kc3-lang/libtommath/bn_mp_get_long.c

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• Hash : e45f75fd
  Author :
  Date : 2019-04-13T08:46:57
  

  deprecate DIGIT_BIT, use MP_DIGIT_BIT

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• bn_mp_get_long.c

• #include "tommath_private.h"
  #ifdef BN_MP_GET_LONG_C
  /* LibTomMath, multiple-precision integer library -- Tom St Denis */
  /* SPDX-License-Identifier: Unlicense */
  
  /* get the lower unsigned long of an mp_int, platform dependent */
  unsigned long mp_get_long(const mp_int *a)
  {
     int i;
     unsigned long res;
  
     if (MP_IS_ZERO(a)) {
        return 0;
     }
  
     /* get number of digits of the lsb we have to read */
     i = MP_MIN(a->used, (((CHAR_BIT * (int)sizeof(unsigned long)) + MP_DIGIT_BIT - 1) / MP_DIGIT_BIT)) - 1;
  
     /* get most significant digit of result */
     res = (unsigned long)a->dp[i];
  
  #if (ULONG_MAX != 0xFFFFFFFFUL) || (MP_DIGIT_BIT < 32)
     while (--i >= 0) {
        res = (res << MP_DIGIT_BIT) | (unsigned long)a->dp[i];
     }
  #endif
     return res;
  }
  #endif
  

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