build: Do not overwrite lv_conf.defaults in source path

When a non-default lv_conf.defaults is used it is currenly copied out of
the configs/ directory replacing the existing lv_conf.defaults file. This
makes changes to source files during build which should be avoided, only
modifications should happen in the build directory.

There is no need to do this as we can simply update the path used to
locate lv_conf.defaults in CMake to the non-default file path and use
it just the same.

Signed-off-by: Andrew Davis <afd@ti.com>

Author: glneo

CMakeLists.txt

@@ -25,35 +25,16 @@ set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Wall -Wextra -Wpedantic")
 set(CONFIG "default" CACHE STRING "Config name to use. Leave empty for default `lv_conf.defaults`")
 
 set(LV_CONF_DEFAULTS_PATH "${CMAKE_SOURCE_DIR}/lv_conf.defaults")
-set(LV_CONF_DEFAULTS_OLD_PATH "${CMAKE_SOURCE_DIR}/lv_conf.defaults.old")
 
-# If CONFIG is not default, copy the selected config to lv_conf.defaults
+# If CONFIG is not default, update LV_CONF_DEFAULTS_PATH to the selected config
 if(NOT CONFIG STREQUAL "default")
-    set(CONFIG_FILE "${CMAKE_SOURCE_DIR}/configs/${CONFIG}.defaults")
-    
-    # Verify the config file exists
-    if(NOT EXISTS "${CONFIG_FILE}")
-        message(FATAL_ERROR "Config file not found: ${CONFIG_FILE}")
-    endif()
-    
-    # Backup the current lv_conf.defaults to lv_conf.defaults.old
-    if(EXISTS "${LV_CONF_DEFAULTS_PATH}")
-        file(RENAME "${LV_CONF_DEFAULTS_PATH}" "${LV_CONF_DEFAULTS_OLD_PATH}")
-        message(STATUS "Backed up lv_conf.defaults to lv_conf.defaults.old")
-    endif()
-    
-    # Copy the config file to lv_conf.defaults
-    configure_file("${CONFIG_FILE}" "${LV_CONF_DEFAULTS_PATH}" COPYONLY)
-    message(STATUS "Copied configs/${CONFIG}.defaults to ${LV_CONF_DEFAULTS_PATH}")
-    message(STATUS "Using config: configs/${CONFIG}.defaults")
-else()
-    if(NOT EXISTS "${LV_CONF_DEFAULTS_PATH}")
-        message(FATAL_ERROR "Config file not found: ${LV_CONF_DEFAULTS_PATH}")
-    endif()
-    message(STATUS "Using default lv_conf.defaults")
-    message(STATUS "Using config: ${LV_CONF_DEFAULTS_PATH}")
+    set(LV_CONF_DEFAULTS_PATH "${CMAKE_SOURCE_DIR}/configs/${CONFIG}.defaults")
 endif()
 
+if(NOT EXISTS "${LV_CONF_DEFAULTS_PATH}")
+    message(FATAL_ERROR "Config file not found: ${LV_CONF_DEFAULTS_PATH}")
+endif()
+message(STATUS "Using config: ${LV_CONF_DEFAULTS_PATH}")
 
 set(LV_BUILD_SET_CONFIG_OPTS ON CACHE BOOL
     "create CMAKE variables from lv_conf_internal.h" FORCE)