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Comparing AnyEvent/lib/AnyEvent/Handle.pm (file contents):
Revision 1.9 by root, Fri May 2 16:07:46 2008 UTC vs.
Revision 1.57 by root, Wed Jun 4 11:45:21 2008 UTC

2 2
3no warnings; 3no warnings;
4use strict; 4use strict;
5 5
6use AnyEvent (); 6use AnyEvent ();
7use AnyEvent::Util (); 7use AnyEvent::Util qw(WSAEWOULDBLOCK);
8use Scalar::Util (); 8use Scalar::Util ();
9use Carp (); 9use Carp ();
10use Fcntl (); 10use Fcntl ();
11use Errno qw/EAGAIN EINTR/; 11use Errno qw(EAGAIN EINTR);
12 12
13=head1 NAME 13=head1 NAME
14 14
15AnyEvent::Handle - non-blocking I/O on filehandles via AnyEvent 15AnyEvent::Handle - non-blocking I/O on file handles via AnyEvent
16 16
17=cut 17=cut
18 18
19our $VERSION = '0.02'; 19our $VERSION = 4.13;
20 20
21=head1 SYNOPSIS 21=head1 SYNOPSIS
22 22
23 use AnyEvent; 23 use AnyEvent;
24 use AnyEvent::Handle; 24 use AnyEvent::Handle;
25 25
26 my $cv = AnyEvent->condvar; 26 my $cv = AnyEvent->condvar;
27 27
28 my $ae_fh = AnyEvent::Handle->new (fh => \*STDIN); 28 my $handle =
29
30 #TODO
31
32 # or use the constructor to pass the callback:
33
34 my $ae_fh2 =
35 AnyEvent::Handle->new ( 29 AnyEvent::Handle->new (
36 fh => \*STDIN, 30 fh => \*STDIN,
37 on_eof => sub { 31 on_eof => sub {
38 $cv->broadcast; 32 $cv->broadcast;
39 }, 33 },
40 #TODO
41 ); 34 );
42 35
43 $cv->wait; 36 # send some request line
37 $handle->push_write ("getinfo\015\012");
38
39 # read the response line
40 $handle->push_read (line => sub {
41 my ($handle, $line) = @_;
42 warn "read line <$line>\n";
43 $cv->send;
44 });
45
46 $cv->recv;
44 47
45=head1 DESCRIPTION 48=head1 DESCRIPTION
46 49
47This 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
48filehandles (and sockets, see L<AnyEvent::Socket> for an easy way to make 51filehandles. For utility functions for doing non-blocking connects and accepts
49non-blocking resolves and connects). 52on sockets see L<AnyEvent::Util>.
50 53
51In the following, when the documentation refers to of "bytes" then this 54In the following, when the documentation refers to of "bytes" then this
52means characters. As sysread and syswrite are used for all I/O, their 55means characters. As sysread and syswrite are used for all I/O, their
53treatment of characters applies to this module as well. 56treatment of characters applies to this module as well.
54 57
70The filehandle this L<AnyEvent::Handle> object will operate on. 73The filehandle this L<AnyEvent::Handle> object will operate on.
71 74
72NOTE: The filehandle will be set to non-blocking (using 75NOTE: The filehandle will be set to non-blocking (using
73AnyEvent::Util::fh_nonblocking). 76AnyEvent::Util::fh_nonblocking).
74 77
75=item on_error => $cb->($self) [MANDATORY] 78=item on_eof => $cb->($handle)
76 79
77This is the fatal error callback, that is called when a fatal error ocurs, 80Set the callback to be called when an end-of-file condition is detcted,
81i.e. in the case of a socket, when the other side has closed the
82connection cleanly.
83
84While not mandatory, it is highly recommended to set an eof callback,
85otherwise you might end up with a closed socket while you are still
86waiting for data.
87
88=item on_error => $cb->($handle, $fatal)
89
90This is the error callback, which is called when, well, some error
78such as not being able to resolve the hostname, failure to connect or a 91occured, such as not being able to resolve the hostname, failure to
79read error. 92connect or a read error.
80 93
81The object will not be in a usable state when this callback has been 94Some errors are fatal (which is indicated by C<$fatal> being true). On
82called. 95fatal errors the handle object will be shut down and will not be
96usable. Non-fatal errors can be retried by simply returning, but it is
97recommended to simply ignore this parameter and instead abondon the handle
98object when this callback is invoked.
83 99
84On callback entrance, the value of C<$!> contains the opertaing system 100On callback entrance, the value of C<$!> contains the operating system
85error (or C<ENOSPC> or C<EPIPE>). 101error (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT> or C<EBADMSG>).
86 102
87=item on_eof => $cb->($self) [MANDATORY] 103While not mandatory, it is I<highly> recommended to set this callback, as
104you will not be notified of errors otherwise. The default simply calls
105C<croak>.
88 106
89Set the callback to be called on EOF.
90
91=item on_read => $cb->($self) 107=item on_read => $cb->($handle)
92 108
93This sets the default read callback, which is called when data arrives 109This sets the default read callback, which is called when data arrives
94and no read request is in the queue. If the read callback is C<undef> 110and no read request is in the queue.
95or has never been set, than AnyEvent::Handle will cease reading from the
96filehandle.
97 111
98To access (and remove data from) the read buffer, use the C<< ->rbuf >> 112To access (and remove data from) the read buffer, use the C<< ->rbuf >>
99method or acces sthe C<$self->{rbuf}> member directly. 113method or access the C<$handle->{rbuf}> member directly.
