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Revision 1.185 by root, Thu Sep 3 19:48:27 2009 UTC vs.
Revision 1.200 by root, Tue Oct 12 06:47:54 2010 UTC

1=head1 NAME 1=head1 NAME
2 2
3AnyEvent::Handle - non-blocking I/O on file handles via AnyEvent 3AnyEvent::Handle - non-blocking I/O on streaming handles via AnyEvent
4 4
5=head1 SYNOPSIS 5=head1 SYNOPSIS
6 6
7 use AnyEvent; 7 use AnyEvent;
8 use AnyEvent::Handle; 8 use AnyEvent::Handle;
… …
14 on_error => sub { 14 on_error => sub {
15 my ($hdl, $fatal, $msg) = @_; 15 my ($hdl, $fatal, $msg) = @_;
16 warn "got error $msg\n"; 16 warn "got error $msg\n";
17 $hdl->destroy; 17 $hdl->destroy;
18 $cv->send; 18 $cv->send;
19 ); 19 };
20 20
21 # send some request line 21 # send some request line
22 $hdl->push_write ("getinfo\015\012"); 22 $hdl->push_write ("getinfo\015\012");
23 23
24 # read the response line 24 # read the response line
… …
30 30
31 $cv->recv; 31 $cv->recv;
32 32
33=head1 DESCRIPTION 33=head1 DESCRIPTION
34 34
35This module is a helper module to make it easier to do event-based I/O on 35This is a helper module to make it easier to do event-based I/O on
36filehandles. 36stream-based filehandles (sockets, pipes, and other stream things).
37 37
38The L<AnyEvent::Intro> tutorial contains some well-documented 38The L<AnyEvent::Intro> tutorial contains some well-documented
39AnyEvent::Handle examples. 39AnyEvent::Handle examples.
40 40
41In the following, when the documentation refers to of "bytes" then this 41In the following, where the documentation refers to "bytes", it means
42means characters. As sysread and syswrite are used for all I/O, their 42characters. As sysread and syswrite are used for all I/O, their
43treatment of characters applies to this module as well. 43treatment of characters applies to this module as well.
44 44
45At the very minimum, you should specify C<fh> or C<connect>, and the 45At the very minimum, you should specify C<fh> or C<connect>, and the
46C<on_error> callback. 46C<on_error> callback.
47 47
… …
79 79
80=head1 METHODS 80=head1 METHODS
81 81
82=over 4 82=over 4
83 83
84=item $handle = B<new> AnyEvent::TLS fh => $filehandle, key => value... 84=item $handle = B<new> AnyEvent::Handle fh => $filehandle, key => value...
85 85
86The constructor supports these arguments (all as C<< key => value >> pairs). 86The constructor supports these arguments (all as C<< key => value >> pairs).
87 87
88=over 4 88=over 4
89 89
… …
118prepare the file handle with parameters required for the actual connect 118prepare the file handle with parameters required for the actual connect
119(as opposed to settings that can be changed when the connection is already 119(as opposed to settings that can be changed when the connection is already
120established). 120established).
121 121
122The return value of this callback should be the connect timeout value in 122The return value of this callback should be the connect timeout value in
123seconds (or C<0>, or C<undef>, or the empty list, to indicate the default 123seconds (or C<0>, or C<undef>, or the empty list, to indicate that the
124timeout is to be used). 124default timeout is to be used).
125 125
126=item on_connect => $cb->($handle, $host, $port, $retry->()) 126=item on_connect => $cb->($handle, $host, $port, $retry->())
127 127
128This callback is called when a connection has been successfully established. 128This callback is called when a connection has been successfully established.
129 129
130The actual numeric host and port (the socket peername) are passed as 130The peer's numeric host and port (the socket peername) are passed as
131parameters, together with a retry callback. 131parameters, together with a retry callback.
132 132
133When, for some reason, the handle is not acceptable, then calling 133If, for some reason, the handle is not acceptable, calling C<$retry>
134C<$retry> will continue with the next conenction target (in case of 134will continue with the next connection target (in case of multi-homed
135multi-homed hosts or SRV records there can be multiple connection 135hosts or SRV records there can be multiple connection endpoints). At the
136endpoints). When it is called then the read and write queues, eof status, 136time it is called the read and write queues, eof status, tls status and
137tls status and similar properties of the handle are being reset. 137similar properties of the handle will have been reset.
138 138
139In most cases, ignoring the C<$retry> parameter is the way to go. 139In most cases, you should ignore the C<$retry> parameter.
140 140
141=item on_connect_error => $cb->($handle, $message) 141=item on_connect_error => $cb->($handle, $message)
142 142
143This callback is called when the conenction could not be 143This callback is called when the connection could not be
144established. C<$!> will contain the relevant error code, and C<$message> a 144established. C<$!> will contain the relevant error code, and C<$message> a
145message describing it (usually the same as C<"$!">). 145message describing it (usually the same as C<"$!">).
146 146
147If this callback isn't specified, then C<on_error> will be called with a 147If this callback isn't specified, then C<on_error> will be called with a
148fatal error instead. 148fatal error instead.
… …
151 151
152=item on_error => $cb->($handle, $fatal, $message) 152=item on_error => $cb->($handle, $fatal, $message)
153 153
154This is the error callback, which is called when, well, some error 154This is the error callback, which is called when, well, some error
155occured, such as not being able to resolve the hostname, failure to 155occured, such as not being able to resolve the hostname, failure to
156connect or a read error. 156connect, or a read error.
