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authorjan.nijtmans <nijtmans@users.sourceforge.net>2016-11-18 09:50:37 (GMT)
committerjan.nijtmans <nijtmans@users.sourceforge.net>2016-11-18 09:50:37 (GMT)
commitc85162575b2a6ba6d8b7103a103d8724c2d51e03 (patch)
treec945d6b5352f04dfb8dcda9435522ae38bf25c51 /libtommath/bn_mp_get_long.c
parente0c2fc16a8641c16944de458557edf2d315d688b (diff)
parent44774dc3238ca1e269c6acedcbdfb449780c96f9 (diff)
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Fix [e6f27aa56fa51bfc1752ce768bf0d301c60bfd2c|e6f27aa56f]: Update libtommath to 1.0
Diffstat (limited to 'libtommath/bn_mp_get_long.c')
-rw-r--r--libtommath/bn_mp_get_long.c41
1 files changed, 41 insertions, 0 deletions
diff --git a/libtommath/bn_mp_get_long.c b/libtommath/bn_mp_get_long.c
new file mode 100644
index 0000000..7c3d0fe
--- /dev/null
+++ b/libtommath/bn_mp_get_long.c
@@ -0,0 +1,41 @@
+#include <tommath_private.h>
+#ifdef BN_MP_GET_LONG_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, tstdenis82@gmail.com, http://libtom.org
+ */
+
+/* get the lower unsigned long of an mp_int, platform dependent */
+unsigned long mp_get_long(mp_int * a)
+{
+ int i;
+ unsigned long res;
+
+ if (a->used == 0) {
+ return 0;
+ }
+
+ /* get number of digits of the lsb we have to read */
+ i = MIN(a->used,(int)(((sizeof(unsigned long) * CHAR_BIT) + DIGIT_BIT - 1) / DIGIT_BIT)) - 1;
+
+ /* get most significant digit of result */
+ res = DIGIT(a,i);
+
+#if (ULONG_MAX != 0xffffffffuL) || (DIGIT_BIT < 32)
+ while (--i >= 0) {
+ res = (res << DIGIT_BIT) | DIGIT(a,i);
+ }
+#endif
+ return res;
+}
+#endif