100 114
101When an EOF condition is detected then AnyEvent::Handle will first try to 115When an EOF condition is detected then AnyEvent::Handle will first try to
102feed all the remaining data to the queued callbacks and C<on_read> before 116feed all the remaining data to the queued callbacks and C<on_read> before
103calling the C<on_eof> callback. If no progress can be made, then a fatal 117calling the C<on_eof> callback. If no progress can be made, then a fatal
104error will be raised (with C<$!> set to C<EPIPE>). 118error will be raised (with C<$!> set to C<EPIPE>).
105 119
106=item on_drain => $cb->() 120=item on_drain => $cb->($handle)
107 121
108This sets the callback that is called when the write buffer becomes empty 122This sets the callback that is called when the write buffer becomes empty
109(or when the callback is set and the buffer is empty already). 123(or when the callback is set and the buffer is empty already).
110 124
111To append to the write buffer, use the C<< ->push_write >> method. 125To append to the write buffer, use the C<< ->push_write >> method.
126
127=item timeout => $fractional_seconds
128
129If non-zero, then this enables an "inactivity" timeout: whenever this many
130seconds 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
132missing, an C<ETIMEDOUT> error will be raised).
133
134Note 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
136idle then you should disable the timout temporarily or ignore the timeout
137in the C<on_timeout> callback.
138
139Zero (the default) disables this timeout.
140
141=item on_timeout => $cb->($handle)
142
143Called whenever the inactivity timeout passes. If you return from this
144callback, then the timeout will be reset as if some activity had happened,
145so this condition is not fatal in any way.
112 146
113=item rbuf_max => <bytes> 147=item rbuf_max => <bytes>
114 148
115If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>) 149If defined, then a fatal error will be raised (with C<$!> set to C<ENOSPC>)
116when the read buffer ever (strictly) exceeds this size. This is useful to 150when the read buffer ever (strictly) exceeds this size. This is useful to
123isn't finished). 157isn't finished).
124 158
125=item read_size => <bytes> 159=item read_size => <bytes>
126 160
127The default read block size (the amount of bytes this module will try to read 161The default read block size (the amount of bytes this module will try to read
128on each [loop iteration). Default: C<4096>. 162during each (loop iteration). Default: C<8192>.
129 163
130=item low_water_mark => <bytes> 164=item low_water_mark => <bytes>
131 165
132Sets the amount of bytes (default: C<0>) that make up an "empty" write 166Sets the amount of bytes (default: C<0>) that make up an "empty" write
133buffer: If the write reaches this size or gets even samller it is 167buffer: If the write reaches this size or gets even samller it is
134considered empty. 168considered empty.
135 169
170=item tls => "accept" | "connect" | Net::SSLeay::SSL object
171
172When this parameter is given, it enables TLS (SSL) mode, that means it
173will start making tls handshake and will transparently encrypt/decrypt
174data.
175
176TLS mode requires Net::SSLeay to be installed (it will be loaded
177automatically when you try to create a TLS handle).
178
179For the TLS server side, use C<accept>, and for the TLS client side of a
180connection, use C<connect> mode.
181
182You can also provide your own TLS connection object, but you have
183to 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
185AnyEvent::Handle.
186
187See the C<starttls> method if you need to start TLs negotiation later.
188
189=item tls_ctx => $ssl_ctx
190
191Use the given Net::SSLeay::CTX object to create the new TLS connection
192(unless a connection object was specified directly). If this parameter is
193missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>.
194
195=item json => JSON or JSON::XS object
196
197This is the json coder object used by the C<json> read and write types.
198
199If 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.
201
202Note 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.
204
205=item filter_r => $cb
206
207=item filter_w => $cb
208
209These exist, but are undocumented at this time.
210
136=back 211=back
137 212
138=cut 213=cut
139 214
140sub new { 215sub new {
144 219
145 $self->{fh} or Carp::croak "mandatory argument fh is missing"; 220 $self->{fh} or Carp::croak "mandatory argument fh is missing";
146 221
147 AnyEvent::Util::fh_nonblocking $self->{fh}, 1; 222 AnyEvent::Util::fh_nonblocking $self->{fh}, 1;
148 223
149 $self->on_error ((delete $self->{on_error}) or Carp::croak "mandatory argument on_error is missing"); 224 if ($self->{tls}) {
150 $self->on_eof ((delete $self->{on_eof} ) or Carp::croak "mandatory argument on_eof is missing"); 225 require Net::SSLeay;
226 $self->starttls (delete $self->{tls}, delete $self->{tls_ctx});
227 }
151 228
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
152 $self->on_drain (delete $self->{on_drain}) if $self->{on_drain}; 232 $self->on_drain (delete $self->{on_drain}) if $self->{on_drain};
153 $self->on_read (delete $self->{on_read} ) if $self->{on_read}; 233
234 $self->{_activity} = AnyEvent->now;
235 $self->_timeout;
236
237 $self->start_read;
154 238
155 $self 239 $self
156} 240}
157 241
158sub _shutdown { 242sub _shutdown {
159 my ($self) = @_; 243 my ($self) = @_;
160 244
245 delete $self->{_tw};
161 delete $self->{rw}; 246 delete $self->{_rw};
162 delete $self->{ww}; 247 delete $self->{_ww};
163 delete $self->{fh}; 248 delete $self->{fh};
164}
165 249
250 $self->stoptls;
251}
252
166sub error { 253sub _error {
167 my ($self) = @_; 254 my ($self, $errno, $fatal) = @_;
168 255
169 {
170 local $!;
171 $self->_shutdown; 256 $self->_shutdown
172 } 257 if $fatal;
173 258
259 $! = $errno;
260
261 if ($self->{on_error}) {
174 $self->{on_error}($self); 262 $self->{on_error}($self, $fatal);
263 } else {
264 Carp::croak "AnyEvent::Handle uncaught error: $!";
265 }
175} 266}
176 267
177=item $fh = $handle->fh 268=item $fh = $handle->fh
178 269
179This method returns the filehandle of the L<AnyEvent::Handle> object. 270This method returns the file handle of the L<AnyEvent::Handle> object.
