ViewVC Help
View File | Revision Log | Show Annotations | Download File
/cvs/AnyEvent/lib/AnyEvent/Handle.pm
(Generate patch)

Comparing AnyEvent/lib/AnyEvent/Handle.pm (file contents):
Revision 1.37 by root, Mon May 26 20:02:22 2008 UTC vs.
Revision 1.107 by root, Wed Nov 26 06:40:47 2008 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(WSAWOULDBLOCK); 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 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 = '0.04'; 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
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 => $cb->($self) 82=item on_eof => $cb->($handle)
79 83
80Set the callback to be called on EOF. 84Set the callback to be called when an end-of-file condition is detected,
85i.e. in the case of a socket, when the other side has closed the
86connection cleanly.
81 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
82While not mandatory, it is highly recommended to set an eof callback, 93While not mandatory, it is I<highly> recommended to set an EOF callback,
83otherwise 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
84waiting for data. 95waiting for data.
85 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>.
99
86=item on_error => $cb->($self) 100=item on_error => $cb->($handle, $fatal)
87 101
88This is the fatal error callback, that is called when, well, a fatal error 102This is the error callback, which is called when, well, some error
89occurs, such as not being able to resolve the hostname, failure to connect 103occured, such as not being able to resolve the hostname, failure to
90or a read error. 104connect or a read error.
91 105
92The object will not be in a usable state when this callback has been 106Some errors are fatal (which is indicated by C<$fatal> being true). On
93called. 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
112Non-fatal errors can be retried by simply returning, but it is recommended
113to simply ignore this parameter and instead abondon the handle object
114when this callback is invoked. Examples of non-fatal errors are timeouts
115C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>).
94 116
95On callback entrance, the value of C<$!> contains the operating system 117On callback entrance, the value of C<$!> contains the operating system
96error (or C<ENOSPC>, C<EPIPE> or C<EBADMSG>). 118error (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT> or C<EBADMSG>).
97
98The callbakc should throw an exception. If it returns, then
99AnyEvent::Handle will C<croak> for you.
100 119
101While 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
102you will not be notified of errors otherwise. The default simply calls 121you will not be notified of errors otherwise. The default simply calls
103die. 122C<croak>.
104 123
105=item on_read => $cb->($self) 124=item on_read => $cb->($handle)
106 125
107This sets the default read callback, which is called when data arrives 126This sets the default read callback, which is called when data arrives
108and 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).
109 130
110To 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 >>
111method or access the C<$self->{rbuf}> member directly. 132method or access the C<$handle->{rbuf}> member directly.
112 133
113When an EOF condition is detected then AnyEvent::Handle will first try to 134When an EOF condition is detected then AnyEvent::Handle will first try to
114feed all the remaining data to the queued callbacks and C<on_read> before 135feed all the remaining data to the queued callbacks and C<on_read> before
115calling the C<on_eof> callback. If no progress can be made, then a fatal 136calling the C<on_eof> callback. If no progress can be made, then a fatal
116error will be raised (with C<$!> set to C<EPIPE>). 137error will be raised (with C<$!> set to C<EPIPE>).
117 138
118=item on_drain => $cb->() 139=item on_drain => $cb->($handle)
119 140
120This sets the callback that is called when the write buffer becomes empty 141This sets the callback that is called when the write buffer becomes empty
121(or when the callback is set and the buffer is empty already). 142(or when the callback is set and the buffer is empty already).
122 143
123To append to the write buffer, use the C<< ->push_write >> method. 144To append to the write buffer, use the C<< ->push_write >> method.
124 145
146This callback is useful when you don't want to put all of your write data
147into the queue at once, for example, when you want to write the contents
148of some file to the socket you might not want to read the whole file into
149memory and push it into the queue, but instead only read more data from
150the file when the write queue becomes empty.
151
152=item timeout => $fractional_seconds
153
154If non-zero, then this enables an "inactivity" timeout: whenever this many
155seconds pass without a successful read or write on the underlying file
156handle, the C<on_timeout> callback will be invoked (and if that one is
157missing, a non-fatal C<ETIMEDOUT> error will be raised).
158
159Note that timeout processing is also active when you currently do not have
160any outstanding read or write requests: If you plan to keep the connection
161idle then you should disable the timout temporarily or ignore the timeout
162in the C<on_timeout> callback, in which case AnyEvent::Handle will simply
163restart the timeout.
164
165Zero (the default) disables this timeout.
166
167=item on_timeout => $cb->($handle)
168
169Called whenever the inactivity timeout passes. If you return from this
170callback, then the timeout will be reset as if some activity had happened,
171so this condition is not fatal in any way.
172
125=item rbuf_max => <bytes> 173=item rbuf_max => <bytes>
126 174
127If 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>)
128when 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
129avoid denial-of-service attacks. 177avoid some forms of denial-of-service attacks.
130 178
131For example, a server accepting connections from untrusted sources should 179For example, a server accepting connections from untrusted sources should
132be 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
133(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
134amount 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
135isn't finished). 183isn't finished).
136 184
185=item autocork => <boolean>
186
187When disabled (the default), then C<push_write> will try to immediately
188write the data to the handle, if possible. This avoids having to register
189a write watcher and wait for the next event loop iteration, but can
190be inefficient if you write multiple small chunks (on the wire, this
191disadvantage is usually avoided by your kernel's nagle algorithm, see
192C<no_delay>, but this option can save costly syscalls).
193
194When enabled, then writes will always be queued till the next event loop
195iteration. This is efficient when you do many small writes per iteration,
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.
198
199=item no_delay => <boolean>
200
201When doing small writes on sockets, your operating system kernel might
202wait a bit for more data before actually sending it out. This is called
203the Nagle algorithm, and usually it is beneficial.
204
205In some situations you want as low a delay as possible, which can be
206accomplishd by setting this option to a true value.
207
208The default is your opertaing system's default behaviour (most likely
209enabled), this option explicitly enables or disables it, if possible.
210
137=item read_size => <bytes> 211=item read_size => <bytes>
138 212
139The 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
140on each [loop iteration). Default: C<4096>. 214try to read during each loop iteration, which affects memory
215requirements). Default: C<8192>.
141 216
142=item low_water_mark => <bytes> 217=item low_water_mark => <bytes>
143 218
144Sets 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
145buffer: 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
146considered empty. 221considered empty.
147 222
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
228=item linger => <seconds>
229
230If non-zero (default: C<3600>), then the destructor of the
231AnyEvent::Handle object will check whether there is still outstanding
232write data and will install a watcher that will write this data to the
233socket. No errors will be reported (this mostly matches how the operating
234system treats outstanding data at socket close time).
235
236This will not work for partial TLS data that could not be encoded
237yet. This data will be lost. Calling the C<stoptls> method in time might
238help.
