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authorMatt Johnston <matt@ucc.asn.au>2007-02-03 08:20:34 +0000
committerMatt Johnston <matt@ucc.asn.au>2007-02-03 08:20:34 +0000
commitd9aeb2773e236e662c8b493f4bcee978f9908d7c (patch)
treebac48e388bf3ac739ae14cdf98da0eb4bb9d17bf /libtommath/bn_mp_clamp.c
parent056b92bd4c8a42ce1843493310d382159166edb8 (diff)
parentc5fd7dd5548f28e32d846e39d17e5c4de4e769af (diff)
merge of '5fdf69ca60d1683cdd9f4c2595134bed26394834'
and '6b61c50f4cf888bea302ac8fcf5dbb573b443251' --HG-- extra : convert_revision : b1dd3b94e60a07a176dba2b035ac79968595990a
Diffstat (limited to 'libtommath/bn_mp_clamp.c')
-rw-r--r--libtommath/bn_mp_clamp.c44
1 files changed, 44 insertions, 0 deletions
diff --git a/libtommath/bn_mp_clamp.c b/libtommath/bn_mp_clamp.c
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+++ b/libtommath/bn_mp_clamp.c
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+#include <tommath.h>
+#ifdef BN_MP_CLAMP_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
+ */
+
+/* trim unused digits
+ *
+ * This is used to ensure that leading zero digits are
+ * trimed and the leading "used" digit will be non-zero
+ * Typically very fast. Also fixes the sign if there
+ * are no more leading digits
+ */
+void
+mp_clamp (mp_int * a)
+{
+ /* decrease used while the most significant digit is
+ * zero.
+ */
+ while (a->used > 0 && a->dp[a->used - 1] == 0) {
+ --(a->used);
+ }
+
+ /* reset the sign flag if used == 0 */
+ if (a->used == 0) {
+ a->sign = MP_ZPOS;
+ }
+}
+#endif
+
+/* $Source: /cvs/libtom/libtommath/bn_mp_clamp.c,v $ */
+/* $Revision: 1.3 $ */
+/* $Date: 2006/03/31 14:18:44 $ */