1  /* Endian macros for string.h functions
       2     Copyright (C) 1992-2023 Free Software Foundation, Inc.
       3     This file is part of the GNU C Library.
       4  
       5     The GNU C Library is free software; you can redistribute it and/or
       6     modify it under the terms of the GNU Lesser General Public
       7     License as published by the Free Software Foundation; either
       8     version 2.1 of the License, or (at your option) any later version.
       9  
      10     The GNU C Library is distributed in the hope that it will be useful,
      11     but WITHOUT ANY WARRANTY; without even the implied warranty of
      12     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
      13     Lesser General Public License for more details.
      14  
      15     You should have received a copy of the GNU Lesser General Public
      16     License along with the GNU C Library; if not, see
      17     <http://www.gnu.org/licenses/>.  */
      18  
      19  #ifndef _BITS_ENDIAN_H
      20  #define _BITS_ENDIAN_H 1
      21  
      22  /* Definitions for byte order, according to significance of bytes,
      23     from low addresses to high addresses.  The value is what you get by
      24     putting '4' in the most significant byte, '3' in the second most
      25     significant byte, '2' in the second least significant byte, and '1'
      26     in the least significant byte, and then writing down one digit for
      27     each byte, starting with the byte at the lowest address at the left,
      28     and proceeding to the byte with the highest address at the right.  */
      29  
      30  #define	__LITTLE_ENDIAN	1234
      31  #define	__BIG_ENDIAN	4321
      32  #define	__PDP_ENDIAN	3412
      33  
      34  /* This file defines `__BYTE_ORDER' for the particular machine.  */
      35  #include <bits/endianness.h>
      36  
      37  /* Some machines may need to use a different endianness for floating point
      38     values.  */
      39  #ifndef __FLOAT_WORD_ORDER
      40  # define __FLOAT_WORD_ORDER __BYTE_ORDER
      41  #endif
      42  
      43  #if __BYTE_ORDER == __LITTLE_ENDIAN
      44  # define __LONG_LONG_PAIR(HI, LO) LO, HI
      45  #elif __BYTE_ORDER == __BIG_ENDIAN
      46  # define __LONG_LONG_PAIR(HI, LO) HI, LO
      47  #endif
      48  
      49  #endif /* bits/endian.h */