
335=cut 357=cut
336 358
337sub fh { $_[0]{fh} } 359sub fh { $_[0]{fh} }
338 360
356 $_[0]{on_eof} = $_[1]; 378 $_[0]{on_eof} = $_[1];
357} 379}
358 380
359=item $handle->on_timeout ($cb) 381=item $handle->on_timeout ($cb)
360 382
361Replace the current C<on_timeout> callback, or disables the callback 383Replace the current C<on_timeout> callback, or disables the callback (but
362(but not the timeout) if C<$cb> = C<undef>. See C<timeout> constructor 384not the timeout) if C<$cb> = C<undef>. See the C<timeout> constructor
363argument. 385argument and method.
364 386
365=cut 387=cut
366 388
367sub on_timeout { 389sub on_timeout {
368 $_[0]{on_timeout} = $_[1]; 390 $_[0]{on_timeout} = $_[1];
369} 391}
370 392
371=item $handle->autocork ($boolean) 393=item $handle->autocork ($boolean)
372 394
373Enables or disables the current autocork behaviour (see C<autocork> 395Enables or disables the current autocork behaviour (see C<autocork>
374constructor argument). 396constructor argument). Changes will only take effect on the next write.
375 397
376=cut 398=cut
399
400sub autocork {
401 $_[0]{autocork} = $_[1];
402}
377 403
378=item $handle->no_delay ($boolean) 404=item $handle->no_delay ($boolean)
379 405
380Enables or disables the C<no_delay> setting (see constructor argument of 406Enables or disables the C<no_delay> setting (see constructor argument of
381the same name for details). 407the same name for details).
474 my ($self, $cb) = @_; 500 my ($self, $cb) = @_;
475 501
476 $self->{on_drain} = $cb; 502 $self->{on_drain} = $cb;
477 503
478 $cb->($self) 504 $cb->($self)
479 if $cb && $self->{low_water_mark} >= length $self->{wbuf}; 505 if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf});
480} 506}
481 507
482=item $handle->push_write ($data) 508=item $handle->push_write ($data)
483 509
484Queues the given scalar to be written. You can push as much data as you 510Queues the given scalar to be written. You can push as much data as you
501 substr $self->{wbuf}, 0, $len, ""; 527 substr $self->{wbuf}, 0, $len, "";
502 528
503 $self->{_activity} = AnyEvent->now; 529 $self->{_activity} = AnyEvent->now;
504 530
505 $self->{on_drain}($self) 531 $self->{on_drain}($self)
506 if $self->{low_water_mark} >= length $self->{wbuf} 532 if $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf})
507 && $self->{on_drain}; 533 && $self->{on_drain};
508 534
509 delete $self->{_ww} unless length $self->{wbuf}; 535 delete $self->{_ww} unless length $self->{wbuf};
510 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) { 536 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
511 $self->_error ($!, 1); 537 $self->_error ($!, 1);
535 561
536 @_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write") 562 @_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write")
537 ->($self, @_); 563 ->($self, @_);
538 } 564 }
539 565
540 if ($self->{filter_w}) { 566 if ($self->{tls}) {
541 $self->{filter_w}($self, \$_[0]); 567 $self->{_tls_wbuf} .= $_[0];
568
569 &_dotls ($self);
542 } else { 570 } else {
543 $self->{wbuf} .= $_[0]; 571 $self->{wbuf} .= $_[0];
544 $self->_drain_wbuf; 572 $self->_drain_wbuf;
545 } 573 }
546} 574}
563=cut 591=cut
564 592
565register_write_type netstring => sub { 593register_write_type netstring => sub {
566 my ($self, $string) = @_; 594 my ($self, $string) = @_;
567 595
568 sprintf "%d:%s,", (length $string), $string 596 (length $string) . ":$string,"
569}; 597};
570 598
571=item packstring => $format, $data 599=item packstring => $format, $data
572 600
573An octet string prefixed with an encoded length. The encoding C<$format> 601An octet string prefixed with an encoded length. The encoding C<$format>
751 ) { 779 ) {
752 $self->_error (&Errno::ENOSPC, 1), return; 780 $self->_error (&Errno::ENOSPC, 1), return;
753 } 781 }
754 782
755 while () { 783 while () {
784 # we need to use a separate tls read buffer, as we must not receive data while
785 # we are draining the buffer, and this can only happen with TLS.
