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authorMatt Johnston <matt@ucc.asn.au>2006-03-08 13:16:18 +0000
committerMatt Johnston <matt@ucc.asn.au>2006-03-08 13:16:18 +0000
commit1c5fda515f96c27d4e3b732d887f418453f1cb14 (patch)
treebf90196389a9618de48c5acb5ce1d056aa347ce0 /bn_mp_neg.c
Import of libtommath 0.35
From ltm-0.35.tar.bz2 SHA1 of 3f193dbae9351e92d02530994fa18236f7fde01c --HG-- branch : libtommath-orig extra : convert_revision : 2b4b13ac88b2a81e5c86ba868c92c6a452630e02
Diffstat (limited to 'bn_mp_neg.c')
-rw-r--r--bn_mp_neg.c36
1 files changed, 36 insertions, 0 deletions
diff --git a/bn_mp_neg.c b/bn_mp_neg.c
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--- /dev/null
+++ b/bn_mp_neg.c
@@ -0,0 +1,36 @@
+#include <tommath.h>
+#ifdef BN_MP_NEG_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@iahu.ca, http://math.libtomcrypt.org
+ */
+
+/* b = -a */
+int mp_neg (mp_int * a, mp_int * b)
+{
+ int res;
+ if (a != b) {
+ if ((res = mp_copy (a, b)) != MP_OKAY) {
+ return res;
+ }
+ }
+
+ if (mp_iszero(b) != MP_YES) {
+ b->sign = (a->sign == MP_ZPOS) ? MP_NEG : MP_ZPOS;
+ } else {
+ b->sign = MP_ZPOS;
+ }
+
+ return MP_OKAY;
+}
+#endif