180 271
181=cut 272=cut
182 273
183sub fh { $_[0]->{fh} } 274sub fh { $_[0]{fh} }
184 275
185=item $handle->on_error ($cb) 276=item $handle->on_error ($cb)
186 277
187Replace the current C<on_error> callback (see the C<on_error> constructor argument). 278Replace the current C<on_error> callback (see the C<on_error> constructor argument).
188 279
200 291
201sub on_eof { 292sub on_eof {
202 $_[0]{on_eof} = $_[1]; 293 $_[0]{on_eof} = $_[1];
203} 294}
204 295
296=item $handle->on_timeout ($cb)
297
298Replace the current C<on_timeout> callback, or disables the callback
299(but not the timeout) if C<$cb> = C<undef>. See C<timeout> constructor
300argument.
301
302=cut
303
304sub on_timeout {
305 $_[0]{on_timeout} = $_[1];
306}
307
308#############################################################################
309
310=item $handle->timeout ($seconds)
311
312Configures (or disables) the inactivity timeout.
313
314=cut
315
316sub timeout {
317 my ($self, $timeout) = @_;
318
319 $self->{timeout} = $timeout;
320 $self->_timeout;
321}
322
323# reset the timeout watcher, as neccessary
324# also check for time-outs
325sub _timeout {
326 my ($self) = @_;
327
328 if ($self->{timeout}) {
329 my $NOW = AnyEvent->now;
330
331 # when would the timeout trigger?
332 my $after = $self->{_activity} + $self->{timeout} - $NOW;
333
334 # now or in the past already?
335 if ($after <= 0) {
336 $self->{_activity} = $NOW;
337
338 if ($self->{on_timeout}) {
339 $self->{on_timeout}($self);
340 } else {
341 $self->_error (&Errno::ETIMEDOUT);
342 }
343
344 # callback could have changed timeout value, optimise
345 return unless $self->{timeout};
346
347 # calculate new after
348 $after = $self->{timeout};
349 }
350
351 Scalar::Util::weaken $self;
352 return unless $self; # ->error could have destroyed $self
353
354 $self->{_tw} ||= AnyEvent->timer (after => $after, cb => sub {
355 delete $self->{_tw};
356 $self->_timeout;
357 });
358 } else {
359 delete $self->{_tw};
360 }
361}
362
205############################################################################# 363#############################################################################
206 364
207=back 365=back
208 366
209=head2 WRITE QUEUE 367=head2 WRITE QUEUE
212for reading. 370for reading.
213 371
214The write queue is very simple: you can add data to its end, and 372The write queue is very simple: you can add data to its end, and
215AnyEvent::Handle will automatically try to get rid of it for you. 373AnyEvent::Handle will automatically try to get rid of it for you.
216 374
217When data could be writtena nd the write buffer is shorter then the low 375When data could be written and the write buffer is shorter then the low
218water mark, the C<on_drain> callback will be invoked. 376water mark, the C<on_drain> callback will be invoked.
219 377
220=over 4 378=over 4
221 379
222=item $handle->on_drain ($cb) 380=item $handle->on_drain ($cb)
241want (only limited by the available memory), as C<AnyEvent::Handle> 399want (only limited by the available memory), as C<AnyEvent::Handle>
242buffers it independently of the kernel. 400buffers it independently of the kernel.
243 401
244=cut 402=cut
245 403
246sub push_write { 404sub _drain_wbuf {
247 my ($self, $data) = @_; 405 my ($self) = @_;
248 406
249 $self->{wbuf} .= $data; 407 if (!$self->{_ww} && length $self->{wbuf}) {
250 408
251 unless ($self->{ww}) {
252 Scalar::Util::weaken $self; 409 Scalar::Util::weaken $self;
410
253 my $cb = sub { 411 my $cb = sub {
254 my $len = syswrite $self->{fh}, $self->{wbuf}; 412 my $len = syswrite $self->{fh}, $self->{wbuf};
255 413
256 if ($len > 0) { 414 if ($len >= 0) {
257 substr $self->{wbuf}, 0, $len, ""; 415 substr $self->{wbuf}, 0, $len, "";
258 416
417 $self->{_activity} = AnyEvent->now;
259 418
260 $self->{on_drain}($self) 419 $self->{on_drain}($self)
261 if $self->{low_water_mark} >= length $self->{wbuf} 420 if $self->{low_water_mark} >= length $self->{wbuf}
262 && $self->{on_drain}; 421 && $self->{on_drain};
263 422
264 delete $self->{ww} unless length $self->{wbuf}; 423 delete $self->{_ww} unless length $self->{wbuf};
265 } elsif ($! != EAGAIN && $! != EINTR) { 424 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
266 $self->error; 425 $self->_error ($!, 1);
267 } 426 }
268 }; 427 };
269 428
429 # try to write data immediately
430 $cb->();
431
432 # if still data left in wbuf, we need to poll
270 $self->{ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb); 433 $self->{_ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb)
271 434 if length $self->{wbuf};
272 $cb->($self);
273 }; 435 };
274} 436}
437
438our %WH;
439
440sub register_write_type($$) {
441 $WH{$_[0]} = $_[1];
442}
443
444sub push_write {
445 my $self = shift;
446
447 if (@_ > 1) {
448 my $type = shift;
449
450 @_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write")
451 ->($self, @_);
452 }
453
454 if ($self->{filter_w}) {
455 $self->{filter_w}($self, \$_[0]);
456 } else {
457 $self->{wbuf} .= $_[0];
458 $self->_drain_wbuf;
459 }
460}
461
462=item $handle->push_write (type => @args)
463
464Instead of formatting your data yourself, you can also let this module do
465the job by specifying a type and type-specific arguments.