239
148=item tls => "accept" | "connect" | Net::SSLeay::SSL object 240=item tls => "accept" | "connect" | Net::SSLeay::SSL object
149 241
150When this parameter is given, it enables TLS (SSL) mode, that means it 242When this parameter is given, it enables TLS (SSL) mode, that means
151will start making tls handshake and will transparently encrypt/decrypt 243AnyEvent will start a TLS handshake as soon as the conenction has been
152data. 244established and will transparently encrypt/decrypt data afterwards.
153 245
154TLS mode requires Net::SSLeay to be installed (it will be loaded 246TLS mode requires Net::SSLeay to be installed (it will be loaded
155automatically 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.
156 250
157For 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
158connection, use C<connect> mode. 252C<accept>, and for the TLS client side of a connection, use C<connect>
253mode.
159 254
160You can also provide your own TLS connection object, but you have 255You can also provide your own TLS connection object, but you have
161to 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>
162or 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
163AnyEvent::Handle. 258AnyEvent::Handle.
164 259
165See 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.
166 261
167=item tls_ctx => $ssl_ctx 262=item tls_ctx => $ssl_ctx
168 263
169Use 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
170(unless a connection object was specified directly). If this parameter is 265(unless a connection object was specified directly). If this parameter is
171missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>. 266missing, then AnyEvent::Handle will use C<AnyEvent::Handle::TLS_CTX>.
172 267
268=item json => JSON or JSON::XS object
269
270This is the json coder object used by the C<json> read and write types.
271
272If you don't supply it, then AnyEvent::Handle will create and use a
273suitable one (on demand), which will write and expect UTF-8 encoded JSON
274texts.
275
276Note that you are responsible to depend on the JSON module if you want to
277use this functionality, as AnyEvent does not have a dependency itself.
278
173=back 279=back
174 280
175=cut 281=cut
176 282
177sub new { 283sub new {
181 287
182 $self->{fh} or Carp::croak "mandatory argument fh is missing"; 288 $self->{fh} or Carp::croak "mandatory argument fh is missing";
183 289
184 AnyEvent::Util::fh_nonblocking $self->{fh}, 1; 290 AnyEvent::Util::fh_nonblocking $self->{fh}, 1;
185 291
186 if ($self->{tls}) {
187 require Net::SSLeay;
188 $self->starttls (delete $self->{tls}, delete $self->{tls_ctx}); 292 $self->starttls (delete $self->{tls}, delete $self->{tls_ctx})
189 } 293 if $self->{tls};
190 294
191 $self->on_eof (delete $self->{on_eof} ) if $self->{on_eof}; 295 $self->{_activity} = AnyEvent->now;
192 $self->on_error (delete $self->{on_error}) if $self->{on_error}; 296 $self->_timeout;
297
193 $self->on_drain (delete $self->{on_drain}) if $self->{on_drain}; 298 $self->on_drain (delete $self->{on_drain}) if exists $self->{on_drain};
194 $self->on_read (delete $self->{on_read} ) if $self->{on_read}; 299 $self->no_delay (delete $self->{no_delay}) if exists $self->{no_delay};
195 300
196 $self->start_read; 301 $self->start_read
302 if $self->{on_read};
197 303
198 $self 304 $self
199} 305}
200 306
201sub _shutdown { 307sub _shutdown {
202 my ($self) = @_; 308 my ($self) = @_;
203 309
310 delete $self->{_tw};
204 delete $self->{rw}; 311 delete $self->{_rw};
205 delete $self->{ww}; 312 delete $self->{_ww};
206 delete $self->{fh}; 313 delete $self->{fh};
207}
208 314
315 &_freetls;
316
317 delete $self->{on_read};
318 delete $self->{_queue};
319}
320
209sub error { 321sub _error {
210 my ($self) = @_; 322 my ($self, $errno, $fatal) = @_;
211 323
212 {
213 local $!;
214 $self->_shutdown; 324 $self->_shutdown
215 } 325 if $fatal;
216 326
217 $self->{on_error}($self) 327 $! = $errno;
328
218 if $self->{on_error}; 329 if ($self->{on_error}) {
219 330 $self->{on_error}($self, $fatal);
331 } elsif ($self->{fh}) {
220 Carp::croak "AnyEvent::Handle uncaught fatal error: $!"; 332 Carp::croak "AnyEvent::Handle uncaught error: $!";
333 }
221} 334}
222 335
223=item $fh = $handle->fh 336=item $fh = $handle->fh
224 337
225This 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.
226 339
227=cut 340=cut
228 341
229sub fh { $_[0]->{fh} } 342sub fh { $_[0]{fh} }
230 343
231=item $handle->on_error ($cb) 344=item $handle->on_error ($cb)
232 345
233Replace the current C<on_error> callback (see the C<on_error> constructor argument). 346Replace the current C<on_error> callback (see the C<on_error> constructor argument).
234 347
246 359
247sub on_eof { 360sub on_eof {
248 $_[0]{on_eof} = $_[1]; 361 $_[0]{on_eof} = $_[1];
249} 362}
250 363
364=item $handle->on_timeout ($cb)
365
366Replace the current C<on_timeout> callback, or disables the callback (but
367not the timeout) if C<$cb> = C<undef>. See the C<timeout> constructor
368argument and method.
369
370=cut
371
372sub on_timeout {
373 $_[0]{on_timeout} = $_[1];
374}
375
376=item $handle->autocork ($boolean)
377
378Enables or disables the current autocork behaviour (see C<autocork>
379constructor argument). Changes will only take effect on the next write.
380
381=cut
382
383sub autocork {
384 $_[0]{autocork} = $_[1];
385}
386
387=item $handle->no_delay ($boolean)
388
389Enables or disables the C<no_delay> setting (see constructor argument of
390the same name for details).
391
392=cut
393
394sub no_delay {
395 $_[0]{no_delay} = $_[1];
396
397 eval {
398 local $SIG{__DIE__};
399 setsockopt $_[0]{fh}, &Socket::IPPROTO_TCP, &Socket::TCP_NODELAY, int $_[1];
400 };
401}
402
403#############################################################################
404
405=item $handle->timeout ($seconds)
406
407Configures (or disables) the inactivity timeout.
408
409=cut
410
411sub timeout {
412 my ($self, $timeout) = @_;
413
414 $self->{timeout} = $timeout;
415 $self->_timeout;
416}
417
418# reset the timeout watcher, as neccessary
419# also check for time-outs
420sub _timeout {
421 my ($self) = @_;
422
423 if ($self->{timeout}) {
424 my $NOW = AnyEvent->now;
425
426 # when would the timeout trigger?
427 my $after = $self->{_activity} + $self->{timeout} - $NOW;
428
429 # now or in the past already?