157 157
158Some errors are fatal (which is indicated by C<$fatal> being true). On 158Some errors are fatal (which is indicated by C<$fatal> being true). On
159fatal errors the handle object will be destroyed (by a call to C<< -> 159fatal errors the handle object will be destroyed (by a call to C<< ->
160destroy >>) after invoking the error callback (which means you are free to 160destroy >>) after invoking the error callback (which means you are free to
161examine the handle object). Examples of fatal errors are an EOF condition 161examine the handle object). Examples of fatal errors are an EOF condition
162with active (but unsatisifable) read watchers (C<EPIPE>) or I/O errors. In 162with active (but unsatisifable) read watchers (C<EPIPE>) or I/O errors. In
163cases where the other side can close the connection at their will it is 163cases where the other side can close the connection at will, it is
164often easiest to not report C<EPIPE> errors in this callback. 164often easiest to not report C<EPIPE> errors in this callback.
165 165
166AnyEvent::Handle tries to find an appropriate error code for you to check 166AnyEvent::Handle tries to find an appropriate error code for you to check
167against, but in some cases (TLS errors), this does not work well. It is 167against, but in some cases (TLS errors), this does not work well. It is
168recommended to always output the C<$message> argument in human-readable 168recommended to always output the C<$message> argument in human-readable
169error messages (it's usually the same as C<"$!">). 169error messages (it's usually the same as C<"$!">).
170 170
171Non-fatal errors can be retried by simply returning, but it is recommended 171Non-fatal errors can be retried by returning, but it is recommended
172to simply ignore this parameter and instead abondon the handle object 172to simply ignore this parameter and instead abondon the handle object
173when this callback is invoked. Examples of non-fatal errors are timeouts 173when this callback is invoked. Examples of non-fatal errors are timeouts
174C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>). 174C<ETIMEDOUT>) or badly-formatted data (C<EBADMSG>).
175 175
176On callback entrance, the value of C<$!> contains the operating system 176On entry to the callback, the value of C<$!> contains the operating
177error code (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT>, C<EBADMSG> or 177system error code (or C<ENOSPC>, C<EPIPE>, C<ETIMEDOUT>, C<EBADMSG> or
178C<EPROTO>). 178C<EPROTO>).
179 179
180While not mandatory, it is I<highly> recommended to set this callback, as 180While not mandatory, it is I<highly> recommended to set this callback, as
181you will not be notified of errors otherwise. The default simply calls 181you will not be notified of errors otherwise. The default just calls
182C<croak>. 182C<croak>.
183 183
184=item on_read => $cb->($handle) 184=item on_read => $cb->($handle)
185 185
186This sets the default read callback, which is called when data arrives 186This sets the default read callback, which is called when data arrives
… …
191To access (and remove data from) the read buffer, use the C<< ->rbuf >> 191To access (and remove data from) the read buffer, use the C<< ->rbuf >>
192method or access the C<< $handle->{rbuf} >> member directly. Note that you 192method or access the C<< $handle->{rbuf} >> member directly. Note that you
193must not enlarge or modify the read buffer, you can only remove data at 193must not enlarge or modify the read buffer, you can only remove data at
194the beginning from it. 194the beginning from it.
195 195
196You can also call C<< ->push_read (...) >> or any other function that
197modifies the read queue. Or do both. Or ...
198
196When an EOF condition is detected then AnyEvent::Handle will first try to 199When an EOF condition is detected, AnyEvent::Handle will first try to
197feed all the remaining data to the queued callbacks and C<on_read> before 200feed all the remaining data to the queued callbacks and C<on_read> before
198calling the C<on_eof> callback. If no progress can be made, then a fatal 201calling the C<on_eof> callback. If no progress can be made, then a fatal
199error will be raised (with C<$!> set to C<EPIPE>). 202error will be raised (with C<$!> set to C<EPIPE>).
200 203
201Note that, unlike requests in the read queue, an C<on_read> callback 204Note that, unlike requests in the read queue, an C<on_read> callback
… …
220set, then a fatal error will be raised with C<$!> set to <0>. 223set, then a fatal error will be raised with C<$!> set to <0>.
221 224
222=item on_drain => $cb->($handle) 225=item on_drain => $cb->($handle)
223 226
224This sets the callback that is called when the write buffer becomes empty 227This sets the callback that is called when the write buffer becomes empty
225(or when the callback is set and the buffer is empty already). 228(or immediately if the buffer is empty already).
226 229
227To append to the write buffer, use the C<< ->push_write >> method. 230To append to the write buffer, use the C<< ->push_write >> method.
228 231
229This callback is useful when you don't want to put all of your write data 232This callback is useful when you don't want to put all of your write data
230into the queue at once, for example, when you want to write the contents 233into the queue at once, for example, when you want to write the contents
… …
242many seconds pass without a successful read or write on the underlying 245many seconds pass without a successful read or write on the underlying
243file handle (or a call to C<timeout_reset>), the C<on_timeout> callback 246file handle (or a call to C<timeout_reset>), the C<on_timeout> callback
244will be invoked (and if that one is missing, a non-fatal C<ETIMEDOUT> 247will be invoked (and if that one is missing, a non-fatal C<ETIMEDOUT>
245error will be raised). 248error will be raised).
