libctf/swap.h

   1 /* Interface to byteswapping functions.
   2    Copyright (C) 2006-2019 Free Software Foundation, Inc.
   3
   4    This file is part of libctf.
   5
   6    libctf is free software; you can redistribute it and/or modify it under
   7    the terms of the GNU General Public License as published by the Free
   8    Software Foundation; either version 3, or (at your option) any later
   9    version.
  10
  11    This program is distributed in the hope that it will be useful, but
  12    WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  14    See the GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program; see the file COPYING.  If not see
  18    <http://www.gnu.org/licenses/>.  */
  19
  20 #ifndef _CTF_SWAP_H
  21 #define _CTF_SWAP_H
  22
  23 #include "config.h"
  24 #include <stdint.h>
  25
  26 #ifdef HAVE_BYTESWAP_H
  27 #include <byteswap.h>
  28 #else
  29
  30 /* Provide our own versions of the byteswap functions.  */
  31 static inline uint16_t
  32 bswap_16 (uint16_t v)
  33 {
  34   return ((v >> 8) & 0xff) | ((v & 0xff) << 8);
  35 }
  36
  37 static inline uint32_t
  38 bswap_32 (uint32_t v)
  39 {
  40   return (  ((v & 0xff000000) >> 24)
  41           | ((v & 0x00ff0000) >>  8)
  42           | ((v & 0x0000ff00) <<  8)
  43           | ((v & 0x000000ff) << 24));
  44 }
  45
  46 inline uint64_t
  47 bswap_identity_64 (uint64_t v)
  48 {
  49   return v;
  50 }
  51
  52 static inline uint64_t
  53 bswap_64 (uint64_t v)
  54 {
  55   return (  ((v & 0xff00000000000000ULL) >> 56)
  56           | ((v & 0x00ff000000000000ULL) >> 40)
  57           | ((v & 0x0000ff0000000000ULL) >> 24)
  58           | ((v & 0x000000ff00000000ULL) >>  8)
  59           | ((v & 0x00000000ff000000ULL) <<  8)
  60           | ((v & 0x0000000000ff0000ULL) << 24)
  61           | ((v & 0x000000000000ff00ULL) << 40)
  62           | ((v & 0x00000000000000ffULL) << 56));
  63 }
  64 #endif /* !defined(HAVE_BYTESWAP_H) */
  65
  66 #endif /* !defined(_CTF_SWAP_H) */