+/* If this pointer is non-zero, run the specified function upon each
+ allocation failure. It is initialized to zero. */
+extern void (*xalloc_fail_func) (void);
+
+/* If XALLOC_FAIL_FUNC is undefined or a function that returns, this
+ message is output. It is translated via gettext.
+ Its value is "memory exhausted". */
+extern char const xalloc_msg_memory_exhausted[];
+
+/* This function is always triggered when memory is exhausted. It is
+ in charge of honoring the two previous items. It exits with status
+ exit_failure (defined in exitfail.h). This is the
+ function to call when one wants the program to die because of a
+ memory allocation failure. */
+extern void xalloc_die (void) ATTRIBUTE_NORETURN;
+
+void *xmalloc (size_t n);
+void *xcalloc (size_t n, size_t s);
+void *xrealloc (void *p, size_t n);
+char *xstrdup (const char *str);
+
+# define XMALLOC(Type, N_items) xmalloc (sizeof (Type) * (N_items))
+# define XCALLOC(Type, N_items) xcalloc (sizeof (Type), N_items)
+# define XREALLOC(Ptr, Type, N_items) xrealloc (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)))