246 249
247There are three variants of the timeouts that work fully independent 250There are three variants of the timeouts that work independently
248of each other, for both read and write, just read, and just write: 251of each other, for both read and write, just read, and just write:
249C<timeout>, C<rtimeout> and C<wtimeout>, with corresponding callbacks 252C<timeout>, C<rtimeout> and C<wtimeout>, with corresponding callbacks
250C<on_timeout>, C<on_rtimeout> and C<on_wtimeout>, and reset functions 253C<on_timeout>, C<on_rtimeout> and C<on_wtimeout>, and reset functions
251C<timeout_reset>, C<rtimeout_reset>, and C<wtimeout_reset>. 254C<timeout_reset>, C<rtimeout_reset>, and C<wtimeout_reset>.
252 255
253Note that timeout processing is also active when you currently do not have 256Note that timeout processing is active even when you do not have
254any outstanding read or write requests: If you plan to keep the connection 257any outstanding read or write requests: If you plan to keep the connection
255idle then you should disable the timout temporarily or ignore the timeout 258idle then you should disable the timeout temporarily or ignore the timeout
256in the C<on_timeout> callback, in which case AnyEvent::Handle will simply 259in the C<on_timeout> callback, in which case AnyEvent::Handle will simply
257restart the timeout. 260restart the timeout.
258 261
259Zero (the default) disables this timeout. 262Zero (the default) disables this timeout.
260 263
… …
276amount of data without a callback ever being called as long as the line 279amount of data without a callback ever being called as long as the line
277isn't finished). 280isn't finished).
278 281
279=item autocork => <boolean> 282=item autocork => <boolean>
280 283
281When disabled (the default), then C<push_write> will try to immediately 284When disabled (the default), C<push_write> will try to immediately
282write the data to the handle, if possible. This avoids having to register 285write the data to the handle if possible. This avoids having to register
283a write watcher and wait for the next event loop iteration, but can 286a write watcher and wait for the next event loop iteration, but can
284be inefficient if you write multiple small chunks (on the wire, this 287be inefficient if you write multiple small chunks (on the wire, this
285disadvantage is usually avoided by your kernel's nagle algorithm, see 288disadvantage is usually avoided by your kernel's nagle algorithm, see
286C<no_delay>, but this option can save costly syscalls). 289C<no_delay>, but this option can save costly syscalls).
287 290
288When enabled, then writes will always be queued till the next event loop 291When enabled, writes will always be queued till the next event loop
289iteration. This is efficient when you do many small writes per iteration, 292iteration. This is efficient when you do many small writes per iteration,
290but less efficient when you do a single write only per iteration (or when 293but less efficient when you do a single write only per iteration (or when
291the write buffer often is full). It also increases write latency. 294the write buffer often is full). It also increases write latency.
292 295
293=item no_delay => <boolean> 296=item no_delay => <boolean>
… …
297the Nagle algorithm, and usually it is beneficial. 300the Nagle algorithm, and usually it is beneficial.
298 301
299In some situations you want as low a delay as possible, which can be 302In some situations you want as low a delay as possible, which can be
300accomplishd by setting this option to a true value. 303accomplishd by setting this option to a true value.
301 304
302The default is your opertaing system's default behaviour (most likely 305The default is your operating system's default behaviour (most likely
303enabled), this option explicitly enables or disables it, if possible. 306enabled). This option explicitly enables or disables it, if possible.
304 307
305=item keepalive => <boolean> 308=item keepalive => <boolean>
306 309
307Enables (default disable) the SO_KEEPALIVE option on the stream socket: 310Enables (default disable) the SO_KEEPALIVE option on the stream socket:
308normally, TCP connections have no time-out once established, so TCP 311normally, TCP connections have no time-out once established, so TCP
309conenctions, once established, can stay alive forever even when the other 312connections, once established, can stay alive forever even when the other
310side has long gone. TCP keepalives are a cheap way to take down long-lived 313side has long gone. TCP keepalives are a cheap way to take down long-lived
311TCP connections whent he other side becomes unreachable. While the default 314TCP connections when the other side becomes unreachable. While the default
312is OS-dependent, TCP keepalives usually kick in after around two hours, 315is OS-dependent, TCP keepalives usually kick in after around two hours,
313and, if the other side doesn't reply, take down the TCP connection some 10 316and, if the other side doesn't reply, take down the TCP connection some 10
314to 15 minutes later. 317to 15 minutes later.
315 318
316It is harmless to specify this option for file handles that do not support 319It is harmless to specify this option for file handles that do not support
… …
334already have occured on BSD systems), but at least it will protect you 337already have occured on BSD systems), but at least it will protect you
335from most attacks. 338from most attacks.
336 339
337=item read_size => <bytes> 340=item read_size => <bytes>
338 341
339The default read block size (the amount of bytes this module will 342The default read block size (the number of bytes this module will
340try to read during each loop iteration, which affects memory 343try to read during each loop iteration, which affects memory
341requirements). Default: C<8192>. 344requirements). Default: C<8192>.
342 345
343=item low_water_mark => <bytes> 346=item low_water_mark => <bytes>
344 347
345Sets the amount of bytes (default: C<0>) that make up an "empty" write 348Sets the number of bytes (default: C<0>) that make up an "empty" write
346buffer: If the write reaches this size or gets even samller it is 349buffer: If the buffer reaches this size or gets even samller it is
347considered empty. 350considered empty.
348 351
349Sometimes it can be beneficial (for performance reasons) to add data to 352Sometimes it can be beneficial (for performance reasons) to add data to
350the write buffer before it is fully drained, but this is a rare case, as 353the write buffer before it is fully drained, but this is a rare case, as
351the operating system kernel usually buffers data as well, so the default 354the operating system kernel usually buffers data as well, so the default
352is good in almost all cases. 355is good in almost all cases.