786 $self->{rbuf} .= delete $self->{_tls_rbuf} if exists $self->{_tls_rbuf};
787
756 my $len = length $self->{rbuf}; 788 my $len = length $self->{rbuf};
757 789
758 if (my $cb = shift @{ $self->{_queue} }) { 790 if (my $cb = shift @{ $self->{_queue} }) {
759 unless ($cb->($self)) { 791 unless ($cb->($self)) {
760 if ($self->{_eof}) { 792 if ($self->{_eof}) {
782 814
783 last; # more data might arrive 815 last; # more data might arrive
784 } 816 }
785 } else { 817 } else {
786 # read side becomes idle 818 # read side becomes idle
787 delete $self->{_rw}; 819 delete $self->{_rw} unless $self->{tls};
788 last; 820 last;
789 } 821 }
790 } 822 }
791 823
792 if ($self->{_eof}) { 824 if ($self->{_eof}) {
821 853
822=item $handle->rbuf 854=item $handle->rbuf
823 855
824Returns the read buffer (as a modifiable lvalue). 856Returns the read buffer (as a modifiable lvalue).
825 857
826You can access the read buffer directly as the C<< ->{rbuf} >> member, if 858You can access the read buffer directly as the C<< ->{rbuf} >>
827you want. 859member, if you want. However, the only operation allowed on the
860read buffer (apart from looking at it) is removing data from its
861beginning. Otherwise modifying or appending to it is not allowed and will
862lead to hard-to-track-down bugs.
828 863
829NOTE: The read buffer should only be used or modified if the C<on_read>, 864NOTE: The read buffer should only be used or modified if the C<on_read>,
830C<push_read> or C<unshift_read> methods are used. The other read methods 865C<push_read> or C<unshift_read> methods are used. The other read methods
831automatically manage the read buffer. 866automatically manage the read buffer.
832 867
1087An octet string prefixed with an encoded length. The encoding C<$format> 1122An octet string prefixed with an encoded length. The encoding C<$format>
1088uses the same format as a Perl C<pack> format, but must specify a single 1123uses the same format as a Perl C<pack> format, but must specify a single
1089integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an 1124integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
1090optional C<!>, C<< < >> or C<< > >> modifier). 1125optional C<!>, C<< < >> or C<< > >> modifier).
1091 1126
1092DNS over TCP uses a prefix of C<n>, EPP uses a prefix of C<N>. 1127For example, DNS over TCP uses a prefix of C<n> (2 octet network order),
1128EPP uses a prefix of C<N> (4 octtes).
1093 1129
1094Example: read a block of data prefixed by its length in BER-encoded 1130Example: read a block of data prefixed by its length in BER-encoded
1095format (very efficient). 1131format (very efficient).
1096 1132
1097 $handle->push_read (packstring => "w", sub { 1133 $handle->push_read (packstring => "w", sub {
1127 } 1163 }
1128}; 1164};
1129 1165
1130=item json => $cb->($handle, $hash_or_arrayref) 1166=item json => $cb->($handle, $hash_or_arrayref)
1131 1167
1132Reads a JSON object or array, decodes it and passes it to the callback. 1168Reads a JSON object or array, decodes it and passes it to the
1169callback. When a parse error occurs, an C<EBADMSG> error will be raised.
1133 1170
1134If a C<json> object was passed to the constructor, then that will be used 1171If a C<json> object was passed to the constructor, then that will be used
1135for the final decode, otherwise it will create a JSON coder expecting UTF-8. 1172for the final decode, otherwise it will create a JSON coder expecting UTF-8.
