Wrap subdirectory compilation in conditional

CMakeLists.txt

@@ -3,6 +3,8 @@ project(akgl LANGUAGES C)
 
 include(CTest)
 
+if(CMAKE_SOURCE_DIR STREQUAL CMAKE_CURRENT_SOURCE_DIR)
+  
 add_subdirectory(deps/jansson EXCLUDE_FROM_ALL)
 add_subdirectory(deps/libakerror EXCLUDE_FROM_ALL)
 add_subdirectory(deps/libakstdlib EXCLUDE_FROM_ALL)
@@ -11,6 +13,10 @@ add_subdirectory(deps/SDL_image EXCLUDE_FROM_ALL)
 add_subdirectory(deps/SDL_mixer EXCLUDE_FROM_ALL)
 add_subdirectory(deps/SDL_ttf EXCLUDE_FROM_ALL)
 
+else()
+
+endif()
+
 set(GAMECONTROLLERDB_H "include/akgl/SDL_GameControllerDB.h")
 set(prefix      ${CMAKE_INSTALL_PREFIX})
 set(exec_prefix "\${prefix}")