add_subdirectory(common)

if (CMAKE_SYSTEM_NAME MATCHES "Darwin")
  add_subdirectory(macosx)
elseif (CMAKE_SYSTEM_NAME MATCHES "Linux")
  add_subdirectory(linux)
elseif (CMAKE_SYSTEM_NAME MATCHES "FreeBSD")
  add_subdirectory(freebsd)
elseif (CMAKE_SYSTEM_NAME MATCHES "Windows")
  add_subdirectory(windows)
endif()