--- AnyEvent/lib/AnyEvent/Handle.pm 2009/07/04 23:58:52 1.137 +++ AnyEvent/lib/AnyEvent/Handle.pm 2010/10/13 01:15:57 1.201 @@ -1,22 +1,6 @@ -package AnyEvent::Handle; - -no warnings; -use strict qw(subs vars); - -use AnyEvent (); -use AnyEvent::Util qw(WSAEWOULDBLOCK); -use Scalar::Util (); -use Carp (); -use Fcntl (); -use Errno qw(EAGAIN EINTR); - =head1 NAME -AnyEvent::Handle - non-blocking I/O on file handles via AnyEvent - -=cut - -our $VERSION = 4.452; +AnyEvent::Handle - non-blocking I/O on streaming handles via AnyEvent =head1 SYNOPSIS @@ -25,21 +9,22 @@ my $cv = AnyEvent->condvar; - my $handle = - AnyEvent::Handle->new ( - fh => \*STDIN, - on_eof => sub { - $cv->send; - }, - ); + my $hdl; $hdl = new AnyEvent::Handle + fh => \*STDIN, + on_error => sub { + my ($hdl, $fatal, $msg) = @_; + warn "got error $msg\n"; + $hdl->destroy; + $cv->send; + }; # send some request line - $handle->push_write ("getinfo\015\012"); + $hdl->push_write ("getinfo\015\012"); # read the response line - $handle->push_read (line => sub { - my ($handle, $line) = @_; - warn "read line <$line>\n"; + $hdl->push_read (line => sub { + my ($hdl, $line) = @_; + warn "got line <$line>\n"; $cv->send; }); @@ -47,84 +32,153 @@ =head1 DESCRIPTION -This module is a helper module to make it easier to do event-based I/O on -filehandles. For utility functions for doing non-blocking connects and accepts -on sockets see L. +This is a helper module to make it easier to do event-based I/O on +stream-based filehandles (sockets, pipes, and other stream things). The L tutorial contains some well-documented AnyEvent::Handle examples. -In the following, when the documentation refers to of "bytes" then this -means characters. As sysread and syswrite are used for all I/O, their +In the following, where the documentation refers to "bytes", it means +characters. As sysread and syswrite are used for all I/O, their treatment of characters applies to this module as well. +At the very minimum, you should specify C or C, and the +C callback. + All callbacks will be invoked with the handle object as their first argument. +=cut + +package AnyEvent::Handle; + +use Scalar::Util (); +use List::Util (); +use Carp (); +use Errno qw(EAGAIN EINTR); + +use AnyEvent (); BEGIN { AnyEvent::common_sense } +use AnyEvent::Util qw(WSAEWOULDBLOCK); + +our $VERSION = $AnyEvent::VERSION; + +sub _load_func($) { + my $func = $_[0]; + + unless (defined &$func) { + my $pkg = $func; + do { + $pkg =~ s/::[^:]+$// + or return; + eval "require $pkg"; + } until defined &$func; + } + + \&$func +} + =head1 METHODS =over 4 -=item $handle = B AnyEvent::TLS fh => $filehandle, key => value... +=item $handle = B AnyEvent::Handle fh => $filehandle, key => value... The constructor supports these arguments (all as C<< key => value >> pairs). =over 4 -=item fh => $filehandle [MANDATORY] +=item fh => $filehandle [C or C MANDATORY] The filehandle this L object will operate on. - NOTE: The filehandle will be set to non-blocking mode (using C) by the constructor and needs to stay in that mode. -=item on_eof => $cb->($handle) +=item connect => [$host, $service] [C or C MANDATORY] -Set the callback to be called when an end-of-file condition is detected, -i.e. in the case of a socket, when the other side has closed the -connection cleanly. +Try to connect to the specified host and service (port), using +C. The C<$host> additionally becomes the +default C. -For sockets, this just means that the other side has stopped sending data, -you can still try to write data, and, in fact, one can return from the EOF -callback and continue writing data, as only the read part has been shut -down. +You have to specify either this parameter, or C, above. -While not mandatory, it is I recommended to set an EOF callback, -otherwise you might end up with a closed socket while you are still -waiting for data. +It is possible to push requests on the read and write queues, and modify +properties of the stream, even while AnyEvent::Handle is connecting. -If an EOF condition has been detected but no C callback has been -set, then a fatal error will be raised with C<$!> set to <0>. +When this parameter is specified, then the C, +C and C callbacks will be called under the +appropriate circumstances: + +=over 4 + +=item on_prepare => $cb->($handle) + +This (rarely used) callback is called before a new connection is +attempted, but after the file handle has been created. It could be used to +prepare the file handle with parameters required for the actual connect +(as opposed to settings that can be changed when the connection is already +established). + +The return value of this callback should be the connect timeout value in +seconds (or C<0>, or C, or the empty list, to indicate that the +default timeout is to be used). + +=item on_connect => $cb->($handle, $host, $port, $retry->()) + +This callback is called when a connection has been successfully established. + +The peer's numeric host and port (the socket peername) are passed as +parameters, together with a retry callback. + +If, for some reason, the handle is not acceptable, calling C<$retry> +will continue with the next connection target (in case of multi-homed +hosts or SRV records there can be multiple connection endpoints). At the +time it is called the read and write queues, eof status, tls status and +similar properties of the handle will have been reset. + +In most cases, you should ignore the C<$retry> parameter. + +=item on_connect_error => $cb->($handle, $message) + +This callback is called when the connection could not be +established. C<$!> will contain the relevant error code, and C<$message> a +message describing it (usually the same as C<"$!">). + +If this callback isn't specified, then C will be called with a +fatal error instead. + +=back =item on_error => $cb->($handle, $fatal, $message) This is the error callback, which is called when, well, some error occured, such as not being able to resolve the hostname, failure to -connect or a read error. +connect, or a read error. Some errors are fatal (which is indicated by C<$fatal> being true). On -fatal errors the handle object will be shut down and will not be usable -(but you are free to look at the current C<< ->rbuf >>). Examples of fatal -errors are an EOF condition with active (but unsatisifable) read watchers -(C) or I/O errors. +fatal errors the handle object will be destroyed (by a call to C<< -> +destroy >>) after invoking the error callback (which means you are free to +examine the handle object). Examples of fatal errors are an EOF condition +with active (but unsatisifable) read watchers (C) or I/O errors. In +cases where the other side can close the connection at will, it is +often easiest to not report C errors in this callback. AnyEvent::Handle tries to find an appropriate error code for you to check against, but in some cases (TLS errors), this does not work well. It is recommended to always output the C<$message> argument in human-readable error messages (it's usually the same as C<"$!">). -Non-fatal errors can be retried by simply returning, but it is recommended +Non-fatal errors can be retried by returning, but it is recommended to simply ignore this parameter and instead abondon the handle object when this callback is invoked. Examples of non-fatal errors are timeouts C) or badly-formatted data (C). -On callback entrance, the value of C<$!