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