If a connected host disappears without our knowledge, as can happen over
wireless or a hibernating machine, we continue to hold the port open waiting
for messages. Because we never try to send anything down this now-broken
pipe, the connection will sit idle taking up a slot in our allowed incoming
connections list.

If enough of these happen, an unintended Denial of Service takes place,
where all connection slots are filled with now-broken, never ending
connections. Setting the TCP keepalive option at least allows these to time
out after the default two hours, which is sufficient in the non-malicious
case.
Signed-off-by: Dan McGee <dan@archlinux.org>

Pass audio_output objects around instead of void pointers.  This will
give some more control to the plugin, and prepares for non-blocking
audio outputs.

Work around automake warning.

Fixes gcc warnings.

Wrap the locking code.

GLib has a built-in OOM handler.

Consistent naming.

Move the "extern" declarations from output_list.c, for more type
safety.

Provide _lock() and _unlock() to wrap all accesses from the mixer
plugin.

Use these instead of exposing the internal roar_t struct.

The stdio header is no longer pulled in by af_vfs.h in audiofile-0.3.0.

Always lock the main loop when operating on PULSE objects.  Document
this.

Copy the reason_phrase from the SoupMessage, and check for transport
errors in the session callback.

Add GMutex, GCond attributes which will be used by callers to
conditionally wait on the stream.

Remove the (now-useless) plugin method buffer(), wait on GCond
instead.  Lock the input_stream before each method call.  Do the same
with the playlist plugins.

To check for errors without reading.  The decoder thread wants to do
that, before it passes the input stream to the plugin.

Fix memory leak.

libsoup's asynchronous API is not thread safe.  By moving the calls
into the I/O thread, several crash bugs will be fixed.

Add the "complete" attribute, and set it in _session_callback().
_close() waits for it to become true.

Add attribute postponed_error, pass this GError to the caller.

Fix deadlock.

We'll add proper locking now, and there's no need to carry this
duplicate flag.

To report failures to callers who don't use _buffer().

Avoid recursive deadlock in _session_callback().

This was useless, because input_stream_read() blocks until data is
available.  Calling it in a loop doesn't make sense.

Pausing and resuming after every little chunk adds lots of overhead.
Add a lower level for resuming the stream.

curl_easy_pause(CURLPAUSE_CONT) may have added enough data to go into
pause again.

Call _update_fds() directly.  This is possible because it's only
called from within the I/O thread.

Fix deadlock.