1136 1173
1137This read type uses the incremental parser available with JSON version 1174This read type uses the incremental parser available with JSON version
1154 my $rbuf = \$self->{rbuf}; 1191 my $rbuf = \$self->{rbuf};
1155 1192
1156 my $json = $self->{json} ||= JSON->new->utf8; 1193 my $json = $self->{json} ||= JSON->new->utf8;
1157 1194
1158 sub { 1195 sub {
1159 my $ref = $json->incr_parse ($self->{rbuf}); 1196 my $ref = eval { $json->incr_parse ($self->{rbuf}) };
1160 1197
1161 if ($ref) { 1198 if ($ref) {
1162 $self->{rbuf} = $json->incr_text; 1199 $self->{rbuf} = $json->incr_text;
1163 $json->incr_text = ""; 1200 $json->incr_text = "";
1164 $cb->($self, $ref); 1201 $cb->($self, $ref);
1165 1202
1166 1 1203 1
1204 } elsif ($@) {
1205 # error case
1206 $json->incr_skip;
1207
1208 $self->{rbuf} = $json->incr_text;
1209 $json->incr_text = "";
1210
1211 $self->_error (&Errno::EBADMSG);
1212
1213 ()
1167 } else { 1214 } else {
1168 $self->{rbuf} = ""; 1215 $self->{rbuf} = "";
1216
1169 () 1217 ()
1170 } 1218 }
1171 } 1219 }
1172}; 1220};
1173 1221
1250Note that AnyEvent::Handle will automatically C<start_read> for you when 1298Note that AnyEvent::Handle will automatically C<start_read> for you when
1251you change the C<on_read> callback or push/unshift a read callback, and it 1299you change the C<on_read> callback or push/unshift a read callback, and it
1252will automatically C<stop_read> for you when neither C<on_read> is set nor 1300will automatically C<stop_read> for you when neither C<on_read> is set nor
1253there are any read requests in the queue. 1301there are any read requests in the queue.
1254 1302
1303These methods will have no effect when in TLS mode (as TLS doesn't support
1304half-duplex connections).
1305
1255=cut 1306=cut
1256 1307
1257sub stop_read { 1308sub stop_read {
1258 my ($self) = @_; 1309 my ($self) = @_;
1259 1310
1260 delete $self->{_rw}; 1311 delete $self->{_rw} unless $self->{tls};
1261} 1312}
1262 1313
1263sub start_read { 1314sub start_read {
1264 my ($self) = @_; 1315 my ($self) = @_;
1265 1316
1266 unless ($self->{_rw} || $self->{_eof}) { 1317 unless ($self->{_rw} || $self->{_eof}) {
1267 Scalar::Util::weaken $self; 1318 Scalar::Util::weaken $self;
1268 1319
1269 $self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub { 1320 $self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub {
1270 my $rbuf = $self->{filter_r} ? \my $buf : \$self->{rbuf}; 1321 my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf});
1271 my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf; 1322 my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf;
1272 1323
1273 if ($len > 0) { 1324 if ($len > 0) {
1274 $self->{_activity} = AnyEvent->now; 1325 $self->{_activity} = AnyEvent->now;
1275 1326
1276 $self->{filter_r} 1327 if ($self->{tls}) {
1277 ? $self->{filter_r}($self, $rbuf) 1328 Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf);
1278 : $self->{_in_drain} || $self->_drain_rbuf; 1329
1330 &_dotls ($self);
1331 } else {
1332 $self->_drain_rbuf unless $self->{_in_drain};
1333 }
1279 1334
1280 } elsif (defined $len) { 1335 } elsif (defined $len) {
1281 delete $self->{_rw}; 1336 delete $self->{_rw};
1282 $self->{_eof} = 1; 1337 $self->{_eof} = 1;