> contains the operating system -error code (or C, C, C, C or +On entry to the callback, the value of C<$!> contains the operating +system error code (or C, C, C, C or C). While not mandatory, it is I recommended to set this callback, as -you will not be notified of errors otherwise. The default simply calls +you will not be notified of errors otherwise. The default just calls C. =item on_read => $cb->($handle) @@ -135,19 +189,43 @@ read buffer). To access (and remove data from) the read buffer, use the C<< ->rbuf >> -method or access the C<$handle->{rbuf}> member directly. Note that you +method or access the C<< $handle->{rbuf} >> member directly. Note that you must not enlarge or modify the read buffer, you can only remove data at the beginning from it. -When an EOF condition is detected then AnyEvent::Handle will first try to +You can also call C<< ->push_read (...) >> or any other function that +modifies the read queue. Or do both. Or ... + +When an EOF condition is detected, AnyEvent::Handle will first try to feed all the remaining data to the queued callbacks and C before calling the C callback. If no progress can be made, then a fatal error will be raised (with C<$!> set to C). +Note that, unlike requests in the read queue, an C callback +doesn't mean you I some data: if there is an EOF and there +are outstanding read requests then an error will be flagged. With an +C callback, the C callback will be invoked. + +=item on_eof => $cb->($handle) + +Set the callback to be called when an end-of-file condition is detected, +i.e. in the case of a socket, when the other side has closed the +connection cleanly, and there are no outstanding read requests in the +queue (if there are read requests, then an EOF counts as an unexpected +connection close and will be flagged as an error). + +For sockets, this just means that the other side has stopped sending data, +you can still try to write data, and, in fact, one can return from the EOF +callback and continue writing data, as only the read part has been shut +down. + +If an EOF condition has been detected but no C callback has been +set, then a fatal error will be raised with C<$!> set to <0>. + =item on_drain => $cb->($handle) This sets the callback that is called when the write buffer becomes empty -(or when the callback is set and the buffer is empty already). +(or immediately if the buffer is empty already). To append to the write buffer, use the C<< ->push_write >> method. @@ -159,14 +237,25 @@ =item timeout => $fractional_seconds -If non-zero, then this enables an "inactivity" timeout: whenever this many -seconds pass without a successful read or write on the underlying file -handle, the C callback will be invoked (and if that one is -missing, a non-fatal C error will be raised). +=item rtimeout => $fractional_seconds + +=item wtimeout => $fractional_seconds -Note that timeout processing is also active when you currently do not have +If non-zero, then these enables an "inactivity" timeout: whenever this +many seconds pass without a successful read or write on the underlying +file handle (or a call to C), the C callback +will be invoked (and if that one is missing, a non-fatal C +error will be raised). + +There are three variants of the timeouts that work independently +of each other, for both read and write, just read, and just write: +C, C and C, with corresponding callbacks +C, C and C, and reset functions +C, C, and C. + +Note that timeout processing is active even when you do not have any outstanding read or write requests: If you plan to keep the connection -idle then you should disable the timout temporarily or ignore the timeout +idle then you should disable the timeout temporarily or ignore the timeout in the C callback, in which case AnyEvent::Handle will simply restart the timeout. @@ -192,14 +281,14 @@ =item autocork => -When disabled (the default), then C will try to immediately -write the data to the handle, if possible. This avoids having to register +When disabled (the default), C will try to immediately +write the data to the handle if possible. This avoids having to register a write watcher and wait for the next event loop iteration, but can be inefficient if you write multiple small chunks (on the wire, this disadvantage is usually avoided by your kernel's nagle algorithm, see C, but this option can save costly syscalls). -When enabled, then writes will always be queued till the next event loop +When enabled, writes will always be queued till the next event loop iteration. This is efficient when you do many small writes per iteration, but less efficient when you do a single write only per iteration (or when the write buffer often is full). It also increases write latency. @@ -213,19 +302,51 @@ In some situations you want as low a delay as possible, which can be accomplishd by setting this option to a true value. -The default is your opertaing system's default behaviour (most likely -enabled), this option explicitly enables or disables it, if possible. +The default is your operating system's default behaviour (most likely +enabled). This option explicitly enables or disables it, if possible. + +=item keepalive => + +Enables (default disable) the SO_KEEPALIVE option on the stream socket: +normally, TCP connections have no time-out once established, so TCP +connections, once established, can stay alive forever even when the other +side has long gone. TCP keepalives are a cheap way to take down long-lived +TCP connections when the other side becomes unreachable. While the default +is OS-dependent, TCP keepalives usually kick in after around two hours, +and, if the other side doesn't reply, take down the TCP connection some 10 +to 15 minutes later. + +It is harmless to specify this option for file handles that do not support +keepalives, and enabling it on connections that are potentially long-lived +is usually a good idea. + +=item oobinline => + +BSD majorly fucked up the implementation of TCP urgent data. The result +is that almost no OS implements TCP according to the specs, and every OS +implements it slightly differently. + +If you want to handle TCP urgent data, then setting this flag (the default +is enabled) gives you the most portable way of getting urgent data, by +putting it into the stream. + +Since BSD emulation of OOB data on