466
467Predefined types are (if you have ideas for additional types, feel free to
468drop by and tell us):
469
470=over 4
471
472=item netstring => $string
473
474Formats the given value as netstring
475(http://cr.yp.to/proto/netstrings.txt, this is not a recommendation to use them).
476
477=cut
478
479register_write_type netstring => sub {
480 my ($self, $string) = @_;
481
482 sprintf "%d:%s,", (length $string), $string
483};
484
485=item json => $array_or_hashref
486
487Encodes the given hash or array reference into a JSON object. Unless you
488provide your own JSON object, this means it will be encoded to JSON text
489in UTF-8.
490
491JSON objects (and arrays) are self-delimiting, so you can write JSON at
492one end of a handle and read them at the other end without using any
493additional framing.
494
495The generated JSON text is guaranteed not to contain any newlines: While
496this module doesn't need delimiters after or between JSON texts to be
497able to read them, many other languages depend on that.
498
499A simple RPC protocol that interoperates easily with others is to send
500JSON arrays (or objects, although arrays are usually the better choice as
501they mimic how function argument passing works) and a newline after each
502JSON text:
503
504 $handle->push_write (json => ["method", "arg1", "arg2"]); # whatever
505 $handle->push_write ("\012");
506
507An AnyEvent::Handle receiver would simply use the C<json> read type and
508rely on the fact that the newline will be skipped as leading whitespace:
509
510 $handle->push_read (json => sub { my $array = $_[1]; ... });
511
512Other languages could read single lines terminated by a newline and pass
513this line into their JSON decoder of choice.
514
515=cut
516
517register_write_type json => sub {
518 my ($self, $ref) = @_;
519
520 require JSON;
521
522 $self->{json} ? $self->{json}->encode ($ref)
523 : JSON::encode_json ($ref)
524};
525
526=back
527
528=item AnyEvent::Handle::register_write_type type => $coderef->($handle, @args)
529
530This function (not method) lets you add your own types to C<push_write>.
531Whenever the given C<type> is used, C<push_write> will invoke the code
532reference with the handle object and the remaining arguments.
533
534The code reference is supposed to return a single octet string that will
535be appended to the write buffer.
536
537Note that this is a function, and all types registered this way will be
538global, so try to use unique names.
539
540=cut
275 541
276############################################################################# 542#############################################################################
277 543
278=back 544=back
279 545
303the specified number of bytes which give an XML datagram. 569the specified number of bytes which give an XML datagram.
304 570
305 # in the default state, expect some header bytes 571 # in the default state, expect some header bytes
306 $handle->on_read (sub { 572 $handle->on_read (sub {
307 # some data is here, now queue the length-header-read (4 octets) 573 # some data is here, now queue the length-header-read (4 octets)
308 shift->unshift_read_chunk (4, sub { 574 shift->unshift_read (chunk => 4, sub {
309 # header arrived, decode 575 # header arrived, decode
310 my $len = unpack "N", $_[1]; 576 my $len = unpack "N", $_[1];
311 577
312 # now read the payload 578 # now read the payload
313 shift->unshift_read_chunk ($len, sub { 579 shift->unshift_read (chunk => $len, sub {
314 my $xml = $_[1]; 580 my $xml = $_[1];
315 # handle xml 581 # handle xml
316 }); 582 });
317 }); 583 });
318 }); 584 });
325 591
326 # request one 592 # request one
327 $handle->push_write ("request 1\015\012"); 593 $handle->push_write ("request 1\015\012");
328 594
329 # we expect "ERROR" or "OK" as response, so push a line read 595 # we expect "ERROR" or "OK" as response, so push a line read
330 $handle->push_read_line (sub { 596 $handle->push_read (line => sub {
331 # if we got an "OK", we have to _prepend_ another line, 597 # if we got an "OK", we have to _prepend_ another line,
332 # so it will be read before the second request reads its 64 bytes 598 # so it will be read before the second request reads its 64 bytes
333 # which are already in the queue when this callback is called 599 # which are already in the queue when this callback is called
334 # we don't do this in case we got an error 600 # we don't do this in case we got an error
335 if ($_[1] eq "OK") { 601 if ($_[1] eq "OK") {
336 $_[0]->unshift_read_line (sub { 602 $_[0]->unshift_read (line => sub {
337 my $response = $_[1]; 603 my $response = $_[1];
338 ... 604 ...
339 }); 605 });
340 } 606 }
341 }); 607 });
342 608
343 # request two 609 # request two
344 $handle->push_write ("request 2\015\012"); 610 $handle->push_write ("request 2\015\012");
345 611
346 # simply read 64 bytes, always 612 # simply read 64 bytes, always
347 $handle->push_read_chunk (64, sub { 613 $handle->push_read (chunk => 64, sub {
348 my $response = $_[1]; 614 my $response = $_[1];
349 ... 615 ...