1283 $self->_drain_rbuf unless $self->{_in_drain}; 1338 $self->_drain_rbuf unless $self->{_in_drain};
1287 } 1342 }
1288 }); 1343 });
1289 } 1344 }
1290} 1345}
1291 1346
1347# poll the write BIO and send the data if applicable
1292sub _dotls { 1348sub _dotls {
1293 my ($self) = @_; 1349 my ($self) = @_;
1294 1350
1295 my $buf; 1351 my $tmp;
1296 1352
1297 if (length $self->{_tls_wbuf}) { 1353 if (length $self->{_tls_wbuf}) {
1298 while ((my $len = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) { 1354 while (($tmp = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) {
1299 substr $self->{_tls_wbuf}, 0, $len, ""; 1355 substr $self->{_tls_wbuf}, 0, $tmp, "";
1300 } 1356 }
1301 } 1357 }
1302 1358
1303 if (length ($buf = Net::SSLeay::BIO_read ($self->{_wbio}))) {
1304 $self->{wbuf} .= $buf;
1305 $self->_drain_wbuf;
1306 }
1307
1308 while (defined ($buf = Net::SSLeay::read ($self->{tls}))) { 1359 while (defined ($tmp = Net::SSLeay::read ($self->{tls}))) {
1309 if (length $buf) { 1360 unless (length $tmp) {
1310 $self->{rbuf} .= $buf;
1311 $self->_drain_rbuf unless $self->{_in_drain};
1312 } else {
1313 # let's treat SSL-eof as we treat normal EOF 1361 # let's treat SSL-eof as we treat normal EOF
1362 delete $self->{_rw};
1314 $self->{_eof} = 1; 1363 $self->{_eof} = 1;
1315 $self->_shutdown; 1364 &_freetls;
1316 return;
1317 } 1365 }
1318 }
1319 1366
1367 $self->{_tls_rbuf} .= $tmp;
1368 $self->_drain_rbuf unless $self->{_in_drain};
1369 $self->{tls} or return; # tls session might have gone away in callback
1370 }
1371
1320 my $err = Net::SSLeay::get_error ($self->{tls}, -1); 1372 $tmp = Net::SSLeay::get_error ($self->{tls}, -1);
1321 1373
1322 if ($err!= Net::SSLeay::ERROR_WANT_READ ()) { 1374 if ($tmp != Net::SSLeay::ERROR_WANT_READ ()) {
1323 if ($err == Net::SSLeay::ERROR_SYSCALL ()) { 1375 if ($tmp == Net::SSLeay::ERROR_SYSCALL ()) {
1324 return $self->_error ($!, 1); 1376 return $self->_error ($!, 1);
1325 } elsif ($err == Net::SSLeay::ERROR_SSL ()) { 1377 } elsif ($tmp == Net::SSLeay::ERROR_SSL ()) {
1326 return $self->_error (&Errno::EIO, 1); 1378 return $self->_error (&Errno::EIO, 1);
1327 } 1379 }
1328 1380
1329 # all others are fine for our purposes 1381 # all other errors are fine for our purposes
1382 }
1383
1384 while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) {
1385 $self->{wbuf} .= $tmp;
1386 $self->_drain_wbuf;
1330 } 1387 }
1331} 1388}
1332 1389
1333=item $handle->starttls ($tls[, $tls_ctx]) 1390=item $handle->starttls ($tls[, $tls_ctx])
1334 1391
1337C<starttls>. 1394C<starttls>.
1338 1395
1339The first argument is the same as the C<tls> constructor argument (either 1396The first argument is the same as the C<tls> constructor argument (either
1340C<"connect">, C<"accept"> or an existing Net::SSLeay object). 1397C<"connect">, C<"accept"> or an existing Net::SSLeay object).
1341 1398
1342The second argument is the optional C<Net::SSLeay::CTX> object that is 1399The second argument is the optional C<AnyEvent::TLS> object that is used
1343used when AnyEvent::Handle has to create its own TLS connection object. 1400when AnyEvent::Handle has to create its own TLS connection object, or
1401a hash reference with C<< key => value >> pairs that will be used to
1402construct a new context.