top of TCP's urgent data can have +security implications, AnyEvent::Handle sets this flag automatically +unless explicitly specified. Note that setting this flag after +establishing a connection I be a bit too late (data loss could +already have occured on BSD systems), but at least it will protect you +from most attacks. =item read_size => -The default read block size (the amount of bytes this module will +The default read block size (the number of bytes this module will try to read during each loop iteration, which affects memory requirements). Default: C<8192>. =item low_water_mark => -Sets the amount of bytes (default: C<0>) that make up an "empty" write -buffer: If the write reaches this size or gets even samller it is +Sets the number of bytes (default: C<0>) that make up an "empty" write +buffer: If the buffer reaches this size or gets even samller it is considered empty. Sometimes it can be beneficial (for performance reasons) to add data to @@ -235,7 +356,7 @@ =item linger => -If non-zero (default: C<3600>), then the destructor of the +If this is non-zero (default: C<3600>), the destructor of the AnyEvent::Handle object will check whether there is still outstanding write data and will install a watcher that will write this data to the socket. No errors will be reported (this mostly matches how the operating @@ -251,12 +372,14 @@ (I IDN!) used to create the connection, rarely the IP address. Apart from being useful in error messages, this string is also used in TLS -common name verification (see C in L). +peername verification (see C in L). This +verification will be skipped when C is not specified or is +C. =item tls => "accept" | "connect" | Net::SSLeay::SSL object When this parameter is given, it enables TLS (SSL) mode, that means -AnyEvent will start a TLS handshake as soon as the conenction has been +AnyEvent will start a TLS handshake as soon as the connection has been established and will transparently encrypt/decrypt data afterwards. All TLS protocol errors will be signalled as C, with an @@ -286,7 +409,7 @@ happens when one uses a stylish C<< tls => 1 >> and is surprised about the segmentation fault. -See the C<< ->starttls >> method for when need to start TLS negotiation later. +Use the C<< ->starttls >> method if you need to start TLS negotiation later. =item tls_ctx => $anyevent_tls @@ -298,6 +421,38 @@ => value >> pairs. Those will be passed to L to create a new TLS context object. +=item on_starttls => $cb->($handle, $success[, $error_message]) + +This callback will be invoked when the TLS/SSL handshake has finished. If +C<$success> is true, then the TLS handshake succeeded, otherwise it failed +(C will not be called in this case). + +The session in C<< $handle->{tls} >> can still be examined in this +callback, even when the handshake was not successful. + +TLS handshake failures will not cause C to be invoked when this +callback is in effect, instead, the error message will be passed to C. + +Without this callback, handshake failures lead to C being +called as usual. + +Note that you cannot just call C again in this callback. If you +need to do that, start an zero-second timer instead whose callback can +then call C<< ->starttls >> again. + +=item on_stoptls => $cb->($handle) + +When a SSLv3/TLS shutdown/close notify/EOF is detected and this callback is +set, then it will be invoked after freeing the TLS session. If it is not, +then a TLS shutdown condition will be treated like a normal EOF condition +on the handle. + +The session in C<< $handle->{tls} >> can still be examined in this +callback. + +This callback will only be called on TLS shutdowns, not when the +underlying handle signals EOF. + =item json => JSON or JSON::XS object This is the json coder object used by the C read and write types. @@ -317,47 +472,113 @@ my $class = shift; my $self = bless { @_ }, $class; - $self->{fh} or Carp::croak "mandatory argument fh is missing"; + if ($self->{fh}) { + $self->_start; + return unless $self->{fh}; # could be gone by now + + } elsif ($self->{connect}) { + require AnyEvent::Socket; + + $self->{peername} = $self->{connect}[0] + unless exists $self->{peername}; + + $self->{_skip_drain_rbuf} = 1; + + { + Scalar::Util::weaken (my $self = $self); + + $self->{_connect} = + AnyEvent::Socket::tcp_connect ( + $self->{connect}[0], + $self->{connect}[1], + sub { + my ($fh, $host, $port, $retry) = @_; + + if ($fh) { + $self->{fh} = $fh; + + delete $self->{_skip_drain_rbuf}; + $self->_start; + + $self->{on_connect} + and $self->{on_connect}($self, $host, $port, sub { + delete @$self{qw(fh _tw _rtw _wtw _ww _rw _eof _queue rbuf _wbuf tls _tls_rbuf _tls_wbuf)}; + $self->{_skip_drain_rbuf} = 1; + &$retry; + }); + + } else { + if ($self->{on_connect_error}) { + $self->{on_connect_error}($self, "$!"); + $self->destroy; + } else { + $self->_error ($!, 1); + } + } + }, + sub { + local $self->{fh} = $_[0]; + + $self->{on_prepare} + ? $self->{on_prepare}->($self) + : () + } + ); + } + + } else { + Carp::croak "AnyEvent::Handle: either an existing fh or the connect parameter must be specified"; + } - AnyEvent::Util::fh_nonblocking $self->{fh}, 1; + $self +} - $self->{_activity} = AnyEvent->now; - $self->_timeout; +sub _start { + my ($self) = @_; - $self->no_delay (delete $self->{no_delay}) if exists $self->{no_delay}; + # too many clueless people try to use udp and similar sockets + # with AnyEvent::Handle, do them a favour. + my $type = getsockopt $self->{fh}, Socket::SOL_SOCKET (), Socket::SO_TYPE (); + Carp::croak "AnyEvent::Handle: only stream sockets supported, anything else will NOT work!" + if Socket::SOCK_STREAM () != (unpack "I", $type) && defined $type; - $self->starttls (delete $self->{tls}, delete $self->{tls_ctx}) - if $self->{tls}; + AnyEvent::Util::fh_nonblocking $self->{fh}, 1; - $self->on_drain (delete $self->{on_drain}) if exists $self->{on_drain}; + $self->{_activity} = + $self->{_ractivity} = + $self->{_wactivity} = AE::now; - $self->start_read - if $self->{on_read}; + $self->timeout (delete $self->{timeout} ) if $self->{timeout}; + $self->rtimeout (delete $self->{rtimeout} ) if $self->{rtimeout}; + $self->wtimeout (delete $self->{wtimeout} ) if $self->{wtimeout}; - $self->{fh} && $self -} + $self->no_delay (delete $self->{no_delay} ) if exists $self->{no_delay} && $self->{no_delay}; + $self->keepalive (delete $self->{keepalive}) if exists $self->{keepalive} && $self->{keepalive}; -sub _shutdown { - my ($self) = @_; + $self->oobinline (exists $self->{oobinline} ? delete $self->{oobinline} : 1); - delete @$self{qw(_tw _rw _ww fh wbuf on_read _queue)}; - $self->{_eof} = 1; # tell starttls et. al to stop trying + $self->starttls (delete $self->{tls}, delete $self->{tls_ctx}) + if $self->{tls}; - &_freetls; + $self->on_drain (delete $self->{on_drain} ) if $self->{on_drain}; + + $self->start_read + if $self->{on_read} || @{ $self->{_queue} }; + + $self->_drain_wbuf; } sub _error { my ($self, $errno, $fatal, $message) = @_; - $self->_shutdown - if $fatal; - $! = $errno; $message ||= "$!"; if ($self->{on_error}) { $self->{on_error}($self, $fatal, $message); - } elsif ($self->{fh}) { + $self->destroy if $fatal; + } elsif ($self->{fh} || $self->{connect}) { + $self->destroy; Carp::croak "AnyEvent::Handle uncaught error: $message"; } } @@ -392,15 +613,17 @@ =item $handle->on_timeout ($cb) -Replace the current C callback, or disables the callback (but -not the timeout) if C<$cb> = C. See the C constructor -argument and method. +=item $handle->on_rtimeout ($cb) + +=item $handle->on_wtimeout ($cb) + +Replace the current C, C or C +callback, or disables the callback (but not the timeout) if C<$cb> = +C. See the C constructor argument and method. =cut -sub on_timeout { - $_[0]{on_timeout} = $_[1]; -} +# see below =item $handle->autocork ($boolean) @@ -423,64 +646,177 @@ sub no_delay { $_[0]{no_delay} = $_[1]; + setsockopt $_[0]{fh}, Socket::IPPROTO_TCP (), Socket::TCP_NODELAY (), int $_[1] + if $_[0]{fh}; +} + +=item $handle->keepalive ($boolean) + +Enables or disables the C setting (see constructor argument of +the same name for details). + +=cut + +sub keepalive { + $_[0]{keepalive} = $_[1]; + + eval { + local $SIG{__DIE__}; + setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_KEEPALIVE (), int $_[1] + if $_[0]{fh}; + }; +} + +=item $handle->oobinline ($boolean) + +Enables or disables the C setting (see constructor argument of +the same name for details). + +=cut + +sub oobinline { + $_[0]{oobinline} = $_[1]; + eval { local $SIG{__DIE__}; - setsockopt $_[0]{fh}, &Socket::IPPROTO_TCP, &Socket::TCP_NODELAY, int $_[1]; + setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_OOBINLINE (), int $_[1] + if $_[0]{fh}; }; } +=item $handle->keepalive ($boolean) + +Enables or disables the C setting (see constructor argument of +the same name for details). + +=cut + +sub keepalive { + $_[0]{keepalive} = $_[1]; + + eval { + local $SIG{__DIE__}; + setsockopt $_[0]{fh}, Socket::SOL_SOCKET (), Socket::SO_KEEPALIVE (), int $_[1] + if $_[0]{fh}; + }; +} + +=item $handle->on_starttls ($cb) + +Replace the current C callback (see the C constructor argument). + +=cut + +sub on_starttls { + $_[0]{on_starttls} = $_[1]; +} + +=item $handle->on_stoptls ($cb) + +Replace the current C callback (see the C constructor argument). + +=cut + +sub on_stoptls { + $_[0]{on_stoptls} = $_[1]; +} + +=item $handle->rbuf_max ($max_octets) + +Configures the C setting (C disables it). + +=cut + +sub rbuf_max { + $_[0]{rbuf_max} = $_[1]; +} + ############################################################################# =item $handle->timeout ($seconds) +=item $handle->rtimeout ($seconds) + +=item $handle->wtimeout ($seconds) + Configures (or disables) the inactivity timeout. +=item $handle->timeout_reset + +=item $handle->rtimeout_reset + +=item $handle->wtimeout_reset + +Reset the activity timeout, as if data was received or sent. + +These methods are cheap to call. + =cut -sub timeout { - my ($self, $timeout) = @_; +for my $dir ("", "r", "w") { + my $timeout = "${dir}timeout"; + my $tw = "_${dir}tw"; + my $on_timeout = "on_${dir}timeout"; + my $activity = "_${dir}activity"; + my $cb; - $self->{timeout} = $timeout; - $self->_timeout; -} + *$on_timeout = sub { + $_[0]{$on_timeout} = $_[1]; + }; -# reset the timeout watcher, as neccessary -# also check for time-outs -sub _timeout { - my ($self) = @_; + *$timeout = sub { + my ($self, $new_value) = @_; - if ($self->{timeout}) { - my $NOW = AnyEvent->now; + $new_value >= 0 + or Carp::croak "AnyEvent::Handle->$timeout called with negative timeout ($new_value), caught"; - # when would the timeout trigger? - my $after = $self->{_activity} + $self->{timeout} - $NOW; + $self->{$timeout} = $new_value; + delete $self->{$tw}; &$cb; + }; - # now or in the past already? - if ($after <= 0) { - $self->{_activity} = $NOW; + *{"${dir}timeout_reset"} = sub { + $_[0]{$activity} = AE::now; + }; - if ($self->{on_timeout}) { - $self->{on_timeout}($self); - } else { - $self->_error (&Errno::ETIMEDOUT); - } + # main workhorse: + # reset the timeout watcher, as neccessary + # also check for time-outs + $cb = sub { + my ($self) = @_; + + if ($self->{$timeout} && $self->{fh}) { + my $NOW = AE::now; + + # when would the timeout trigger? + my $after = $self->{$activity} + $self->{$timeout} - $NOW; + + # now or in the past already? + if ($after <= 0) { + $self->{$activity} = $NOW; - # callback could have changed timeout value, optimise - return unless $self->{timeout}; + if ($self->{$on_timeout}) { + $self->{$on_timeout}($self); + } else { + $self->_error (Errno::ETIMEDOUT); + } - # calculate new after - $after = $self->{timeout}; - } + # callback could have changed timeout value, optimise + return unless $self->{$timeout}; - Scalar::Util::weaken $self; - return unless $self; # ->error could have destroyed $self + # calculate new after + $after = $self->{$timeout}; + } - $self->{_tw} ||= AnyEvent->timer (after => $after, cb => sub { - delete $self->{_tw}; - $self->_timeout; - }); - } else { - delete $self->{_tw}; + Scalar::Util::weaken $self; + return unless $self; # ->error could have destroyed $self + + $self->{$tw} ||= AE::timer $after, 0, sub { + delete $self->{$tw}; + $cb->($self); + }; + } else { + delete $self->{$tw}; + } } } @@ -506,6 +842,9 @@ Sets the C callback or clears it (see the description of C in the constructor). +This method may invoke callbacks (and therefore the handle might be +destroyed after it returns). + =cut sub on_drain { @@ -523,6 +862,9 @@ want (only limited by the available memory), as C buffers it independently of the kernel. +This method may invoke callbacks (and therefore the handle might be +destroyed after it returns). + =cut sub _drain_wbuf { @@ -535,10 +877,10 @@ my $cb = sub { my $len = syswrite $self->{fh}, $self->{wbuf}; - if ($len >= 0) { + if (defined $len) { substr $self->{wbuf}, 0, $len, ""; - $self->{_activity} = AnyEvent->now; + $self->{_activity} = $self->{_wactivity} = AE::now; $self->{on_drain}($self) if $self->{low_water_mark} >= (length $self->{wbuf}) + (length $self->{_tls_wbuf}) @@ -554,13 +896,14 @@ $cb->() unless $self->{autocork}; # if still data left in wbuf, we need to poll - $self->{_ww} = AnyEvent->io (fh => $self->{fh}, poll => "w", cb => $cb) + $self->{_ww} = AE::io $self->{fh}, 1, $cb if length $self->{wbuf}; }; } our %WH; +# deprecated sub register_write_type($$) { $WH{$_[0]} = $_[1]; } @@ -571,24 +914,30 @@ if (@_ > 1) { my $type = shift; - @_ = ($WH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_write") + @_ = ($WH{$type} ||= _load_func "$type\::anyevent_write_type" + or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::push_write") ->($self, @_); } - if ($self->{tls}) { - $self->{_tls_wbuf} .