Initial commit

1 files changed, 49 insertions, 0 deletions

diff --git a/sys/osb/shift.c b/sys/osb/shift.c
new file mode 100644
index 00000000..86eacfb3
--- /dev/null
+++ b/sys/osb/shift.c
@@ -0,0 +1,49 @@
+/* Copyright(c) 1986 Association of Universities for Research in Astronomy Inc.
+ */
+
+#define	import_spp
+#define import_knames
+#include <iraf.h>
+
+/*
+ * SHIFT.C -- Bitwise shift operators.  A positive bitshift shifts to the left,
+ * zero-filling at the right, i.e., a left shift by 1 is equivalent to a
+ * multiplication by 2 (but does not cause integer overflow).  A negative shift
+ * shifts to the right and is equivalent to a division.
+ */
+
+/* SHIFTI -- Bitwise boolean SHIFT of two integer variables.
+ */
+XINT
+SHIFTI (
+  XINT	*a_a,			/* operand to be shifted	*/
+  XINT	*a_bits 		/* number of bits to shift	*/
+)
+{
+	register XINT	a = *a_a, bits = *a_bits;
+	return (bits > 0 ? (a << bits) : (a >> -bits));
+}
+
+/* SHIFTS -- Bitwise boolean SHIFT of two short-integer variables.
+ */
+XSHORT
+SHIFTS (
+  XSHORT *a_a,			/* operand to be shifted	*/
+  XSHORT *a_bits 		/* number of bits to shift	*/
+)
+{
+	register XSHORT	a = *a_a, bits = *a_bits;
+	return (bits > 0 ? (a << bits) : (a >> -bits));
+}
+
+/* SHIFTL -- Bitwise boolean SHIFT of two long-integer variables.
+ */
+XLONG
+SHIFTL (
+  XLONG	*a_a,			/* operand to be shifted	*/
+  XLONG	*a_bits 		/* number of bits to shift	*/
+)
+{
+	register XLONG	a = *a_a, bits = *a_bits;
+	return (bits > 0 ? (a << bits) : (a >> -bits));
+}