diff --git a/src/string.c b/src/string.c
index 754ca78..1fae4bc 100644
--- a/src/string.c
+++ b/src/string.c
@@ -180,19 +180,37 @@ bool
 cfw_string_set(CFWString *str, const char *cstr)
 {
 	char *copy;
+	size_t len;
 
-	if ((copy = cfw_strdup(cstr)) == NULL)
-		return false;
+	if (str != NULL) {
+		if ((copy = cfw_strdup(cstr)) == NULL)
+			return false;
+
+		len = strlen(copy);
+	} else {
+		copy = NULL;
+		len = 0;
+	}
 
 	if (str->data != NULL)
 		free(str->data);
 
 	str->data = copy;
-	str->len = strlen(copy);
+	str->len = len;
 
 	return true;
 }
 
+void
+cfw_string_set_nocopy(CFWString *str, char *cstr, size_t len)
+{
+	if (str->data != NULL)
+		free(str->data);
+
+	str->data = cstr;
+	str->len = len;
+}
+
 bool
 cfw_string_append(CFWString *str, CFWString *append)
 {
diff --git a/src/string.h b/src/string.h
index 87737c8..73d33c0 100644
--- a/src/string.h
+++ b/src/string.h
@@ -37,6 +37,7 @@ extern char* cfw_strndup(const char*, size_t);
 extern const char* cfw_string_c(CFWString*);
 extern size_t cfw_string_length(CFWString*);
 extern bool cfw_string_set(CFWString*, const char*);
+extern void cfw_string_set_nocopy(CFWString*, char*, size_t);
 extern bool cfw_string_append(CFWString*, CFWString*);
 extern size_t cfw_string_find(CFWString*, CFWString*, cfw_range_t);