= $_[0]; + # we downgrade here to avoid hard-to-track-down bugs, + # and diagnose the problem earlier and better. - &_dotls ($self); + if ($self->{tls}) { + utf8::downgrade $self->{_tls_wbuf} .= $_[0]; + &_dotls ($self) if $self->{fh}; } else { - $self->{wbuf} .= $_[0]; - $self->_drain_wbuf; + utf8::downgrade $self->{wbuf} .= $_[0]; + $self->_drain_wbuf if $self->{fh}; } } =item $handle->push_write (type => @args) -Instead of formatting your data yourself, you can also let this module do -the job by specifying a type and type-specific arguments. +Instead of formatting your data yourself, you can also let this module +do the job by specifying a type and type-specific arguments. You +can also specify the (fully qualified) name of a package, in which +case AnyEvent tries to load the package and then expects to find the +C function inside (see "custom write types", below). Predefined types are (if you have ideas for additional types, feel free to drop by and tell us): @@ -655,13 +1004,17 @@ =cut +sub json_coder() { + eval { require JSON::XS; JSON::XS->new->utf8 } + || do { require JSON; JSON->new->utf8 } +} + register_write_type json => sub { my ($self, $ref) = @_; - require JSON; + my $json = $self->{json} ||= json_coder; - $self->{json} ? $self->{json}->encode ($ref) - : JSON::encode_json ($ref) + $json->encode ($ref) }; =item storable => $reference @@ -685,8 +1038,9 @@ Sometimes you know you want to close the socket after writing your data before it was actually written. One way to do that is to replace your -C handler by a callback that shuts down the socket. This method -is a shorthand for just that, and replaces the C callback with: +C handler by a callback that shuts down the socket (and set +C to C<0>). This method is a shorthand for just that, and +replaces the C callback with: sub { shutdown $_[0]{fh}, 1 } # for push_shutdown @@ -696,23 +1050,49 @@ You can rely on the normal read queue and C handling afterwards. This is the cleanest way to close a connection. +This method may invoke callbacks (and therefore the handle might be +destroyed after it returns). + =cut sub push_shutdown { - $_[0]->{on_drain} = sub { shutdown $_[0]{fh}, 1 }; + my ($self) = @_; + + delete $self->{low_water_mark}; + $self->on_drain (sub { shutdown $_[0]{fh}, 1 }); } -=item AnyEvent::Handle::register_write_type type => $coderef->($handle, @args) +=item custom write types - Package::anyevent_write_type $handle, @args -This function (not method) lets you add your own types to C. -Whenever the given C is used, C will invoke the code -reference with the handle object and the remaining arguments. +Instead of one of the predefined types, you can also specify the name of +a package. AnyEvent will try to load the package and then expects to find +a function named C inside. If it isn't found, it +progressively tries to load the parent package until it either finds the +function (good) or runs out of packages (bad). -The code reference is supposed to return a single octet string that will -be appended to the write buffer. +Whenever the given C is used, C will the function with +the handle object and the remaining arguments. -Note that this is a function, and all types registered this way will be -global, so try to use unique names. +The function is supposed to return a single octet string that will be +appended to the write buffer, so you cna mentally treat this function as a +"arguments to on-the-wire-format" converter. + +Example: implement a custom write type C that joins the remaining +arguments using the first one. + + $handle->push_write (My::Type => " ", 1,2,3); + + # uses the following package, which can be defined in the "My::Type" or in + # the "My" modules to be auto-loaded, or just about anywhere when the + # My::Type::anyevent_write_type is defined before invoking it. + + package My::Type; + + sub anyevent_write_type { + my ($handle, $delim, @args) = @_; + + join $delim, @args + } =cut @@ -731,13 +1111,14 @@ In the simple case, you just install an C callback and whenever new data arrives, it will be called. You can then remove some data (if -enough is there) from the read buffer (C<< $handle->rbuf >>). Or you cna +enough is there) from the read buffer (C<< $handle->rbuf >>). Or you can leave the data there if you want to accumulate more (e.g. when only a -partial message has been received so far). +partial message has been received so far), or change the read queue with +e.g. C. In the more complex case, you want to queue multiple callbacks. In this case, AnyEvent::Handle will call the first queued callback each time new -data arrives (also the first time it is queued) and removes it when it has +data arrives (also the first time it is queued) and remove it when it has done its job (see C, below). This way you can, for example, push three line-reads, followed by reading @@ -804,28 +1185,24 @@ sub _drain_rbuf { my ($self) = @_; - local $self->{_in_drain} = 1; - - if ( - defined $self->{rbuf_max} - && $self->{rbuf_max} < length $self->{rbuf} - ) { - $self->_error (&Errno::ENOSPC, 1), return; - } + # avoid recursion + return if $self->{_skip_drain_rbuf}; + local $self->{_skip_drain_rbuf} = 1; while () { # we need to use a separate tls read buffer, as we must not receive data while # we are draining the buffer, and this can only happen with TLS. - $self->{rbuf} .= delete $self->{_tls_rbuf} if exists $self->{_tls_rbuf}; + $self->{rbuf} .= delete $self->{_tls_rbuf} + if exists $self->{_tls_rbuf}; my $len = length $self->{rbuf}; if (my $cb = shift @{ $self->{_queue} }) { unless ($cb->($self)) { - if ($self->{_eof}) { - # no progress can be made (not enough data and no data forthcoming) - $self->_error (&Errno::EPIPE, 1), return; - } + # no progress can be made + # (not enough data and no data forthcoming) + $self->_error (Errno::EPIPE, 1), return + if $self->{_eof}; unshift @{ $self->{_queue} }, $cb; last; @@ -842,7 +1219,7 @@ ) { # no further data will arrive # so no progress can be made - $self->_error (&Errno::EPIPE, 1), return + $self->_error (Errno::EPIPE, 1), return if $self->{_eof}; last; # more data might arrive @@ -855,11 +1232,18 @@ } if ($self->{_eof}) { - if ($self->{on_eof}) { - $self->{on_eof}($self) - } else { - $self->_error (0, 1); - } + $self->{on_eof} + ? $self->{on_eof}($self) + : $self->_error (0, 1, "Unexpected end-of-file"); + + return; + } + + if ( + defined $self->{rbuf_max} + && $self->{rbuf_max} < length $self->{rbuf} + ) { + $self->_error (Errno::ENOSPC, 1), return; } # may need to restart read watcher @@ -875,28 +1259,32 @@ the new callback is C). See the description of C in the constructor. +This method may invoke callbacks (and therefore the handle might be +destroyed after it returns). + =cut sub on_read { my ($self, $cb) = @_; $self->{on_read} = $cb; - $self->_drain_rbuf if $cb && !