1344 1403
1345The TLS connection object will end up in C<< $handle->{tls} >> after this 1404The TLS connection object will end up in C<< $handle->{tls} >>, the TLS
1346call and can be used or changed to your liking. Note that the handshake 1405context in C<< $handle->{tls_ctx} >> after this call and can be used or
1347might have already started when this function returns. 1406changed to your liking. Note that the handshake might have already started
1407when this function returns.
1408
1409If it an error to start a TLS handshake more than once per
1410AnyEvent::Handle object (this is due to bugs in OpenSSL).
1348 1411
1349=cut 1412=cut
1350 1413
1351sub starttls { 1414sub starttls {
1352 my ($self, $ssl, $ctx) = @_; 1415 my ($self, $ssl, $ctx) = @_;
1353 1416
1354 $self->stoptls; 1417 require Net::SSLeay;
1355 1418
1356 if ($ssl eq "accept") { 1419 Carp::croak "it is an error to call starttls more than once on an AnyEvent::Handle object"
1357 $ssl = Net::SSLeay::new ($ctx || TLS_CTX ()); 1420 if $self->{tls};
1358 Net::SSLeay::set_accept_state ($ssl); 1421
1359 } elsif ($ssl eq "connect") { 1422 $ctx ||= $self->{tls_ctx};
1360 $ssl = Net::SSLeay::new ($ctx || TLS_CTX ()); 1423
1361 Net::SSLeay::set_connect_state ($ssl); 1424 if ("HASH" eq ref $ctx) {
1425 require AnyEvent::TLS;
1426
1427 local $Carp::CarpLevel = 1; # skip ourselves when creating a new context
1428 $ctx = new AnyEvent::TLS %$ctx;
1429 }
1362 } 1430
1363 1431 $self->{tls_ctx} = $ctx || TLS_CTX ();
1364 $self->{tls} = $ssl; 1432 $self->{tls} = $ssl = $self->{tls_ctx}->_get_session ($ssl, $self);
1365 1433
1366 # basically, this is deep magic (because SSL_read should have the same issues) 1434 # basically, this is deep magic (because SSL_read should have the same issues)
1367 # but the openssl maintainers basically said: "trust us, it just works". 1435 # but the openssl maintainers basically said: "trust us, it just works".
1368 # (unfortunately, we have to hardcode constants because the abysmally misdesigned 1436 # (unfortunately, we have to hardcode constants because the abysmally misdesigned
1369 # and mismaintained ssleay-module doesn't even offer them). 1437 # and mismaintained ssleay-module doesn't even offer them).
1370 # http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html 1438 # http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html
1439 #
1440 # in short: this is a mess.
1441 #
1442 # note that we do not try to keep the length constant between writes as we are required to do.
1443 # we assume that most (but not all) of this insanity only applies to non-blocking cases,
1444 # and we drive openssl fully in blocking mode here. Or maybe we don't - openssl seems to
1445 # have identity issues in that area.
1371 Net::SSLeay::CTX_set_mode ($self->{tls}, 1446# Net::SSLeay::CTX_set_mode ($ssl,
1372 (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1) 1447# (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)
1373 | (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2)); 1448# | (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2));
1449 Net::SSLeay::CTX_set_mode ($ssl, 1|2);
1374 1450
1375 $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); 1451 $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1376 $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); 1452 $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1377 1453
1378 Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio}); 1454 Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio});
1379 1455
1380 $self->{filter_w} = sub { 1456 &_dotls; # need to trigger the initial handshake
1381 $_[0]{_tls_wbuf} .= ${$_[1]}; 1457 $self->start_read; # make sure we actually do read
1382 &_dotls;
1383 };
1384 $self->{filter_r} = sub {
1385 Net::SSLeay::BIO_write ($_[0]{_rbio}, ${$_[1]});
1386 &_dotls;
1387 };
1388} 1458}
1389 1459
1390=item $handle->stoptls 1460=item $handle->stoptls
1391 1461
1392Destroys the SSL connection, if any. Partial read or write data will be 1462Shuts down the SSL connection - this makes a proper EOF handshake by
1393lost. 1463sending a close notify to the other side, but since OpenSSL doesn't
1464support non-blocking shut downs, it is not possible to re-use the stream
1465afterwards.
