check IS_DIRECTORY LIB_INSTALL_DIR

CMakeLists.txt

@@ -4,8 +4,22 @@ project(stlink C)
 set(PROJECT_DESCRIPTION "Open source version of the STMicroelectronics Stlink Tools")
 set(STLINK_UDEV_RULES_DIR "/etc/udev/rules.d" CACHE PATH "Udev rules directory")
 set(STLINK_MODPROBED_DIR "/etc/modprobe.d" CACHE PATH "modprobe.d directory")
-set(LIB_INSTALL_DIR "lib" CACHE PATH "Main library directory")
-set(STLINK_LIBRARY_PATH "${CMAKE_INSTALL_PREFIX}/${LIB_INSTALL_DIR}" CACHE PATH "Target lib directory")
+
+if( IS_DIRECTORY LIB_INSTALL_DIR)
+    set(LIB_INSTALL_DIR ${LIB_INSTALL_DIR} CACHE PATH "Main library directory")
+    set(STLINK_LIBRARY_PATH "${LIB_INSTALL_DIR}" CACHE PATH "Target lib directory")
+else()
+    set(LIB_INSTALL_DIR "lib" CACHE PATH "Main library directory")
+    set(STLINK_LIBRARY_PATH "${CMAKE_INSTALL_PREFIX}/${LIB_INSTALL_DIR}" CACHE PATH "Target lib directory")
+endif()
+
+if( IS_DIRECTORY INCLUDE_INSTALL_DIR)
+    set(INCLUDE_INSTALL_DIR ${INCLUDE_INSTALL_DIR} CACHE PATH "Main include directory")
+    set(STLINK_INCLUDE_PATH "${INCLUDE_INSTALL_DIR}" CACHE PATH "Target include directory")
+else()
+    set(INCLUDE_INSTALL_DIR "include" CACHE PATH "Main include directory")
+    set(STLINK_INCLUDE_PATH "${CMAKE_INSTALL_PREFIX}/${INCLUDE_INSTALL_DIR}" CACHE PATH "Target include directory")
+endif()
 
 option(STLINK_GENERATE_MANPAGES "Generate manpages with pandoc" OFF)
 

include/CMakeLists.txt

@@ -7,8 +7,8 @@ file(GLOB STLINK_HEADERS
 	"${CMAKE_BINARY_DIR}/include/stlink/*.h"
 )
 install(FILES ${CMAKE_SOURCE_DIR}/include/stlink.h
-    DESTINATION ${CMAKE_INSTALL_PREFIX}/include
+    DESTINATION ${STLINK_INCLUDE_PATH}
 )
 install(FILES ${STLINK_HEADERS}
-    DESTINATION include/${CMAKE_INSTALL_PREFIX}/include/stlink
+    DESTINATION ${STLINK_INCLUDE_PATH}/stlink
 )