430 if ($after <= 0) {
431 $self->{_activity} = $NOW;
432
433 if ($self->{on_timeout}) {
434 $self->{on_timeout}($self);
435 } else {
436 $self->_error (&Errno::ETIMEDOUT);
437 }
438
439 # callback could have changed timeout value, optimise
440 return unless $self->{timeout};
441
442 # calculate new after
443 $after = $self->{timeout};
444 }
445
446 Scalar::Util::weaken $self;
447 return unless $self; # ->error could have destroyed $self
448
449 $self->{_tw} ||= AnyEvent->timer (after => $after, cb => sub {
450 delete $self->{_tw};
451 $self->_timeout;
452 });
453 } else {
454 delete $self->{_tw};
455 }
456}
457
251############################################################################# 458#############################################################################
252 459
253=back 460=back
254 461
255=head2 WRITE QUEUE 462=head2 WRITE QUEUE
276 my ($self, $cb) = @_; 483 my ($self, $cb) = @_;
277 484
278 $self->{on_drain} = $cb; 485 $self->{on_drain} = $cb;
279 486
280 $cb->($self) 487 $cb->($self)
281 if $cb && $self->{low_water_mark} >= length $self->{wbuf}; 488 if $cb && $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf});
282} 489}
283 490
284=item $handle->push_write ($data) 491=item $handle->push_write ($data)
285 492
286Queues 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
290=cut 497=cut
291 498
292sub _drain_wbuf { 499sub _drain_wbuf {
293 my ($self) = @_; 500 my ($self) = @_;
294 501
295 if (!$self->{ww} && length $self->{wbuf}) { 502 if (!$self->{_ww} && length $self->{wbuf}) {
296 503
297 Scalar::Util::weaken $self; 504 Scalar::Util::weaken $self;
298 505
299 my $cb = sub { 506 my $cb = sub {
300 my $len = syswrite $self->{fh}, $self->{wbuf}; 507 my $len = syswrite $self->{fh}, $self->{wbuf};
301 508
302 if ($len >= 0) { 509 if ($len >= 0) {
303 substr $self->{wbuf}, 0, $len, ""; 510 substr $self->{wbuf}, 0, $len, "";
304 511
512 $self->{_activity} = AnyEvent->now;
513
305 $self->{on_drain}($self) 514 $self->{on_drain}($self)
306 if $self->{low_water_mark} >= length $self->{wbuf} 515 if $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf})
307 && $self->{on_drain}; 516 && $self->{on_drain};
308 517
309 delete $self->{ww} unless length $self->{wbuf}; 518 delete $self->{_ww} unless length $self->{wbuf};
310 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAWOULDBLOCK) { 519 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
311 $self->error; 520 $self->_error ($!, 1);
312 } 521 }
313 }; 522 };
314 523
315 # try to write data immediately 524 # try to write data immediately
316 $cb->(); 525 $cb->() unless $self->{autocork};
317 526
318 # if still data left in wbuf, we need to poll 527 # if still data left in wbuf, we need to poll
319 $self->{ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb) 528 $self->{_ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb)
320 if length $self->{wbuf}; 529 if length $self->{wbuf};
321 }; 530 };
322} 531}
323 532
324our %WH; 533our %WH;
335 544
336 @_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write") 545 @_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write")
337 ->($self, @_); 546 ->($self, @_);
338 } 547 }
339 548
340 if ($self->{filter_w}) { 549 if ($self->{tls}) {
341 $self->{filter_w}->($self, \$_[0]); 550 $self->{_tls_wbuf} .= $_[0];
551
552 &_dotls ($self);
342 } else { 553 } else {
343 $self->{wbuf} .= $_[0]; 554 $self->{wbuf} .= $_[0];
344 $self->_drain_wbuf; 555 $self->_drain_wbuf;
345 } 556 }
346} 557}
347 558
348=item $handle->push_write (type => @args) 559=item $handle->push_write (type => @args)
349 560
350=item $handle->unshift_write (type => @args)
351
352Instead of formatting your data yourself, you can also let this module do 561Instead of formatting your data yourself, you can also let this module do
353the job by specifying a type and type-specific arguments. 562the job by specifying a type and type-specific arguments.
354 563
355Predefined types are (if you have ideas for additional types, feel free to 564Predefined types are (if you have ideas for additional types, feel free to
356drop by and tell us): 565drop by and tell us):
360=item netstring => $string 569=item netstring => $string
361 570
362Formats the given value as netstring 571Formats the given value as netstring
363(http://cr.yp.to/proto/netstrings.txt, this is not a recommendation to use them). 572(http://cr.yp.to/proto/netstrings.txt, this is not a recommendation to use them).
364 573
365=back
366
367=cut 574=cut
368 575
369register_write_type netstring => sub { 576register_write_type netstring => sub {
370 my ($self, $string) = @_; 577 my ($self, $string) = @_;
371 578
372 sprintf "%d:%s,", (length $string), $string 579 (length $string) . ":$string,"
373}; 580};
374 581
582=item packstring => $format, $data
583
584An octet string prefixed with an encoded length. The encoding C<$format>
585uses the same format as a Perl C<pack> format, but must specify a single
586integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
587optional C<!>, C<< < >> or C<< > >> modifier).
588
589=cut
590
591register_write_type packstring => sub {
592 my ($self, $format, $string) = @_;
593
594 pack "$format/a*", $string
595};
596
597=item json => $array_or_hashref
598
599Encodes the given hash or array reference into a JSON object. Unless you
600provide your own JSON object, this means it will be encoded to JSON text
601in UTF-8.
602
603JSON objects (and arrays) are self-delimiting, so you can write JSON at
604one end of a handle and read them at the other end without using any
605additional framing.
606
607The generated JSON text is guaranteed not to contain any newlines: While
608this module doesn't need delimiters after or between JSON texts to be
609able to read them, many other languages depend on that.
610
611A simple RPC protocol that interoperates easily with others is to send
612JSON arrays (or objects, although arrays are usually the better choice as
613they mimic how function argument passing works) and a newline after each
614JSON text:
615
616 $handle->push_write (json => ["method", "arg1", "arg2"]); # whatever
617 $handle->push_write ("\012");
618
619An AnyEvent::Handle receiver would simply use the C<json> read type and
620rely on the fact that the newline will be skipped as leading whitespace:
621
622 $handle->push_read (json => sub { my $array = $_[1]; ... });
623
624Other languages could read single lines terminated by a newline and pass
625this line into their JSON decoder of choice.
626
627=cut
628
629register_write_type json => sub {
630 my ($self, $ref) = @_;
631
632 require JSON;
633
634 $self->{json} ? $self->{json}->encode ($ref)
635 : JSON::encode_json ($ref)
636};
637
638=item storable => $reference
639
640Freezes the given reference using L<Storable> and writes it to the
641handle. Uses the C<nfreeze> format.
642
643=cut
644
645register_write_type storable => sub {
646 my ($self, $ref) = @_;
647
648 require Storable;
649
650 pack "w/a*", Storable::nfreeze ($ref)
651};
652
653=back
654
375=item AnyEvent::Handle::register_write_type type => $coderef->($self, @args) 655=item AnyEvent::Handle::register_write_type type => $coderef->($handle, @args)
376 656
377This function (not method) lets you add your own types to C<push_write>. 657This function (not method) lets you add your own types to C<push_write>.
