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Revision 1.56 by root, Wed Jun 4 09:55:16 2008 UTC vs.
Revision 1.130 by root, Mon Jun 29 21:00:32 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(WSAEWOULDBLOCK); 7use AnyEvent::Util qw(WSAEWOULDBLOCK);
8use Scalar::Util (); 8use Scalar::Util ();
9use Carp (); 9use Carp ();
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 = 4.12; 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");
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 detcted, 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 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.
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>.
87 99
88=item on_error => $cb->($handle, $fatal) 100=item on_error => $cb->($handle, $fatal)
89 101
90This is the error callback, which is called when, well, some error 102This is the error callback, which is called when, well, some error
91occured, such as not being able to resolve the hostname, failure to 103occured, such as not being able to resolve the hostname, failure to
92connect or a read error. 104connect or a read error.
93 105
94Some errors are fatal (which is indicated by C<$fatal> being true). On 106Some errors are fatal (which is indicated by C<$fatal> being true). On
95fatal errors the handle object will be shut down and will not be 107fatal errors the handle object will be shut down and will not be usable
108(but you are free to look at the current C<< ->rbuf >>). Examples of fatal
109errors are an EOF condition with active (but unsatisifable) read watchers
110(C<EPIPE>) or I/O errors.
111
96usable. Non-fatal errors can be retried by simply returning, but it is 112Non-fatal errors can be retried by simply returning, but it is recommended
97recommended to simply ignore this parameter and instead abondon the handle 113to simply ignore this parameter and instead abondon the handle object
98object when this callback is invoked. 114when this callback is invoked. Examples of non-fatal errors are timeouts
115C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>).
99 116
100On callback entrance, the value of C<$!> contains the operating system 117On callback entrance, the value of C<$!> contains the operating system
101error (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT> or C<EBADMSG>). 118error (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT> or C<EBADMSG>).
102 119
103While 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
105C<croak>. 122C<croak>.
106 123
107=item on_read => $cb->($handle) 124=item on_read => $cb->($handle)
108 125
109This sets the default read callback, which is called when data arrives 126This sets the default read callback, which is called when data arrives
110and 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).
111 130
112To 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 >>
113method 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.
114 135
115When 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
116feed 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
117calling 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
118error will be raised (with C<$!> set to C<EPIPE>). 139error will be raised (with C<$!> set to C<EPIPE>).
122This sets the callback that is called when the write buffer becomes empty 143This sets the callback that is called when the write buffer becomes empty
123(or when the callback is set and the buffer is empty already). 144(or when the callback is set and the buffer is empty already).
124 145
125To append to the write buffer, use the C<< ->push_write >> method. 146To append to the write buffer, use the C<< ->push_write >> method.
126 147
148This callback is useful when you don't want to put all of your write data
149into the queue at once, for example, when you want to write the contents
150of some file to the socket you might not want to read the whole file into
151memory and push it into the queue, but instead only read more data from
152the file when the write queue becomes empty.
153
127=item timeout => $fractional_seconds 154=item timeout => $fractional_seconds
128 155
129If non-zero, then this enables an "inactivity" timeout: whenever this many 156If non-zero, then this enables an "inactivity" timeout: whenever this many
130seconds pass without a successful read or write on the underlying file 157seconds pass without a successful read or write on the underlying file
131handle, 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
132missing, an C<ETIMEDOUT> error will be raised). 159missing, a non-fatal C<ETIMEDOUT> error will be raised).
133 160
134Note 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
135any 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
136idle then you should disable the timout temporarily or ignore the timeout 163idle then you should disable the timout temporarily or ignore the timeout
137in the C<on_timeout> callback. 164in the C<on_timeout> callback, in which case AnyEvent::Handle will simply
165restart the timeout.
138 166
139Zero (the default) disables this timeout. 167Zero (the default) disables this timeout.
140 168
141=item on_timeout => $cb->($handle) 169=item on_timeout => $cb->($handle)
142 170
146 174
147=item rbuf_max => <bytes> 175=item rbuf_max => <bytes>
148 176
149If 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>)
150when 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
151avoid denial-of-service attacks. 179avoid some forms of denial-of-service attacks.
152 180
153For example, a server accepting connections from untrusted sources should 181For example, a server accepting connections from untrusted sources should
154be 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
155(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
156amount 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
157isn't finished). 185isn't finished).
158 186
187=item autocork => <boolean>
188
189When disabled (the default), then C<push_write> will try to immediately
190write the data to the handle, if possible. This avoids having to register
191a write watcher and wait for the next event loop iteration, but can
192be inefficient if you write multiple small chunks (on the wire, this
193disadvantage is usually avoided by your kernel's nagle algorithm, see
194C<no_delay>, but this option can save costly syscalls).
195
196When enabled, then writes will always be queued till the next event loop
197iteration. This is efficient when you do many small writes per iteration,
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.
200
201=item no_delay => <boolean>
202
203When doing small writes on sockets, your operating system kernel might
204wait a bit for more data before actually sending it out. This is called
205the Nagle algorithm, and usually it is beneficial.
206
207In some situations you want as low a delay as possible, which can be
208accomplishd by setting this option to a true value.
209
210The default is your opertaing system's default behaviour (most likely
211enabled), this option explicitly enables or disables it, if possible.
212
159=item read_size => <bytes> 213=item read_size => <bytes>
160 214
161The 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
162during each (loop iteration). Default: C<8192>. 216try to read during each loop iteration, which affects memory
217requirements). Default: C<8192>.
163 218
164=item low_water_mark => <bytes> 219=item low_water_mark => <bytes>
165 220
166Sets 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
167buffer: 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
168considered empty. 223considered empty.
169 224
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
230=item linger => <seconds>
231
232If non-zero (default: C<3600>), then the destructor of the
233AnyEvent::Handle object will check whether there is still outstanding
234write data and will install a watcher that will write this data to the
235socket. No errors will be reported (this mostly matches how the operating
236system treats outstanding data at socket close time).
237
238This will not work for partial TLS data that could not be encoded
239yet. This data will be lost. Calling the C<stoptls> method in time might
240help.
241
170=item tls => "accept" | "connect" | Net::SSLeay::SSL object 242=item tls => "accept" | "connect" | Net::SSLeay::SSL object
171 243
172When this parameter is given, it enables TLS (SSL) mode, that means it 244When this parameter is given, it enables TLS (SSL) mode, that means
173will start making tls handshake and will transparently encrypt/decrypt 245AnyEvent will start a TLS handshake as soon as the conenction has been
174data. 246established and will transparently encrypt/decrypt data afterwards.
175 247
176TLS mode requires Net::SSLeay to be installed (it will be loaded 248TLS mode requires Net::SSLeay to be installed (it will be loaded
177automatically when you try to create a TLS handle). 249automatically when you try to create a TLS handle): this module doesn't
250have a dependency on that module, so if your module requires it, you have
251to add the dependency yourself.