$self->{_in_drain}; + $self->_drain_rbuf if $cb; } =item $handle->rbuf -Returns the read buffer (as a modifiable lvalue). - -You can access the read buffer directly as the C<< ->{rbuf} >> -member, if you want. However, the only operation allowed on the -read buffer (apart from looking at it) is removing data from its -beginning. Otherwise modifying or appending to it is not allowed and will -lead to hard-to-track-down bugs. - -NOTE: The read buffer should only be used or modified if the C, -C or C methods are used. The other read methods -automatically manage the read buffer. +Returns the read buffer (as a modifiable lvalue). You can also access the +read buffer directly as the C<< ->{rbuf} >> member, if you want (this is +much faster, and no less clean). + +The only operation allowed on the read buffer (apart from looking at it) +is removing data from its beginning. Otherwise modifying or appending to +it is not allowed and will lead to hard-to-track-down bugs. + +NOTE: The read buffer should only be used or modified in the C +callback or when C or C are used with a single +callback (i.e. untyped). Typed C and C methods +will manage the read buffer on their own. =cut @@ -923,6 +1311,9 @@ interested in (which can be none at all) and return a true value. After returning true, it will be removed from the queue. +These methods may invoke callbacks (and therefore the handle might be +destroyed after it returns). + =cut our %RH; @@ -938,12 +1329,13 @@ if (@_) { my $type = shift; - $cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::push_read") + $cb = ($RH{$type} ||= _load_func "$type\::anyevent_read_type" + or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::push_read") ->($self, $cb, @_); } push @{ $self->{_queue} }, $cb; - $self->_drain_rbuf unless $self->{_in_drain}; + $self->_drain_rbuf; } sub unshift_read { @@ -953,13 +1345,13 @@ if (@_) { my $type = shift; - $cb = ($RH{$type} or Carp::croak "unsupported type passed to AnyEvent::Handle::unshift_read") + $cb = ($RH{$type} ||= _load_func "$type\::anyevent_read_type" + or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::unshift_read") ->($self, $cb, @_); } - unshift @{ $self->{_queue} }, $cb; - $self->_drain_rbuf unless $self->{_in_drain}; + $self->_drain_rbuf; } =item $handle->push_read (type => @args, $cb) @@ -968,7 +1360,9 @@ Instead of providing a callback that parses the data itself you can chose between a number of predefined parsing formats, for chunks of data, lines -etc. +etc. You can also specify the (fully qualified) name of a package, in +which case AnyEvent tries to load the package and then expects to find the +C function inside (see "custom read types", below). Predefined types are (if you have ideas for additional types, feel free to drop by and tell us): @@ -1070,10 +1464,10 @@ unconditionally. This is useful to skip large amounts of data that you know cannot be matched, so that the C<$accept> or C<$reject> regex do not have to start matching from the beginning. This is purely an optimisation -and is usually worth only when you expect more than a few kilobytes. +and is usually worth it only when you expect more than a few kilobytes. Example: expect a http header, which ends at C<\015\012\015\012>. Since we -expect the header to be very large (it isn't in practise, but...), we use +expect the header to be very large (it isn't in practice, but...), we use a skip regex to skip initial portions. The skip regex is tricky in that it only accepts something not ending in either \015 or \012, as these are required for the accept regex. @@ -1102,7 +1496,7 @@ # reject if ($reject && $$rbuf =~ $reject) { - $self->_error (&Errno::EBADMSG); + $self->_error (Errno::EBADMSG); } # skip @@ -1128,7 +1522,7 @@ sub { unless ($_[0]{rbuf} =~ s/^(0|[1-9][0-9]*)://) { if ($_[0]{rbuf} =~ /[^0-9]/) { - $self->_error (&Errno::EBADMSG); + $self->_error (Errno::EBADMSG); } return; } @@ -1141,7 +1535,7 @@ if ($_[1] eq ",") { $cb->($_[0], $string); } else { - $self->_error (&Errno::EBADMSG); + $self->_error (Errno::EBADMSG); } }); }); @@ -1218,9 +1612,7 @@ register_read_type json => sub { my ($self, $cb) = @_; - my $json = $self->{json} ||= - eval { require JSON::XS; JSON::XS->new->utf8 } - || do { require JSON; JSON->new->utf8 }; + my $json = $self->{json} ||= json_coder; my $data; my $rbuf = \$self->{rbuf}; @@ -1241,7 +1633,7 @@ $self->{rbuf} = $json->incr_text; $json->incr_text = ""; - $self->_error (&Errno::EBADMSG); + $self->_error (Errno::EBADMSG); () } else { @@ -1288,7 +1680,7 @@ if (my $ref = eval { Storable::thaw ($_[1]) }) { $cb->($_[0], $ref); } else { - $self->_error (&Errno::EBADMSG); + $self->_error (Errno::EBADMSG); } }); } @@ -1299,25 +1691,28 @@ =back -=item AnyEvent::Handle::register_read_type type => $coderef->($handle, $cb, @args) - -This function (not method) lets you add your own types to C. - -Whenever the given C is used, C will invoke the code -reference with the handle object, the callback and the remaining -arguments. +=item custom read types - Package::anyevent_read_type $handle, $cb, @args -The code reference is supposed to return a callback (usually a closure) -that works as a plain read callback (see C<< ->push_read ($cb) >>). +Instead of one of the predefined types, you can also specify the name +of a package. AnyEvent will try to load the package and then expects to +find a function named C inside. If it isn't found, it +progressively tries to load the parent package until it either finds the +function (good) or runs out of packages (bad). + +Whenever this type is used, C will invoke the function with the +handle object, the original callback and the remaining arguments. + +The function is supposed to return a callback (usually a closure) that +works as a plain read callback (see C<< ->push_read ($cb) >>), so you can +mentally treat the function as a "configurable read type to read callback" +converter. + +It should invoke the original callback when it is done reading (remember +to pass C<$handle> as first argument as all other callbacks do that, +although there is no strict requirement on this). -It should invoke the passed callback when it is done reading (remember to -pass C<$handle> as first argument as all other callbacks do that). - -Note that this is a function, and all types registered this way will be -global, so try to use unique names. - -For examples, see the source of this module (F, -search for C)). +For examples, see the source of this module (F, search for C)). =item $handle->stop_read @@ -1347,39 +1742,38 @@ sub start_read { my ($self) = @_; - unless ($self->{_rw} || $self->{_eof}) { + unless ($self->{_rw} || $self->{_eof} || !