353 356
354=item linger => <seconds> 357=item linger => <seconds>
355 358
356If non-zero (default: C<3600>), then the destructor of the 359If this is non-zero (default: C<3600>), the destructor of the
357AnyEvent::Handle object will check whether there is still outstanding 360AnyEvent::Handle object will check whether there is still outstanding
358write data and will install a watcher that will write this data to the 361write data and will install a watcher that will write this data to the
359socket. No errors will be reported (this mostly matches how the operating 362socket. No errors will be reported (this mostly matches how the operating
360system treats outstanding data at socket close time). 363system treats outstanding data at socket close time).
361 364
… …
368A string used to identify the remote site - usually the DNS hostname 371A string used to identify the remote site - usually the DNS hostname
369(I<not> IDN!) used to create the connection, rarely the IP address. 372(I<not> IDN!) used to create the connection, rarely the IP address.
370 373
371Apart from being useful in error messages, this string is also used in TLS 374Apart from being useful in error messages, this string is also used in TLS
372peername verification (see C<verify_peername> in L<AnyEvent::TLS>). This 375peername verification (see C<verify_peername> in L<AnyEvent::TLS>). This
373verification will be skipped when C<peername> is not specified or 376verification will be skipped when C<peername> is not specified or is
374C<undef>. 377C<undef>.
375 378
376=item tls => "accept" | "connect" | Net::SSLeay::SSL object 379=item tls => "accept" | "connect" | Net::SSLeay::SSL object
377 380
378When this parameter is given, it enables TLS (SSL) mode, that means 381When this parameter is given, it enables TLS (SSL) mode, that means
379AnyEvent will start a TLS handshake as soon as the conenction has been 382AnyEvent will start a TLS handshake as soon as the connection has been
380established and will transparently encrypt/decrypt data afterwards. 383established and will transparently encrypt/decrypt data afterwards.
381 384
382All TLS protocol errors will be signalled as C<EPROTO>, with an 385All TLS protocol errors will be signalled as C<EPROTO>, with an
383appropriate error message. 386appropriate error message.
384 387
… …
404B<IMPORTANT:> since Net::SSLeay "objects" are really only integers, 407B<IMPORTANT:> since Net::SSLeay "objects" are really only integers,
405passing in the wrong integer will lead to certain crash. This most often 408passing in the wrong integer will lead to certain crash. This most often
406happens when one uses a stylish C<< tls => 1 >> and is surprised about the 409happens when one uses a stylish C<< tls => 1 >> and is surprised about the
407segmentation fault. 410segmentation fault.
408 411
409See the C<< ->starttls >> method for when need to start TLS negotiation later. 412Use the C<< ->starttls >> method if you need to start TLS negotiation later.
410 413
411=item tls_ctx => $anyevent_tls 414=item tls_ctx => $anyevent_tls
412 415
413Use the given C<AnyEvent::TLS> object to create the new TLS connection 416Use the given C<AnyEvent::TLS> object to create the new TLS connection
414(unless a connection object was specified directly). If this parameter is 417(unless a connection object was specified directly). If this parameter is
… …
429 432
430TLS handshake failures will not cause C<on_error> to be invoked when this 433TLS handshake failures will not cause C<on_error> to be invoked when this
431callback is in effect, instead, the error message will be passed to C<on_starttls>. 434callback is in effect, instead, the error message will be passed to C<on_starttls>.
432 435
433Without this callback, handshake failures lead to C<on_error> being 436Without this callback, handshake failures lead to C<on_error> being
434called, as normal. 437called as usual.
435 438
436Note that you cannot call C<starttls> right again in this callback. If you 439Note that you cannot just call C<starttls> again in this callback. If you
437need to do that, start an zero-second timer instead whose callback can 440need to do that, start an zero-second timer instead whose callback can
438then call C<< ->starttls >> again. 441then call C<< ->starttls >> again.
439 442
440=item on_stoptls => $cb->($handle) 443=item on_stoptls => $cb->($handle)
441 444
… …
531} 534}
532 535
533sub _start { 536sub _start {
534 my ($self) = @_; 537 my ($self) = @_;
535 538
539 # too many clueless people try to use udp and similar sockets
540 # with AnyEvent::Handle, do them a favour.
541 my $type = getsockopt $self->{fh}, Socket::SOL_SOCKET (), Socket::SO_TYPE ();
