diff bn_mp_cmp_d.c @ 1:22d5cf7d4b1a libtommath

Renaming branch
author Matt Johnston <matt@ucc.asn.au>
date Mon, 31 May 2004 18:23:46 +0000
parents
children d29b64170cf0
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--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/bn_mp_cmp_d.c	Mon May 31 18:23:46 2004 +0000
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+/* 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, [email protected], http://math.libtomcrypt.org
+ */
+#include <tommath.h>
+
+/* compare a digit */
+int mp_cmp_d(mp_int * a, mp_digit b)
+{
+  /* compare based on sign */
+  if (a->sign == MP_NEG) {
+    return MP_LT;
+  }
+
+  /* compare based on magnitude */
+  if (a->used > 1) {
+    return MP_GT;
+  }
+
+  /* compare the only digit of a to b */
+  if (a->dp[0] > b) {
+    return MP_GT;
+  } else if (a->dp[0] < b) {
+    return MP_LT;
+  } else {
+    return MP_EQ;
+  }
+}