350 }); 616 });
351 617
352=over 4 618=over 4
353 619
620=cut
621
354sub _drain_rbuf { 622sub _drain_rbuf {
355 my ($self) = @_; 623 my ($self) = @_;
356 624
625 if (
626 defined $self->{rbuf_max}
627 && $self->{rbuf_max} < length $self->{rbuf}
628 ) {
629 return $self->_error (&Errno::ENOSPC, 1);
630 }
631
357 return if exists $self->{in_drain}; 632 return if $self->{in_drain};
358 local $self->{in_drain} = 1; 633 local $self->{in_drain} = 1;
359 634
360 while (my $len = length $self->{rbuf}) { 635 while (my $len = length $self->{rbuf}) {
361 no strict 'refs'; 636 no strict 'refs';
362 if (@{ $self->{queue} }) { 637 if (my $cb = shift @{ $self->{_queue} }) {
363 if ($self->{queue}[0]($self)) { 638 unless ($cb->($self)) {
364 shift @{ $self->{queue} };
365 } elsif ($self->{eof}) { 639 if ($self->{_eof}) {
366 # no progress can be made (not enough data and no data forthcoming) 640 # no progress can be made (not enough data and no data forthcoming)
367 $! = &Errno::EPIPE; return $self->error; 641 return $self->_error (&Errno::EPIPE, 1);
368 } else { 642 }
643
644 unshift @{ $self->{_queue} }, $cb;
369 return; 645 last;
370 } 646 }
371 } elsif ($self->{on_read}) { 647 } elsif ($self->{on_read}) {
372 $self->{on_read}($self); 648 $self->{on_read}($self);
373 649
374 if ( 650 if (
375 $self->{eof} # if no further data will arrive
376 && $len == length $self->{rbuf} # and no data has been consumed 651 $len == length $self->{rbuf} # if no data has been consumed
377 && !@{ $self->{queue} } # and the queue is still empty 652 && !@{ $self->{_queue} } # and the queue is still empty
378 && $self->{on_read} # and we still want to read data 653 && $self->{on_read} # but we still have on_read
379 ) { 654 ) {
655 # no further data will arrive
380 # then no progress can be made 656 # so no progress can be made
381 $! = &Errno::EPIPE; return $self->error; 657 return $self->_error (&Errno::EPIPE, 1)
658 if $self->{_eof};
659
660 last; # more data might arrive
382 } 661 }
383 } else { 662 } else {
384 # read side becomes idle 663 # read side becomes idle
385 delete $self->{rw}; 664 delete $self->{_rw};
386 return; 665 last;
387 } 666 }
388 } 667 }
389 668
390 if ($self->{eof}) {
391 $self->_shutdown;
392 $self->{on_eof}($self); 669 $self->{on_eof}($self)
670 if $self->{_eof} && $self->{on_eof};
671
672 # may need to restart read watcher
673 unless ($self->{_rw}) {
674 $self->start_read
675 if $self->{on_read} || @{ $self->{_queue} };
393 } 676 }
394} 677}
395 678
396=item $handle->on_read ($cb) 679=item $handle->on_read ($cb)
397 680
403 686
404sub on_read { 687sub on_read {
405 my ($self, $cb) = @_; 688 my ($self, $cb) = @_;
406 689
407 $self->{on_read} = $cb; 690 $self->{on_read} = $cb;
408
409 unless ($self->{rw} || $self->{eof}) {
410 Scalar::Util::weaken $self;
411
412 $self->{rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub {
413 my $len = sysread $self->{fh}, $self->{rbuf}, $self->{read_size} || 8192, length $self->{rbuf};
414
415 if ($len > 0) {
416 if (exists $self->{rbuf_max}) {
417 if ($self->{rbuf_max} < length $self->{rbuf}) {
418 $! = &Errno::ENOSPC; return $self->error;
419 }
420 }
421
422 } elsif (defined $len) {
423 $self->{eof} = 1;
424 delete $self->{rw};
425
426 } elsif ($! != EAGAIN && $! != EINTR) {
427 return $self->error;
428 }
429
430 $self->_drain_rbuf;
431 });
432 }
433} 691}
434 692
435=item $handle->rbuf 693=item $handle->rbuf
436 694
437Returns the read buffer (as a modifiable lvalue). 695Returns the read buffer (as a modifiable lvalue).
456Append the given callback to the end of the queue (C<push_read>) or 714Append the given callback to the end of the queue (C<push_read>) or
457prepend it (C<unshift_read>). 715prepend it (C<unshift_read>).
458 716
459The callback is called each time some additional read data arrives. 717The callback is called each time some additional read data arrives.
460 718
461It must check wether enough data is in the read buffer already. 719It must check whether enough data is in the read buffer already.
462 720
463If not enough data is available, it must return the empty list or a false 721If not enough data is available, it must return the empty list or a false
464value, in which case it will be called repeatedly until enough data is 722value, in which case it will be called repeatedly until enough data is
465available (or an error condition is detected). 723available (or an error condition is detected).
466 724
468interested in (which can be none at all) and return a true value. After returning 726interested in (which can be none at all) and return a true value. After returning
469true, it will be removed from the queue. 727true, it will be removed from the queue.
470 728
471=cut 729=cut
472 730
731our %RH;
732
733sub register_read_type($$) {
734 $RH{$_[0]} = $_[1];
735}
736
473sub push_read { 737sub push_read {
474 my ($self, $cb) = @_; 738 my $self = shift;
739 my $cb = pop;
475 740
741 if (@_) {
742 my $type = shift;
743
744 $cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_read")
745 ->($self, $cb, @_);
746 }
747
476 push @{ $self->{queue} }, $cb; 748 push @{ $self->{_queue} }, $cb;
477 $self->_drain_rbuf; 749 $self->_drain_rbuf;
478} 750}
479 751
480sub unshift_read { 752sub unshift_read {
481 my ($self, $cb) = @_; 753 my $self = shift;
754 my $cb = pop;
482 755
756 if (@_) {
757 my $type = shift;
758
759 $cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::unshift_read")
760 ->($self, $cb, @_);
761 }
762
763
483 push @{ $self->{queue} }, $cb; 764 unshift @{ $self->{_queue} }, $cb;
484 $self->_drain_rbuf; 765 $self->_drain_rbuf;
485} 766}
486 767
487=item $handle->push_read_chunk ($len, $cb->($self, $data)) 768=item $handle->push_read (type => @args, $cb)
488 769
489=item $handle->unshift_read_chunk ($len, $cb->($self, $data)) 770=item $handle->unshift_read (type => @args, $cb)
490 771
491Append the given callback to the end of the queue (C<push_read_chunk>) or 772Instead of providing a callback that parses the data itself you can chose
492prepend it (C<unshift_read_chunk>). 773between a number of predefined parsing formats, for chunks of data, lines
774etc.
