Initial commit

1 files changed, 38 insertions, 0 deletions

diff --git a/sys/osb/bswap2.c b/sys/osb/bswap2.c
new file mode 100644
index 00000000..a2c08030
--- /dev/null
+++ b/sys/osb/bswap2.c
@@ -0,0 +1,38 @@
+/* Copyright(c) 1986 Association of Universities for Research in Astronomy Inc.
+ */
+
+#define	import_spp
+#define import_knames
+#include <iraf.h>
+
+/* BSWAP2 - Move bytes from array "a" to array "b", swapping successive
+ * pairs of bytes.  The two arrays may be the same but may not be offset
+ * and overlapping.
+ */
+BSWAP2 (a, aoff, b, boff, nbytes)
+XCHAR	*a;			/* input array			*/
+XINT	*aoff;			/* first byte in input array	*/
+XCHAR	*b;			/* output array			*/
+XINT	*boff;			/* first byte in output array	*/
+XINT	*nbytes;		/* number of bytes to swap	*/
+{
+	register char *ip, *op, *otop;
+	register unsigned temp;
+
+	ip = (char *)a + *aoff - 1;
+	op = (char *)b + *boff - 1;
+	otop = op + (*nbytes & ~1);
+
+	/* Swap successive pairs of bytes.
+	 */
+	while (op < otop) {
+	    temp  = *ip++;
+	    *op++ = *ip++;
+	    *op++ = temp;
+	}
+
+	/* If there is an odd byte left, move it to the output array.
+	 */
+	if (*nbytes & 1)
+	    *op = *ip;
+}