smartptr feature support - factor out common code

Source/CParse/cparse.h

@@ -57,6 +57,7 @@ extern "C" {
 
 /* util.c */
   extern void Swig_cparse_replace_descriptor(String *s);
+  extern SwigType *Swig_cparse_smartptr(Node *n);
   extern void cparse_normalize_void(Node *);
   extern Parm *Swig_cparse_parm(String *s);
   extern ParmList *Swig_cparse_parms(String *s, Node *file_line_node);

Source/CParse/util.c

@@ -70,6 +70,28 @@ void Swig_cparse_replace_descriptor(String *s) {
   }
 }
 
+/* -----------------------------------------------------------------------------
+ * Swig_cparse_smartptr()
+ *
+ * Parse the type in smartptr feature and convert into a SwigType.
+ * Error out if the parsing fails as this is like a parser syntax error.
+ * ----------------------------------------------------------------------------- */
+
+SwigType *Swig_cparse_smartptr(Node *n) {
+    SwigType *smart = 0;
+    String *smartptr = Getattr(n, "feature:smartptr");
+    if (smartptr) {
+      SwigType *cpt = Swig_cparse_type(smartptr);
+      if (cpt) {
+	smart = SwigType_typedef_resolve_all(cpt);
+	Delete(cpt);
+      } else {
+	Swig_error(Getfile(n), Getline(n), "Invalid type (%s) in 'smartptr' feature for class %s.\n", smartptr, SwigType_namestr(Getattr(n, "name")));
+      }
+    }
+    return smart;
+}
+
 /* -----------------------------------------------------------------------------
  * cparse_normalize_void()
  *