178 252
179For the TLS server side, use C<accept>, and for the TLS client side of a 253Unlike TCP, TLS has a server and client side: for the TLS server side, use
180connection, use C<connect> mode. 254C<accept>, and for the TLS client side of a connection, use C<connect>
255mode.
181 256
182You can also provide your own TLS connection object, but you have 257You can also provide your own TLS connection object, but you have
183to make sure that you call either C<Net::SSLeay::set_connect_state> 258to make sure that you call either C<Net::SSLeay::set_connect_state>
184or C<Net::SSLeay::set_accept_state> on it before you pass it to 259or C<Net::SSLeay::set_accept_state> on it before you pass it to
185AnyEvent::Handle. 260AnyEvent::Handle.
186 261
262B<IMPORTANT:> since Net::SSLeay "objects" are really only integers,
263passing in the wrong integer will lead to certain crash. This most often
264happens when one uses a stylish C<< tls => 1 >> and is surprised about the
265segmentation fault.
266
187See the C<starttls> method if you need to start TLs negotiation later. 267See the C<< ->starttls >> method for when need to start TLS negotiation later.
188 268
189=item tls_ctx => $ssl_ctx 269=item tls_ctx => $ssl_ctx
190 270
191Use the given Net::SSLeay::CTX object to create the new TLS connection 271Use the given C<Net::SSLeay::CTX> object to create the new TLS connection
192(unless a connection object was specified directly). If this parameter is 272(unless a connection object was specified directly). If this parameter is
193missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>. 273missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>.
194 274
195=item json => JSON or JSON::XS object 275=item json => JSON or JSON::XS object
196 276
197This is the json coder object used by the C<json> read and write types. 277This is the json coder object used by the C<json> read and write types.
198 278
199If you don't supply it, then AnyEvent::Handle will create and use a 279If you don't supply it, then AnyEvent::Handle will create and use a
200suitable one, which will write and expect UTF-8 encoded JSON texts. 280suitable one (on demand), which will write and expect UTF-8 encoded JSON
281texts.
201 282
202Note that you are responsible to depend on the JSON module if you want to 283Note that you are responsible to depend on the JSON module if you want to
203use this functionality, as AnyEvent does not have a dependency itself. 284use this functionality, as AnyEvent does not have a dependency itself.
204 285
205=item filter_r => $cb
206
207=item filter_w => $cb
208
209These exist, but are undocumented at this time.
210
211=back 286=back
212 287
213=cut 288=cut
214 289
215sub new { 290sub new {
219 294
220 $self->{fh} or Carp::croak "mandatory argument fh is missing"; 295 $self->{fh} or Carp::croak "mandatory argument fh is missing";
221 296
222 AnyEvent::Util::fh_nonblocking $self->{fh}, 1; 297 AnyEvent::Util::fh_nonblocking $self->{fh}, 1;
223 298
224 if ($self->{tls}) {
225 require Net::SSLeay;
226 $self->starttls (delete $self->{tls}, delete $self->{tls_ctx}); 299 $self->starttls (delete $self->{tls}, delete $self->{tls_ctx})
227 } 300 if $self->{tls};
228
229# $self->on_eof (delete $self->{on_eof} ) if $self->{on_eof}; # nop
230# $self->on_error (delete $self->{on_error}) if $self->{on_error}; # nop
231# $self->on_read (delete $self->{on_read} ) if $self->{on_read}; # nop
232 $self->on_drain (delete $self->{on_drain}) if $self->{on_drain};
233 301
234 $self->{_activity} = AnyEvent->now; 302 $self->{_activity} = AnyEvent->now;
235 $self->_timeout; 303 $self->_timeout;
236 304
305 $self->on_drain (delete $self->{on_drain}) if exists $self->{on_drain};
306 $self->no_delay (delete $self->{no_delay}) if exists $self->{no_delay};
307
237 $self->start_read; 308 $self->start_read
309 if $self->{on_read};
238 310
239 $self 311 $self
240} 312}
241 313
242sub _shutdown { 314sub _shutdown {
243 my ($self) = @_; 315 my ($self) = @_;
244 316
245 delete $self->{_tw}; 317 delete @$self{qw(_tw _rw _ww fh rbuf wbuf on_read _queue)};
246 delete $self->{_rw};
247 delete $self->{_ww};
248 delete $self->{fh};
249 318
250 $self->stoptls; 319 &_freetls;
251} 320}
252 321
253sub _error { 322sub _error {
254 my ($self, $errno, $fatal) = @_; 323 my ($self, $errno, $fatal) = @_;
255 324
258 327
259 $! = $errno; 328 $! = $errno;
260 329
261 if ($self->{on_error}) { 330 if ($self->{on_error}) {
262 $self->{on_error}($self, $fatal); 331 $self->{on_error}($self, $fatal);
263 } else { 332 } elsif ($self->{fh}) {
264 Carp::croak "AnyEvent::Handle uncaught error: $!"; 333 Carp::croak "AnyEvent::Handle uncaught error: $!";
265 } 334 }
266} 335}
267 336
268=item $fh = $handle->fh 337=item $fh = $handle->fh
269 338
270This method returns the file handle of the L<AnyEvent::Handle> object. 339This method returns the file handle used to create the L<AnyEvent::Handle> object.
271 340
272=cut 341=cut
273 342
274sub fh { $_[0]{fh} } 343sub fh { $_[0]{fh} }
275 344
293 $_[0]{on_eof} = $_[1]; 362 $_[0]{on_eof} = $_[1];
294} 363}
295 364
296=item $handle->on_timeout ($cb) 365=item $handle->on_timeout ($cb)
297 366
298Replace the current C<on_timeout> callback, or disables the callback 367Replace the current C<on_timeout> callback, or disables the callback (but
299(but not the timeout) if C<$cb> = C<undef>. See C<timeout> constructor 368not the timeout) if C<$cb> = C<undef>. See the C<timeout> constructor
300argument. 369argument and method.
301 370
302=cut 371=cut
303 372
304sub on_timeout { 373sub on_timeout {
305 $_[0]{on_timeout} = $_[1]; 374 $_[0]{on_timeout} = $_[1];
375}
376
377=item $handle->autocork ($boolean)
378
379Enables or disables the current autocork behaviour (see C<autocork>
380constructor argument). Changes will only take effect on the next write.
381
382=cut
383
384sub autocork {
385 $_[0]{autocork} = $_[1];
386}
387
388=item $handle->no_delay ($boolean)
389
390Enables or disables the C<no_delay> setting (see constructor argument of
391the same name for details).