378Whenever the given C<type> is used, C<push_write> will invoke the code 658Whenever the given C<type> is used, C<push_write> will invoke the code
379reference with the handle object and the remaining arguments. 659reference with the handle object and the remaining arguments.
380 660
399ways, the "simple" way, using only C<on_read> and the "complex" way, using 679ways, the "simple" way, using only C<on_read> and the "complex" way, using
400a queue. 680a queue.
401 681
402In the simple case, you just install an C<on_read> callback and whenever 682In the simple case, you just install an C<on_read> callback and whenever
403new data arrives, it will be called. You can then remove some data (if 683new data arrives, it will be called. You can then remove some data (if
404enough is there) from the read buffer (C<< $handle->rbuf >>) if you want 684enough is there) from the read buffer (C<< $handle->rbuf >>). Or you cna
405or not. 685leave the data there if you want to accumulate more (e.g. when only a
686partial message has been received so far).
406 687
407In the more complex case, you want to queue multiple callbacks. In this 688In the more complex case, you want to queue multiple callbacks. In this
408case, AnyEvent::Handle will call the first queued callback each time new 689case, AnyEvent::Handle will call the first queued callback each time new
409data arrives and removes it when it has done its job (see C<push_read>, 690data arrives (also the first time it is queued) and removes it when it has
410below). 691done its job (see C<push_read>, below).
411 692
412This way you can, for example, push three line-reads, followed by reading 693This way you can, for example, push three line-reads, followed by reading
413a chunk of data, and AnyEvent::Handle will execute them in order. 694a chunk of data, and AnyEvent::Handle will execute them in order.
414 695
415Example 1: EPP protocol parser. EPP sends 4 byte length info, followed by 696Example 1: EPP protocol parser. EPP sends 4 byte length info, followed by
416the specified number of bytes which give an XML datagram. 697the specified number of bytes which give an XML datagram.
417 698
418 # in the default state, expect some header bytes 699 # in the default state, expect some header bytes
419 $handle->on_read (sub { 700 $handle->on_read (sub {
420 # some data is here, now queue the length-header-read (4 octets) 701 # some data is here, now queue the length-header-read (4 octets)
421 shift->unshift_read_chunk (4, sub { 702 shift->unshift_read (chunk => 4, sub {
422 # header arrived, decode 703 # header arrived, decode
423 my $len = unpack "N", $_[1]; 704 my $len = unpack "N", $_[1];
424 705
425 # now read the payload 706 # now read the payload
426 shift->unshift_read_chunk ($len, sub { 707 shift->unshift_read (chunk => $len, sub {
427 my $xml = $_[1]; 708 my $xml = $_[1];
428 # handle xml 709 # handle xml
429 }); 710 });
430 }); 711 });
431 }); 712 });
432 713
433Example 2: Implement a client for a protocol that replies either with 714Example 2: Implement a client for a protocol that replies either with "OK"
434"OK" and another line or "ERROR" for one request, and 64 bytes for the 715and another line or "ERROR" for the first request that is sent, and 64
435second request. Due tot he availability of a full queue, we can just 716bytes for the second request. Due to the availability of a queue, we can
436pipeline sending both requests and manipulate the queue as necessary in 717just pipeline sending both requests and manipulate the queue as necessary
437the callbacks: 718in the callbacks.
438 719
439 # request one 720When the first callback is called and sees an "OK" response, it will
721C<unshift> another line-read. This line-read will be queued I<before> the
72264-byte chunk callback.
723
724 # request one, returns either "OK + extra line" or "ERROR"
440 $handle->push_write ("request 1\015\012"); 725 $handle->push_write ("request 1\015\012");
441 726
442 # we expect "ERROR" or "OK" as response, so push a line read 727 # we expect "ERROR" or "OK" as response, so push a line read
443 $handle->push_read_line (sub { 728 $handle->push_read (line => sub {
444 # if we got an "OK", we have to _prepend_ another line, 729 # if we got an "OK", we have to _prepend_ another line,
445 # so it will be read before the second request reads its 64 bytes 730 # so it will be read before the second request reads its 64 bytes
446 # which are already in the queue when this callback is called 731 # which are already in the queue when this callback is called
447 # we don't do this in case we got an error 732 # we don't do this in case we got an error
448 if ($_[1] eq "OK") { 733 if ($_[1] eq "OK") {
449 $_[0]->unshift_read_line (sub { 734 $_[0]->unshift_read (line => sub {
450 my $response = $_[1]; 735 my $response = $_[1];
451 ... 736 ...
452 }); 737 });
453 } 738 }
454 }); 739 });
455 740
456 # request two 741 # request two, simply returns 64 octets
457 $handle->push_write ("request 2\015\012"); 742 $handle->push_write ("request 2\015\012");
458 743
459 # simply read 64 bytes, always 744 # simply read 64 bytes, always
460 $handle->push_read_chunk (64, sub { 745 $handle->push_read (chunk => 64, sub {
461 my $response = $_[1]; 746 my $response = $_[1];
462 ... 747 ...
