version 0.3.33

[fms.git] / libs / libtommath / bn_mp_set_int.c

diff --git a/libs/libtommath/bn_mp_set_int.c b/libs/libtommath/bn_mp_set_int.c
new file mode 100644 (file)
index 0000000..35e844f
--- /dev/null
+++ b/libs/libtommath/bn_mp_set_int.c
@@ -0,0 +1,48 @@
+#include <tommath.h>
+#ifdef BN_MP_SET_INT_C
+/* LibTomMath, multiple-precision integer library -- Tom St Denis
+ *
+ * LibTomMath is a library that provides multiple-precision
+ * integer arithmetic as well as number theoretic functionality.
+ *
+ * The library was designed directly after the MPI library by
+ * Michael Fromberger but has been written from scratch with
+ * additional optimizations in place.
+ *
+ * The library is free for all purposes without any express
+ * guarantee it works.
+ *
+ * Tom St Denis, tomstdenis@gmail.com, http://math.libtomcrypt.com
+ */
+
+/* set a 32-bit const */
+int mp_set_int (mp_int * a, unsigned long b)
+{
+  int     x, res;
+
+  mp_zero (a);
+  
+  /* set four bits at a time */
+  for (x = 0; x < 8; x++) {
+    /* shift the number up four bits */
+    if ((res = mp_mul_2d (a, 4, a)) != MP_OKAY) {
+      return res;
+    }
+
+    /* OR in the top four bits of the source */
+    a->dp[0] |= (b >> 28) & 15;
+
+    /* shift the source up to the next four bits */
+    b <<= 4;
+
+    /* ensure that digits are not clamped off */
+    a->used += 1;
+  }
+  mp_clamp (a);
+  return MP_OKAY;
+}
+#endif
+
+/* $Source: /cvs/libtom/libtommath/bn_mp_set_int.c,v $ */
+/* $Revision: 1.3 $ */
+/* $Date: 2006/03/31 14:18:44 $ */