542 Carp::croak "AnyEvent::Handle: only stream sockets supported, anything else will NOT work!"
543 if Socket::SOCK_STREAM () != (unpack "I", $type) && defined $type;
544
536 AnyEvent::Util::fh_nonblocking $self->{fh}, 1; 545 AnyEvent::Util::fh_nonblocking $self->{fh}, 1;
537 546
538 $self->{_activity} = 547 $self->{_activity} =
539 $self->{_ractivity} = 548 $self->{_ractivity} =
540 $self->{_wactivity} = AE::now; 549 $self->{_wactivity} = AE::now;
… …
549 $self->oobinline (exists $self->{oobinline} ? delete $self->{oobinline} : 1); 558 $self->oobinline (exists $self->{oobinline} ? delete $self->{oobinline} : 1);
550 559
551 $self->starttls (delete $self->{tls}, delete $self->{tls_ctx}) 560 $self->starttls (delete $self->{tls}, delete $self->{tls_ctx})
552 if $self->{tls}; 561 if $self->{tls};
553 562
554 $self->on_drain (delete $self->{on_drain}) if $self->{on_drain}; 563 $self->on_drain (delete $self->{on_drain} ) if $self->{on_drain};
555 564
556 $self->start_read 565 $self->start_read
557 if $self->{on_read} || @{ $self->{_queue} }; 566 if $self->{on_read} || @{ $self->{_queue} };
558 567
559 $self->_drain_wbuf; 568 $self->_drain_wbuf;
… …
566 $message ||= "$!"; 575 $message ||= "$!";
567 576
568 if ($self->{on_error}) { 577 if ($self->{on_error}) {
569 $self->{on_error}($self, $fatal, $message); 578 $self->{on_error}($self, $fatal, $message);
570 $self->destroy if $fatal; 579 $self->destroy if $fatal;
571 } elsif ($self->{fh}) { 580 } elsif ($self->{fh} || $self->{connect}) {
572 $self->destroy; 581 $self->destroy;
573 Carp::croak "AnyEvent::Handle uncaught error: $message"; 582 Carp::croak "AnyEvent::Handle uncaught error: $message";
574 } 583 }
575} 584}
576 585
… …
635=cut 644=cut
636 645
637sub no_delay { 646sub no_delay {
638 $_[0]{no_delay} = $_[1]; 647 $_[0]{no_delay} = $_[1];
639 648
640 eval {
641 local $SIG{__DIE__};
642 setsockopt $_[0]{fh}, Socket::IPPROTO_TCP (), Socket::TCP_NODELAY (), int $_[1] 649 setsockopt $_[0]{fh}, Socket::IPPROTO_TCP (), Socket::TCP_NODELAY (), int $_[1]
643 if $_[0]{fh}; 650 if $_[0]{fh};
644 };
645} 651}
646 652
647=item $handle->keepalive ($boolean) 653=item $handle->keepalive ($boolean)
648 654
649Enables or disables the C<keepalive> setting (see constructor argument of 655Enables or disables the C<keepalive> setting (see constructor argument of
… …
709 715
710Replace the current C<on_stoptls> callback (see the C<on_stoptls> constructor argument). 716Replace the current C<on_stoptls> callback (see the C<on_stoptls> constructor argument).
711 717
712=cut 718=cut
713 719
714sub on_starttls { 720sub on_stoptls {
715 $_[0]{on_stoptls} = $_[1]; 721 $_[0]{on_stoptls} = $_[1];
716} 722}
717 723
718=item $handle->rbuf_max ($max_octets) 724=item $handle->rbuf_max ($max_octets)
719 725
… …
831=item $handle->on_drain ($cb) 837=item $handle->on_drain ($cb)
832 838
833Sets the C<on_drain> callback or clears it (see the description of 839Sets the C<on_drain> callback or clears it (see the description of
834C<on_drain> in the constructor). 840C<on_drain> in the constructor).
835 841
842This method may invoke callbacks (and therefore the handle might be
843destroyed after it returns).
844
836=cut 845=cut
837 846
838sub on_drain { 847sub on_drain {
839 my ($self, $cb) = @_; 848 my ($self, $cb) = @_;
840 849
… …
847=item $handle->push_write ($data) 856=item $handle->push_write ($data)
848 857
849Queues the given scalar to be written. You can push as much data as you 858Queues the given scalar to be written. You can push as much data as you
850want (only limited by the available memory), as C<AnyEvent::Handle> 859want (only limited by the available memory), as C<AnyEvent::Handle>
851buffers it independently of the kernel. 860buffers it independently of the kernel.
861
862This method may invoke callbacks (and therefore the handle might be
863destroyed after it returns).
852 864
853=cut 865=cut
854 866
855sub _drain_wbuf { 867sub _drain_wbuf {
856 my ($self) = @_; 868 my ($self) = @_;
… …
902 @_ = ($WH{$type} ||= _load_func "$type\::anyevent_write_type" 914 @_ = ($WH{$type} ||= _load_func "$type\::anyevent_write_type"
903 or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::push_write") 915 or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::push_write")
904 ->($self, @_); 916 ->($self, @_);
905 } 917 }
906 918
919 # we downgrade here to avoid hard-to-track-down bugs,
920 # and diagnose the problem earlier and better.
921
907 if ($self->{tls}) { 922 if ($self->{tls}) {
908 $self->{_tls_wbuf} .= $_[0]; 923 utf8::downgrade $self->{_tls_wbuf} .= $_[0];
909 &_dotls ($self) if $self->{fh}; 924 &_dotls ($self) if $self->{fh};
910 } else { 925 } else {
911 $self->{wbuf} .= $_[0]; 926 utf8::downgrade $self->{wbuf} .= $_[0];
912 $self->_drain_wbuf if $self->{fh}; 927 $self->_drain_wbuf if $self->{fh};
913 } 928 }
914} 929}
915 930
916=item $handle->push_write (type => @args) 931=item $handle->push_write (type => @args)
917 932
918Instead of formatting your data yourself, you can also let this module 933Instead of formatting your data yourself, you can also let this module
919do the job by specifying a type and type-specific arguments. You 934do the job by specifying a type and type-specific arguments. You
920can also specify the (fully qualified) name of a package, in which 935can also specify the (fully qualified) name of a package, in which
921case AnyEvent tries to load the package and then expects to find the 936case AnyEvent tries to load the package and then expects to find the
922C<anyevent_read_type> function inside (see "custom write types", below). 937C<anyevent_write_type> function inside (see "custom write types", below).
