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Comparing AnyEvent/lib/AnyEvent/Handle.pm (file contents):
Revision 1.83 by root, Thu Aug 21 19:11:37 2008 UTC vs.
Revision 1.107 by root, Wed Nov 26 06:40:47 2008 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 = 4.33;
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
81Set 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,
82i.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
83connection cleanly. 86connection cleanly.
84 87
85For 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,
86you 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
87callback 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
88down. 91down.
89 92
90While 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,
91otherwise 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
92waiting for data. 95waiting for data.
93 96
94If 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
95set, then a fatal error will be raised with C<$!> set to <0>. 98set, then a fatal error will be raised with C<$!> set to <0>.
100occured, such as not being able to resolve the hostname, failure to 103occured, such as not being able to resolve the hostname, failure to
101connect or a read error. 104connect or a read error.
102 105
103Some errors are fatal (which is indicated by C<$fatal> being true). On 106Some errors are fatal (which is indicated by C<$fatal> being true). On
104fatal 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
105(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
106errors are an EOF condition with active (but unsatisifable) read watchers 109errors are an EOF condition with active (but unsatisifable) read watchers
107(C<EPIPE>) or I/O errors. 110(C<EPIPE>) or I/O errors.
108 111
109Non-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
110to simply ignore this parameter and instead abondon the handle object 113to simply ignore this parameter and instead abondon the handle object
149=item timeout => $fractional_seconds 152=item timeout => $fractional_seconds
150 153
151If non-zero, then this enables an "inactivity" timeout: whenever this many 154If non-zero, then this enables an "inactivity" timeout: whenever this many
152seconds pass without a successful read or write on the underlying file 155seconds pass without a successful read or write on the underlying file
153handle, the C<on_timeout> callback will be invoked (and if that one is 156handle, the C<on_timeout> callback will be invoked (and if that one is
154missing, an C<ETIMEDOUT> error will be raised). 157missing, a non-fatal C<ETIMEDOUT> error will be raised).
155 158
156Note that timeout processing is also active when you currently do not have 159Note that timeout processing is also active when you currently do not have
157any outstanding read or write requests: If you plan to keep the connection 160any outstanding read or write requests: If you plan to keep the connection
158idle then you should disable the timout temporarily or ignore the timeout 161idle then you should disable the timout temporarily or ignore the timeout
159in the C<on_timeout> callback. 162in the C<on_timeout> callback, in which case AnyEvent::Handle will simply
163restart the timeout.
160 164
161Zero (the default) disables this timeout. 165Zero (the default) disables this timeout.
162 166
163=item on_timeout => $cb->($handle) 167=item on_timeout => $cb->($handle)
164 168
168 172
169=item rbuf_max => <bytes> 173=item rbuf_max => <bytes>
170 174
171If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>) 175If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)
172when the read buffer ever (strictly) exceeds this size. This is useful to 176when the read buffer ever (strictly) exceeds this size. This is useful to
173avoid denial-of-service attacks. 177avoid some forms of denial-of-service attacks.
174 178
175For example, a server accepting connections from untrusted sources should 179For example, a server accepting connections from untrusted sources should
176be configured to accept only so-and-so much data that it cannot act on 180be configured to accept only so-and-so much data that it cannot act on
177(for example, when expecting a line, an attacker could send an unlimited 181(for example, when expecting a line, an attacker could send an unlimited
178amount of data without a callback ever being called as long as the line 182amount of data without a callback ever being called as long as the line
179isn't finished). 183isn't finished).
180 184
181=item autocork => <boolean> 185=item autocork => <boolean>
182 186
183When disabled (the default), then C<push_write> will try to immediately 187When disabled (the default), then C<push_write> will try to immediately
184write the data to the handle if possible. This avoids having to register 188write the data to the handle, if possible. This avoids having to register
185a write watcher and wait for the next event loop iteration, but can be 189a write watcher and wait for the next event loop iteration, but can
186inefficient if you write multiple small chunks (this disadvantage is 190be inefficient if you write multiple small chunks (on the wire, this
187usually avoided by your kernel's nagle algorithm, see C<low_delay>). 191disadvantage is usually avoided by your kernel's nagle algorithm, see
192C<no_delay>, but this option can save costly syscalls).
