1  /* integer_length - find most significant bit in an unsigned integer.
       2     Copyright (C) 2011-2021 Free Software Foundation, Inc.
       3  
       4     This file is free software: you can redistribute it and/or modify
       5     it under the terms of the GNU Lesser General Public License as
       6     published by the Free Software Foundation; either version 2.1 of the
       7     License, or (at your option) any later version.
       8  
       9     This file is distributed in the hope that it will be useful,
      10     but WITHOUT ANY WARRANTY; without even the implied warranty of
      11     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
      12     GNU Lesser General Public License for more details.
      13  
      14     You should have received a copy of the GNU Lesser General Public License
      15     along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
      16  
      17  /* Written by Bruno Haible <bruno@clisp.org>, 2011.  */
      18  
      19  #ifndef _INTEGER_LENGTH_H
      20  #define _INTEGER_LENGTH_H
      21  
      22  #ifdef __cplusplus
      23  extern "C" {
      24  #endif
      25  
      26  /* These functions return the minimum number of bits required to represent
      27     the given unsigned integer.
      28     For non-zero values, this is the position of the most significant bit
      29     that is set, plus one.  For zero, it is 0.  */
      30  
      31  /* Returns the integer length of x.
      32     The result is >= 0, <= sizeof (unsigned int) * CHAR_BIT.  */
      33  extern int integer_length (unsigned int x);
      34  
      35  /* Returns the integer length of x.
      36     The result is >= 0, <= sizeof (unsigned long) * CHAR_BIT.  */
      37  extern int integer_length_l (unsigned long x);
      38  
      39  /* Returns the integer length of x.
      40     The result is >= 0, <= sizeof (unsigned long long) * CHAR_BIT.  */
      41  extern int integer_length_ll (unsigned long long x);
      42  
      43  #ifdef __cplusplus
      44  }
      45  #endif
      46  
      47  #endif /* _INTEGER_LENGTH_H */