48 lines
1.0 KiB
C
48 lines
1.0 KiB
C
/* LibTomMath, multiple-precision integer library -- Tom St Denis
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*
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* LibTomMath is library that provides for multiple-precision
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* integer arithmetic as well as number theoretic functionality.
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*
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* The library is designed directly after the MPI library by
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* Michael Fromberger but has been written from scratch with
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* additional optimizations in place.
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*
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* The library is free for all purposes without any express
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* guarantee it works.
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*
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* Tom St Denis, tomstdenis@iahu.ca, http://math.libtomcrypt.org
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*/
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#include <tommath.h>
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int
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mp_mod_d (mp_int * a, mp_digit b, mp_digit * c)
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{
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mp_int t, t2;
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int res;
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if ((res = mp_init (&t)) != MP_OKAY) {
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return res;
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}
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if ((res = mp_init (&t2)) != MP_OKAY) {
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mp_clear (&t);
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return res;
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}
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mp_set (&t, b);
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mp_div (a, &t, NULL, &t2);
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if (t2.sign == MP_NEG) {
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if ((res = mp_add_d (&t2, b, &t2)) != MP_OKAY) {
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mp_clear (&t);
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mp_clear (&t2);
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return res;
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}
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}
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*c = t2.dp[0];
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mp_clear (&t);
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mp_clear (&t2);
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return MP_OKAY;
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}
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