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-rw-r--r--libtommath/bn_mp_get_long_long.c41
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diff --git a/libtommath/bn_mp_get_long_long.c b/libtommath/bn_mp_get_long_long.c
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+++ b/libtommath/bn_mp_get_long_long.c
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+#include <tommath_private.h>
+#ifdef BN_MP_GET_LONG_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 long of an mp_int, platform dependent */
+unsigned long long mp_get_long_long (mp_int * a)
+{
+ int i;
+ unsigned long 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 long) * CHAR_BIT) + DIGIT_BIT - 1) / DIGIT_BIT)) - 1;
+
+ /* get most significant digit of result */
+ res = DIGIT(a,i);
+
+#if DIGIT_BIT < 64
+ while (--i >= 0) {
+ res = (res << DIGIT_BIT) | DIGIT(a,i);
+ }
+#endif
+ return res;
+}
+#endif