1394 1466
1395=cut 1467=cut
1396 1468
1397sub stoptls { 1469sub stoptls {
1398 my ($self) = @_; 1470 my ($self) = @_;
1399 1471
1400 Net::SSLeay::free (delete $self->{tls}) if $self->{tls}; 1472 if ($self->{tls}) {
1473 Net::SSLeay::shutdown ($self->{tls});
1401 1474
1402 delete $self->{_rbio}; 1475 &_dotls;
1403 delete $self->{_wbio}; 1476
1404 delete $self->{_tls_wbuf}; 1477 # we don't give a shit. no, we do, but we can't. no...
1405 delete $self->{filter_r}; 1478 # we, we... have to use openssl :/
1406 delete $self->{filter_w}; 1479 &_freetls;
1480 }
1481}
1482
1483sub _freetls {
1484 my ($self) = @_;
1485
1486 return unless $self->{tls};
1487
1488 $self->{tls_ctx}->_put_session (delete $self->{tls});
1489
1490 delete @$self{qw(_rbio _wbio _tls_wbuf)};
1407} 1491}
1408 1492
1409sub DESTROY { 1493sub DESTROY {
1410 my $self = shift; 1494 my ($self) = @_;
1411 1495
1412 $self->stoptls; 1496 &_freetls;
1413 1497
1414 my $linger = exists $self->{linger} ? $self->{linger} : 3600; 1498 my $linger = exists $self->{linger} ? $self->{linger} : 3600;
1415 1499
1416 if ($linger && length $self->{wbuf}) { 1500 if ($linger && length $self->{wbuf}) {
1417 my $fh = delete $self->{fh}; 1501 my $fh = delete $self->{fh};
1432 @linger = (); 1516 @linger = ();
1433 }); 1517 });
1434 } 1518 }
1435} 1519}
1436 1520
1521=item $handle->destroy
1522
1523Shuts down the handle object as much as possible - this call ensures that
1524no further callbacks will be invoked and resources will be freed as much
1525as possible. You must not call any methods on the object afterwards.
1526
1527Normally, you can just "forget" any references to an AnyEvent::Handle
1528object and it will simply shut down. This works in fatal error and EOF
1529callbacks, as well as code outside. It does I<NOT> work in a read or write
1530callback, so when you want to destroy the AnyEvent::Handle object from
1531within such an callback. You I<MUST> call C<< ->destroy >> explicitly in
1532that case.
1533
1534The handle might still linger in the background and write out remaining
1535data, as specified by the C<linger> option, however.
1536
1537=cut
1538
1539sub destroy {
1540 my ($self) = @_;
1541
1542 $self->DESTROY;
1543 %$self = ();
1544}
1545
1437=item AnyEvent::Handle::TLS_CTX 1546=item AnyEvent::Handle::TLS_CTX
1438 1547
1439This function creates and returns the Net::SSLeay::CTX object used by 1548This function creates and returns the AnyEvent::TLS object used by default
1440default for TLS mode. 1549for TLS mode.
1441 1550
1442The context is created like this: 1551The context is created by calling L<AnyEvent::TLS> without any arguments.
