The get_mac_addr() function was the only real blocker that prevented
building on BSD systems, as it used the Linux-specific SIOCGIFHWADDR
ioctl. When compiling for Linux, we still use this ioctl, but for the
BSD version we use sysctl().
This allows OwlPS Listener to build on BSD (tested on NetBSD, OpenBSD
and DragonFly). That doesn't mean it will actually work when trying to
capture packets though (that has to be tested on real hardware), but
that's still a progress.
This patch is to have clang++ (>= 3.2) happily build OwlPS Positioner.
For some reason it doesn't work on NetBSD, but it is fine on GNU/Linux
and (a couple of warnings apart) on DragonFly BSD.
We chose a centralised approach, since threads are needed in several
modules: the find_package() is done only once in the rood directory.
Not sure it's the best approach though, but this test is several lines
long so doing that avoids duplication of this code.
- Default compiler and linker flags were added silently. They are now
set in the cache if no previous values are present.
- Debug flags and regular flags have been merged.
- Position-independent code (doesn't appear in the cache because CMake
lacks variables like CMAKE_EXE_COMPILE_FLAGS):
- Shared libraries are compiled with -fPIC.
- Executables and static libraries are compiled with -fPIE.
- Executables are linked with -pie -fPIE.