188 193
189When enabled, then writes will always be queued till the next event loop 194When enabled, then writes will always be queued till the next event loop
190iteration. This is efficient when you do many small writes per iteration, 195iteration. This is efficient when you do many small writes per iteration,
191but less efficient when you do a single write only. 196but less efficient when you do a single write only per iteration (or when
197the write buffer often is full). It also increases write latency.
192 198
193=item no_delay => <boolean> 199=item no_delay => <boolean>
194 200
195When doing small writes on sockets, your operating system kernel might 201When doing small writes on sockets, your operating system kernel might
196wait a bit for more data before actually sending it out. This is called 202wait a bit for more data before actually sending it out. This is called
197the Nagle algorithm, and usually it is beneficial. 203the Nagle algorithm, and usually it is beneficial.
198 204
199In some situations you want as low a delay as possible, which cna be 205In some situations you want as low a delay as possible, which can be
200accomplishd by setting this option to true. 206accomplishd by setting this option to a true value.
201 207
202The default is your opertaing system's default behaviour, this option 208The default is your opertaing system's default behaviour (most likely
203explicitly enables or disables it, if possible. 209enabled), this option explicitly enables or disables it, if possible.
204 210
205=item read_size => <bytes> 211=item read_size => <bytes>
206 212
207The default read block size (the amount of bytes this module will try to read 213The default read block size (the amount of bytes this module will
208during each (loop iteration). Default: C<8192>. 214try to read during each loop iteration, which affects memory
215requirements). Default: C<8192>.
209 216
210=item low_water_mark => <bytes> 217=item low_water_mark => <bytes>
211 218
212Sets the amount of bytes (default: C<0>) that make up an "empty" write 219Sets the amount of bytes (default: C<0>) that make up an "empty" write
213buffer: If the write reaches this size or gets even samller it is 220buffer: If the write reaches this size or gets even samller it is
214considered empty. 221considered empty.
215 222
223Sometimes it can be beneficial (for performance reasons) to add data to
224the write buffer before it is fully drained, but this is a rare case, as
225the operating system kernel usually buffers data as well, so the default
226is good in almost all cases.
227
216=item linger => <seconds> 228=item linger => <seconds>
217 229
218If non-zero (default: C<3600>), then the destructor of the 230If non-zero (default: C<3600>), then the destructor of the
219AnyEvent::Handle object will check wether there is still outstanding write 231AnyEvent::Handle object will check whether there is still outstanding
220data and will install a watcher that will write out this data. No errors 232write data and will install a watcher that will write this data to the
221will be reported (this mostly matches how the operating system treats 233socket. No errors will be reported (this mostly matches how the operating
222outstanding data at socket close time). 234system treats outstanding data at socket close time).
223 235
224This will not work for partial TLS data that could not yet been 236This will not work for partial TLS data that could not be encoded
225encoded. This data will be lost. 237yet. This data will be lost. Calling the C<stoptls> method in time might
238help.
226 239
227=item tls => "accept" | "connect" | Net::SSLeay::SSL object 240=item tls => "accept" | "connect" | Net::SSLeay::SSL object
228 241
229When this parameter is given, it enables TLS (SSL) mode, that means it 242When this parameter is given, it enables TLS (SSL) mode, that means
230will start making tls handshake and will transparently encrypt/decrypt 243AnyEvent will start a TLS handshake as soon as the conenction has been
231data. 244established and will transparently encrypt/decrypt data afterwards.
232 245
233TLS mode requires Net::SSLeay to be installed (it will be loaded 246TLS mode requires Net::SSLeay to be installed (it will be loaded
234automatically when you try to create a TLS handle). 247automatically when you try to create a TLS handle): this module doesn't
248have a dependency on that module, so if your module requires it, you have
249to add the dependency yourself.
235 250
236For the TLS server side, use C<accept>, and for the TLS client side of a 251Unlike TCP, TLS has a server and client side: for the TLS server side, use
237connection, use C<connect> mode. 252C<accept>, and for the TLS client side of a connection, use C<connect>
253mode.
