librc: use xasprintf in rc_service_description

Author: navi-desu

src/librc/librc.c

@@ -857,17 +857,14 @@ rc_service_description(const char *service, const char *option)
 	char *desc = NULL;
 	size_t size = 0;
 	FILE *fp;
-	size_t l;
 
 	if (!(svc = rc_service_resolve(service)))
 		return NULL;
 
 	if (!option)
 		option = "";
 
-	l = strlen(DESCSTR) + strlen(svc) + strlen(option) + 2;
-	cmd = xmalloc(sizeof(char) * l);
-	snprintf(cmd, l, DESCSTR, svc, *option ? "_" : "", option);
+	xasprintf(&cmd, DESCSTR, svc, *option ? "_" : "", option);
 	free(svc);
 	if ((fp = popen(cmd, "r"))) {
 		if (xgetline(&desc, &size, fp) == -1) {