-# define XMALLOC(Type, N_bytes) ((Type *) xmalloc (sizeof (Type) * (N_bytes)))
-# define XCALLOC(Type, N_bytes) ((Type *) xcalloc (sizeof (Type), (N_bytes)))
-# define XREALLOC(Ptr, Type, N_bytes) \
- ((Type *) xrealloc ((void *) (Ptr), sizeof (Type) * (N_bytes)))
+# define XMALLOC(Type, N_items) ((Type *) xmalloc (sizeof (Type) * (N_items)))
+# define XCALLOC(Type, N_items) ((Type *) xcalloc (sizeof (Type), (N_items)))
+# define XREALLOC(Ptr, Type, N_items) \
+ ((Type *) xrealloc ((void *) (Ptr), sizeof (Type) * (N_items)))
+
+/* Declare and alloc memory for VAR of type TYPE. */
+# define NEW(Type, Var) Type *(Var) = XMALLOC (Type, 1)
+
+/* Free VAR only if non NULL. */
+# define XFREE(Var) \
+ do { \
+ if (Var) \
+ free (Var); \
+ } while (0)
+
+/* Return a pointer to a malloc'ed copy of the array SRC of NUM elements. */
+# define CCLONE(Src, Num) \
+ (memcpy (xmalloc (sizeof (*Src) * (Num)), (Src), sizeof (*Src) * (Num)))
+
+/* Return a malloc'ed copy of SRC. */
+# define CLONE(Src) CCLONE (Src, 1)
+