238 254
239You can also provide your own TLS connection object, but you have 255You can also provide your own TLS connection object, but you have
240to make sure that you call either C<Net::SSLeay::set_connect_state> 256to make sure that you call either C<Net::SSLeay::set_connect_state>
241or C<Net::SSLeay::set_accept_state> on it before you pass it to 257or C<Net::SSLeay::set_accept_state> on it before you pass it to
242AnyEvent::Handle. 258AnyEvent::Handle.
243 259
244See the C<starttls> method if you need to start TLS negotiation later. 260See the C<< ->starttls >> method for when need to start TLS negotiation later.
245 261
246=item tls_ctx => $ssl_ctx 262=item tls_ctx => $ssl_ctx
247 263
248Use the given Net::SSLeay::CTX object to create the new TLS connection 264Use the given C<Net::SSLeay::CTX> object to create the new TLS connection
249(unless a connection object was specified directly). If this parameter is 265(unless a connection object was specified directly). If this parameter is
250missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>. 266missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>.
251 267
252=item json => JSON or JSON::XS object 268=item json => JSON or JSON::XS object
253 269
254This is the json coder object used by the C<json> read and write types. 270This is the json coder object used by the C<json> read and write types.
255 271
256If you don't supply it, then AnyEvent::Handle will create and use a 272If you don't supply it, then AnyEvent::Handle will create and use a
257suitable one, which will write and expect UTF-8 encoded JSON texts. 273suitable one (on demand), which will write and expect UTF-8 encoded JSON
274texts.
258 275
259Note that you are responsible to depend on the JSON module if you want to 276Note that you are responsible to depend on the JSON module if you want to
260use this functionality, as AnyEvent does not have a dependency itself. 277use this functionality, as AnyEvent does not have a dependency itself.
261 278
262=item filter_r => $cb
263
264=item filter_w => $cb
265
266These exist, but are undocumented at this time.
267
268=back 279=back
269 280
270=cut 281=cut
271 282
272sub new { 283sub new {
276 287
277 $self->{fh} or Carp::croak "mandatory argument fh is missing"; 288 $self->{fh} or Carp::croak "mandatory argument fh is missing";
278 289
279 AnyEvent::Util::fh_nonblocking $self->{fh}, 1; 290 AnyEvent::Util::fh_nonblocking $self->{fh}, 1;
280 291
281 if ($self->{tls}) {
282 require Net::SSLeay;
283 $self->starttls (delete $self->{tls}, delete $self->{tls_ctx}); 292 $self->starttls (delete $self->{tls}, delete $self->{tls_ctx})
284 } 293 if $self->{tls};
285 294
286 $self->{_activity} = AnyEvent->now; 295 $self->{_activity} = AnyEvent->now;
287 $self->_timeout; 296 $self->_timeout;
288 297
289 $self->on_drain (delete $self->{on_drain}) if exists $self->{on_drain}; 298 $self->on_drain (delete $self->{on_drain}) if exists $self->{on_drain};
301 delete $self->{_tw}; 310 delete $self->{_tw};
302 delete $self->{_rw}; 311 delete $self->{_rw};
303 delete $self->{_ww}; 312 delete $self->{_ww};
304 delete $self->{fh}; 313 delete $self->{fh};
305 314
306 $self->stoptls; 315 &_freetls;
307 316
308 delete $self->{on_read}; 317 delete $self->{on_read};
309 delete $self->{_queue}; 318 delete $self->{_queue};
310} 319}
311 320
317 326
318 $! = $errno; 327 $! = $errno;
319 328
320 if ($self->{on_error}) { 329 if ($self->{on_error}) {
321 $self->{on_error}($self, $fatal); 330 $self->{on_error}($self, $fatal);
322 } else { 331 } elsif ($self->{fh}) {
323 Carp::croak "AnyEvent::Handle uncaught error: $!"; 332 Carp::croak "AnyEvent::Handle uncaught error: $!";
324 } 333 }
325} 334}
326 335
327=item $fh = $handle->fh 336=item $fh = $handle->fh
328 337
329This method returns the file handle of the L<AnyEvent::Handle> object. 338This method returns the file handle used to create the L<AnyEvent::Handle> object.