392
393=cut
394
395sub no_delay {
396 $_[0]{no_delay} = $_[1];
397
398 eval {
399 local $SIG{__DIE__};
400 setsockopt $_[0]{fh}, &Socket::IPPROTO_TCP, &Socket::TCP_NODELAY, int $_[1];
401 };
306} 402}
307 403
308############################################################################# 404#############################################################################
309 405
310=item $handle->timeout ($seconds) 406=item $handle->timeout ($seconds)
388 my ($self, $cb) = @_; 484 my ($self, $cb) = @_;
389 485
390 $self->{on_drain} = $cb; 486 $self->{on_drain} = $cb;
391 487
392 $cb->($self) 488 $cb->($self)
393 if $cb && $self->{low_water_mark} >= length $self->{wbuf}; 489 if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf});
394} 490}
395 491
396=item $handle->push_write ($data) 492=item $handle->push_write ($data)
397 493
398Queues the given scalar to be written. You can push as much data as you 494Queues the given scalar to be written. You can push as much data as you
415 substr $self->{wbuf}, 0, $len, ""; 511 substr $self->{wbuf}, 0, $len, "";
416 512
417 $self->{_activity} = AnyEvent->now; 513 $self->{_activity} = AnyEvent->now;
418 514
419 $self->{on_drain}($self) 515 $self->{on_drain}($self)
420 if $self->{low_water_mark} >= length $self->{wbuf} 516 if $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf})
421 && $self->{on_drain}; 517 && $self->{on_drain};
422 518
423 delete $self->{_ww} unless length $self->{wbuf}; 519 delete $self->{_ww} unless length $self->{wbuf};
424 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) { 520 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
425 $self->_error ($!, 1); 521 $self->_error ($!, 1);
426 } 522 }
427 }; 523 };
428 524
429 # try to write data immediately 525 # try to write data immediately
430 $cb->(); 526 $cb->() unless $self->{autocork};
431 527
432 # if still data left in wbuf, we need to poll 528 # if still data left in wbuf, we need to poll
433 $self->{_ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb) 529 $self->{_ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb)
434 if length $self->{wbuf}; 530 if length $self->{wbuf};
435 }; 531 };
449 545
450 @_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write") 546 @_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write")
451 ->($self, @_); 547 ->($self, @_);
452 } 548 }
453 549
454 if ($self->{filter_w}) { 550 if ($self->{tls}) {
455 $self->{filter_w}($self, \$_[0]); 551 $self->{_tls_wbuf} .= $_[0];
552
553 &_dotls ($self);
456 } else { 554 } else {
457 $self->{wbuf} .= $_[0]; 555 $self->{wbuf} .= $_[0];
458 $self->_drain_wbuf; 556 $self->_drain_wbuf;
459 } 557 }
460} 558}
477=cut 575=cut
478 576
479register_write_type netstring => sub { 577register_write_type netstring => sub {
480 my ($self, $string) = @_; 578 my ($self, $string) = @_;
481 579
482 sprintf "%d:%s,", (length $string), $string 580 (length $string) . ":$string,"
581};
582
583=item packstring => $format, $data
584
585An octet string prefixed with an encoded length. The encoding C<$format>
586uses the same format as a Perl C<pack> format, but must specify a single
587integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
588optional C<!>, C<< < >> or C<< > >> modifier).
589
590=cut
591
592register_write_type packstring => sub {
593 my ($self, $format, $string) = @_;
594
595 pack "$format/a*", $string
483}; 596};
484 597
485=item json => $array_or_hashref 598=item json => $array_or_hashref
486 599
487Encodes the given hash or array reference into a JSON object. Unless you 600Encodes the given hash or array reference into a JSON object. Unless you
521 634
522 $self->{json} ? $self->{json}->encode ($ref) 635 $self->{json} ? $self->{json}->encode ($ref)
523 : JSON::encode_json ($ref) 636 : JSON::encode_json ($ref)
524}; 637};
525 638
639=item storable => $reference
640
641Freezes the given reference using L<Storable> and writes it to the
642handle. Uses the C<nfreeze> format.
643
644=cut
645
646register_write_type storable => sub {
647 my ($self, $ref) = @_;
648
649 require Storable;
650
651 pack "w/a*", Storable::nfreeze ($ref)
652};
653
526=back 654=back
527 655
528=item AnyEvent::Handle::register_write_type type => $coderef->($handle, @args) 656=item AnyEvent::Handle::register_write_type type => $coderef->($handle, @args)
529 657
530This function (not method) lets you add your own types to C<push_write>. 658This function (not method) lets you add your own types to C<push_write>.
552ways, the "simple" way, using only C<on_read> and the "complex" way, using 680ways, the "simple" way, using only C<on_read> and the "complex" way, using
553a queue. 681a queue.
554 682
555In the simple case, you just install an C<on_read> callback and whenever 683In the simple case, you just install an C<on_read> callback and whenever
556new data arrives, it will be called. You can then remove some data (if 684new data arrives, it will be called. You can then remove some data (if
557enough is there) from the read buffer (C<< $handle->rbuf >>) if you want 685enough is there) from the read buffer (C<< $handle->rbuf >>). Or you cna
558or not. 686leave the data there if you want to accumulate more (e.g. when only a
687partial message has been received so far).
559 688
560In the more complex case, you want to queue multiple callbacks. In this 689In the more complex case, you want to queue multiple callbacks. In this
561case, AnyEvent::Handle will call the first queued callback each time new 690case, AnyEvent::Handle will call the first queued callback each time new
562data arrives and removes it when it has done its job (see C<push_read>, 691data arrives (also the first time it is queued) and removes it when it has
563below). 692done its job (see C<push_read>, below).
564 693
565This way you can, for example, push three line-reads, followed by reading 694This way you can, for example, push three line-reads, followed by reading
566a chunk of data, and AnyEvent::Handle will execute them in order. 695a chunk of data, and AnyEvent::Handle will execute them in order.
567 696
568Example 1: EPP protocol parser. EPP sends 4 byte length info, followed by 697Example 1: EPP protocol parser. EPP sends 4 byte length info, followed by
581 # handle xml 710 # handle xml
582 }); 711 });
583 }); 712 });
584 }); 713 });
585 714
586Example 2: Implement a client for a protocol that replies either with 715Example 2: Implement a client for a protocol that replies either with "OK"
587"OK" and another line or "ERROR" for one request, and 64 bytes for the 716and another line or "ERROR" for the first request that is sent, and 64
588second request. Due tot he availability of a full queue, we can just 717bytes for the second request. Due to the availability of a queue, we can
589pipeline sending both requests and manipulate the queue as necessary in 718just pipeline sending both requests and manipulate the queue as necessary
590the callbacks: 719in the callbacks.
591 720
592 # request one 721When the first callback is called and sees an "OK" response, it will
722C<unshift> another line-read. This line-read will be queued I<before> the
72364-byte chunk callback.
