fix cmakelist.txt

Author: prudhomm

CMakeLists.txt

@@ -38,16 +38,30 @@ endif ()
 
 include(GNUInstallDirs)
 
-set(FMI4CPP_HEADER_INSTALL_DIR "${CMAKE_INSTALL_INCLUDEDIR}")
-set(FMI4CPP_CMAKE_INSTALL_DIR "${CMAKE_INSTALL_DATADIR}/${PROJECT_NAME}")
-set(FMI4CPP_DOC_INSTALL_DIR "${CMAKE_INSTALL_DOCDIR}")
+if (NOT DEFINED FMI4CPP_HEADER_INSTALL_DIR)
+    set(FMI4CPP_HEADER_INSTALL_DIR "${CMAKE_INSTALL_INCLUDEDIR}")
+endif ()
+if (NOT DEFINED FMI4CPP_INSTALL_BIN_DIR)
+    set(FMI4CPP_INSTALL_BIN_DIR "${CMAKE_INSTALL_BINDIR}")
+endif ()
+if (NOT DEFINED FMI4CPP_INSTALL_LIB_DIR)
+    set(FMI4CPP_INSTALL_LIB_DIR "${CMAKE_INSTALL_LIBDIR}")
+endif ()
+if (NOT DEFINED FMI4CPP_CMAKE_INSTALL_DIR)
+    set(FMI4CPP_CMAKE_INSTALL_DIR "${CMAKE_INSTALL_DATADIR}/${PROJECT_NAME}")
+endif ()
+if (NOT DEFINED FMI4CPP_DOC_INSTALL_DIR)
+    set(FMI4CPP_DOC_INSTALL_DIR "${CMAKE_INSTALL_DOCDIR}")
+endif ()
 
 set(FMI4CPP_INSTALL_DESTINATIONS
-        ARCHIVE DESTINATION "lib"
-        LIBRARY DESTINATION "lib"
-        RUNTIME DESTINATION "bin"
+        ARCHIVE DESTINATION "${FMI4CPP_INSTALL_LIB_DIR}"
+        LIBRARY DESTINATION "${FMI4CPP_INSTALL_LIB_DIR}"
+        RUNTIME DESTINATION "${FMI4CPP_INSTALL_BIN_DIR}"
         INCLUDES DESTINATION "${FMI4CPP_HEADER_INSTALL_DIR}")
-set(FMI4CPP_EXPORT_TARGET "${PROJECT_NAME}-targets")
+if (NOT DEFINED FMI4CPP_EXPORT_TARGET)
+    set(FMI4CPP_EXPORT_TARGET "${PROJECT_NAME}-targets")
+endif ()
 
 
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