330 339
331=cut 340=cut
332 341
333sub fh { $_[0]{fh} } 342sub fh { $_[0]{fh} }
334 343
352 $_[0]{on_eof} = $_[1]; 361 $_[0]{on_eof} = $_[1];
353} 362}
354 363
355=item $handle->on_timeout ($cb) 364=item $handle->on_timeout ($cb)
356 365
357Replace the current C<on_timeout> callback, or disables the callback 366Replace the current C<on_timeout> callback, or disables the callback (but
358(but not the timeout) if C<$cb> = C<undef>. See C<timeout> constructor 367not the timeout) if C<$cb> = C<undef>. See the C<timeout> constructor
359argument. 368argument and method.
360 369
361=cut 370=cut
362 371
363sub on_timeout { 372sub on_timeout {
364 $_[0]{on_timeout} = $_[1]; 373 $_[0]{on_timeout} = $_[1];
365} 374}
366 375
367=item $handle->autocork ($boolean) 376=item $handle->autocork ($boolean)
368 377
369Enables or disables the current autocork behaviour (see C<autocork> 378Enables or disables the current autocork behaviour (see C<autocork>
370constructor argument). 379constructor argument). Changes will only take effect on the next write.
371 380
372=cut 381=cut
382
383sub autocork {
384 $_[0]{autocork} = $_[1];
385}
373 386
374=item $handle->no_delay ($boolean) 387=item $handle->no_delay ($boolean)
375 388
376Enables or disables the C<no_delay> setting (see constructor argument of 389Enables or disables the C<no_delay> setting (see constructor argument of
377the same name for details). 390the same name for details).
470 my ($self, $cb) = @_; 483 my ($self, $cb) = @_;
471 484
472 $self->{on_drain} = $cb; 485 $self->{on_drain} = $cb;
473 486
474 $cb->($self) 487 $cb->($self)
475 if $cb && $self->{low_water_mark} >= length $self->{wbuf}; 488 if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf});
476} 489}
477 490
478=item $handle->push_write ($data) 491=item $handle->push_write ($data)
479 492
480Queues the given scalar to be written. You can push as much data as you 493Queues the given scalar to be written. You can push as much data as you
497 substr $self->{wbuf}, 0, $len, ""; 510 substr $self->{wbuf}, 0, $len, "";
498 511
499 $self->{_activity} = AnyEvent->now; 512 $self->{_activity} = AnyEvent->now;
500 513
501 $self->{on_drain}($self) 514 $self->{on_drain}($self)
502 if $self->{low_water_mark} >= length $self->{wbuf} 515 if $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf})
503 && $self->{on_drain}; 516 && $self->{on_drain};
504 517
505 delete $self->{_ww} unless length $self->{wbuf}; 518 delete $self->{_ww} unless length $self->{wbuf};
506 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) { 519 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
507 $self->_error ($!, 1); 520 $self->_error ($!, 1);
531 544
532 @_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write") 545 @_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write")
533 ->($self, @_); 546 ->($self, @_);
534 } 547 }
535 548
536 if ($self->{filter_w}) { 549 if ($self->{tls}) {
537 $self->{filter_w}($self, \$_[0]); 550 $self->{_tls_wbuf} .= $_[0];
551
552 &_dotls ($self);
538 } else { 553 } else {
539 $self->{wbuf} .= $_[0]; 554 $self->{wbuf} .= $_[0];
540 $self->_drain_wbuf; 555 $self->_drain_wbuf;
541 } 556 }
542} 557}
559=cut 574=cut
560 575
561register_write_type netstring => sub { 576register_write_type netstring => sub {
562 my ($self, $string) = @_; 577 my ($self, $string) = @_;
563 578
564 sprintf "%d:%s,", (length $string), $string 579 (length $string) . ":$string,"
565}; 580};
566 581
567=item packstring => $format, $data 582=item packstring => $format, $data
568 583
569An octet string prefixed with an encoded length. The encoding C<$format> 584An octet string prefixed with an encoded length. The encoding C<$format>
778 793
779 last; # more data might arrive 794 last; # more data might arrive
780 } 795 }
781 } else { 796 } else {
782 # read side becomes idle 797 # read side becomes idle
783 delete $self->{_rw}; 798 delete $self->{_rw} unless $self->{tls};
784 last; 799 last;
785 } 800 }
786 } 801 }
787 802
788 if ($self->{_eof}) { 803 if ($self->{_eof}) {
1083An octet string prefixed with an encoded length. The encoding C<$format> 1098An octet string prefixed with an encoded length. The encoding C<$format>
1084uses the same format as a Perl C<pack> format, but must specify a single 1099uses the same format as a Perl C<pack> format, but must specify a single
1085integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an 1100integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
1086optional C<!>, C<< < >> or C<< > >> modifier). 1101optional C<!>, C<< < >> or C<< > >> modifier).