724
725 # request one, returns either "OK + extra line" or "ERROR"
593 $handle->push_write ("request 1\015\012"); 726 $handle->push_write ("request 1\015\012");
594 727
595 # we expect "ERROR" or "OK" as response, so push a line read 728 # we expect "ERROR" or "OK" as response, so push a line read
596 $handle->push_read (line => sub { 729 $handle->push_read (line => sub {
597 # if we got an "OK", we have to _prepend_ another line, 730 # if we got an "OK", we have to _prepend_ another line,
604 ... 737 ...
605 }); 738 });
606 } 739 }
607 }); 740 });
608 741
609 # request two 742 # request two, simply returns 64 octets
610 $handle->push_write ("request 2\015\012"); 743 $handle->push_write ("request 2\015\012");
611 744
612 # simply read 64 bytes, always 745 # simply read 64 bytes, always
613 $handle->push_read (chunk => 64, sub { 746 $handle->push_read (chunk => 64, sub {
614 my $response = $_[1]; 747 my $response = $_[1];
620=cut 753=cut
621 754
622sub _drain_rbuf { 755sub _drain_rbuf {
623 my ($self) = @_; 756 my ($self) = @_;
624 757
758 local $self->{_in_drain} = 1;
759
625 if ( 760 if (
626 defined $self->{rbuf_max} 761 defined $self->{rbuf_max}
627 && $self->{rbuf_max} < length $self->{rbuf} 762 && $self->{rbuf_max} < length $self->{rbuf}
628 ) { 763 ) {
629 return $self->_error (&Errno::ENOSPC, 1); 764 $self->_error (&Errno::ENOSPC, 1), return;
630 } 765 }
631 766
632 return if $self->{in_drain}; 767 while () {
633 local $self->{in_drain} = 1; 768 # we need to use a separate tls read buffer, as we must not receive data while
769 # we are draining the buffer, and this can only happen with TLS.
770 $self->{rbuf} .= delete $self->{_tls_rbuf} if exists $self->{_tls_rbuf};
634 771
635 while (my $len = length $self->{rbuf}) { 772 my $len = length $self->{rbuf};
636 no strict 'refs'; 773
637 if (my $cb = shift @{ $self->{_queue} }) { 774 if (my $cb = shift @{ $self->{_queue} }) {
638 unless ($cb->($self)) { 775 unless ($cb->($self)) {
639 if ($self->{_eof}) { 776 if ($self->{_eof}) {
640 # 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)
641 return $self->_error (&Errno::EPIPE, 1); 778 $self->_error (&Errno::EPIPE, 1), return;
642 } 779 }
643 780
644 unshift @{ $self->{_queue} }, $cb; 781 unshift @{ $self->{_queue} }, $cb;
645 last; 782 last;
646 } 783 }
647 } elsif ($self->{on_read}) { 784 } elsif ($self->{on_read}) {
785 last unless $len;
786
648 $self->{on_read}($self); 787 $self->{on_read}($self);
649 788
650 if ( 789 if (
651 $len == length $self->{rbuf} # if no data has been consumed 790 $len == length $self->{rbuf} # if no data has been consumed
652 && !@{ $self->{_queue} } # and the queue is still empty 791 && !@{ $self->{_queue} } # and the queue is still empty
653 && $self->{on_read} # but we still have on_read 792 && $self->{on_read} # but we still have on_read
654 ) { 793 ) {
655 # no further data will arrive 794 # no further data will arrive
656 # so no progress can be made 795 # so no progress can be made
657 return $self->_error (&Errno::EPIPE, 1) 796 $self->_error (&Errno::EPIPE, 1), return
658 if $self->{_eof}; 797 if $self->{_eof};
659 798
660 last; # more data might arrive 799 last; # more data might arrive
661 } 800 }
662 } else { 801 } else {
663 # read side becomes idle 802 # read side becomes idle
664 delete $self->{_rw}; 803 delete $self->{_rw} unless $self->{tls};
665 last; 804 last;
666 } 805 }
667 } 806 }
668 807
808 if ($self->{_eof}) {
809 if ($self->{on_eof}) {
669 $self->{on_eof}($self) 810 $self->{on_eof}($self)
670 if $self->{_eof} && $self->{on_eof}; 811 } else {
812 $self->_error (0, 1);
813 }
814 }
671 815
672 # may need to restart read watcher 816 # may need to restart read watcher
673 unless ($self->{_rw}) { 817 unless ($self->{_rw}) {
674 $self->start_read 818 $self->start_read
675 if $self->{on_read} || @{ $self->{_queue} }; 819 if $self->{on_read} || @{ $self->{_queue} };
686 830
687sub on_read { 831sub on_read {
688 my ($self, $cb) = @_; 832 my ($self, $cb) = @_;
689 833
690 $self->{on_read} = $cb; 834 $self->{on_read} = $cb;
835 $self->_drain_rbuf if $cb && !$self->{_in_drain};
691} 836}
692 837
693=item $handle->rbuf 838=item $handle->rbuf
694 839
695Returns the read buffer (as a modifiable lvalue). 840Returns the read buffer (as a modifiable lvalue).
696 841
697You can access the read buffer directly as the C<< ->{rbuf} >> member, if 842You can access the read buffer directly as the C<< ->{rbuf} >>
698you want. 843member, if you want. However, the only operation allowed on the
844read buffer (apart from looking at it) is removing data from its
845beginning. Otherwise modifying or appending to it is not allowed and will
846lead to hard-to-track-down bugs.
699 847
700NOTE: The read buffer should only be used or modified if the C<on_read>, 848NOTE: The read buffer should only be used or modified if the C<on_read>,
701C<push_read> or C<unshift_read> methods are used. The other read methods 849C<push_read> or C<unshift_read> methods are used. The other read methods
702automatically manage the read buffer. 850automatically manage the read buffer.
