Maybe some minor changes.

util/led/byte_order.c

@@ -0,0 +1,90 @@
+#ifndef lint
+static char rcsid[] = "$Header$";
+#endif lint
+
+#include "const.h"
+#include "assert.h"
+
+bool	bytes_reversed = FALSE;
+bool	words_reversed = FALSE;
+
+/*
+ * Determine the byte/word order in shorts/longs, assuming the size of a short
+ * is 2 chars, and the size of a long is 4 chars. Not all theoretical
+ * possibilities are tested; only bytes reversed and/or words reversed.
+ */
+determine_ordering()
+{
+	short	s;
+	long	l;
+	register char	*cp;
+	register short	*sp;
+
+	cp = (char *)&s;
+	cp[0] = 0x01; cp[1] = 0x02;
+	if (s != 0x01 + (0x02 << 8))
+		bytes_reversed = TRUE;
+	sp = (short *)&l;
+	sp[0] = 0x0001; sp[1] = 0x0002;
+	if (l != 0x0001 + (0x0002 << 16))
+		words_reversed = TRUE;
+}
+
+/*
+ * `Format' is a string of digits indicating how many bytes must be taken
+ * from `buf' to form an integer of some type. E.g. if the digit is '2', two
+ * bytes are taken to form a short.
+ */
+swap(buf, format)
+	register char	*buf;
+	register char	*format;
+{
+	register char	savebyte;
+
+	while (*format) {
+		switch (*format++) {
+		case '1':
+			buf += 1;
+			break;
+		case '2':
+			if (bytes_reversed) {
+				savebyte = buf[0];
+				buf[0] = buf[1];
+				buf[1] = savebyte;
+			}
+			buf += 2;
+			break;
+		case '4':
+			/*
+			 * Written out to save recursive calls.
+			 */
+			if (bytes_reversed && words_reversed) {
+				savebyte = buf[0];
+				buf[0] = buf[3];
+				buf[3] = savebyte;
+				savebyte = buf[1];
+				buf[1] = buf[2];
+				buf[2] = savebyte;
+			} else if (bytes_reversed) {
+				savebyte = buf[0];
+				buf[0] = buf[1];
+				buf[1] = savebyte;
+				savebyte = buf[2];
+				buf[2] = buf[3];
+				buf[3] = savebyte;
+			} else if (words_reversed) {
+				savebyte = buf[0];
+				buf[0] = buf[2];
+				buf[2] = savebyte;
+				savebyte = buf[1];
+				buf[1] = buf[3];
+				buf[3] = savebyte;
+			}
+			buf += 4;
+			break;
+		default:
+			assert(FALSE);
+			break;
+		}
+	}
+}