+/* This function is always triggered when memory is exhausted.
+ It must be defined by the application, either explicitly
+ or by using gnulib's xalloc-die module. 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 s) ATTRIBUTE_MALLOC;
+void *xzalloc (size_t s) ATTRIBUTE_MALLOC;
+void *xcalloc (size_t n, size_t s) ATTRIBUTE_MALLOC;
+void *xrealloc (void *p, size_t s);
+void *x2realloc (void *p, size_t *pn);
+void *xmemdup (void const *p, size_t s) ATTRIBUTE_MALLOC;
+char *xstrdup (char const *str) ATTRIBUTE_MALLOC;
+
+/* Return 1 if an array of N objects, each of size S, cannot exist due
+ to size arithmetic overflow. S must be positive and N must be
+ nonnegative. This is a macro, not an inline function, so that it
+ works correctly even when SIZE_MAX < N.
+
+ By gnulib convention, SIZE_MAX represents overflow in size
+ calculations, so the conservative dividend to use here is
+ SIZE_MAX - 1, since SIZE_MAX might represent an overflowed value.
+ However, malloc (SIZE_MAX) fails on all known hosts where
+ sizeof (ptrdiff_t) <= sizeof (size_t), so do not bother to test for
+ exactly-SIZE_MAX allocations on such hosts; this avoids a test and
+ branch when S is known to be 1. */
+# define xalloc_oversized(n, s) \
+ ((size_t) (sizeof (ptrdiff_t) <= sizeof (size_t) ? -1 : -2) / (s) < (n))
+
+
+/* In the following macros, T must be an elementary or structure/union or
+ typedef'ed type, or a pointer to such a type. To apply one of the
+ following macros to a function pointer or array type, you need to typedef
+ it first and use the typedef name. */
+
+/* Allocate an object of type T dynamically, with error checking. */
+/* extern t *XMALLOC (typename t); */
+# define XMALLOC(t) ((t *) xmalloc (sizeof (t)))
+
+/* Allocate memory for N elements of type T, with error checking. */
+/* extern t *XNMALLOC (size_t n, typename t); */
+# define XNMALLOC(n, t) \
+ ((t *) (sizeof (t) == 1 ? xmalloc (n) : xnmalloc (n, sizeof (t))))
+
+/* Allocate an object of type T dynamically, with error checking,
+ and zero it. */
+/* extern t *XZALLOC (typename t); */
+# define XZALLOC(t) ((t *) xzalloc (sizeof (t)))
+
+/* Allocate memory for N elements of type T, with error checking,
+ and zero it. */
+/* extern t *XCALLOC (size_t n, typename t); */
+# define XCALLOC(n, t) \
+ ((t *) (sizeof (t) == 1 ? xzalloc (n) : xcalloc (n, sizeof (t))))
+
+
+# if HAVE_INLINE
+# define static_inline static inline
+# else
+void *xnmalloc (size_t n, size_t s) ATTRIBUTE_MALLOC;
+void *xnrealloc (void *p, size_t n, size_t s);
+void *x2nrealloc (void *p, size_t *pn, size_t s);
+char *xcharalloc (size_t n) ATTRIBUTE_MALLOC;
+# endif
+
+# ifdef static_inline
+
+/* Allocate an array of N objects, each with S bytes of memory,
+ dynamically, with error checking. S must be nonzero. */
+
+static_inline void *xnmalloc (size_t n, size_t s) ATTRIBUTE_MALLOC;
+static_inline void *
+xnmalloc (size_t n, size_t s)
+{
+ if (xalloc_oversized (n, s))
+ xalloc_die ();
+ return xmalloc (n * s);
+}
+
+/* Change the size of an allocated block of memory P to an array of N
+ objects each of S bytes, with error checking. S must be nonzero. */