prototype: pEp::String - avoid nullptr in the char* (if the c_str_p is nullptr then init with "")

test/test_nr1.cc

@@ -204,6 +204,11 @@ namespace pEp {
             _is_bound = true;
             pEpLogClass(to_string());
             set_owner(is_owner);
+
+            //if the c_str_p is nullptr then init with ""
+            if (*_c_str_pp == nullptr) {
+                this->operator=("");
+            }
         }
 
         ~String()
@@ -225,14 +230,7 @@ namespace pEp {
             _free();
 
             // ALLOCATION
-            if (str.empty()) {
+            *_c_str_pp = _copy(str);
-                // if the new value is empty str, lets point to nothing
-                *_c_str_pp = nullptr;
-                _c_str_p = *_c_str_pp;
-            } else {
-                *_c_str_pp = pEp::alloc_str(str);
-                _c_str_p = *_c_str_pp;
-            }
             pEpLogClass("After:  " + to_string());
             return *this;
         }