This is a rather huge patch, which unfortunately cannot be splitted.

Instead of using our custom ioops.h library, convert everything to use
the GLib main loop.

Moved implementation specific code to their own sources, internal
declarations in zeroconf-internal.h.

If the configured avahi service name is invalid, abort MPD.  Don't
fall back to the default service name.

Only include headers which are really needed.  os_compat.h aimed to
make MPD easily portable, but was never actually made portable.

If a feature is disabled, don't compile the source file at all,
disable it completely in Makefile.am instead.

Also enable -Wunused-parameter - this forces us to add the gcc
"unused" attribute to a lot of parameters (mostly library callback
functions), but it's worth it during code refactorizations.

Also, lower the impact of compiling this w/o zeroconf by
making the init/teardown functions static no-ops.

Eventually, we should separate the Bonjour and Avahi
code into separate files and have callbacks registered
for each one, avoiding the #ifdef mess we have now...

git-svn-id: https://svn.musicpd.org/mpd/trunk@7132 09075e82-0dd4-0310-85a5-a0d7c8717e4f

This will make refactoring features easier, especially now that
pthreads support and larger refactorings are on the horizon.

Hopefully, this will make porting to other platforms (even
non-UNIX-like ones for masochists) easier, too.

os_compat.h will house all the #includes for system headers
considered to be the "core" of MPD.  Headers for optional
features will be left to individual source files.

git-svn-id: https://svn.musicpd.org/mpd/trunk@7130 09075e82-0dd4-0310-85a5-a0d7c8717e4f

the force flag will issue FATAL() if an invalid value is
specified

git-svn-id: https://svn.musicpd.org/mpd/trunk@6857 09075e82-0dd4-0310-85a5-a0d7c8717e4f

This should fix Debian bug #428551
(mpd crashes when restarting the dbus daemon)

git-svn-id: https://svn.musicpd.org/mpd/trunk@6844 09075e82-0dd4-0310-85a5-a0d7c8717e4f

silence a warning about an unused variable without using stupid checks for
HAVE_AVAHI || HAVE_BONJOUR.

git-svn-id: https://svn.musicpd.org/mpd/trunk@6471 09075e82-0dd4-0310-85a5-a0d7c8717e4f

git-svn-id: https://svn.musicpd.org/mpd/trunk@6470 09075e82-0dd4-0310-85a5-a0d7c8717e4f

git-svn-id: https://svn.musicpd.org/mpd/trunk@6468 09075e82-0dd4-0310-85a5-a0d7c8717e4f

git-svn-id: https://svn.musicpd.org/mpd/trunk@6467 09075e82-0dd4-0310-85a5-a0d7c8717e4f

git-svn-id: https://svn.musicpd.org/mpd/trunk@6462 09075e82-0dd4-0310-85a5-a0d7c8717e4f

I couldn't test mDNSResponder support on Linux, as Debian doesn't include it - but should work as well.

git-svn-id: https://svn.musicpd.org/mpd/trunk@6453 09075e82-0dd4-0310-85a5-a0d7c8717e4f

git-svn-id: https://svn.musicpd.org/mpd/trunk@6445 09075e82-0dd4-0310-85a5-a0d7c8717e4f

git-svn-id: https://svn.musicpd.org/mpd/trunk@6112 09075e82-0dd4-0310-85a5-a0d7c8717e4f

git-svn-id: https://svn.musicpd.org/mpd/trunk@5834 09075e82-0dd4-0310-85a5-a0d7c8717e4f

git-svn-id: https://svn.musicpd.org/mpd/trunk@5262 09075e82-0dd4-0310-85a5-a0d7c8717e4f

git-svn-id: https://svn.musicpd.org/mpd/trunk@5259 09075e82-0dd4-0310-85a5-a0d7c8717e4f

Some compilers and linkers aren't smart enough to optimize this,
as global variables are implictly initialized to zero.  As a
result, binaries are a bit smaller as more goes in the .bss and
less in the text section.

git-svn-id: https://svn.musicpd.org/mpd/trunk@5254 09075e82-0dd4-0310-85a5-a0d7c8717e4f

git-svn-id: https://svn.musicpd.org/mpd/trunk@5243 09075e82-0dd4-0310-85a5-a0d7c8717e4f

git-svn-id: https://svn.musicpd.org/mpd/trunk@5238 09075e82-0dd4-0310-85a5-a0d7c8717e4f