$self->{fh}) { Scalar::Util::weaken $self; - $self->{_rw} = AnyEvent->io (fh => $self->{fh}, poll => "r", cb => sub { + $self->{_rw} = AE::io $self->{fh}, 0, sub { my $rbuf = \($self->{tls} ? my $buf : $self->{rbuf}); my $len = sysread $self->{fh}, $$rbuf, $self->{read_size} || 8192, length $$rbuf; if ($len > 0) { - $self->{_activity} = AnyEvent->now; + $self->{_activity} = $self->{_ractivity} = AE::now; if ($self->{tls}) { Net::SSLeay::BIO_write ($self->{_rbio}, $$rbuf); &_dotls ($self); } else { - $self->_drain_rbuf unless $self->{_in_drain}; + $self->_drain_rbuf; } } elsif (defined $len) { delete $self->{_rw}; $self->{_eof} = 1; - $self->_drain_rbuf unless $self->{_in_drain}; + $self->_drain_rbuf; } elsif ($! != EAGAIN && $! != EINTR && $! != WSAEWOULDBLOCK) { return $self->_error ($!, 1); } - }); + }; } } our $ERROR_SYSCALL; our $ERROR_WANT_READ; -our $ERROR_ZERO_RETURN; sub _tls_error { my ($self, $err) = @_; @@ -1392,7 +1786,13 @@ # reduce error string to look less scary $err =~ s/^error:[0-9a-fA-F]{8}:[^:]+:([^:]+):/\L$1: /; - $self->_error (&Errno::EPROTO, 1, $err); + if ($self->{_on_starttls}) { + (delete $self->{_on_starttls})->($self, undef, $err); + &_freetls; + } else { + &_freetls; + $self->_error (Errno::EPROTO, 1, $err); + } } # poll the write BIO and send the data if applicable @@ -1413,33 +1813,44 @@ $tmp = Net::SSLeay::get_error ($self->{tls}, $tmp); return $self->_tls_error ($tmp) if $tmp != $ERROR_WANT_READ - && ($tmp != $ERROR_SYSCALL || $!) - && $tmp != $ERROR_ZERO_RETURN; + && ($tmp != $ERROR_SYSCALL || $!); } while (defined ($tmp = Net::SSLeay::read ($self->{tls}))) { unless (length $tmp) { - # let's treat SSL-eof as we treat normal EOF - delete $self->{_rw}; - $self->{_eof} = 1; + $self->{_on_starttls} + and (delete $self->{_on_starttls})->($self, undef, "EOF during handshake"); # ??? &_freetls; + + if ($self->{on_stoptls}) { + $self->{on_stoptls}($self); + return; + } else { + # let's treat SSL-eof as we treat normal EOF + delete $self->{_rw}; + $self->{_eof} = 1; + } } $self->{_tls_rbuf} .= $tmp; - $self->_drain_rbuf unless $self->{_in_drain}; + $self->_drain_rbuf; $self->{tls} or return; # tls session might have gone away in callback } $tmp = Net::SSLeay::get_error ($self->{tls}, -1); return $self->_tls_error ($tmp) if $tmp != $ERROR_WANT_READ - && ($tmp != $ERROR_SYSCALL || $!) - && $tmp != $ERROR_ZERO_RETURN; + && ($tmp != $ERROR_SYSCALL || $!); while (length ($tmp = Net::SSLeay::BIO_read ($self->{_wbio}))) { $self->{wbuf} .= $tmp; $self->_drain_wbuf; + $self->{tls} or return; # tls session might have gone away in callback } + + $self->{_on_starttls} + and Net::SSLeay::state ($self->{tls}) == Net::SSLeay::ST_OK () + and (delete $self->{_on_starttls})->($self, 1, "TLS/SSL connection established"); } =item $handle->starttls ($tls[, $tls_ctx]) @@ -1448,6 +1859,10 @@ object is created, you can also do that at a later time by calling C. +Starting TLS is currently an asynchronous operation - when you push some +write data and then call C<< ->starttls >> then TLS negotiation will start +immediately, after which the queued write data is then sent. + The first argument is the same as the C constructor argument (either C<"connect">, C<"accept"> or an existing Net::SSLeay object). @@ -1461,32 +1876,41 @@ changed to your liking. Note that the handshake might have already started when this function returns. -If it an error to start a TLS handshake more than once per -AnyEvent::Handle object (this is due to bugs in OpenSSL). +Due to bugs in OpenSSL, it might or might not be possible to do multiple +handshakes on the same stream. It is best to not attempt to use the +stream after stopping TLS. + +This method may invoke callbacks (and therefore the handle might be +destroyed after it returns). =cut our %TLS_CACHE; #TODO not yet documented, should we? sub starttls { - my ($self, $ssl, $ctx) = @_; + my ($self, $tls, $ctx) = @_; + + Carp::croak "It is an error to call starttls on an AnyEvent::Handle object while TLS is already active, caught" + if $self->{tls}; + + $self->{tls} = $tls; + $self->{tls_ctx} = $ctx if @_ > 2; + + return unless $self->{fh}; require Net::SSLeay; - Carp::croak "it is an error to call starttls more than once on an AnyEvent::Handle object" - if $self->{tls}; + $ERROR_SYSCALL = Net::SSLeay::ERROR_SYSCALL (); + $ERROR_WANT_READ = Net::SSLeay::ERROR_WANT_READ (); - $ERROR_SYSCALL = Net::SSLeay::ERROR_SYSCALL (); - $ERROR_WANT_READ = Net::SSLeay::ERROR_WANT_READ (); - $ERROR_ZERO_RETURN = Net::SSLeay::ERROR_ZERO_RETURN (); + $tls = delete $self->{tls}; + $ctx = $self->{tls_ctx}; - $ctx ||= $self->{tls_ctx}; + local $Carp::CarpLevel = 1; # skip ourselves when creating a new context or session if ("HASH" eq ref $ctx) { require AnyEvent::TLS; - local $Carp::CarpLevel = 1; # skip ourselves when creating a new context - if ($ctx->{cache}) { my $key = $ctx+0; $ctx = $TLS_CACHE{$key} ||= new AnyEvent::TLS %$ctx; @@ -1496,7 +1920,7 @@ } $self->{tls_ctx} = $ctx || TLS_CTX (); - $self->{tls} = $ssl = $self->{tls_ctx}->_get_session ($ssl, $self, $self->{peername}); + $self->{tls} = $tls = $self->{tls_ctx}->_get_session ($tls, $self, $self->{peername}); # basically, this is deep magic (because SSL_read should have the same issues) # but the openssl maintainers basically said: "trust us, it just works". @@ -1513,12 +1937,17 @@ # Net::SSLeay::CTX_set_mode ($ssl, # (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ENABLE_PARTIAL_WRITE () } || 1) # | (eval { local $SIG{__DIE__}; Net::SSLeay::MODE_ACCEPT_MOVING_WRITE_BUFFER () } || 2)); - Net::SSLeay::CTX_set_mode ($ssl, 1|2); + Net::SSLeay::CTX_set_mode ($tls, 1|2); $self->{_rbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); $self->{_wbio} = Net::SSLeay::BIO_new (Net::SSLeay::BIO_s_mem ()); - Net::SSLeay::set_bio ($ssl, $self->{_rbio}, $self->{_wbio}); + Net::SSLeay::BIO_write ($self->{_rbio}, delete $self->{rbuf}); + + Net::SSLeay::set_bio ($tls, $self->{_rbio}, $self->{_wbio}); + + $self->{_on_starttls} = sub { $_[0]{on_starttls}(@_) } + if $self->{on_starttls}; &_dotls; # need to trigger the initial handshake $self->start_read; # make sure we actually do read @@ -1528,22 +1957,25 @@ Shuts down the SSL connection - this makes a proper EOF handshake by sending a close notify to the other side, but since OpenSSL doesn't -support non-blocking shut downs, it is not possible to re-use the stream -afterwards. +support non-blocking shut downs, it is not guaranteed that you can re-use +the stream afterwards. + +This method may invoke callbacks (and therefore the handle might be +destroyed after it returns). =cut sub stoptls { my ($self) = @_; - if ($self->{tls}) { + if ($self->{tls} && $self->{fh}) { Net::SSLeay::shutdown ($self->{tls}); &_dotls; - # we don't give a shit. no, we do, but we can't. no... - # we, we... have to use openssl :/ - &_freetls; +# # we don't give a shit. no, we do, but we can't. no...