restructure control commands

code/common/src/utils.c

@@ -632,4 +632,14 @@ replace_substring(const char* source,
     }
     *result_pos = '\0';
     return result;
+}
+
+char *
+string_or_na(char *string)
+{
+    if(string) {
+        return string;
+    } else {
+        return "N/A";
+    }
 }

code/common/src/utils.h

@@ -45,5 +45,6 @@ bool  ipv6_addr_not_zero(ipv6addr_t *addr);
 bool  ipv6_prefix_not_zero(ipv6_prefix *prefix);
 
 char *replace_substring(const char* s, const char* old, const char* new);
+char *string_or_na(char *string);
 
 #endif