923 938
924Predefined types are (if you have ideas for additional types, feel free to 939Predefined types are (if you have ideas for additional types, feel free to
925drop by and tell us): 940drop by and tell us):
926 941
927=over 4 942=over 4
… …
1030the peer. 1045the peer.
1031 1046
1032You can rely on the normal read queue and C<on_eof> handling 1047You can rely on the normal read queue and C<on_eof> handling
1033afterwards. This is the cleanest way to close a connection. 1048afterwards. This is the cleanest way to close a connection.
1034 1049
1050This method may invoke callbacks (and therefore the handle might be
1051destroyed after it returns).
1052
1035=cut 1053=cut
1036 1054
1037sub push_shutdown { 1055sub push_shutdown {
1038 my ($self) = @_; 1056 my ($self) = @_;
1039 1057
… …
1088ways, the "simple" way, using only C<on_read> and the "complex" way, using 1106ways, the "simple" way, using only C<on_read> and the "complex" way, using
1089a queue. 1107a queue.
1090 1108
1091In the simple case, you just install an C<on_read> callback and whenever 1109In the simple case, you just install an C<on_read> callback and whenever
1092new data arrives, it will be called. You can then remove some data (if 1110new data arrives, it will be called. You can then remove some data (if
1093enough is there) from the read buffer (C<< $handle->rbuf >>). Or you cna 1111enough is there) from the read buffer (C<< $handle->rbuf >>). Or you can
1094leave the data there if you want to accumulate more (e.g. when only a 1112leave the data there if you want to accumulate more (e.g. when only a
1095partial message has been received so far). 1113partial message has been received so far), or change the read queue with
1114e.g. C<push_read>.
1096 1115
1097In the more complex case, you want to queue multiple callbacks. In this 1116In the more complex case, you want to queue multiple callbacks. In this
1098case, AnyEvent::Handle will call the first queued callback each time new 1117case, AnyEvent::Handle will call the first queued callback each time new
1099data arrives (also the first time it is queued) and removes it when it has 1118data arrives (also the first time it is queued) and remove it when it has
1100done its job (see C<push_read>, below). 1119done its job (see C<push_read>, below).
1101 1120
1102This way you can, for example, push three line-reads, followed by reading 1121This way you can, for example, push three line-reads, followed by reading
1103a chunk of data, and AnyEvent::Handle will execute them in order. 1122a chunk of data, and AnyEvent::Handle will execute them in order.
1104 1123
… …
1235 1254
1236This replaces the currently set C<on_read> callback, or clears it (when 1255This replaces the currently set C<on_read> callback, or clears it (when
1237the new callback is C<undef>). See the description of C<on_read> in the 1256the new callback is C<undef>). See the description of C<on_read> in the
1238constructor. 1257constructor.
1239 1258
1259This method may invoke callbacks (and therefore the handle might be
1260destroyed after it returns).
1261
1240=cut 1262=cut
1241 1263
1242sub on_read { 1264sub on_read {
1243 my ($self, $cb) = @_; 1265 my ($self, $cb) = @_;
1244 1266
… …
1246 $self->_drain_rbuf if $cb; 1268 $self->_drain_rbuf if $cb;
1247} 1269}
1248 1270
1249=item $handle->rbuf 1271=item $handle->rbuf
1250 1272
1251Returns the read buffer (as a modifiable lvalue). 1273Returns the read buffer (as a modifiable lvalue). You can also access the
1274read buffer directly as the C<< ->{rbuf} >> member, if you want (this is
1275much faster, and no less clean).
1252 1276
1253You can access the read buffer directly as the C<< ->{rbuf} >> 1277The only operation allowed on the read buffer (apart from looking at it)
1254member, if you want. However, the only operation allowed on the 1278is removing data from its beginning. Otherwise modifying or appending to
1255read buffer (apart from looking at it) is removing data from its 1279it is not allowed and will lead to hard-to-track-down bugs.
1256beginning. Otherwise modifying or appending to it is not allowed and will
1257lead to hard-to-track-down bugs.
1258 1280
1259NOTE: The read buffer should only be used or modified if the C<on_read>, 1281NOTE: The read buffer should only be used or modified in the C<on_read>
1260C<push_read> or C<unshift_read> methods are used. The other read methods 1282callback or when C<push_read> or C<unshift_read> are used with a single
1261automatically manage the read buffer. 1283callback (i.e. untyped). Typed C<push_read> and C<unshift_read> methods
1284will manage the read buffer on their own.
1262 1285
1263=cut 1286=cut
1264 1287
1265sub rbuf : lvalue { 1288sub rbuf : lvalue {
1266 $_[0]{rbuf} 1289 $_[0]{rbuf}
… …
1283 1306
1284If enough data was available, then the callback must remove all data it is 1307If enough data was available, then the callback must remove all data it is
1285interested in (which can be none at all) and return a true value. After returning 1308interested in (which can be none at all) and return a true value. After returning
1286true, it will be removed from the queue. 1309true, it will be removed from the queue.
1287 1310
1311These methods may invoke callbacks (and therefore the handle might be
1312destroyed after it returns).