463 }); 748 });
464 749
465=over 4 750=over 4
466 751
467=cut 752=cut
468 753
469sub _drain_rbuf { 754sub _drain_rbuf {
470 my ($self) = @_; 755 my ($self) = @_;
756
757 local $self->{_in_drain} = 1;
471 758
472 if ( 759 if (
473 defined $self->{rbuf_max} 760 defined $self->{rbuf_max}
474 && $self->{rbuf_max} < length $self->{rbuf} 761 && $self->{rbuf_max} < length $self->{rbuf}
475 ) { 762 ) {
476 $! = &Errno::ENOSPC; 763 $self->_error (&Errno::ENOSPC, 1), return;
477 $self->error;
478 } 764 }
479 765
480 return if $self->{in_drain}; 766 while () {
481 local $self->{in_drain} = 1;
482
483 while (my $len = length $self->{rbuf}) { 767 my $len = length $self->{rbuf};
484 no strict 'refs'; 768
485 if (my $cb = shift @{ $self->{queue} }) { 769 if (my $cb = shift @{ $self->{_queue} }) {
486 unless ($cb->($self)) { 770 unless ($cb->($self)) {
487 if ($self->{eof}) { 771 if ($self->{_eof}) {
488 # no progress can be made (not enough data and no data forthcoming) 772 # no progress can be made (not enough data and no data forthcoming)
489 $! = &Errno::EPIPE; 773 $self->_error (&Errno::EPIPE, 1), return;
490 $self->error;
491 } 774 }
492 775
493 unshift @{ $self->{queue} }, $cb; 776 unshift @{ $self->{_queue} }, $cb;
494 return; 777 last;
495 } 778 }
496 } elsif ($self->{on_read}) { 779 } elsif ($self->{on_read}) {
780 last unless $len;
781
497 $self->{on_read}($self); 782 $self->{on_read}($self);
498 783
499 if ( 784 if (
500 $self->{eof} # if no further data will arrive
501 && $len == length $self->{rbuf} # and no data has been consumed 785 $len == length $self->{rbuf} # if no data has been consumed
502 && !@{ $self->{queue} } # and the queue is still empty 786 && !@{ $self->{_queue} } # and the queue is still empty
503 && $self->{on_read} # and we still want to read data 787 && $self->{on_read} # but we still have on_read
504 ) { 788 ) {
789 # no further data will arrive
505 # then no progress can be made 790 # so no progress can be made
506 $! = &Errno::EPIPE; 791 $self->_error (&Errno::EPIPE, 1), return
507 $self->error; 792 if $self->{_eof};
793
794 last; # more data might arrive
508 } 795 }
509 } else { 796 } else {
510 # read side becomes idle 797 # read side becomes idle
511 delete $self->{rw}; 798 delete $self->{_rw} unless $self->{tls};
512 return; 799 last;
513 } 800 }
514 } 801 }
515 802
516 if ($self->{eof}) { 803 if ($self->{_eof}) {
517 $self->_shutdown; 804 if ($self->{on_eof}) {
518 $self->{on_eof}($self) 805 $self->{on_eof}($self)
519 if $self->{on_eof}; 806 } else {
807 $self->_error (0, 1);
808 }
809 }
810
811 # may need to restart read watcher
812 unless ($self->{_rw}) {
813 $self->start_read
814 if $self->{on_read} || @{ $self->{_queue} };
520 } 815 }
521} 816}
522 817
523=item $handle->on_read ($cb) 818=item $handle->on_read ($cb)
524 819
530 825
531sub on_read { 826sub on_read {
532 my ($self, $cb) = @_; 827 my ($self, $cb) = @_;
533 828
534 $self->{on_read} = $cb; 829 $self->{on_read} = $cb;
830 $self->_drain_rbuf if $cb && !$self->{_in_drain};
535} 831}
536 832
537=item $handle->rbuf 833=item $handle->rbuf
538 834
539Returns the read buffer (as a modifiable lvalue). 835Returns the read buffer (as a modifiable lvalue).
587 883
588 $cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_read") 884 $cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_read")
589 ->($self, $cb, @_); 885 ->($self, $cb, @_);
590 } 886 }
591 887
592 push @{ $self->{queue} }, $cb; 888 push @{ $self->{_queue} }, $cb;
593 $self->_drain_rbuf; 889 $self->_drain_rbuf unless $self->{_in_drain};
594} 890}
595 891
596sub unshift_read { 892sub unshift_read {
597 my $self = shift; 893 my $self = shift;
598 my $cb = pop; 894 my $cb = pop;
603 $cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::unshift_read") 899 $cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::unshift_read")
604 ->($self, $cb, @_); 900 ->($self, $cb, @_);
605 } 901 }
606 902
607 903
608 unshift @{ $self->{queue} }, $cb; 904 unshift @{ $self->{_queue} }, $cb;
609 $self->_drain_rbuf; 905 $self->_drain_rbuf unless $self->{_in_drain};
610} 906}
611 907
612=item $handle->push_read (type => @args, $cb) 908=item $handle->push_read (type => @args, $cb)
613 909
614=item $handle->unshift_read (type => @args, $cb) 910=item $handle->unshift_read (type => @args, $cb)
620Predefined types are (if you have ideas for additional types, feel free to 916Predefined types are (if you have ideas for additional types, feel free to
621drop by and tell us): 917drop by and tell us):
622 918
623=over 4 919=over 4
624 920
625=item chunk => $octets, $cb->($self, $data) 921=item chunk => $octets, $cb->($handle, $data)
626 922
627Invoke the callback only once C<$octets> bytes have been read. Pass the 923Invoke the callback only once C<$octets> bytes have been read. Pass the
628data read to the callback. The callback will never be called with less 924data read to the callback. The callback will never be called with less
629data. 925data.
630 926
644 $cb->($_[0], substr $_[0]{rbuf}, 0, $len, ""); 940 $cb->($_[0], substr $_[0]{rbuf}, 0, $len, "");
645 1 941 1
646 } 942 }
647}; 943};
648 944
649# compatibility with older API
650sub push_read_chunk {
651 $_[0]->push_read (chunk => $_[1], $_[2]);
652}
653
654sub unshift_read_chunk {
655 $_[0]->unshift_read (chunk => $_[1], $_[2]);
656}
657
658=item line => [$eol, ]$cb->($self, $line, $eol) 945=item line => [$eol, ]$cb->($handle, $line, $eol)
659 946
660The callback will be called only once a full line (including the end of 947The callback will be called only once a full line (including the end of
661line marker, C<$eol>) has been read. This line (excluding the end of line 948line marker, C<$eol>) has been read. This line (excluding the end of line
662marker) will be passed to the callback as second argument (C<$line>), and 949marker) will be passed to the callback as second argument (C<$line>), and
663the end of line marker as the third argument (C<$eol>). 950the end of line marker as the third argument (C<$eol>).
677=cut 964=cut
678 965
679register_read_type line => sub { 966register_read_type line => sub {
680 my ($self, $cb, $eol) = @_; 967 my ($self, $cb, $eol) = @_;
681 968
682 $eol = qr|(\015?\012)| if @_ < 3; 969 if (@_ < 3) {
970 # this is more than twice as fast as the generic code below
971 sub {
972 $_[0]{rbuf} =~ s/^([^\015\012]*)(\015?\012)// or return;
973
974 $cb->($_[0], $1, $2);
975 1
976 }
977 } else {
683 $eol = quotemeta $eol unless ref $eol; 978 $eol = quotemeta $eol unless ref $eol;
684 $eol = qr|^(.*?)($eol)|s; 979 $eol = qr|^(.*?)($eol)|s;
685 980
686 sub { 981 sub {
687 $_[0]{rbuf} =~ s/$eol// or return; 982 $_[0]{rbuf} =~ s/$eol// or return;
688 983
689 $cb->($_[0], $1, $2); 984 $cb->($_[0], $1, $2);
985 1
690 1 986 }
691 } 987 }
692}; 988};
693 989
694# compatibility with older API
695sub push_read_line {
696 my $self = shift;
697 $self->push_read (line => @_);
698}
699
700sub unshift_read_line {
701 my $self = shift;
702 $self->unshift_read (line => @_);
703}
704
705=item netstring => $cb->($string)
706
707A netstring (http://cr.yp.to/proto/netstrings.txt, this is not an endorsement).
708
709Throws an error with C<$!> set to EBADMSG on format violations.
