Convert fs_host files from c back to cpp and style changes.

* fs_darwin.c => fs_darwin.cpp
* fs_freebsd.c => fs_freebsd.cpp
* use bool instead of int again in fs_darwin.cpp (C => C++)
* declare loop varibles inline again in fs_freebsd.cpp (C => C++)
* 2 newlines between top header gaurd and first #include
* 2 newlines after last #include
* freebsd/endian.h and freebsd/regex.h convert \r\n to just \n
* remove some leading tabs in fs_freebsd.cpp
* add newlines after single line if statement in fs_freebsd.cpp
* 80-char limit fixes in fs_freebsd.cpp

Cleanup darwin build system some more.

* Convert fs_darwin.cpp and fs_freebsd.cpp to C.
* Convert extern C calls to __BEGIN_DECLS and __END_DECLS macros
* Link rm_attrs with dynamic libroot

Split fs_darwin.h defines into various platform dependent headers.

This completes the final 1/3 of #8857. Changes again by nielx with
style fixes by me.

The one part that I couldn't figure out, and maybe Ingo can chime
in here. If headers/build/host/darwin/sys/stat.h is surrounded in

extern "C" {

}

guards then I get a link error complaining that the functions defined
here are duplicate symbols, once in fs.o and once in function_remapper.o.
For example:

ld: duplicate symbol _futimens in generated/objects/darwin/x86_64/release/build/libroot/libroot_build_function_remapper.a(function_remapper.o) and generated/objects/darwin/x86_64/release/build/libroot/libroot_build.a(fs.o) for architecture x86_64

I'm not sure why that is.

Add fopendir() to fs_darwin.cpp and fix symlinkat().

This completes 2/3 of #8857 and is courtesy of nielx.

Style fixes suggested by Axeld.
Added Ingo to the copyright
Updated copyright year to 2012 for my contribution.

Fix build on Mac OS X 10.6 gcc2 and gcc4 and 10.7 gcc4 by adding some Mac OS X specific files that implement missing *at() functions.
Mac OS X 10.7 generates a gcc2 cross-compiler that fails when assigning NULL to a static method pointer so is still broken.
Added a weak attribute in driver_settings.cpp.
Move futimesat() from fs.cpp to fs_darwin.cpp since it is implimented on FreeBSD.
Implemented eaccess(), for the AT_EACCESS flag of faccessat()
Fix configure script to correctly detect case-sensitive file system

Move futimesat() from fs.cpp to fs_darwin.cpp since it is implimented on FreeBSD. It is stubbed out for now.

Fix build by adding some Mac OS X specific files that implement fs function missing on that OS. The functions are stubbed out currently and have not been implemented. However, it does build now. I also added a weak attribute in driver_settings.cpp that I have no idea what does but was necessary to fix the build.

Convert fs_host files from c back to cpp and style changes.

* fs_darwin.c => fs_darwin.cpp
* fs_freebsd.c => fs_freebsd.cpp
* use bool instead of int again in fs_darwin.cpp (C => C++)
* declare loop varibles inline again in fs_freebsd.cpp (C => C++)
* 2 newlines between top header gaurd and first #include
* 2 newlines after last #include
* freebsd/endian.h and freebsd/regex.h convert \r\n to just \n
* remove some leading tabs in fs_freebsd.cpp
* add newlines after single line if statement in fs_freebsd.cpp
* 80-char limit fixes in fs_freebsd.cpp

Cleanup darwin build system some more.

* Convert fs_darwin.cpp and fs_freebsd.cpp to C.
* Convert extern C calls to __BEGIN_DECLS and __END_DECLS macros
* Link rm_attrs with dynamic libroot

Split fs_darwin.h defines into various platform dependent headers.

This completes the final 1/3 of #8857. Changes again by nielx with
style fixes by me.

The one part that I couldn't figure out, and maybe Ingo can chime
in here. If headers/build/host/darwin/sys/stat.h is surrounded in

extern "C" {

}

guards then I get a link error complaining that the functions defined
here are duplicate symbols, once in fs.o and once in function_remapper.o.
For example:

ld: duplicate symbol _futimens in generated/objects/darwin/x86_64/release/build/libroot/libroot_build_function_remapper.a(function_remapper.o) and generated/objects/darwin/x86_64/release/build/libroot/libroot_build.a(fs.o) for architecture x86_64

I'm not sure why that is.

Add fopendir() to fs_darwin.cpp and fix symlinkat().

This completes 2/3 of #8857 and is courtesy of nielx.

Style fixes suggested by Axeld.
Added Ingo to the copyright
Updated copyright year to 2012 for my contribution.

Fix build on Mac OS X 10.6 gcc2 and gcc4 and 10.7 gcc4 by adding some Mac OS X specific files that implement missing *at() functions.
Mac OS X 10.7 generates a gcc2 cross-compiler that fails when assigning NULL to a static method pointer so is still broken.
Added a weak attribute in driver_settings.cpp.
Move futimesat() from fs.cpp to fs_darwin.cpp since it is implimented on FreeBSD.
Implemented eaccess(), for the AT_EACCESS flag of faccessat()
Fix configure script to correctly detect case-sensitive file system

Move futimesat() from fs.cpp to fs_darwin.cpp since it is implimented on FreeBSD. It is stubbed out for now.

Fix build by adding some Mac OS X specific files that implement fs function missing on that OS. The functions are stubbed out currently and have not been implemented. However, it does build now. I also added a weak attribute in driver_settings.cpp that I have no idea what does but was necessary to fix the build.