1313
1288=cut 1314=cut
1289 1315
1290our %RH; 1316our %RH;
1291 1317
1292sub register_read_type($$) { 1318sub register_read_type($$) {
… …
1314 my $cb = pop; 1340 my $cb = pop;
1315 1341
1316 if (@_) { 1342 if (@_) {
1317 my $type = shift; 1343 my $type = shift;
1318 1344
1345 $cb = ($RH{$type} ||= _load_func "$type\::anyevent_read_type"
1319 $cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::unshift_read") 1346 or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::unshift_read")
1320 ->($self, $cb, @_); 1347 ->($self, $cb, @_);
1321 } 1348 }
1322 1349
1323 unshift @{ $self->{_queue} }, $cb; 1350 unshift @{ $self->{_queue} }, $cb;
1324 $self->_drain_rbuf; 1351 $self->_drain_rbuf;
… …
1432the receive buffer when neither C<$accept> nor C<$reject> match, 1459the receive buffer when neither C<$accept> nor C<$reject> match,
1433and everything preceding and including the match will be accepted 1460and everything preceding and including the match will be accepted
1434unconditionally. This is useful to skip large amounts of data that you 1461unconditionally. This is useful to skip large amounts of data that you
1435know cannot be matched, so that the C<$accept> or C<$reject> regex do not 1462know cannot be matched, so that the C<$accept> or C<$reject> regex do not
1436have to start matching from the beginning. This is purely an optimisation 1463have to start matching from the beginning. This is purely an optimisation
1437and is usually worth only when you expect more than a few kilobytes. 1464and is usually worth it only when you expect more than a few kilobytes.
1438 1465
1439Example: expect a http header, which ends at C<\015\012\015\012>. Since we 1466Example: expect a http header, which ends at C<\015\012\015\012>. Since we
1440expect the header to be very large (it isn't in practise, but...), we use 1467expect the header to be very large (it isn't in practice, but...), we use
1441a skip regex to skip initial portions. The skip regex is tricky in that 1468a skip regex to skip initial portions. The skip regex is tricky in that
1442it only accepts something not ending in either \015 or \012, as these are 1469it only accepts something not ending in either \015 or \012, as these are
1443required for the accept regex. 1470required for the accept regex.
1444 1471
1445 $handle->push_read (regex => 1472 $handle->push_read (regex =>
… …
1710} 1737}
1711 1738
1712sub start_read { 1739sub start_read {
1713 my ($self) = @_; 1740 my ($self) = @_;
1714 1741
1715 unless ($self->{_rw} || $self->{_eof}) { 1742 unless ($self->{_rw} || $self->{_eof} || !$self->{fh}) {
1716 Scalar::Util::weaken $self; 1743 Scalar::Util::weaken $self;
1717 1744
1718 $self->{_rw} = AE::io $self->{fh}, 0, sub { 1745 $self->{_rw} = AE::io $self->{fh}, 0, sub {
1719 my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf}); 1746 my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf});
1720 my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf; 1747 my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf;
… …
1813 && ($tmp != $ERROR_SYSCALL || $!); 1840 && ($tmp != $ERROR_SYSCALL || $!);
1814 1841
1815 while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) { 1842 while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) {
1816 $self->{wbuf} .= $tmp; 1843 $self->{wbuf} .= $tmp;
1817 $self->_drain_wbuf; 1844 $self->_drain_wbuf;
1845 $self->{tls} or return; # tls session might have gone away in callback
1818 } 1846 }
1819 1847
1820 $self->{_on_starttls} 1848 $self->{_on_starttls}
1821 and Net::SSLeay::state ($self->{tls}) == Net::SSLeay::ST_OK () 1849 and Net::SSLeay::state ($self->{tls}) == Net::SSLeay::ST_OK ()
1822 and (delete $self->{_on_starttls})->($self, 1, "TLS/SSL connection established"); 1850 and (delete $self->{_on_starttls})->($self, 1, "TLS/SSL connection established");
… …
1844context in C<< $handle->{tls_ctx} >> after this call and can be used or 1872context in C<< $handle->{tls_ctx} >> after this call and can be used or
1845changed to your liking. Note that the handshake might have already started 1873changed to your liking. Note that the handshake might have already started
1846when this function returns. 1874when this function returns.
1847 1875
1848Due to bugs in OpenSSL, it might or might not be possible to do multiple 1876Due to bugs in OpenSSL, it might or might not be possible to do multiple
1849handshakes on the same stream. Best do not attempt to use the stream after 1877handshakes on the same stream. It is best to not attempt to use the
1850stopping TLS. 1878stream after stopping TLS.
1879
1880This method may invoke callbacks (and therefore the handle might be
1881destroyed after it returns).
1851 1882
1852=cut 1883=cut
1853 1884
1854our %TLS_CACHE; #TODO not yet documented, should we? 1885our %TLS_CACHE; #TODO not yet documented, should we?
1855 1886
… …
1921 1952
1922=item $handle->stoptls 1953=item $handle->stoptls
1923 1954
1924Shuts down the SSL connection - this makes a proper EOF handshake by 1955Shuts down the SSL connection - this makes a proper EOF handshake by
1925sending a close notify to the other side, but since OpenSSL doesn't 1956sending a close notify to the other side, but since OpenSSL doesn't
1926support non-blocking shut downs, it is not guarenteed that you can re-use 1957support non-blocking shut downs, it is not guaranteed that you can re-use
1927the stream afterwards. 1958the stream afterwards.
1959
1960This method may invoke callbacks (and therefore the handle might be
1961destroyed after it returns).
