kc3-lang/libtommath/mp_from_ubin.c

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• Hash : bcda8fc6
  Author :
  Date : 2019-10-29T22:38:49
  

  simplifications: remove unnecessary optimization * these double checks are not necessary * the compiler will move the early return outside of the called function, basically the functions is partially inlined * however lto/amalgamation needed for the optimization

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• mp_from_ubin.c

• #include "tommath_private.h"
  #ifdef MP_FROM_UBIN_C
  /* LibTomMath, multiple-precision integer library -- Tom St Denis */
  /* SPDX-License-Identifier: Unlicense */
  
  /* reads a uint8_t array, assumes the msb is stored first [big endian] */
  mp_err mp_from_ubin(mp_int *a, const uint8_t *buf, size_t size)
  {
     mp_err err;
  
     /* make sure there are at least two digits */
     if ((err = mp_grow(a, 2)) != MP_OKAY) {
        return err;
     }
  
     /* zero the int */
     mp_zero(a);
  
     /* read the bytes in */
     while (size-- > 0u) {
        if ((err = mp_mul_2d(a, 8, a)) != MP_OKAY) {
           return err;
        }
        a->dp[0] |= *buf++;
        a->used += 1;
     }
     mp_clamp(a);
     return MP_OKAY;
  }
  #endif
  

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