493 775
494The callback will be called only once C<$len> bytes have been read, and 776Predefined types are (if you have ideas for additional types, feel free to
495these C<$len> bytes will be passed to the callback. 777drop by and tell us):
496 778
497=cut 779=over 4
498 780
499sub _read_chunk($$) { 781=item chunk => $octets, $cb->($handle, $data)
500 my ($len, $cb) = @_; 782
783Invoke the callback only once C<$octets> bytes have been read. Pass the
784data read to the callback. The callback will never be called with less
785data.
786
787Example: read 2 bytes.
788
789 $handle->push_read (chunk => 2, sub {
790 warn "yay ", unpack "H*", $_[1];
791 });
792
793=cut
794
795register_read_type chunk => sub {
796 my ($self, $cb, $len) = @_;
501 797
502 sub { 798 sub {
503 $len <= length $_[0]{rbuf} or return; 799 $len <= length $_[0]{rbuf} or return;
504 $cb->($_[0], substr $_[0]{rbuf}, 0, $len, ""); 800 $cb->($_[0], substr $_[0]{rbuf}, 0, $len, "");
505 1 801 1
506 } 802 }
507} 803};
508 804
805# compatibility with older API
509sub push_read_chunk { 806sub push_read_chunk {
510 my ($self, $len, $cb) = @_; 807 $_[0]->push_read (chunk => $_[1], $_[2]);
511
512 $self->push_read (_read_chunk $len, $cb);
513} 808}
514
515 809
516sub unshift_read_chunk { 810sub unshift_read_chunk {
517 my ($self, $len, $cb) = @_; 811 $_[0]->unshift_read (chunk => $_[1], $_[2]);
518
519 $self->unshift_read (_read_chunk $len, $cb);
520} 812}
521 813
522=item $handle->push_read_line ([$eol, ]$cb->($self, $line, $eol)) 814=item line => [$eol, ]$cb->($handle, $line, $eol)
523
524=item $handle->unshift_read_line ([$eol, ]$cb->($self, $line, $eol))
525
526Append the given callback to the end of the queue (C<push_read_line>) or
527prepend it (C<unshift_read_line>).
528 815
529The callback will be called only once a full line (including the end of 816The callback will be called only once a full line (including the end of
530line marker, C<$eol>) has been read. This line (excluding the end of line 817line marker, C<$eol>) has been read. This line (excluding the end of line
531marker) will be passed to the callback as second argument (C<$line>), and 818marker) will be passed to the callback as second argument (C<$line>), and
532the end of line marker as the third argument (C<$eol>). 819the end of line marker as the third argument (C<$eol>).
543Partial lines at the end of the stream will never be returned, as they are 830Partial lines at the end of the stream will never be returned, as they are
544not marked by the end of line marker. 831not marked by the end of line marker.
545 832
546=cut 833=cut
547 834
548sub _read_line($$) { 835register_read_type line => sub {
549 my $cb = pop; 836 my ($self, $cb, $eol) = @_;
550 my $eol = @_ ? shift : qr|(\015?\012)|;
551 my $pos;
552 837
838 $eol = qr|(\015?\012)| if @_ < 3;
553 $eol = qr|(\Q$eol\E)| unless ref $eol; 839 $eol = quotemeta $eol unless ref $eol;
554 $eol = qr|^(.*?)($eol)|; 840 $eol = qr|^(.*?)($eol)|s;
555 841
556 sub { 842 sub {
557 $_[0]{rbuf} =~ s/$eol// or return; 843 $_[0]{rbuf} =~ s/$eol// or return;
558 844
559 $cb->($1, $2); 845 $cb->($_[0], $1, $2);
560 1 846 1
561 } 847 }
562} 848};
563 849
850# compatibility with older API
564sub push_read_line { 851sub push_read_line {
565 my $self = shift; 852 my $self = shift;
566
567 $self->push_read (&_read_line); 853 $self->push_read (line => @_);
568} 854}
569 855
570sub unshift_read_line { 856sub unshift_read_line {
571 my $self = shift; 857 my $self = shift;
572
573 $self->unshift_read (&_read_line); 858 $self->unshift_read (line => @_);
574} 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 }
877 return;
878 }
879
880 my $len = $1;
881
882 $self->unshift_read (chunk => $len, sub {
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 });
891 });
892
893 1
894 }
895};
896
897=item regex => $accept[, $reject[, $skip], $cb->($handle, $data)
898
899Makes a regex match against the regex object C<$accept> and returns
900everything up to and including the match.
901
902Example: read a single line terminated by '\n'.
903
904 $handle->push_read (regex => qr<\n>, sub { ... });
905
906If C<$reject> is given and not undef, then it determines when the data is
907to be rejected: it is matched against the data when the C<$accept> regex
908does not match and generates an C<EBADMSG> error when it matches. This is
909useful to quickly reject wrong data (to avoid waiting for a timeout or a
910receive buffer overflow).
911
912Example: expect a single decimal number followed by whitespace, reject
913anything else (not the use of an anchor).