703 851
744 $cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_read") 892 $cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_read")
745 ->($self, $cb, @_); 893 ->($self, $cb, @_);
746 } 894 }
747 895
748 push @{ $self->{_queue} }, $cb; 896 push @{ $self->{_queue} }, $cb;
749 $self->_drain_rbuf; 897 $self->_drain_rbuf unless $self->{_in_drain};
750} 898}
751 899
752sub unshift_read { 900sub unshift_read {
753 my $self = shift; 901 my $self = shift;
754 my $cb = pop; 902 my $cb = pop;
760 ->($self, $cb, @_); 908 ->($self, $cb, @_);
761 } 909 }
762 910
763 911
764 unshift @{ $self->{_queue} }, $cb; 912 unshift @{ $self->{_queue} }, $cb;
765 $self->_drain_rbuf; 913 $self->_drain_rbuf unless $self->{_in_drain};
766} 914}
767 915
768=item $handle->push_read (type => @args, $cb) 916=item $handle->push_read (type => @args, $cb)
769 917
770=item $handle->unshift_read (type => @args, $cb) 918=item $handle->unshift_read (type => @args, $cb)
800 $cb->($_[0], substr $_[0]{rbuf}, 0, $len, ""); 948 $cb->($_[0], substr $_[0]{rbuf}, 0, $len, "");
801 1 949 1
802 } 950 }
803}; 951};
804 952
805# compatibility with older API
806sub push_read_chunk {
807 $_[0]->push_read (chunk => $_[1], $_[2]);
808}
809
810sub unshift_read_chunk {
811 $_[0]->unshift_read (chunk => $_[1], $_[2]);
812}
813
814=item line => [$eol, ]$cb->($handle, $line, $eol) 953=item line => [$eol, ]$cb->($handle, $line, $eol)
815 954
816The callback will be called only once a full line (including the end of 955The callback will be called only once a full line (including the end of
817line marker, C<$eol>) has been read. This line (excluding the end of line 956line marker, C<$eol>) has been read. This line (excluding the end of line
818marker) will be passed to the callback as second argument (C<$line>), and 957marker) will be passed to the callback as second argument (C<$line>), and
833=cut 972=cut
834 973
835register_read_type line => sub { 974register_read_type line => sub {
836 my ($self, $cb, $eol) = @_; 975 my ($self, $cb, $eol) = @_;
837 976
838 $eol = qr|(\015?\012)| if @_ < 3; 977 if (@_ < 3) {
839 $eol = quotemeta $eol unless ref $eol; 978 # this is more than twice as fast as the generic code below
840 $eol = qr|^(.*?)($eol)|s;
841
842 sub { 979 sub {
843 $_[0]{rbuf} =~ s/$eol// or return; 980 $_[0]{rbuf} =~ s/^([^\015\012]*)(\015?\012)// or return;
844 981
845 $cb->($_[0], $1, $2); 982 $cb->($_[0], $1, $2);
846 1
847 }
848};
849
850# compatibility with older API
851sub push_read_line {
852 my $self = shift;
853 $self->push_read (line => @_);
854}
855
856sub unshift_read_line {
857 my $self = shift;
858 $self->unshift_read (line => @_);
859}
860
861=item netstring => $cb->($handle, $string)
862
863A netstring (http://cr.yp.to/proto/netstrings.txt, this is not an endorsement).
864
865Throws an error with C<$!> set to EBADMSG on format violations.
866
867=cut
868
869register_read_type netstring => sub {
870 my ($self, $cb) = @_;
871
872 sub {
873 unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
874 if ($_[0]{rbuf} =~ /[^0-9]/) {
875 $self->_error (&Errno::EBADMSG);
876 } 983 1
877 return;
878 } 984 }
985 } else {
986 $eol = quotemeta $eol unless ref $eol;
987 $eol = qr|^(.*?)($eol)|s;
879 988
880 my $len = $1; 989 sub {
990 $_[0]{rbuf} =~ s/$eol// or return;
881 991
882 $self->unshift_read (chunk => $len, sub { 992 $cb->($_[0], $1, $2);
883 my $string = $_[1];
884 $_[0]->unshift_read (chunk => 1, sub {
885 if ($_[1] eq ",") {
886 $cb->($_[0], $string);
887 } else {
888 $self->_error (&Errno::EBADMSG);
889 }
890 }); 993 1
891 }); 994 }
892
893 1
894 } 995 }
895}; 996};
896 997
897=item regex => $accept[, $reject[, $skip], $cb->($handle, $data) 998=item regex => $accept[, $reject[, $skip], $cb->($handle, $data)
898 999
962 1063
963 () 1064 ()
964 } 1065 }
965}; 1066};
966 1067
1068=item netstring => $cb->($handle, $string)
1069
1070A netstring (http://cr.yp.to/proto/netstrings.txt, this is not an endorsement).
1071
1072Throws an error with C<$!> set to EBADMSG on format violations.
1073
1074=cut
1075
1076register_read_type netstring => sub {
1077 my ($self, $cb) = @_;
1078
1079 sub {
1080 unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
1081 if ($_[0]{rbuf} =~ /[^0-9]/) {
1082 $self->_error (&Errno::EBADMSG);
1083 }
1084 return;
1085 }
1086
1087 my $len = $1;
1088
1089 $self->unshift_read (chunk => $len, sub {
1090 my $string = $_[1];
1091 $_[0]->unshift_read (chunk => 1, sub {
1092 if ($_[1] eq ",") {
1093 $cb->($_[0], $string);
1094 } else {
1095 $self->_error (&Errno::EBADMSG);
1096 }
1097 });
1098 });
1099
1100 1
1101 }
1102};
1103
1104=item packstring => $format, $cb->($handle, $string)
1105
1106An octet string prefixed with an encoded length. The encoding C<$format>
1107uses the same format as a Perl C<pack> format, but must specify a single
1108integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
1109optional C<!>, C<< < >> or C<< > >> modifier).
1110
1111For example, DNS over TCP uses a prefix of C<n> (2 octet network order),
1112EPP uses a prefix of C<N> (4 octtes).
1113
1114Example: read a block of data prefixed by its length in BER-encoded
1115format (very efficient).
1116
1117 $handle->push_read (packstring => "w", sub {
1118 my ($handle, $data) = @_;
1119 });
1120
1121=cut
1122
1123register_read_type packstring => sub {
1124 my ($self, $cb, $format) = @_;
1125
1126 sub {
1127 # when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
1128 defined (my $len = eval { unpack $format, $_[0]{rbuf} })
1129 or return;
1130
1131 $format = length pack $format, $len;
1132
1133 # bypass unshift if we already have the remaining chunk
1134 if ($format + $len <= length $_[0]{rbuf}) {
1135 my $data = substr $_[0]{rbuf}, $format, $len;
1136 substr $_[0]{rbuf}, 0, $format + $len, "";
1137 $cb->($_[0], $data);
1138 } else {
1139 # remove prefix
1140 substr $_[0]{rbuf}, 0, $format, "";
1141
1142 # read remaining chunk
1143 $_[0]->unshift_read (chunk => $len, $cb);
1144 }
1145
1146 1
1147 }
1148};
1149
967=item json => $cb->($handle, $hash_or_arrayref) 1150=item json => $cb->($handle, $hash_or_arrayref)
968 1151
969Reads a JSON object or array, decodes it and passes it to the callback. 1152Reads a JSON object or array, decodes it and passes it to the
1153callback. When a parse error occurs, an C<EBADMSG> error will be raised.
970 1154
971If a C<json> object was passed to the constructor, then that will be used 1155If a C<json> object was passed to the constructor, then that will be used
972for the final decode, otherwise it will create a JSON coder expecting UTF-8. 1156for the final decode, otherwise it will create a JSON coder expecting UTF-8.