1928 1962
1929=cut 1963=cut
1930 1964
1931sub stoptls { 1965sub stoptls {
1932 my ($self) = @_; 1966 my ($self) = @_;
1933 1967
1934 if ($self->{tls}) { 1968 if ($self->{tls} && $self->{fh}) {
1935 Net::SSLeay::shutdown ($self->{tls}); 1969 Net::SSLeay::shutdown ($self->{tls});
1936 1970
1937 &_dotls; 1971 &_dotls;
1938 1972
1939# # we don't give a shit. no, we do, but we can't. no...#d# 1973# # we don't give a shit. no, we do, but we can't. no...#d#
… …
2016 2050
2017sub AnyEvent::Handle::destroyed::AUTOLOAD { 2051sub AnyEvent::Handle::destroyed::AUTOLOAD {
2018 #nop 2052 #nop
2019} 2053}
2020 2054
2055=item $handle->destroyed
2056
2057Returns false as long as the handle hasn't been destroyed by a call to C<<
2058->destroy >>, true otherwise.
2059
2060Can be useful to decide whether the handle is still valid after some
2061callback possibly destroyed the handle. For example, C<< ->push_write >>,
2062C<< ->starttls >> and other methods can call user callbacks, which in turn
2063can destroy the handle, so work can be avoided by checking sometimes:
2064
2065 $hdl->starttls ("accept");
2066 return if $hdl->destroyed;
2067 $hdl->push_write (...
2068
2069Note that the call to C<push_write> will silently be ignored if the handle
2070has been destroyed, so often you can just ignore the possibility of the
2071handle being destroyed.
2072
2073=cut
2074
2075sub destroyed { 0 }
2076sub AnyEvent::Handle::destroyed::destroyed { 1 }
2077
2021=item AnyEvent::Handle::TLS_CTX 2078=item AnyEvent::Handle::TLS_CTX
2022 2079
2023This function creates and returns the AnyEvent::TLS object used by default 2080This function creates and returns the AnyEvent::TLS object used by default
2024for TLS mode. 2081for TLS mode.
2025 2082
… …
2056 2113
2057=item I get different callback invocations in TLS mode/Why can't I pause 2114=item I get different callback invocations in TLS mode/Why can't I pause
2058reading? 2115reading?
2059 2116
2060Unlike, say, TCP, TLS connections do not consist of two independent 2117Unlike, say, TCP, TLS connections do not consist of two independent
2061communication channels, one for each direction. Or put differently. The 2118communication channels, one for each direction. Or put differently, the
2062read and write directions are not independent of each other: you cannot 2119read and write directions are not independent of each other: you cannot
2063write data unless you are also prepared to read, and vice versa. 2120write data unless you are also prepared to read, and vice versa.
2064 2121
2065This can mean than, in TLS mode, you might get C<on_error> or C<on_eof> 2122This means that, in TLS mode, you might get C<on_error> or C<on_eof>
2066callback invocations when you are not expecting any read data - the reason 2123callback invocations when you are not expecting any read data - the reason
2067is that AnyEvent::Handle always reads in TLS mode. 2124is that AnyEvent::Handle always reads in TLS mode.
2068 2125
2069During the connection, you have to make sure that you always have a 2126During the connection, you have to make sure that you always have a
2070non-empty read-queue, or an C<on_read> watcher. At the end of the 2127non-empty read-queue, or an C<on_read> watcher. At the end of the
… …
2084 my $data = delete $_[0]{rbuf}; 2141 my $data = delete $_[0]{rbuf};
2085 }); 2142 });
2086 2143
2087The reason to use C<on_error> is that TCP connections, due to latencies 2144The reason to use C<on_error> is that TCP connections, due to latencies
2088and packets loss, might get closed quite violently with an error, when in 2145and packets loss, might get closed quite violently with an error, when in
2089fact, all data has been received. 2146fact all data has been received.
2090 2147
2091It is usually better to use acknowledgements when transferring data, 2148It is usually better to use acknowledgements when transferring data,
2092to make sure the other side hasn't just died and you got the data 2149to make sure the other side hasn't just died and you got the data
2093intact. This is also one reason why so many internet protocols have an 2150intact. This is also one reason why so many internet protocols have an
2094explicit QUIT command. 2151explicit QUIT command.
… …
2111consider using C<< ->push_shutdown >> instead. 2168consider using C<< ->push_shutdown >> instead.
2112 2169
2113=item I want to contact a TLS/SSL server, I don't care about security. 2170=item I want to contact a TLS/SSL server, I don't care about security.
2114 2171
2115If your TLS server is a pure TLS server (e.g. HTTPS) that only speaks TLS, 2172If your TLS server is a pure TLS server (e.g. HTTPS) that only speaks TLS,
2116simply connect to it and then create the AnyEvent::Handle with the C<tls> 2173connect to it and then create the AnyEvent::Handle with the C<tls>
2117parameter: 2174parameter:
2118 2175
2119 tcp_connect $host, $port, sub { 2176 tcp_connect $host, $port, sub {
2120 my ($fh) = @_; 2177 my ($fh) = @_;
2121 2178
… …
2221 2278
2222=item * all members not documented here and not prefixed with an underscore 2279=item * all members not documented here and not prefixed with an underscore
2223are free to use in subclasses. 2280are free to use in subclasses.
2224 2281
2225Of course, new versions of AnyEvent::Handle may introduce more "public" 2282Of course, new versions of AnyEvent::Handle may introduce more "public"
2226member variables, but thats just life, at least it is documented. 2283member variables, but that's just life. At least it is documented.
2227 2284
2228=back 2285=back
2229 2286
2230=head1 AUTHOR 2287=head1 AUTHOR
2231 2288

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