[ViewVC] Diff of: cvs/AnyEvent/lib/AnyEvent/Handle.pm

Comparing AnyEvent/lib/AnyEvent/Handle.pm (file contents):
Revision 1.188 by root, Thu Sep 17 08:20:14 2009 UTC vs.
Revision 1.197 by root, Tue Aug 31 00:59:55 2010 UTC

 =head1 NAME
-AnyEvent::Handle - non-blocking I/O on file handles via AnyEvent
+AnyEvent::Handle - non-blocking I/O on streaming handles via AnyEvent
 =head1 SYNOPSIS
    use AnyEvent;
    use AnyEvent::Handle;
    $cv->recv;
 =head1 DESCRIPTION
 This module is a helper module to make it easier to do event-based I/O on
-filehandles.
+stream-based filehandles (sockets, pipes or other stream things).
 The L<AnyEvent::Intro> tutorial contains some well-documented
 AnyEvent::Handle examples.
 In the following, when the documentation refers to of "bytes" then this
 =head1 METHODS
 =over 4
-=item $handle = B<new> AnyEvent::TLS fh => $filehandle, key => value...
+=item $handle = B<new> AnyEvent::Handle fh => $filehandle, key => value...
 The constructor supports these arguments (all as C<< key => value >> pairs).
 =over 4
 To access (and remove data from) the read buffer, use the C<< ->rbuf >>
 method or access the C<< $handle->{rbuf} >> member directly. Note that you
 must not enlarge or modify the read buffer, you can only remove data at
 the beginning from it.
+You can also call C<< ->push_read (...) >> or any other function that
+modifies the read queue. Or do both. Or ...
 When an EOF condition is detected then AnyEvent::Handle will first try to
 feed all the remaining data to the queued callbacks and C<on_read> before
 calling the C<on_eof> callback. If no progress can be made, then a fatal
 error will be raised (with C<$!> set to C<EPIPE>).
 }
 sub _start {
    my ($self) = @_;
+   # 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;
    AnyEvent::Util::fh_nonblocking $self->{fh}, 1;
    $self->{_activity}  =
    $self->{_ractivity} =
    $self->{_wactivity} = AE::now;
 Replace the current C<on_stoptls> callback (see the C<on_stoptls> constructor argument).
 =cut
-sub on_starttls {
+sub on_stoptls {
    $_[0]{on_stoptls} = $_[1];
 }
 =item $handle->rbuf_max ($max_octets)
 =item $handle->on_drain ($cb)
 Sets the C<on_drain> callback or clears it (see the description of
 C<on_drain> in the constructor).
+This method may invoke callbacks (and therefore the handle might be
+destroyed after it returns).
 =cut
 sub on_drain {
    my ($self, $cb) = @_;
 =item $handle->push_write ($data)
 Queues the given scalar to be written. You can push as much data as you
 want (only limited by the available memory), as C<AnyEvent::Handle>
 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 {
    my ($self) = @_;
       @_ = ($WH{$type} ||= _load_func "$type\::anyevent_write_type"
             or Carp::croak "unsupported/unloadable type '$type' passed to AnyEvent::Handle::push_write")
            ->($self, @_);
    }
+   # we downgrade here to avoid hard-to-track-down bugs,
+   # and diagnose the problem earlier and better.
    if ($self->{tls}) {
-      $self->{_tls_wbuf} .= $_[0];
+      utf8::downgrade $self->{_tls_wbuf} .= $_[0];
       &_dotls ($self)    if $self->{fh};
    } else {
-      $self->{wbuf}      .= $_[0];
+      utf8::downgrade $self->{wbuf}      .= $_[0];
       $self->_drain_wbuf if $self->{fh};
    }
 }
 =item $handle->push_write (type => @args)
 Instead of formatting your data yourself, you can also let this module
 do the job by specifying a type and type-specific arguments. You
 can also specify the (fully qualified) name of a package, in which
 case AnyEvent tries to load the package and then expects to find the
-C<anyevent_read_type> function inside (see "custom write types", below).
+C<anyevent_write_type> function inside (see "custom write types", below).
 Predefined types are (if you have ideas for additional types, feel free to
 drop by and tell us):
 =over 4
 the peer.
 You can rely on the normal read queue and C<on_eof> handling
 afterwards. This is the cleanest way to close a connection.
+This method may invoke callbacks (and therefore the handle might be
+destroyed after it returns).
 =cut
 sub push_shutdown {
    my ($self) = @_;
 ways, the "simple" way, using only C<on_read> and the "complex" way, using
 a queue.
 In the simple case, you just install an C<on_read> 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<< $handle->rbuf >>). Or you can
 leave the data there if you want to accumulate more (e.g. when only a
-partial message has been received so far).
+partial message has been received so far), or change the read queue with
+e.g. C<push_read>.
 In the more complex case, you want to queue multiple callbacks. In this
 case, AnyEvent::Handle will call the first queued callback each time new
 data arrives (also the first time it is queued) and removes it when it has
 done its job (see C<push_read>, below).
 This replaces the currently set C<on_read> callback, or clears it (when
 the new callback is C<undef>). See the description of C<on_read> in the
 constructor.
+This method may invoke callbacks (and therefore the handle might be
+destroyed after it returns).
 =cut
 sub on_read {
    my ($self, $cb) = @_;
 available (or an error condition is detected).
 If enough data was available, then the callback must remove all data it is
 interested in (which can be none at all) and return a true value. After returning
 true, it will be removed from the queue.
+These methods may invoke callbacks (and therefore the handle might be
+destroyed after it returns).
 =cut
 our %RH;
 }
 sub start_read {
    my ($self) = @_;
-   unless ($self->{_rw} || $self->{_eof}) {
+   unless ($self->{_rw} || $self->{_eof} || !$self->{fh}) {
       Scalar::Util::weaken $self;
       $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;
          && ($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");
 when this function returns.
 Due to bugs in OpenSSL, it might or might not be possible to do multiple
 handshakes on the same stream. Best do 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?
 =item $handle->stoptls
 Shuts down the SSL connection - this makes a proper EOF handshake by
 sending a close notify to the other side, but since OpenSSL doesn't
-support non-blocking shut downs, it is not guarenteed that you can re-use
+support non-blocking shut downs, it is not guaranteed that you can re-use
 the stream afterwards.
+This method may invoke callbacks (and therefore the handle might be
+destroyed after it returns).
 =cut
 sub stoptls {
    my ($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...#d#
 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<push_write> 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
 for TLS mode.

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Comparing AnyEvent/lib/AnyEvent/Handle.pm (file contents): Revision 1.188 by root, Thu Sep 17 08:20:14 2009 UTC vs. Revision 1.197 by root, Tue Aug 31 00:59:55 2010 UTC

Diff Legend

Comparing AnyEvent/lib/AnyEvent/Handle.pm (file contents):
Revision 1.188 by root, Thu Sep 17 08:20:14 2009 UTC vs.
Revision 1.197 by root, Tue Aug 31 00:59:55 2010 UTC