Remove the "whence" parameter that is not actually necessary, and only
complicates the InputStream implementations.

Prepare to migrate away from GLib.  Currently, we're still using GLib
as a backend.

Replaces GLib's GError.

Hide the definition from C code, to prepare the transition to C++.

This might break older versions, I didn't test.

This might break older versions, I didn't test.

Pass a callback table to scan_file() and scan_stream(), instead of
returning a tag object.

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

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.

Remove trailing whitespace found by this command:
find -name '*.[ch]' | xargs grep "[[:space:]]$"

Make it X_decoder_plugin.c.

This function replaces the replay_gain_info parameter for
decoder_data().  This allows the decoder to announce replay gain
changes, instead of having to pass the same object over and over.

Remove the data_time parameter from decoder_data().  This patch
eliminates the timestamp counting in most decoder plugins, because the
MPD core will do it automatically by default.

This patch prepares support for floating point samples (and probably
other formats).  It changes the meaning of the "bits" attribute from a
bit count to a symbolic value.

Pass the audiofile_setup_sample_format() result to
audio_format_init_checked().