1087 1102
1088DNS over TCP uses a prefix of C<n>, EPP uses a prefix of C<N>. 1103For example, DNS over TCP uses a prefix of C<n> (2 octet network order),
1104EPP uses a prefix of C<N> (4 octtes).
1089 1105
1090Example: read a block of data prefixed by its length in BER-encoded 1106Example: read a block of data prefixed by its length in BER-encoded
1091format (very efficient). 1107format (very efficient).
1092 1108
1093 $handle->push_read (packstring => "w", sub { 1109 $handle->push_read (packstring => "w", sub {
1246Note that AnyEvent::Handle will automatically C<start_read> for you when 1262Note that AnyEvent::Handle will automatically C<start_read> for you when
1247you change the C<on_read> callback or push/unshift a read callback, and it 1263you change the C<on_read> callback or push/unshift a read callback, and it
1248will automatically C<stop_read> for you when neither C<on_read> is set nor 1264will automatically C<stop_read> for you when neither C<on_read> is set nor
1249there are any read requests in the queue. 1265there are any read requests in the queue.
1250 1266
1267These methods will have no effect when in TLS mode (as TLS doesn't support
1268half-duplex connections).
1269
1251=cut 1270=cut
1252 1271
1253sub stop_read { 1272sub stop_read {
1254 my ($self) = @_; 1273 my ($self) = @_;
1255 1274
1256 delete $self->{_rw}; 1275 delete $self->{_rw} unless $self->{tls};
1257} 1276}
1258 1277
1259sub start_read { 1278sub start_read {
1260 my ($self) = @_; 1279 my ($self) = @_;
1261 1280
1262 unless ($self->{_rw} || $self->{_eof}) { 1281 unless ($self->{_rw} || $self->{_eof}) {
1263 Scalar::Util::weaken $self; 1282 Scalar::Util::weaken $self;
1264 1283
1265 $self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub { 1284 $self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub {
1266 my $rbuf = $self->{filter_r} ? \my $buf : \$self->{rbuf}; 1285 my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf});
1267 my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf; 1286 my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf;
1268 1287
1269 if ($len > 0) { 1288 if ($len > 0) {
1270 $self->{_activity} = AnyEvent->now; 1289 $self->{_activity} = AnyEvent->now;
1271 1290
1272 $self->{filter_r} 1291 if ($self->{tls}) {
1273 ? $self->{filter_r}($self, $rbuf) 1292 Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf);
1274 : $self->{_in_drain} || $self->_drain_rbuf; 1293
1294 &_dotls ($self);
1295 } else {
1296 $self->_drain_rbuf unless $self->{_in_drain};
1297 }
1275 1298
1276 } elsif (defined $len) { 1299 } elsif (defined $len) {
1277 delete $self->{_rw}; 1300 delete $self->{_rw};
1278 $self->{_eof} = 1; 1301 $self->{_eof} = 1;
1279 $self->_drain_rbuf unless $self->{_in_drain}; 1302 $self->_drain_rbuf unless $self->{_in_drain};
1283 } 1306 }
1284 }); 1307 });
1285 } 1308 }
1286} 1309}
1287 1310
1311# poll the write BIO and send the data if applicable
1288sub _dotls { 1312sub _dotls {
1289 my ($self) = @_; 1313 my ($self) = @_;
1290 1314
1291 my $buf; 1315 my $tmp;
1292 1316
1293 if (length $self->{_tls_wbuf}) { 1317 if (length $self->{_tls_wbuf}) {
1294 while ((my $len = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) { 1318 while (($tmp = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) {
1295 substr $self->{_tls_wbuf}, 0, $len, ""; 1319 substr $self->{_tls_wbuf}, 0, $tmp, "";
1296 } 1320 }
1297 } 1321 }
1298 1322
