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#include "tommath_private.h"
#ifdef BN_MP_FREAD_C
/* LibTomMath, multiple-precision integer library -- Tom St Denis */
/* SPDX-License-Identifier: Unlicense */
#ifndef MP_NO_FILE
/* read a bigint from a file stream in ASCII */
mp_err mp_fread(mp_int *a, int radix, FILE *stream)
{
mp_err err;
mp_sign neg;
/* if first digit is - then set negative */
int ch = fgetc(stream);
if (ch == (int)'-') {
neg = MP_NEG;
ch = fgetc(stream);
} else {
neg = MP_ZPOS;
}
/* no digits, return error */
if (ch == EOF) {
return MP_ERR;
}
/* clear a */
mp_zero(a);
do {
int y;
unsigned pos = (unsigned)(ch - (int)'(');
if (mp_s_rmap_reverse_sz < pos) {
break;
}
y = (int)mp_s_rmap_reverse[pos];
if ((y == 0xff) || (y >= radix)) {
break;
}
/* shift up and add */
if ((err = mp_mul_d(a, (mp_digit)radix, a)) != MP_OKAY) {
return err;
}
if ((err = mp_add_d(a, (mp_digit)y, a)) != MP_OKAY) {
return err;
}
} while ((ch = fgetc(stream)) != EOF);
if (a->used != 0) {
a->sign = neg;
}
return MP_OKAY;
}
#endif
#endif
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