710
711=cut
712
713register_read_type netstring => sub {
714 my ($self, $cb) = @_;
715
716 sub {
717 unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
718 if ($_[0]{rbuf} =~ /[^0-9]/) {
719 $! = &Errno::EBADMSG;
720 $self->error;
721 }
722 return;
723 }
724
725 my $len = $1;
726
727 $self->unshift_read (chunk => $len, sub {
728 my $string = $_[1];
729 $_[0]->unshift_read (chunk => 1, sub {
730 if ($_[1] eq ",") {
731 $cb->($_[0], $string);
732 } else {
733 $! = &Errno::EBADMSG;
734 $self->error;
735 }
736 });
737 });
738
739 1
740 }
741};
742
743=item regex => $accept[, $reject[, $skip], $cb->($data) 990=item regex => $accept[, $reject[, $skip], $cb->($handle, $data)
744 991
745Makes a regex match against the regex object C<$accept> and returns 992Makes a regex match against the regex object C<$accept> and returns
746everything up to and including the match. 993everything up to and including the match.
747 994
748Example: read a single line terminated by '\n'. 995Example: read a single line terminated by '\n'.
796 return 1; 1043 return 1;
797 } 1044 }
798 1045
799 # reject 1046 # reject
800 if ($reject && $$rbuf =~ $reject) { 1047 if ($reject && $$rbuf =~ $reject) {
801 $! = &Errno::EBADMSG; 1048 $self->_error (&Errno::EBADMSG);
802 $self->error;
803 } 1049 }
804 1050
805 # skip 1051 # skip
806 if ($skip && $$rbuf =~ $skip) { 1052 if ($skip && $$rbuf =~ $skip) {
807 $data .= substr $$rbuf, 0, $+[0], ""; 1053 $data .= substr $$rbuf, 0, $+[0], "";
809 1055
810 () 1056 ()
811 } 1057 }
812}; 1058};
813 1059
1060=item netstring => $cb->($handle, $string)
1061
1062A netstring (http://cr.yp.to/proto/netstrings.txt, this is not an endorsement).
1063
1064Throws an error with C<$!> set to EBADMSG on format violations.
1065
1066=cut
1067
1068register_read_type netstring => sub {
1069 my ($self, $cb) = @_;
1070
1071 sub {
1072 unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) {
1073 if ($_[0]{rbuf} =~ /[^0-9]/) {
1074 $self->_error (&Errno::EBADMSG);
1075 }
1076 return;
1077 }
1078
1079 my $len = $1;
1080
1081 $self->unshift_read (chunk => $len, sub {
1082 my $string = $_[1];
1083 $_[0]->unshift_read (chunk => 1, sub {
1084 if ($_[1] eq ",") {
1085 $cb->($_[0], $string);
1086 } else {
1087 $self->_error (&Errno::EBADMSG);
1088 }
1089 });
1090 });
1091
1092 1
1093 }
1094};
1095
1096=item packstring => $format, $cb->($handle, $string)
1097
1098An octet string prefixed with an encoded length. The encoding C<$format>
1099uses the same format as a Perl C<pack> format, but must specify a single
1100integer only (only one of C<cCsSlLqQiInNvVjJw> is allowed, plus an
1101optional C<!>, C<< < >> or C<< > >> modifier).
1102
1103For example, DNS over TCP uses a prefix of C<n> (2 octet network order),
1104EPP uses a prefix of C<N> (4 octtes).
1105
1106Example: read a block of data prefixed by its length in BER-encoded
1107format (very efficient).
1108
1109 $handle->push_read (packstring => "w", sub {
1110 my ($handle, $data) = @_;
1111 });
1112
1113=cut
1114
1115register_read_type packstring => sub {
1116 my ($self, $cb, $format) = @_;
1117
1118 sub {
1119 # when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
1120 defined (my $len = eval { unpack $format, $_[0]{rbuf} })
1121 or return;
1122
1123 $format = length pack $format, $len;
1124
1125 # bypass unshift if we already have the remaining chunk
1126 if ($format + $len <= length $_[0]{rbuf}) {
1127 my $data = substr $_[0]{rbuf}, $format, $len;
1128 substr $_[0]{rbuf}, 0, $format + $len, "";
1129 $cb->($_[0], $data);
1130 } else {
1131 # remove prefix
1132 substr $_[0]{rbuf}, 0, $format, "";
1133
1134 # read remaining chunk
1135 $_[0]->unshift_read (chunk => $len, $cb);
1136 }
1137
1138 1
1139 }
1140};
1141
1142=item json => $cb->($handle, $hash_or_arrayref)
1143
1144Reads a JSON object or array, decodes it and passes it to the callback.
1145
1146If a C<json> object was passed to the constructor, then that will be used
1147for the final decode, otherwise it will create a JSON coder expecting UTF-8.
1148
1149This read type uses the incremental parser available with JSON version
11502.09 (and JSON::XS version 2.2) and above. You have to provide a
1151dependency on your own: this module will load the JSON module, but
1152AnyEvent does not depend on it itself.
1153
1154Since JSON texts are fully self-delimiting, the C<json> read and write
1155types are an ideal simple RPC protocol: just exchange JSON datagrams. See
1156the C<json> write type description, above, for an actual example.
1157
1158=cut
1159
1160register_read_type json => sub {
1161 my ($self, $cb) = @_;
1162
1163 require JSON;
1164
1165 my $data;
1166 my $rbuf = \$self->{rbuf};
1167
1168 my $json = $self->{json} ||= JSON->new->utf8;
1169
1170 sub {
1171 my $ref = $json->incr_parse ($self->{rbuf});
1172
1173 if ($ref) {
1174 $self->{rbuf} = $json->incr_text;
1175 $json->incr_text = "";
1176 $cb->($self, $ref);
1177
1178 1
1179 } else {
1180 $self->{rbuf} = "";
1181 ()
1182 }
1183 }
1184};
1185
1186=item storable => $cb->($handle, $ref)
1187
1188Deserialises a L<Storable> frozen representation as written by the
1189C<storable> write type (BER-encoded length prefix followed by nfreeze'd
1190data).
1191
1192Raises C<EBADMSG> error if the data could not be decoded.
1193
1194=cut
1195
1196register_read_type storable => sub {
1197 my ($self, $cb) = @_;
1198
1199 require Storable;
1200
1201 sub {
1202 # when we can use 5.10 we can use ".", but for 5.8 we use the re-pack method
1203 defined (my $len = eval { unpack "w", $_[0]{rbuf} })
1204 or return;
1205
1206 my $format = length pack "w", $len;
1207
1208 # bypass unshift if we already have the remaining chunk
1209 if ($format + $len <= length $_[0]{rbuf}) {
1210 my $data = substr $_[0]{rbuf}, $format, $len;
1211 substr $_[0]{rbuf}, 0, $format + $len, "";
1212 $cb->($_[0], Storable::thaw ($data));
1213 } else {
1214 # remove prefix
1215 substr $_[0]{rbuf}, 0, $format, "";
1216
1217 # read remaining chunk
1218 $_[0]->unshift_read (chunk => $len, sub {
1219 if (my $ref = eval { Storable::thaw ($_[1]) }) {
1220 $cb->($_[0], $ref);
1221 } else {
1222 $self->_error (&Errno::EBADMSG);
1223 }
1224 });
1225 }
1226
1227 1
1228 }
1229};
1230
814=back 1231=back
815 1232
816=item AnyEvent::Handle::register_read_type type => $coderef->($self, $cb, @args) 1233=item AnyEvent::Handle::register_read_type type => $coderef->($handle, $cb, @args)
817 1234
818This function (not method) lets you add your own types to C<push_read>. 1235This function (not method) lets you add your own types to C<push_read>.