#d# +# # we, we... have to use openssl :/#d# +# &_freetls;#d# } } @@ -1552,9 +1984,10 @@ return unless $self->{tls}; - $self->{tls_ctx}->_put_session (delete $self->{tls}); + $self->{tls_ctx}->_put_session (delete $self->{tls}) + if $self->{tls} > 0; - delete @$self{qw(_rbio _wbio _tls_wbuf)}; + delete @$self{qw(_rbio _wbio _tls_wbuf _on_starttls)}; } sub DESTROY { @@ -1564,13 +1997,13 @@ my $linger = exists $self->{linger} ? $self->{linger} : 3600; - if ($linger && length $self->{wbuf}) { + if ($linger && length $self->{wbuf} && $self->{fh}) { my $fh = delete $self->{fh}; my $wbuf = delete $self->{wbuf}; my @linger; - push @linger, AnyEvent->io (fh => $fh, poll => "w", cb => sub { + push @linger, AE::io $fh, 1, sub { my $len = syswrite $fh, $wbuf, length $wbuf; if ($len > 0) { @@ -1578,18 +2011,20 @@ } else { @linger = (); # end } - }); - push @linger, AnyEvent->timer (after => $linger, cb => sub { + }; + push @linger, AE::timer $linger, 0, sub { @linger = (); - }); + }; } } =item $handle->destroy Shuts down the handle object as much as possible - this call ensures that -no further callbacks will be invoked and resources will be freed as much -as possible. You must not call any methods on the object afterwards. +no further callbacks will be invoked and as many resources as possible +will be freed. Any method you will call on the handle object after +destroying it in this way will be silently ignored (and it will return the +empty list). Normally, you can just "forget" any references to an AnyEvent::Handle object and it will simply shut down. This works in fatal error and EOF @@ -1598,6 +2033,11 @@ within such an callback. You I call C<< ->destroy >> explicitly in that case. +Destroying the handle object in this way has the advantage that callbacks +will be removed as well, so if those are the only reference holders (as +is common), then one doesn't need to do anything special to break any +reference cycles. + The handle might still linger in the background and write out remaining data, as specified by the C option, however. @@ -1608,8 +2048,36 @@ $self->DESTROY; %$self = (); + bless $self, "AnyEvent::Handle::destroyed"; +} + +sub AnyEvent::Handle::destroyed::AUTOLOAD { + #nop } +=item $handle->destroyed + +Returns false as long as the handle hasn't been destroyed by a call to C<< +->destroy >>, true otherwise. + +Can be useful to decide whether the handle is still valid after some +callback possibly destroyed the handle. For example, C<< ->push_write >>, +C<< ->starttls >> and other methods can call user callbacks, which in turn +can destroy the handle, so work can be avoided by checking sometimes: + + $hdl->starttls ("accept"); + return if $hdl->destroyed; + $hdl->push_write (... + +Note that the call to C will silently be ignored if the handle +has been destroyed, so often you can just ignore the possibility of the +handle being destroyed. + +=cut + +sub destroyed { 0 } +sub AnyEvent::Handle::destroyed::destroyed { 1 } + =item AnyEvent::Handle::TLS_CTX This function creates and returns the AnyEvent::TLS object used by default @@ -1650,11 +2118,11 @@ reading? Unlike, say, TCP, TLS connections do not consist of two independent -communication channels, one for each direction. Or put differently. The +communication channels, one for each direction. Or put differently, the read and write directions are not independent of each other: you cannot write data unless you are also prepared to read, and vice versa. -This can mean than, in TLS mode, you might get C or C +This means that, in TLS mode, you might get C or C callback invocations when you are not expecting any read data - the reason is that AnyEvent::Handle always reads in TLS mode. @@ -1674,12 +2142,11 @@ $handle->on_eof (undef); $handle->on_error (sub { my $data = delete $_[0]{rbuf}; - undef $handle; }); The reason to use C is that TCP connections, due to latencies and packets loss, might get closed quite violently with an error, when in -fact, all data has been received. +fact all data has been received. It is usually better to use acknowledgements when transferring data, to make sure the other side hasn't just died and you got the data @@ -1700,6 +2167,94 @@ undef $handle; }); +If you just want to queue some data and then signal EOF to the other side, +consider using C<< ->push_shutdown >> instead. + +=item I want to contact a TLS/SSL server, I don't care about security. + +If your TLS server is a pure TLS server (e.g. HTTPS) that only speaks TLS, +connect to it and then create the AnyEvent::Handle with the C +parameter: + + tcp_connect $host, $port, sub { + my ($fh) = @_; + + my $handle = new AnyEvent::Handle + fh => $fh, + tls => "connect", + on_error => sub { ... }; + + $handle->push_write (...); + }; + +=item I want to contact a TLS/SSL server, I do care about security. + +Then you should additionally enable certificate verification, including +peername verification, if the protocol you use supports it (see +L, C). + +E.g. for HTTPS: + + tcp_connect $host, $port, sub { + my ($fh) = @_; + + my $handle = new AnyEvent::Handle + fh => $fh, + peername => $host, + tls => "connect", + tls_ctx => { verify => 1, verify_peername => "https" }, + ... + +Note that you must specify the hostname you connected to (or whatever +"peername" the protocol needs) as the C argument, otherwise no +peername verification will be done. + +The above will use the system-dependent default set of trusted CA +certificates. If you want to check against a specific CA, add the +C (or C) arguments to C: + + tls_ctx => { + verify => 1, + verify_peername => "https", + ca_file => "my-ca-cert.pem", + }, + +=item I want to create a TLS/SSL server, how do I do that? + +Well, you first need to get a server certificate and key. You have +three options: a) ask a CA (buy one, use cacert.org etc.) b) create a +self-signed certificate (cheap. check the search engine of your choice, +there are many tutorials on the net) or c) make your own CA (tinyca2 is a +nice program for that purpose). + +Then create a file with your private key (in PEM format, see +L), followed by the certificate (also in PEM format). The +file should then look like this: + + -----BEGIN RSA PRIVATE KEY----- + ...header data + ... lots of base64'y-stuff + -----END RSA PRIVATE KEY----- + + -----BEGIN CERTIFICATE----- + ... lots of base64'y-stuff + -----END CERTIFICATE----- + +The important bits are the "PRIVATE KEY" and "CERTIFICATE" parts. Then +specify this file as C: + + tcp_server undef, $port, sub { + my ($fh) = @_; + + my $handle = new AnyEvent::Handle + fh => $fh, + tls => "accept", + tls_ctx => { cert_file => "my-server-keycert.pem" }, + ... + +When you have intermediate CA certificates that your clients might not +know about, just append them to the C. + =back @@ -1728,7 +2283,7 @@ are free to use in subclasses. Of course, new versions of AnyEvent::Handle may introduce more "public" -member variables, but thats just life, at least it is documented. +member variables, but that's just life. At least it is documented. =back