32 lines
657 B
C
32 lines
657 B
C
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#include "tommath_private.h"
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#ifdef BN_MP_MOD_C
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/* LibTomMath, multiple-precision integer library -- Tom St Denis */
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/* SPDX-License-Identifier: Unlicense */
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/* c = a mod b, 0 <= c < b if b > 0, b < c <= 0 if b < 0 */
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mp_err mp_mod(const mp_int *a, const mp_int *b, mp_int *c)
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{
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mp_int t;
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mp_err err;
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if ((err = mp_init_size(&t, b->used)) != MP_OKAY) {
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return err;
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}
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if ((err = mp_div(a, b, NULL, &t)) != MP_OKAY) {
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goto LBL_ERR;
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}
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if (MP_IS_ZERO(&t) || (t.sign == b->sign)) {
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err = MP_OKAY;
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mp_exch(&t, c);
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} else {
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err = mp_add(b, &t, c);
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}
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LBL_ERR:
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mp_clear(&t);
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return err;
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}
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#endif
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