Some cleanup work

include/cmd.h

@@ -56,7 +56,10 @@ struct arg_values{
 
 	int fade_steps;
 
-	unsigned char operation;
+	union{
+		int operation;
+		int num_values;
+	};
 };
 
 

include/common.h

@@ -19,6 +19,12 @@
 #ifndef REXBACKLIGHT_COMMON_H
 #define REXBACKLIGHT_COMMON_H
 
+#ifdef REXBACKLIGHT_DEBUG
+#define DEBUG_PRINT(s, ...) printf(s, __VA_ARGS__)
+#else
+#define DEBUG_PRINT(s, ...)
+#endif
+
 #define RETVAL_INVALID_FILE         1
 #define RETVAL_INVALID_DIR          2
 #define RETVAL_UNRECOGNIZED_OPTION  3
@@ -45,6 +51,7 @@ struct string_array{
 	char** list;
 	int size;
 };
+void free_string_array(struct string_array* s);
 
 void mem_error(void);
 _Noreturn void version(void);