973 1157
974This read type uses the incremental parser available with JSON version 1158This read type uses the incremental parser available with JSON version
981the C<json> write type description, above, for an actual example. 1165the C<json> write type description, above, for an actual example.
982 1166
983=cut 1167=cut
984 1168
985register_read_type json => sub { 1169register_read_type json => sub {
986 my ($self, $cb, $accept, $reject, $skip) = @_; 1170 my ($self, $cb) = @_;
987 1171
988 require JSON; 1172 require JSON;
989 1173
990 my $data; 1174 my $data;
991 my $rbuf = \$self->{rbuf}; 1175 my $rbuf = \$self->{rbuf};
992 1176
993 my $json = $self->{json} ||= JSON->new->utf8; 1177 my $json = $self->{json} ||= JSON->new->utf8;
994 1178
995 sub { 1179 sub {
996 my $ref = $json->incr_parse ($self->{rbuf}); 1180 my $ref = eval { $json->incr_parse ($self->{rbuf}) };
997 1181
998 if ($ref) { 1182 if ($ref) {
999 $self->{rbuf} = $json->incr_text; 1183 $self->{rbuf} = $json->incr_text;
1000 $json->incr_text = ""; 1184 $json->incr_text = "";
1001 $cb->($self, $ref); 1185 $cb->($self, $ref);
1002 1186
1003 1 1187 1
1188 } elsif ($@) {
1189 # error case
1190 $json->incr_skip;
1191
1192 $self->{rbuf} = $json->incr_text;
1193 $json->incr_text = "";
1194
1195 $self->_error (&Errno::EBADMSG);
1196
1197 ()
1004 } else { 1198 } else {
1005 $self->{rbuf} = ""; 1199 $self->{rbuf} = "";
1200
1006 () 1201 ()
1007 } 1202 }
1203 }
1204};
1205
1206=item storable => $cb->($handle, $ref)
1207
1208Deserialises a L<Storable> frozen representation as written by the
1209C<storable> write type (BER-encoded length prefix followed by nfreeze'd
1210data).
1211
1212Raises C<EBADMSG> error if the data could not be decoded.
1213
1214=cut
1215
1216register_read_type storable => sub {
1217 my ($self, $cb) = @_;
1218
1219 require Storable;
1220
1221 sub {
1222 # when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
1223 defined (my $len = eval { unpack "w", $_[0]{rbuf} })
1224 or return;
1225
1226 my $format = length pack "w", $len;
1227
1228 # bypass unshift if we already have the remaining chunk
1229 if ($format + $len <= length $_[0]{rbuf}) {
1230 my $data = substr $_[0]{rbuf}, $format, $len;
1231 substr $_[0]{rbuf}, 0, $format + $len, "";
1232 $cb->($_[0], Storable::thaw ($data));
1233 } else {
1234 # remove prefix
1235 substr $_[0]{rbuf}, 0, $format, "";
1236
1237 # read remaining chunk
1238 $_[0]->unshift_read (chunk => $len, sub {
1239 if (my $ref = eval { Storable::thaw ($_[1]) }) {
1240 $cb->($_[0], $ref);
1241 } else {
1242 $self->_error (&Errno::EBADMSG);
1243 }
1244 });
1245 }
1246
1247 1
1008 } 1248 }
1009}; 1249};
1010 1250
1011=back 1251=back
1012 1252
1033=item $handle->stop_read 1273=item $handle->stop_read
1034 1274
1035=item $handle->start_read 1275=item $handle->start_read
1036 1276
1037In rare cases you actually do not want to read anything from the 1277In rare cases you actually do not want to read anything from the
1038socket. In this case you can call C<stop_read>. Neither C<on_read> no 1278socket. In this case you can call C<stop_read>. Neither C<on_read> nor
1039any queued callbacks will be executed then. To start reading again, call 1279any queued callbacks will be executed then. To start reading again, call
1040C<start_read>. 1280C<start_read>.
1041 1281
1042Note that AnyEvent::Handle will automatically C<start_read> for you when 1282Note that AnyEvent::Handle will automatically C<start_read> for you when
1043you change the C<on_read> callback or push/unshift a read callback, and it 1283you change the C<on_read> callback or push/unshift a read callback, and it
1044will automatically C<stop_read> for you when neither C<on_read> is set nor 1284will automatically C<stop_read> for you when neither C<on_read> is set nor
1045there are any read requests in the queue. 1285there are any read requests in the queue.
1046 1286
1287These methods will have no effect when in TLS mode (as TLS doesn't support
1288half-duplex connections).
1289
1047=cut 1290=cut
1048 1291
1049sub stop_read { 1292sub stop_read {
1050 my ($self) = @_; 1293 my ($self) = @_;
1051 1294
1052 delete $self->{_rw}; 1295 delete $self->{_rw} unless $self->{tls};
1053} 1296}
1054 1297
1055sub start_read { 1298sub start_read {
1056 my ($self) = @_; 1299 my ($self) = @_;
1057 1300
1058 unless ($self->{_rw} || $self->{_eof}) { 1301 unless ($self->{_rw} || $self->{_eof}) {
1059 Scalar::Util::weaken $self; 1302 Scalar::Util::weaken $self;
1060 1303
1061 $self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub { 1304 $self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub {
1062 my $rbuf = $self->{filter_r} ? \my $buf : \$self->{rbuf}; 1305 my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf});
1063 my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf; 1306 my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf;
1064 1307
1065 if ($len > 0) { 1308 if ($len > 0) {
1066 $self->{_activity} = AnyEvent->now; 1309 $self->{_activity} = AnyEvent->now;
1067 1310
1068 $self->{filter_r} 1311 if ($self->{tls}) {
1069 ? $self->{filter_r}($self, $rbuf) 1312 Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf);
1070 : $self->_drain_rbuf; 1313
1314 &_dotls ($self);
1315 } else {
1316 $self->_drain_rbuf unless $self->{_in_drain};
1317 }
1071 1318
1072 } elsif (defined $len) { 1319 } elsif (defined $len) {
1073 delete $self->{_rw}; 1320 delete $self->{_rw};
1074 $self->{_eof} = 1; 1321 $self->{_eof} = 1;
1075 $self->_drain_rbuf; 1322 $self->_drain_rbuf unless $self->{_in_drain};
1076 1323
1077 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) { 1324 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
1078 return $self->_error ($!, 1); 1325 return $self->_error ($!, 1);
1079 } 1326 }
1080 }); 1327 });
1081 } 1328 }
1082} 1329}
1083 1330
1331# poll the write BIO and send the data if applicable
1084sub _dotls { 1332sub _dotls {
1085 my ($self) = @_; 1333 my ($self) = @_;
1086 1334
1087 my $buf; 1335 my $tmp;
1088 1336
1089 if (length $self->{_tls_wbuf}) { 1337 if (length $self->{_tls_wbuf}) {
1090 while ((my $len = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) { 1338 while (($tmp = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) {