1299 if (length ($buf = Net::SSLeay::BIO_read ($self->{_wbio}))) {
1300 $self->{wbuf} .= $buf;
1301 $self->_drain_wbuf;
1302 }
1303
1304 while (defined ($buf = Net::SSLeay::read ($self->{tls}))) { 1323 while (defined ($tmp = Net::SSLeay::read ($self->{tls}))) {
1305 if (length $buf) { 1324 unless (length $tmp) {
1306 $self->{rbuf} .= $buf;
1307 $self->_drain_rbuf unless $self->{_in_drain};
1308 } else {
1309 # let's treat SSL-eof as we treat normal EOF 1325 # let's treat SSL-eof as we treat normal EOF
1326 delete $self->{_rw};
1310 $self->{_eof} = 1; 1327 $self->{_eof} = 1;
1311 $self->_shutdown; 1328 &_freetls;
1312 return;
1313 } 1329 }
1314 }
1315 1330
1331 $self->{rbuf} .= $tmp;
1332 $self->_drain_rbuf unless $self->{_in_drain};
1333 $self->{tls} or return; # tls session might have gone away in callback
1334 }
1335
1316 my $err = Net::SSLeay::get_error ($self->{tls}, -1); 1336 $tmp = Net::SSLeay::get_error ($self->{tls}, -1);
1317 1337
1318 if ($err!= Net::SSLeay::ERROR_WANT_READ ()) { 1338 if ($tmp != Net::SSLeay::ERROR_WANT_READ ()) {
1319 if ($err == Net::SSLeay::ERROR_SYSCALL ()) { 1339 if ($tmp == Net::SSLeay::ERROR_SYSCALL ()) {
1320 return $self->_error ($!, 1); 1340 return $self->_error ($!, 1);
1321 } elsif ($err == Net::SSLeay::ERROR_SSL ()) { 1341 } elsif ($tmp == Net::SSLeay::ERROR_SSL ()) {
1322 return $self->_error (&Errno::EIO, 1); 1342 return $self->_error (&Errno::EIO, 1);
1323 } 1343 }
1324 1344
1325 # all others are fine for our purposes 1345 # all other errors are fine for our purposes
1346 }
1347
1348 while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) {
1349 $self->{wbuf} .= $tmp;
1350 $self->_drain_wbuf;
1326 } 1351 }
1327} 1352}
1328 1353
1329=item $handle->starttls ($tls[, $tls_ctx]) 1354=item $handle->starttls ($tls[, $tls_ctx])
1330 1355
1340 1365
1341The TLS connection object will end up in C<< $handle->{tls} >> after this 1366The TLS connection object will end up in C<< $handle->{tls} >> after this
1342call and can be used or changed to your liking. Note that the handshake 1367call and can be used or changed to your liking. Note that the handshake
1343might have already started when this function returns. 1368might have already started when this function returns.
1344 1369
1370If it an error to start a TLS handshake more than once per
1371AnyEvent::Handle object (this is due to bugs in OpenSSL).
1372
1345=cut 1373=cut
1346 1374
1347sub starttls { 1375sub starttls {
1348 my ($self, $ssl, $ctx) = @_; 1376 my ($self, $ssl, $ctx) = @_;
1349 1377
1350 $self->stoptls; 1378 require Net::SSLeay;
1351 1379
1380 Carp::croak "it is an error to call starttls more than once on an AnyEvent::Handle object"
1381 if $self->{tls};
1382
1352 if ($ssl eq "accept") { 1383 if ($ssl eq "accept") {
1353 $ssl = Net::SSLeay::new ($ctx || TLS_CTX ()); 1384 $ssl = Net::SSLeay::new ($ctx || TLS_CTX ());
1354 Net::SSLeay::set_accept_state ($ssl); 1385 Net::SSLeay::set_accept_state ($ssl);
1355 } elsif ($ssl eq "connect") { 1386 } elsif ($ssl eq "connect") {
1356 $ssl = Net::SSLeay::new ($ctx || TLS_CTX ()); 1387 $ssl = Net::SSLeay::new ($ctx || TLS_CTX ());
1362 # basically, this is deep magic (because SSL_read should have the same issues) 1393 # basically, this is deep magic (because SSL_read should have the same issues)
1363 # but the openssl maintainers basically said: "trust us, it just works". 1394 # but the openssl maintainers basically said: "trust us, it just works".
