Re: [PATCH v2 1/2] submodule: port submodule subcommand 'sync' from shell to C

Prathamesh Chavan [off-list ref] writes:

+		} else {
+			sub_origin_url = xstrdup(sub->url);
+			super_config_url = xstrdup(sub->url);
+		}
+	} else {
+		sub_origin_url = "";
+		super_config_url = "";
+	}
+ ...
+cleanup:
+	if (strlen(super_config_url))
+		free(super_config_url);
+	if (strlen(sub_origin_url))
+		free(sub_origin_url);

The above is ugly and veriy likely to be wrong; imagine that
sub->url was an empty string to begin with.

Doing xstrdup("") before assigning the constant to *_url would be a
lot more sensible and maintainable solution for things like this.