Added resize method used to re-alloc a DataBlock if it doesn't have a required length.

git-svn-id: http://yate.null.ro/svn/yate/trunk@3762 acf43c95-373e-0410-b603-e72c3f656dc1

yateclass.h

@@ -2854,6 +2854,15 @@ public:
      */
     void insert(const DataBlock& value);
 
+    /**
+     * Resize (re-alloc or free) this block if required size is not the same as the current one
+     * @param len Required block size
+     */
+    inline void resize(unsigned int len) {
+	    if (len != length())
+		assign(0,len);
+	}
+
     /**
      * Truncate the data block
      * @param len The maximum length to keep