1364 # (unfortunately, we have to hardcode constants because the abysmally misdesigned 1395 # (unfortunately, we have to hardcode constants because the abysmally misdesigned
1365 # and mismaintained ssleay-module doesn't even offer them). 1396 # and mismaintained ssleay-module doesn't even offer them).
1366 # http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html 1397 # http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html
1398 #
1399 # in short: this is a mess.
1400 #
1401 # note that we do not try to keep the length constant between writes as we are required to do.
1402 # we assume that most (but not all) of this insanity only applies to non-blocking cases,
1403 # and we drive openssl fully in blocking mode here. Or maybe we don't - openssl seems to
1404 # have identity issues in that area.
1367 Net::SSLeay::CTX_set_mode ($self->{tls}, 1405 Net::SSLeay::CTX_set_mode ($self->{tls},
1368 (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1) 1406 (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)
1369 | (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2)); 1407 | (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2));
1370 1408
1371 $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); 1409 $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1372 $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); 1410 $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1373 1411
1374 Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio}); 1412 Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio});
1375 1413
1376 $self->{filter_w} = sub { 1414 &_dotls; # need to trigger the initial handshake
1377 $_[0]{_tls_wbuf} .= ${$_[1]}; 1415 $self->start_read; # make sure we actually do read
1378 &_dotls;
1379 };
1380 $self->{filter_r} = sub {
1381 Net::SSLeay::BIO_write ($_[0]{_rbio}, ${$_[1]});
1382 &_dotls;
1383 };
1384} 1416}
1385 1417
1386=item $handle->stoptls 1418=item $handle->stoptls
1387 1419
1388Destroys the SSL connection, if any. Partial read or write data will be 1420Shuts down the SSL connection - this makes a proper EOF handshake by
1389lost. 1421sending a close notify to the other side, but since OpenSSL doesn't
1422support non-blocking shut downs, it is not possible to re-use the stream
1423afterwards.
1390 1424
1391=cut 1425=cut
1392 1426
1393sub stoptls { 1427sub stoptls {
1394 my ($self) = @_; 1428 my ($self) = @_;
1395 1429
1430 if ($self->{tls}) {
1431 Net::SSLeay::shutdown ($self->{tls});
1432
1433 &_dotls;
1434
1435 # we don't give a shit. no, we do, but we can't. no...
1436 # we, we... have to use openssl :/
1437 &_freetls;
1438 }
1439}
1440
1441sub _freetls {
1442 my ($self) = @_;
1443
1444 return unless $self->{tls};
1445
1396 Net::SSLeay::free (delete $self->{tls}) if $self->{tls}; 1446 Net::SSLeay::free (delete $self->{tls});
1397 1447
1398 delete $self->{_rbio}; 1448 delete @$self{qw(_rbio _wbio _tls_wbuf)};
1399 delete $self->{_wbio};
1400 delete $self->{_tls_wbuf};
1401 delete $self->{filter_r};
1402 delete $self->{filter_w};
1403} 1449}
1404 1450
1405sub DESTROY { 1451sub DESTROY {
1406 my $self = shift; 1452 my $self = shift;
1407 1453
1408 $self->stoptls; 1454 &_freetls;
1409 1455
1410 my $linger = exists $self->{linger} ? $self->{linger} : 3600; 1456 my $linger = exists $self->{linger} ? $self->{linger} : 3600;
1411 1457
1412 if ($linger && length $self->{wbuf}) { 1458 if ($linger && length $self->{wbuf}) {
1413 my $fh = delete $self->{fh}; 1459 my $fh = delete $self->{fh};
1428 @linger = (); 1474 @linger = ();
1429 }); 1475 });
1430 } 1476 }
1431} 1477}
1432 1478
1479=item $handle->destroy
1480
1481Shuts down the handle object as much as possible - this call ensures that
1482no further callbacks will be invoked and resources will be freed as much
1483as possible. You must not call any methods on the object afterwards.