914
915 $handle->push_read (regex => qr<^[0-9]+\s>, qr<[^0-9]>, sub { ... });
916
917If C<$skip> is given and not C<undef>, then it will be matched against
918the receive buffer when neither C<$accept> nor C<$reject> match,
919and everything preceding and including the match will be accepted
920unconditionally. This is useful to skip large amounts of data that you
921know cannot be matched, so that the C<$accept> or C<$reject> regex do not
922have to start matching from the beginning. This is purely an optimisation
923and is usually worth only when you expect more than a few kilobytes.
924
925Example: expect a http header, which ends at C<\015\012\015\012>. Since we
926expect the header to be very large (it isn't in practise, but...), we use
927a skip regex to skip initial portions. The skip regex is tricky in that
928it only accepts something not ending in either \015 or \012, as these are
929required for the accept regex.
930
931 $handle->push_read (regex =>
932 qr<\015\012\015\012>,
933 undef, # no reject
934 qr<^.*[^\015\012]>,
935 sub { ... });
936
937=cut
938
939register_read_type regex => sub {
940 my ($self, $cb, $accept, $reject, $skip) = @_;
941
942 my $data;
943 my $rbuf = \$self->{rbuf};
944
945 sub {
946 # accept
947 if ($$rbuf =~ $accept) {
948 $data .= substr $$rbuf, 0, $+[0], "";
949 $cb->($self, $data);
950 return 1;
951 }
952
953 # reject
954 if ($reject && $$rbuf =~ $reject) {
955 $self->_error (&Errno::EBADMSG);
956 }
957
958 # skip
959 if ($skip && $$rbuf =~ $skip) {
960 $data .= substr $$rbuf, 0, $+[0], "";
961 }
962
963 ()
964 }
965};
966
967=item json => $cb->($handle, $hash_or_arrayref)
968
969Reads a JSON object or array, decodes it and passes it to the callback.
970
971If 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.
973
974This read type uses the incremental parser available with JSON version
9752.09 (and JSON::XS version 2.2) and above. You have to provide a
976dependency on your own: this module will load the JSON module, but
977AnyEvent does not depend on it itself.
978
979Since JSON texts are fully self-delimiting, the C<json> read and write
980types are an ideal simple RPC protocol: just exchange JSON datagrams. See
981the C<json> write type description, above, for an actual example.
982
983=cut
984
985register_read_type json => sub {
986 my ($self, $cb, $accept, $reject, $skip) = @_;
987
988 require JSON;
989
990 my $data;
991 my $rbuf = \$self->{rbuf};
992
993 my $json = $self->{json} ||= JSON->new->utf8;
994
995 sub {
996 my $ref = $json->incr_parse ($self->{rbuf});
997
998 if ($ref) {
999 $self->{rbuf} = $json->incr_text;
1000 $json->incr_text = "";
1001 $cb->($self, $ref);
1002
1003 1
1004 } else {
1005 $self->{rbuf} = "";
1006 ()
1007 }
1008 }
1009};
575 1010
576=back 1011=back
577 1012
1013=item AnyEvent::Handle::register_read_type type => $coderef->($handle, $cb, @args)
1014
1015This function (not method) lets you add your own types to C<push_read>.
1016
1017Whenever the given C<type> is used, C<push_read> will invoke the code
1018reference with the handle object, the callback and the remaining
1019arguments.
1020
1021The code reference is supposed to return a callback (usually a closure)
1022that works as a plain read callback (see C<< ->push_read ($cb) >>).
1023
1024It should invoke the passed callback when it is done reading (remember to
1025pass C<$handle> as first argument as all other callbacks do that).
1026
1027Note that this is a function, and all types registered this way will be
1028global, so try to use unique names.
1029
1030For examples, see the source of this module (F<perldoc -m AnyEvent::Handle>,
1031search for C<register_read_type>)).
1032
1033=item $handle->stop_read
1034
1035=item $handle->start_read
1036
1037In 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
1039any queued callbacks will be executed then. To start reading again, call
1040C<start_read>.
1041
1042Note 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
1044will automatically C<stop_read> for you when neither C<on_read> is set nor
1045there are any read requests in the queue.
1046
1047=cut
1048
1049sub stop_read {
1050 my ($self) = @_;
1051
1052 delete $self->{_rw};
1053}
1054
1055sub start_read {
1056 my ($self) = @_;
1057
1058 unless ($self->{_rw} || $self->{_eof}) {
1059 Scalar::Util::weaken $self;
1060
1061 $self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub {
1062 my $rbuf = $self->{filter_r} ? \my $buf : \$self->{rbuf};
1063 my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf;
1064
1065 if ($len > 0) {
1066 $self->{_activity} = AnyEvent->now;
1067
1068 $self->{filter_r}
1069 ? $self->{filter_r}($self, $rbuf)
1070 : $self->_drain_rbuf;
1071
1072 } elsif (defined $len) {
1073 delete $self->{_rw};
1074 $self->{_eof} = 1;
1075 $self->_drain_rbuf;
1076
1077 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
1078 return $self->_error ($!, 1);
1079 }
1080 });
1081 }
1082}
1083
1084sub _dotls {
1085 my ($self) = @_;
1086
1087 my $buf;
1088
1089 if (length $self->{_tls_wbuf}) {
1090 while ((my $len = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) {
1091 substr $self->{_tls_wbuf}, 0, $len, "";
1092 }
1093 }
1094
1095 if (length ($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}))) {
1101 if (length $buf) {
1102 $self->{rbuf} .= $buf;
1103 $self->_drain_rbuf;
1104 } else {
1105 # let's treat SSL-eof as we treat normal EOF
1106 $self->{_eof} = 1;
1107 $self->_shutdown;
1108 return;
1109 }
1110 }
1111
1112 my $err = Net::SSLeay::get_error ($self->{tls}, -1);
1113
1114 if ($err!= Net::SSLeay::ERROR_WANT_READ ()) {
1115 if ($err == Net::SSLeay::ERROR_SYSCALL ()) {
1116 return $self->_error ($!, 1);
1117 } elsif ($err == Net::SSLeay::ERROR_SSL ()) {
1118 return $self->_error (&Errno::EIO, 1);
1119 }
1120
1121 # all others are fine for our purposes
1122 }
1123}
1124
1125=item $handle->starttls ($tls[, $tls_ctx])
1126
1127Instead of starting TLS negotiation immediately when the AnyEvent::Handle
1128object is created, you can also do that at a later time by calling
1129C<starttls>.