1091 substr $self->{_tls_wbuf}, 0, $len, ""; 1339 substr $self->{_tls_wbuf}, 0, $tmp, "";
1092 } 1340 }
1093 } 1341 }
1094 1342
1095 if (length ($buf = Net::SSLeay::BIO_read ($self->{_wbio}))) {
1096 $self->{wbuf} .= $buf;
1097 $self->_drain_wbuf;
1098 }
1099
1100 while (defined ($buf = Net::SSLeay::read ($self->{tls}))) { 1343 while (defined ($tmp = Net::SSLeay::read ($self->{tls}))) {
1101 if (length $buf) { 1344 unless (length $tmp) {
1102 $self->{rbuf} .= $buf;
1103 $self->_drain_rbuf;
1104 } else {
1105 # let's treat SSL-eof as we treat normal EOF 1345 # let's treat SSL-eof as we treat normal EOF
1346 delete $self->{_rw};
1106 $self->{_eof} = 1; 1347 $self->{_eof} = 1;
1107 $self->_shutdown; 1348 &_freetls;
1108 return;
1109 } 1349 }
1110 }
1111 1350
1351 $self->{_tls_rbuf} .= $tmp;
1352 $self->_drain_rbuf unless $self->{_in_drain};
1353 $self->{tls} or return; # tls session might have gone away in callback
1354 }
1355
1112 my $err = Net::SSLeay::get_error ($self->{tls}, -1); 1356 $tmp = Net::SSLeay::get_error ($self->{tls}, -1);
1113 1357
1114 if ($err!= Net::SSLeay::ERROR_WANT_READ ()) { 1358 if ($tmp != Net::SSLeay::ERROR_WANT_READ ()) {
1115 if ($err == Net::SSLeay::ERROR_SYSCALL ()) { 1359 if ($tmp == Net::SSLeay::ERROR_SYSCALL ()) {
1116 return $self->_error ($!, 1); 1360 return $self->_error ($!, 1);
1117 } elsif ($err == Net::SSLeay::ERROR_SSL ()) { 1361 } elsif ($tmp == Net::SSLeay::ERROR_SSL ()) {
1118 return $self->_error (&Errno::EIO, 1); 1362 return $self->_error (&Errno::EIO, 1);
1119 } 1363 }
1120 1364
1121 # all others are fine for our purposes 1365 # all other errors are fine for our purposes
1366 }
1367
1368 while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) {
1369 $self->{wbuf} .= $tmp;
1370 $self->_drain_wbuf;
1122 } 1371 }
1123} 1372}
1124 1373
1125=item $handle->starttls ($tls[, $tls_ctx]) 1374=item $handle->starttls ($tls[, $tls_ctx])
1126 1375
1136 1385
1137The TLS connection object will end up in C<< $handle->{tls} >> after this 1386The TLS connection object will end up in C<< $handle->{tls} >> after this
1138call and can be used or changed to your liking. Note that the handshake 1387call and can be used or changed to your liking. Note that the handshake
1139might have already started when this function returns. 1388might have already started when this function returns.
1140 1389
1390If it an error to start a TLS handshake more than once per
1391AnyEvent::Handle object (this is due to bugs in OpenSSL).
1392
1141=cut 1393=cut
1142 1394
1143sub starttls { 1395sub starttls {
1144 my ($self, $ssl, $ctx) = @_; 1396 my ($self, $ssl, $ctx) = @_;
1145 1397
1146 $self->stoptls; 1398 require Net::SSLeay;
1147 1399
1400 Carp::croak "it is an error to call starttls more than once on an AnyEvent::Handle object"
1401 if $self->{tls};
1402
1148 if ($ssl eq "accept") { 1403 if ($ssl eq "accept") {
1149 $ssl = Net::SSLeay::new ($ctx || TLS_CTX ()); 1404 $ssl = Net::SSLeay::new ($ctx || TLS_CTX ());
1150 Net::SSLeay::set_accept_state ($ssl); 1405 Net::SSLeay::set_accept_state ($ssl);
1151 } elsif ($ssl eq "connect") { 1406 } elsif ($ssl eq "connect") {
1152 $ssl = Net::SSLeay::new ($ctx || TLS_CTX ()); 1407 $ssl = Net::SSLeay::new ($ctx || TLS_CTX ());
1158 # basically, this is deep magic (because SSL_read should have the same issues) 1413 # basically, this is deep magic (because SSL_read should have the same issues)
1159 # but the openssl maintainers basically said: "trust us, it just works". 1414 # but the openssl maintainers basically said: "trust us, it just works".
1160 # (unfortunately, we have to hardcode constants because the abysmally misdesigned 1415 # (unfortunately, we have to hardcode constants because the abysmally misdesigned
1161 # and mismaintained ssleay-module doesn't even offer them). 1416 # and mismaintained ssleay-module doesn't even offer them).
1162 # http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html 1417 # http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html
1418 #
1419 # in short: this is a mess.
1420 #
1421 # note that we do not try to keep the length constant between writes as we are required to do.
1422 # we assume that most (but not all) of this insanity only applies to non-blocking cases,
1423 # and we drive openssl fully in blocking mode here. Or maybe we don't - openssl seems to
1424 # have identity issues in that area.
1163 Net::SSLeay::CTX_set_mode ($self->{tls}, 1425 Net::SSLeay::CTX_set_mode ($self->{tls},
1164 (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1) 1426 (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)
1165 | (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2)); 1427 | (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2));
1166 1428
1167 $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); 1429 $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1168 $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); 1430 $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1169 1431
1170 Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio}); 1432 Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio});
1171 1433
1172 $self->{filter_w} = sub { 1434 &_dotls; # need to trigger the initial handshake
1173 $_[0]{_tls_wbuf} .= ${$_[1]}; 1435 $self->start_read; # make sure we actually do read
1174 &_dotls;
1175 };
1176 $self->{filter_r} = sub {
1177 Net::SSLeay::BIO_write ($_[0]{_rbio}, ${$_[1]});
1178 &_dotls;
1179 };
1180} 1436}
1181 1437
1182=item $handle->stoptls 1438=item $handle->stoptls
1183 1439
1184Destroys the SSL connection, if any. Partial read or write data will be 1440Shuts down the SSL connection - this makes a proper EOF handshake by
1185lost. 1441sending a close notify to the other side, but since OpenSSL doesn't
1442support non-blocking shut downs, it is not possible to re-use the stream
1443afterwards.
1186 1444
1187=cut 1445=cut
1188 1446
1189sub stoptls { 1447sub stoptls {
1190 my ($self) = @_; 1448 my ($self) = @_;
1191 1449
1450 if ($self->{tls}) {
1451 Net::SSLeay::shutdown ($self->{tls});
1452
1453 &_dotls;
1454
1455 # we don't give a shit. no, we do, but we can't. no...
