kc3-lang/libtommath/bn_mp_get_int.c

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• Hash : b0c385af
  Author :
  Date : 2014-09-23T22:54:30
  

  fix x32 compilation change mp_digit/mp_word to unsigned long long introduce new internal type mp_min_u32 that is minimum 32 bit wide x32 target is 64 bit arch but has 32 bit wide 'unsigned long'

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• bn_mp_get_int.c

• #include <tommath.h>
  #ifdef BN_MP_GET_INT_C
  /* LibTomMath, multiple-precision integer library -- Tom St Denis
   *
   * LibTomMath is a library that provides multiple-precision
   * integer arithmetic as well as number theoretic functionality.
   *
   * The library was designed directly after the MPI library by
   * Michael Fromberger but has been written from scratch with
   * additional optimizations in place.
   *
   * The library is free for all purposes without any express
   * guarantee it works.
   *
   * Tom St Denis, tomstdenis@gmail.com, http://libtom.org
   */
  
  /* get the lower 32-bits of an mp_int */
  unsigned long mp_get_int(mp_int * a)
  {
    int i;
    mp_min_u32 res;
  
    if (a->used == 0) {
       return 0;
    }
  
    /* get number of digits of the lsb we have to read */
    i = MIN(a->used,(int)((sizeof(unsigned long)*CHAR_BIT+DIGIT_BIT-1)/DIGIT_BIT))-1;
  
    /* get most significant digit of result */
    res = DIGIT(a,i);
  
    while (--i >= 0) {
      res = (res << DIGIT_BIT) | DIGIT(a,i);
    }
  
    /* force result to 32-bits always so it is consistent on non 32-bit platforms */
    return res & 0xFFFFFFFFUL;
  }
  #endif
  
  /* $Source$ */
  /* $Revision$ */
  /* $Date$ */
  

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