Provide ares_nameser.h as a public interface

[felixonmars]

Implements #415.

[bradh352]

• move src/lib/ares_nameser.h -> include/ares_nameser.h
• in include/CMakeLists.txt, need to add the ares_nameser.h to the header list
• in configure.ac (or one of the .m4 files) need to set CARES_HAVE_ARPA_NAMESER_H and CARES_HAVE_ARPA_NAMESER_COMPAT_H
• in include/ares_build.h.in need to add the placeholders for CARES_HAVE_ARPA_NAMESER_H and CARES_HAVE_ARPA_NAMESER_COMPAT_H
• Need to include ares_build.h at the top of ares_nameser.h in case it is included without first including ares.h or similar.

[felixonmars]

I have some trouble trying to understand the autotools part here. Do I need to write a dnl from scratch? Seems that I cannot test it too:

$ autoreconf -ifv
<snip>
aclocal: error: too many loops
aclocal: Please contact <bug-automake@gnu.org>.
 at /usr/share/automake-1.16/Automake/Channels.pm line 655.
        Automake::Channels::msg("automake", "", "too many loops") called at /usr/share/automake-1.16/Automake/ChannelDefs.pm line 226
        Automake::ChannelDefs::prog_error("too many loops") called at /usr/bin/aclocal line 1187
autoreconf: error: aclocal failed with exit status: 255

[bradh352]

There is some issue going on with newer automake versions. Can you tell me what automake version you have? We have 2 issues on that #409 and #416. It would be useful if you could tell me what OS and version of the various tools you are running like those 2 tickets (actually, it would be useful to put the output in the ticket #416) to help isolate.

[felixonmars]

It seems to be still broken - the generated ares_build.h still has

/* #undef CARES_HAVE_ARPA_NAMESER_H */
/* #undef CARES_HAVE_ARPA_NAMESER_COMPAT_H */

While the files are present.

[felixonmars]

Okay, I should have done it right this time.