819 1236
820Whenever the given C<type> is used, C<push_read> will invoke the code 1237Whenever the given C<type> is used, C<push_read> will invoke the code
821reference with the handle object, the callback and the remaining 1238reference with the handle object, the callback and the remaining
823 1240
824The code reference is supposed to return a callback (usually a closure) 1241The code reference is supposed to return a callback (usually a closure)
825that works as a plain read callback (see C<< ->push_read ($cb) >>). 1242that works as a plain read callback (see C<< ->push_read ($cb) >>).
826 1243
827It should invoke the passed callback when it is done reading (remember to 1244It should invoke the passed callback when it is done reading (remember to
828pass C<$self> as first argument as all other callbacks do that). 1245pass C<$handle> as first argument as all other callbacks do that).
829 1246
830Note that this is a function, and all types registered this way will be 1247Note that this is a function, and all types registered this way will be
831global, so try to use unique names. 1248global, so try to use unique names.
832 1249
833For examples, see the source of this module (F<perldoc -m AnyEvent::Handle>, 1250For examples, see the source of this module (F<perldoc -m AnyEvent::Handle>,
836=item $handle->stop_read 1253=item $handle->stop_read
837 1254
838=item $handle->start_read 1255=item $handle->start_read
839 1256
840In rare cases you actually do not want to read anything from the 1257In rare cases you actually do not want to read anything from the
841socket. In this case you can call C<stop_read>. Neither C<on_read> no 1258socket. In this case you can call C<stop_read>. Neither C<on_read> nor
842any queued callbacks will be executed then. To start reading again, call 1259any queued callbacks will be executed then. To start reading again, call
843C<start_read>. 1260C<start_read>.
844 1261
1262Note that AnyEvent::Handle will automatically C<start_read> for you when
1263you change the C<on_read> callback or push/unshift a read callback, and it
1264will automatically C<stop_read> for you when neither C<on_read> is set nor
1265there are any read requests in the queue.
1266
1267These methods will have no effect when in TLS mode (as TLS doesn't support
1268half-duplex connections).
1269
845=cut 1270=cut
846 1271
847sub stop_read { 1272sub stop_read {
848 my ($self) = @_; 1273 my ($self) = @_;
849 1274
850 delete $self->{rw}; 1275 delete $self->{_rw} unless $self->{tls};
851} 1276}
852 1277
853sub start_read { 1278sub start_read {
854 my ($self) = @_; 1279 my ($self) = @_;
855 1280
856 unless ($self->{rw} || $self->{eof}) { 1281 unless ($self->{_rw} || $self->{_eof}) {
857 Scalar::Util::weaken $self; 1282 Scalar::Util::weaken $self;
858 1283
859 $self->{rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub { 1284 $self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub {
860 my $rbuf = $self->{filter_r} ? \my $buf : \$self->{rbuf}; 1285 my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf});
861 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;
862 1287
863 if ($len > 0) { 1288 if ($len > 0) {
864 $self->{filter_r} 1289 $self->{_activity} = AnyEvent->now;
865 ? $self->{filter_r}->($self, $rbuf) 1290
866 : $self->_drain_rbuf; 1291 if ($self->{tls}) {
1292 Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf);
1293
1294 &_dotls ($self);
1295 } else {
1296 $self->_drain_rbuf unless $self->{_in_drain};
1297 }
867 1298
868 } elsif (defined $len) { 1299 } elsif (defined $len) {
869 delete $self->{rw}; 1300 delete $self->{_rw};
870 $self->{eof} = 1; 1301 $self->{_eof} = 1;
871 $self->_drain_rbuf; 1302 $self->_drain_rbuf unless $self->{_in_drain};
872 1303
873 } elsif ($! != EAGAIN && $! != EINTR && $! != &AnyEvent::Util::WSAWOULDBLOCK) { 1304 } elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) {
874 return $self->error; 1305 return $self->_error ($!, 1);
875 } 1306 }
876 }); 1307 });
877 } 1308 }
878} 1309}
879 1310
1311# poll the write BIO and send the data if applicable
880sub _dotls { 1312sub _dotls {
881 my ($self) = @_; 1313 my ($self) = @_;
882 1314
1315 my $tmp;
1316
883 if (length $self->{tls_wbuf}) { 1317 if (length $self->{_tls_wbuf}) {
884 while ((my $len = Net::SSLeay::write ($self->{tls}, $self->{tls_wbuf})) > 0) { 1318 while (($tmp = Net::SSLeay::write ($self->{tls}, $self->{_tls_wbuf})) > 0) {
885 substr $self->{tls_wbuf}, 0, $len, ""; 1319 substr $self->{_tls_wbuf}, 0, $tmp, "";
886 } 1320 }
887 } 1321 }
888 1322
889 if (defined (my $buf = Net::SSLeay::BIO_read ($self->{tls_wbio}))) { 1323 while (defined ($tmp = Net::SSLeay::read ($self->{tls}))) {
1324 unless (length $tmp) {
1325 # let's treat SSL-eof as we treat normal EOF
1326 delete $self->{_rw};
1327 $self->{_eof} = 1;
1328 &_freetls;
1329 }
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
1336 $tmp = Net::SSLeay::get_error ($self->{tls}, -1);
1337
1338 if ($tmp != Net::SSLeay::ERROR_WANT_READ ()) {
1339 if ($tmp == Net::SSLeay::ERROR_SYSCALL ()) {
1340 return $self->_error ($!, 1);
1341 } elsif ($tmp == Net::SSLeay::ERROR_SSL ()) {
1342 return $self->_error (&Errno::EIO, 1);
1343 }
1344
1345 # all other errors are fine for our purposes
1346 }
1347
1348 while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) {
890 $self->{wbuf} .= $buf; 1349 $self->{wbuf} .= $tmp;
891 $self->_drain_wbuf; 1350 $self->_drain_wbuf;
892 }
893
894 while (defined (my $buf = Net::SSLeay::read ($self->{tls}))) {
895 $self->{rbuf} .= $buf;
896 $self->_drain_rbuf;
897 }
898
899 my $err = Net::SSLeay::get_error ($self->{tls}, -1);
900
901 if ($err!= Net::SSLeay::ERROR_WANT_READ ()) {
902 if ($err == Net::SSLeay::ERROR_SYSCALL ()) {
903 $self->error;
904 } elsif ($err == Net::SSLeay::ERROR_SSL ()) {
905 $! = &Errno::EIO;
906 $self->error;
907 }
908
909 # all others are fine for our purposes
910 } 1351 }
911} 1352}
912 1353
913=item $handle->starttls ($tls[, $tls_ctx]) 1354=item $handle->starttls ($tls[, $tls_ctx])
914 1355
920C<"connect">, C<"accept"> or an existing Net::SSLeay object). 1361C<"connect">, C<"accept"> or an existing Net::SSLeay object).
