log.h

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/******************************************************************************
The MIT License(MIT)

Embedded Template Library.

Copyright(c) 2014 jwellbelove

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#ifndef __ETL_LOG__
#define __ETL_LOG__

#include <stddef.h>


namespace etl 
{
  //***************************************************************************
  //***************************************************************************
  template <const size_t N, const size_t BASE>
  struct log
  {
    enum value_type
    {
      // Recursive definition.
      value = (N >= BASE) ? 1 + log<N / BASE, BASE>::value : 0
    };
  };

  //***************************************************************************
  // Specialisation for N = 1
  //***************************************************************************
  template <const size_t BASE>
  struct log<1, BASE>
  {
    enum value_type
    {
      value = 0
    };
  };

  //***************************************************************************
  // Specialisation for N = 0
  //***************************************************************************
  template <const size_t BASE>
  struct log<0, BASE>
  {
    enum value_type
    {
      value = 0
    };
  };

  //***************************************************************************
  //***************************************************************************
  template <const size_t N>
  struct log2
  {
    enum value_type
    {
      value = log<N, 2>::value
    };
  };

  //***************************************************************************
  //***************************************************************************
  template <const size_t N>
  struct log10
  {
    enum value_type
    {
      value = log<N, 10>::value
    };
  };
}

#endif