1456 # we, we... have to use openssl :/
1457 &_freetls;
1458 }
1459}
1460
1461sub _freetls {
1462 my ($self) = @_;
1463
1464 return unless $self->{tls};
1465
1192 Net::SSLeay::free (delete $self->{tls}) if $self->{tls}; 1466 Net::SSLeay::free (delete $self->{tls});
1193 1467
1194 delete $self->{_rbio}; 1468 delete @$self{qw(_rbio _wbio _tls_wbuf)};
1195 delete $self->{_wbio};
1196 delete $self->{_tls_wbuf};
1197 delete $self->{filter_r};
1198 delete $self->{filter_w};
1199} 1469}
1200 1470
1201sub DESTROY { 1471sub DESTROY {
1202 my $self = shift; 1472 my ($self) = @_;
1203 1473
1204 $self->stoptls; 1474 &_freetls;
1475
1476 my $linger = exists $self->{linger} ? $self->{linger} : 3600;
1477
1478 if ($linger && length $self->{wbuf}) {
1479 my $fh = delete $self->{fh};
1480 my $wbuf = delete $self->{wbuf};
1481
1482 my @linger;
1483
1484 push @linger, AnyEvent->io (fh => $fh, poll => "w", cb => sub {
1485 my $len = syswrite $fh, $wbuf, length $wbuf;
1486
1487 if ($len > 0) {
1488 substr $wbuf, 0, $len, "";
1489 } else {
1490 @linger = (); # end
1491 }
1492 });
1493 push @linger, AnyEvent->timer (after => $linger, cb => sub {
1494 @linger = ();
1495 });
1496 }
1497}
1498
1499=item $handle->destroy
1500
1501Shuts down the handle object as much as possible - this call ensures that
1502no further callbacks will be invoked and resources will be freed as much
1503as possible. You must not call any methods on the object afterwards.
1504
1505Normally, you can just "forget" any references to an AnyEvent::Handle
1506object and it will simply shut down. This works in fatal error and EOF
1507callbacks, as well as code outside. It does I<NOT> work in a read or write
1508callback, so when you want to destroy the AnyEvent::Handle object from
1509within such an callback. You I<MUST> call C<< ->destroy >> explicitly in
1510that case.
1511
1512The handle might still linger in the background and write out remaining
1513data, as specified by the C<linger> option, however.
1514
1515=cut
1516
1517sub destroy {
1518 my ($self) = @_;
1519
1520 $self->DESTROY;
1521 %$self = ();
1205} 1522}
1206 1523
1207=item AnyEvent::Handle::TLS_CTX 1524=item AnyEvent::Handle::TLS_CTX
1208 1525
1209This function creates and returns the Net::SSLeay::CTX object used by 1526This function creates and returns the Net::SSLeay::CTX object used by
1239 } 1556 }
1240} 1557}
1241 1558
1242=back 1559=back
1243 1560
1561
1562=head1 NONFREQUENTLY ASKED QUESTIONS
1563
1564=over 4
1565
1566=item I C<undef> the AnyEvent::Handle reference inside my callback and
1567still get further invocations!
1568
1569That's because AnyEvent::Handle keeps a reference to itself when handling
1570read or write callbacks.
1571
1572It is only safe to "forget" the reference inside EOF or error callbacks,
1573from within all other callbacks, you need to explicitly call the C<<
1574->destroy >> method.
1575
1576=item I get different callback invocations in TLS mode/Why can't I pause
1577reading?
1578
1579Unlike, say, TCP, TLS connections do not consist of two independent
1580communication channels, one for each direction. Or put differently. The
1581read and write directions are not independent of each other: you cannot
1582write data unless you are also prepared to read, and vice versa.
1583
1584This can mean than, in TLS mode, you might get C<on_error> or C<on_eof>
1585callback invocations when you are not expecting any read data - the reason
1586is that AnyEvent::Handle always reads in TLS mode.
1587
1588During the connection, you have to make sure that you always have a
1589non-empty read-queue, or an C<on_read> watcher. At the end of the
1590connection (or when you no longer want to use it) you can call the
1591C<destroy> method.
1592
1593=item How do I read data until the other side closes the connection?
1594
1595If you just want to read your data into a perl scalar, the easiest way
1596to achieve this is by setting an C<on_read> callback that does nothing,
1597clearing the C<on_eof> callback and in the C<on_error> callback, the data
1598will be in C<$_[0]{rbuf}>:
1599
1600 $handle->on_read (sub { });
1601 $handle->on_eof (undef);
1602 $handle->on_error (sub {
1603 my $data = delete $_[0]{rbuf};
1604 undef $handle;
1605 });
1606
1607The reason to use C<on_error> is that TCP connections, due to latencies
1608and packets loss, might get closed quite violently with an error, when in
1609fact, all data has been received.
1610
1611It is usually better to use acknowledgements when transferring data,
1612to make sure the other side hasn't just died and you got the data
1613intact. This is also one reason why so many internet protocols have an
1614explicit QUIT command.
1615
1616=item I don't want to destroy the handle too early - how do I wait until
1617all data has been written?
1618
1619After writing your last bits of data, set the C<on_drain> callback
1620and destroy the handle in there - with the default setting of
1621C<low_water_mark> this will be called precisely when all data has been
1622written to the socket:
1623
1624 $handle->push_write (...);
1625 $handle->on_drain (sub {
1626 warn "all data submitted to the kernel\n";
1627 undef $handle;
1628 });
1629
1630=back
1631
1632
1244=head1 SUBCLASSING AnyEvent::Handle 1633=head1 SUBCLASSING AnyEvent::Handle
1245 1634
1246In many cases, you might want to subclass AnyEvent::Handle. 1635In many cases, you might want to subclass AnyEvent::Handle.
1247 1636
1248To make this easier, a given version of AnyEvent::Handle uses these 1637To make this easier, a given version of AnyEvent::Handle uses these
1251=over 4 1640=over 4
1252 1641
1253=item * all constructor arguments become object members. 1642=item * all constructor arguments become object members.
1254 1643
1255At least initially, when you pass a C<tls>-argument to the constructor it 1644At least initially, when you pass a C<tls>-argument to the constructor it
1256will end up in C<< $handle->{tls} >>. Those members might be changes or 1645will end up in C<< $handle->{tls} >>. Those members might be changed or
1257mutated later on (for example C<tls> will hold the TLS connection object). 1646mutated later on (for example C<tls> will hold the TLS connection object).
1258 1647
1259=item * other object member names are prefixed with an C<_>. 1648=item * other object member names are prefixed with an C<_>.
1260 1649
1261All object members not explicitly documented (internal use) are prefixed 1650All object members not explicitly documented (internal use) are prefixed

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