1 files changed, 81 insertions, 0 deletions
diff --git a/libc/dfp/mapround.c b/libc/dfp/mapround.c
new file mode 100644
index 000000000..8835fcd61
--- /dev/null
+++ b/libc/dfp/mapround.c
@@ -0,0 +1,81 @@
+/* Get the Decimal Float rounding mode mapped to the decNumber rounding mode
+   enumeration values.
+
+   Copyright (C) 2006 IBM Corporation.
+   Author(s): Ryan S. Arnold <rsa@us.ibm.com>
+
+   The Decimal Floating Point C Library is free software; you can
+   redistribute it and/or modify it under the terms of the GNU Lesser
+   General Public License version 2.1.
+
+   The Decimal Floating Point C Library is distributed in the hope that
+   it will be useful, but WITHOUT ANY WARRANTY; without even the implied
+   warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
+   the GNU Lesser General Public License version 2.1 for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License version 2.1 along with the Decimal Floating Point C Library;
+   if not, write to the Free Software Foundation, Inc., 59 Temple Place,
+   Suite 330, Boston, MA 02111-1307 USA.
+
+   Please see dfp/COPYING.txt for more information.  */
+
+#include <fenv.h>
+#include <dfpfenv_private.h>
+#include <mapround.h>
+#include <decContext.h>
+
+int __dn_getround(void)
+{
+  /* Only match on supported rounding modes.  Power6[x] hardware supports the
+   * greatest number of rounding modes.  The decNumber library supports
+   * one fewer than Power6[x] hardware.  */
+
+  /* C Rounding Mode:		Hardware Description
+   * 				DecNumber description
+   *
+   * FE_DEC_TONEAREST:		000 Round to nearest, ties to even.
+   * 				DEC_ROUND_HALF_EVEN
+   *
+   * FE_DEC_TOWARDZERO:		001 Round toward zero.
+   * 				DEC_ROUND_DOWN
+   *
+   * FE_DEC_UPWARD:		010 Round toward +Infinity
+   * 				DEC_ROUND_CEILING
+   *
+   * FE_DEC_DOWNWARD:		011 Round toward -Infinity
+   * 				DEC_ROUND_FLOOR
+   *
+   * FE_DEC_TONEARESTFROMZERO:	100 Round to nearest, ties away from zero
+   * 				DEC_ROUND_HALF_UP
+   *
+   * 5:				101 Round to nearest, ties toward zero
+   * 				DEC_ROUND_HALF_DOWN
+   *
+   * 6:				110 Round away from zero
+   * 				DEC_ROUND_UP
+   *
+   * 7:				111 Round for prepare for shorter precision
+   * 				Not supported by decNumber.  */
+
+  switch(__fe_dec_getround())
+    {
+      case FE_DEC_TONEAREST:
+	return DEC_ROUND_HALF_EVEN;
+      case FE_DEC_TOWARDZERO:
+	return DEC_ROUND_DOWN;
+      case FE_DEC_UPWARD:
+	return DEC_ROUND_CEILING;
+      case FE_DEC_DOWNWARD:
+	return DEC_ROUND_FLOOR;
+      case FE_DEC_TONEARESTFROMZERO:
+	return DEC_ROUND_HALF_UP;
+      case 5:
+	return DEC_ROUND_HALF_DOWN;
+      case 6:
+	return DEC_ROUND_UP;
+      case 7:
+      default:
+	return DEC_ROUND_HALF_EVEN;
+    }
+}