1443
1444 Net::SSLeay::load_error_strings;
1445 Net::SSLeay::SSLeay_add_ssl_algorithms;
1446 Net::SSLeay::randomize;
1447
1448 my $CTX = Net::SSLeay::CTX_new;
1449
1450 Net::SSLeay::CTX_set_options $CTX, Net::SSLeay::OP_ALL
1451 1552
1452=cut 1553=cut
1453 1554
1454our $TLS_CTX; 1555our $TLS_CTX;
1455 1556
1456sub TLS_CTX() { 1557sub TLS_CTX() {
1457 $TLS_CTX || do { 1558 $TLS_CTX ||= do {
1458 require Net::SSLeay; 1559 require AnyEvent::TLS;
1459 1560
1460 Net::SSLeay::load_error_strings (); 1561 new AnyEvent::TLS
1461 Net::SSLeay::SSLeay_add_ssl_algorithms ();
1462 Net::SSLeay::randomize ();
1463
1464 $TLS_CTX = Net::SSLeay::CTX_new ();
1465
1466 Net::SSLeay::CTX_set_options ($TLS_CTX, Net::SSLeay::OP_ALL ());
1467
1468 $TLS_CTX
1469 } 1562 }
1470} 1563}
1471 1564
1472=back 1565=back
1566
1567
1568=head1 NONFREQUENTLY ASKED QUESTIONS
1569
1570=over 4
1571
1572=item I C<undef> the AnyEvent::Handle reference inside my callback and
1573still get further invocations!
1574
1575That's because AnyEvent::Handle keeps a reference to itself when handling
1576read or write callbacks.
1577
1578It is only safe to "forget" the reference inside EOF or error callbacks,
1579from within all other callbacks, you need to explicitly call the C<<
1580->destroy >> method.
1581
1582=item I get different callback invocations in TLS mode/Why can't I pause
1583reading?
1584
1585Unlike, say, TCP, TLS connections do not consist of two independent
1586communication channels, one for each direction. Or put differently. The
1587read and write directions are not independent of each other: you cannot
1588write data unless you are also prepared to read, and vice versa.
1589
1590This can mean than, in TLS mode, you might get C<on_error> or C<on_eof>
1591callback invocations when you are not expecting any read data - the reason
1592is that AnyEvent::Handle always reads in TLS mode.
1593
1594During the connection, you have to make sure that you always have a
1595non-empty read-queue, or an C<on_read> watcher. At the end of the
1596connection (or when you no longer want to use it) you can call the
1597C<destroy> method.
1598
1599=item How do I read data until the other side closes the connection?
1600
1601If you just want to read your data into a perl scalar, the easiest way
1602to achieve this is by setting an C<on_read> callback that does nothing,
1603clearing the C<on_eof> callback and in the C<on_error> callback, the data
1604will be in C<$_[0]{rbuf}>:
1605
1606 $handle->on_read (sub { });
1607 $handle->on_eof (undef);
1608 $handle->on_error (sub {
1609 my $data = delete $_[0]{rbuf};
1610 undef $handle;
1611 });
1612
1613The reason to use C<on_error> is that TCP connections, due to latencies
1614and packets loss, might get closed quite violently with an error, when in
1615fact, all data has been received.
1616
1617It is usually better to use acknowledgements when transferring data,
1618to make sure the other side hasn't just died and you got the data
1619intact. This is also one reason why so many internet protocols have an
1620explicit QUIT command.
1621
1622=item I don't want to destroy the handle too early - how do I wait until
1623all data has been written?
1624
1625After writing your last bits of data, set the C<on_drain> callback
1626and destroy the handle in there - with the default setting of
1627C<low_water_mark> this will be called precisely when all data has been
1628written to the socket:
1629
1630 $handle->push_write (...);
1631 $handle->on_drain (sub {
1632 warn "all data submitted to the kernel\n";
1633 undef $handle;
1634 });
1635
1636=back
1637
1473 1638
1474=head1 SUBCLASSING AnyEvent::Handle 1639=head1 SUBCLASSING AnyEvent::Handle
1475 1640
1476In many cases, you might want to subclass AnyEvent::Handle. 1641In many cases, you might want to subclass AnyEvent::Handle.
1477 1642

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