Add ib_uint32_t typedef.

include/univ.i

@@ -174,6 +174,16 @@ management to ensure correct alignment for doubles etc. */
 /* Note that inside MySQL 'byte' is defined as char on Linux! */
 #define byte			unsigned char
 
+/* Define an unsigned integer type that is exactly 32 bits. */
+
+#if SIZEOF_INT == 4
+typedef unsigned int		ib_uint32_t;
+#elif SIZEOF_LONG == 4
+typedef unsigned long		ib_uint32_t;
+#else
+#error "Neither int or long is 4 bytes"
+#endif
+
 /* Another basic type we use is unsigned long integer which should be equal to
 the word size of the machine, that is on a 32-bit platform 32 bits, and on a
 64-bit platform 64 bits. We also give the printf format for the type as a