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-rw-r--r--third_party/heimdal/lib/hcrypto/libtommath/bn_mp_clamp.c27
1 files changed, 27 insertions, 0 deletions
diff --git a/third_party/heimdal/lib/hcrypto/libtommath/bn_mp_clamp.c b/third_party/heimdal/lib/hcrypto/libtommath/bn_mp_clamp.c
new file mode 100644
index 0000000..ac23bfd
--- /dev/null
+++ b/third_party/heimdal/lib/hcrypto/libtommath/bn_mp_clamp.c
@@ -0,0 +1,27 @@
+#include "tommath_private.h"
+#ifdef BN_MP_CLAMP_C
+/* LibTomMath, multiple-precision integer library -- Tom St Denis */
+/* SPDX-License-Identifier: Unlicense */
+
+/* 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] == 0u)) {
+ --(a->used);
+ }
+
+ /* reset the sign flag if used == 0 */
+ if (a->used == 0) {
+ a->sign = MP_ZPOS;
+ }
+}
+#endif