44 lines
946 B
C
44 lines
946 B
C
/* LibTomMath, multiple-precision integer library -- Tom St Denis
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*
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* LibTomMath is a library that provides multiple-precision
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* integer arithmetic as well as number theoretic functionality.
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*
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* The library was 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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/* c = a mod b, 0 <= c < b */
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int
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mp_mod (mp_int * a, mp_int * b, mp_int * c)
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{
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mp_int t;
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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_div (a, b, NULL, &t)) != MP_OKAY) {
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mp_clear (&t);
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return res;
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}
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if (t.sign == MP_NEG) {
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res = mp_add (b, &t, c);
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} else {
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res = MP_OKAY;
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mp_exch (&t, c);
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}
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mp_clear (&t);
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return res;
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}
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