921 1362
922The second argument is the optional C<Net::SSLeay::CTX> object that is 1363The second argument is the optional C<Net::SSLeay::CTX> object that is
923used when AnyEvent::Handle has to create its own TLS connection object. 1364used when AnyEvent::Handle has to create its own TLS connection object.
924 1365
925=cut 1366The TLS connection object will end up in C<< $handle->{tls} >> after this
1367call and can be used or changed to your liking. Note that the handshake
1368might have already started when this function returns.
926 1369
927# TODO: maybe document... 1370If it an error to start a TLS handshake more than once per
1371AnyEvent::Handle object (this is due to bugs in OpenSSL).
1372
1373=cut
1374
928sub starttls { 1375sub starttls {
929 my ($self, $ssl, $ctx) = @_; 1376 my ($self, $ssl, $ctx) = @_;
930 1377
931 $self->stoptls; 1378 require Net::SSLeay;
932 1379
1380 Carp::croak "it is an error to call starttls more than once on an AnyEvent::Handle object"
1381 if $self->{tls};
1382
933 if ($ssl eq "accept") { 1383 if ($ssl eq "accept") {
934 $ssl = Net::SSLeay::new ($ctx || TLS_CTX ()); 1384 $ssl = Net::SSLeay::new ($ctx || TLS_CTX ());
935 Net::SSLeay::set_accept_state ($ssl); 1385 Net::SSLeay::set_accept_state ($ssl);
936 } elsif ($ssl eq "connect") { 1386 } elsif ($ssl eq "connect") {
937 $ssl = Net::SSLeay::new ($ctx || TLS_CTX ()); 1387 $ssl = Net::SSLeay::new ($ctx || TLS_CTX ());
943 # 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)
944 # but the openssl maintainers basically said: "trust us, it just works". 1394 # but the openssl maintainers basically said: "trust us, it just works".
945 # (unfortunately, we have to hardcode constants because the abysmally misdesigned 1395 # (unfortunately, we have to hardcode constants because the abysmally misdesigned
946 # and mismaintained ssleay-module doesn't even offer them). 1396 # and mismaintained ssleay-module doesn't even offer them).
947 # 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.
948 Net::SSLeay::CTX_set_mode ($self->{tls}, 1405 Net::SSLeay::CTX_set_mode ($self->{tls},
949 (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1) 1406 (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1)
950 | (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));
951 1408
952 $self->{tls_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); 1409 $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
953 $self->{tls_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); 1410 $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ());
954 1411
955 Net::SSLeay::set_bio ($ssl, $self->{tls_rbio}, $self->{tls_wbio}); 1412 Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio});
956 1413
957 $self->{filter_w} = sub { 1414 &_dotls; # need to trigger the initial handshake
958 $_[0]{tls_wbuf} .= ${$_[1]}; 1415 $self->start_read; # make sure we actually do read
959 &_dotls;
960 };
961 $self->{filter_r} = sub {
962 Net::SSLeay::BIO_write ($_[0]{tls_rbio}, ${$_[1]});
963 &_dotls;
964 };
965} 1416}
966 1417
967=item $handle->stoptls 1418=item $handle->stoptls
968 1419
969Destroys the SSL connection, if any. Partial read or write data will be 1420Shuts down the SSL connection - this makes a proper EOF handshake by
970lost. 1421sending a close notify to the other side, but since OpenSSL doesn't
1422support non-blocking shut downs, it is not possible to re-use the stream
1423afterwards.
971 1424
972=cut 1425=cut
973 1426
974sub stoptls { 1427sub stoptls {
975 my ($self) = @_; 1428 my ($self) = @_;
976 1429
1430 if ($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
977 Net::SSLeay::free (delete $self->{tls}) if $self->{tls}; 1446 Net::SSLeay::free (delete $self->{tls});
978 delete $self->{tls_rbio}; 1447
979 delete $self->{tls_wbio}; 1448 delete @$self{qw(_rbio _wbio _tls_wbuf)};
980 delete $self->{tls_wbuf};
981 delete $self->{filter_r};
982 delete $self->{filter_w};
983} 1449}
984 1450
985sub DESTROY { 1451sub DESTROY {
986 my $self = shift; 1452 my $self = shift;
987 1453
988 $self->stoptls; 1454 &_freetls;
1455
1456 my $linger = exists $self->{linger} ? $self->{linger} : 3600;
1457
1458 if ($linger && length $self->{wbuf}) {
1459 my $fh = delete $self->{fh};
1460 my $wbuf = delete $self->{wbuf};
1461
1462 my @linger;
1463
1464 push @linger, AnyEvent->io (fh => $fh, poll => "w", cb => sub {
1465 my $len = syswrite $fh, $wbuf, length $wbuf;
1466
1467 if ($len > 0) {
1468 substr $wbuf, 0, $len, "";
1469 } else {
1470 @linger = (); # end
1471 }
1472 });
1473 push @linger, AnyEvent->timer (after => $linger, cb => sub {
1474 @linger = ();
1475 });
1476 }
1477}
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 = ();
989} 1502}
990 1503
991=item AnyEvent::Handle::TLS_CTX 1504=item AnyEvent::Handle::TLS_CTX
992 1505
993This function creates and returns the Net::SSLeay::CTX object used by 1506This function creates and returns the Net::SSLeay::CTX object used by
1023 } 1536 }
1024} 1537}
1025 1538
1026=back 1539=back
1027 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
1613=head1 SUBCLASSING AnyEvent::Handle
1614
1615In many cases, you might want to subclass AnyEvent::Handle.
1616
1617To make this easier, a given version of AnyEvent::Handle uses these
1618conventions:
1619
1620=over 4
1621
1622=item * all constructor arguments become object members.
1623
1624At least initially, when you pass a C<tls>-argument to the constructor it
1625will end up in C<< $handle->{tls} >>. Those members might be changed or
1626mutated later on (for example C<tls> will hold the TLS connection object).
1627
1628=item * other object member names are prefixed with an C<_>.
1629
1630All object members not explicitly documented (internal use) are prefixed
1631with an underscore character, so the remaining non-C<_>-namespace is free
1632for use for subclasses.
1633
1634=item * all members not documented here and not prefixed with an underscore
1635are free to use in subclasses.
1636
1637Of course, new versions of AnyEvent::Handle may introduce more "public"
1638member variables, but thats just life, at least it is documented.
1639
1640=back
1641
1028=head1 AUTHOR 1642=head1 AUTHOR
1029 1643
1030Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>. 1644Robin Redeker C<< <elmex at ta-sa.org> >>, Marc Lehmann <schmorp@schmorp.de>.
1031 1645
1032=cut 1646=cut

Diff Legend

Removed lines
+ Added lines
< Changed lines
> Changed lines