+#if defined (HAVE_GETPWUID) && !defined (HAVE_GETPW_DECLS)
+extern struct passwd *getpwuid PARAMS((uid_t));
+#endif /* HAVE_GETPWUID && !HAVE_GETPW_DECLS */
+
+#ifndef NULL
+# define NULL 0
+#endif
+
+#ifndef CHAR_BIT
+# define CHAR_BIT 8
+#endif
+
+/* Nonzero if the integer type T is signed. */
+#define TYPE_SIGNED(t) (! ((t) 0 < (t) -1))
+
+/* Bound on length of the string representing an integer value of type T.
+ Subtract one for the sign bit if T is signed;
+ 302 / 1000 is log10 (2) rounded up;
+ add one for integer division truncation;
+ add one more for a minus sign if t is signed. */
+#define INT_STRLEN_BOUND(t) \
+ ((sizeof (t) * CHAR_BIT - TYPE_SIGNED (t)) * 302 / 1000 \
+ + 1 + TYPE_SIGNED (t))