1130
1131The first argument is the same as the C<tls> constructor argument (either
1132C<"connect">, C<"accept"> or an existing Net::SSLeay object).
1133
1134The second argument is the optional C<Net::SSLeay::CTX> object that is
1135used when AnyEvent::Handle has to create its own TLS connection object.
1136
1137The TLS connection object will end up in C<< $handle->{tls} >> after this
1138call and can be used or changed to your liking. Note that the handshake
1139might have already started when this function returns.
1140
1141=cut
1142
1143sub starttls {
1144 my ($self, $ssl, $ctx) = @_;
1145
1146 $self->stoptls;
1147
1148 if ($ssl eq "accept") {
1149 $ssl = Net::SSLeay::new ($ctx || TLS_CTX ());
1150 Net::SSLeay::set_accept_state ($ssl);
1151 } elsif ($ssl eq "connect") {
1152 $ssl = Net::SSLeay::new ($ctx || TLS_CTX ());
1153 Net::SSLeay::set_connect_state ($ssl);
1154 }
1155
1156 $self->{tls} = $ssl;
1157
1158 # basically, this is deep magic (because SSL_read should have the same issues)
1159 # but the openssl maintainers basically said: "trust us, it just works".
1160 # (unfortunately, we have to hardcode constants because the abysmally misdesigned
1161 # and mismaintained ssleay-module doesn't even offer them).
1162 # http://www.mail-archive.com/openssl-dev@openssl.org/msg22420.html
1163 Net::SSLeay::CTX_set_mode ($self->{tls},
1164 (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)
1165 | (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2));
1166
1167 $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1168 $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
1169
1170 Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio});
1171
1172 $self->{filter_w} = sub {
1173 $_[0]{_tls_wbuf} .= ${$_[1]};
1174 &_dotls;
1175 };
1176 $self->{filter_r} = sub {
1177 Net::SSLeay::BIO_write ($_[0]{_rbio}, ${$_[1]});
1178 &_dotls;
1179 };
1180}
1181
1182=item $handle->stoptls
1183
1184Destroys the SSL connection, if any. Partial read or write data will be
1185lost.
1186
1187=cut
1188
1189sub stoptls {
1190 my ($self) = @_;
1191
1192 Net::SSLeay::free (delete $self->{tls}) if $self->{tls};
1193
1194 delete $self->{_rbio};
1195 delete $self->{_wbio};
1196 delete $self->{_tls_wbuf};
1197 delete $self->{filter_r};
1198 delete $self->{filter_w};
1199}
1200
1201sub DESTROY {
1202 my $self = shift;
1203
1204 $self->stoptls;
1205}
1206
1207=item AnyEvent::Handle::TLS_CTX
1208
1209This function creates and returns the Net::SSLeay::CTX object used by
1210default for TLS mode.
1211
1212The context is created like this:
1213
1214 Net::SSLeay::load_error_strings;
1215 Net::SSLeay::SSLeay_add_ssl_algorithms;
1216 Net::SSLeay::randomize;
1217
1218 my $CTX = Net::SSLeay::CTX_new;
1219
1220 Net::SSLeay::CTX_set_options $CTX, Net::SSLeay::OP_ALL
1221
1222=cut
1223
1224our $TLS_CTX;
1225
1226sub TLS_CTX() {
1227 $TLS_CTX || do {
1228 require Net::SSLeay;
1229
1230 Net::SSLeay::load_error_strings ();
1231 Net::SSLeay::SSLeay_add_ssl_algorithms ();
1232 Net::SSLeay::randomize ();
1233
1234 $TLS_CTX = Net::SSLeay::CTX_new ();
1235
1236 Net::SSLeay::CTX_set_options ($TLS_CTX, Net::SSLeay::OP_ALL ());
1237
1238 $TLS_CTX
1239 }
1240}
1241
1242=back
1243
1244=head1 SUBCLASSING AnyEvent::Handle
1245
1246In many cases, you might want to subclass AnyEvent::Handle.
1247
1248To make this easier, a given version of AnyEvent::Handle uses these
1249conventions:
1250
1251=over 4
1252
1253=item * all constructor arguments become object members.
1254
1255At 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
1257mutated later on (for example C<tls> will hold the TLS connection object).
1258
1259=item * other object member names are prefixed with an C<_>.
1260
1261All object members not explicitly documented (internal use) are prefixed
1262with an underscore character, so the remaining non-C<_>-namespace is free
1263for use for subclasses.
1264
1265=item * all members not documented here and not prefixed with an underscore
1266are free to use in subclasses.
1267
1268Of course, new versions of AnyEvent::Handle may introduce more "public"
1269member variables, but thats just life, at least it is documented.
1270
1271=back
1272
578=head1 AUTHOR 1273=head1 AUTHOR
579 1274
580Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>. 1275Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>.
581 1276
582=cut 1277=cut

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