1484
1485Normally, you can just "forget" any references to an AnyEvent::Handle
1486object and it will simply shut down. This works in fatal error and EOF
1487callbacks, as well as code outside. It does I<NOT> work in a read or write
1488callback, so when you want to destroy the AnyEvent::Handle object from
1489within such an callback. You I<MUST> call C<< ->destroy >> explicitly in
1490that case.
1491
1492The handle might still linger in the background and write out remaining
1493data, as specified by the C<linger> option, however.
1494
1495=cut
1496
1497sub destroy {
1498 my ($self) = @_;
1499
1500 $self->DESTROY;
1501 %$self = ();
1502}
1503
1433=item AnyEvent::Handle::TLS_CTX 1504=item AnyEvent::Handle::TLS_CTX
1434 1505
1435This function creates and returns the Net::SSLeay::CTX object used by 1506This function creates and returns the Net::SSLeay::CTX object used by
1436default for TLS mode. 1507default for TLS mode.
1437 1508
1465 } 1536 }
1466} 1537}
1467 1538
1468=back 1539=back
1469 1540
1541
1542=head1 NONFREQUENTLY ASKED QUESTIONS
1543
1544=over 4
1545
1546=item I C<undef> the AnyEvent::Handle reference inside my callback and
1547still get further invocations!
1548
1549That's because AnyEvent::Handle keeps a reference to itself when handling
1550read or write callbacks.
1551
1552It is only safe to "forget" the reference inside EOF or error callbacks,
1553from within all other callbacks, you need to explicitly call the C<<
1554->destroy >> method.
1555
1556=item I get different callback invocations in TLS mode/Why can't I pause
1557reading?
1558
1559Unlike, say, TCP, TLS connections do not consist of two independent
1560communication channels, one for each direction. Or put differently. The
1561read and write directions are not independent of each other: you cannot
1562write data unless you are also prepared to read, and vice versa.
1563
1564This can mean than, in TLS mode, you might get C<on_error> or C<on_eof>
1565callback invocations when you are not expecting any read data - the reason
1566is that AnyEvent::Handle always reads in TLS mode.
1567
1568During the connection, you have to make sure that you always have a
1569non-empty read-queue, or an C<on_read> watcher. At the end of the
1570connection (or when you no longer want to use it) you can call the
1571C<destroy> method.
1572
1573=item How do I read data until the other side closes the connection?
1574
1575If you just want to read your data into a perl scalar, the easiest way
1576to achieve this is by setting an C<on_read> callback that does nothing,
1577clearing the C<on_eof> callback and in the C<on_error> callback, the data
1578will be in C<$_[0]{rbuf}>:
1579
1580 $handle->on_read (sub { });
1581 $handle->on_eof (undef);
1582 $handle->on_error (sub {
1583 my $data = delete $_[0]{rbuf};
1584 undef $handle;
1585 });
1586
1587The reason to use C<on_error> is that TCP connections, due to latencies
1588and packets loss, might get closed quite violently with an error, when in
1589fact, all data has been received.
1590
1591It is usually better to use acknowledgements when transferring data,
1592to make sure the other side hasn't just died and you got the data
1593intact. This is also one reason why so many internet protocols have an
1594explicit QUIT command.
1595
1596=item I don't want to destroy the handle too early - how do I wait until
1597all data has been written?
1598
1599After writing your last bits of data, set the C<on_drain> callback
1600and destroy the handle in there - with the default setting of
1601C<low_water_mark> this will be called precisely when all data has been
1602written to the socket:
1603
1604 $handle->push_write (...);
1605 $handle->on_drain (sub {
1606 warn "all data submitted to the kernel\n";
1607 undef $handle;
1608 });
1609
1610=back
1611
1612
1470=head1 SUBCLASSING AnyEvent::Handle 1613=head1 SUBCLASSING AnyEvent::Handle
1471 1614
1472In many cases, you might want to subclass AnyEvent::Handle. 1615In many cases, you might want to subclass AnyEvent::Handle.
1473 1616
1474To make this easier, a given version of AnyEvent::Handle uses these 1617To make this easier, a given version of AnyEvent::Handle uses these

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