1 #ifndef INCLUDED_ENDIAN_H
2 #define INCLUDED_ENDIAN_H
3 /* vim: set ts=8 sts=4 sw=4 tw=80 noet: */
4 /*======================================================================
5 Copyright (C) 2004,2005,2009,2012,2013 Walter Doekes
6   <walter+tthsum@wjd.nu>
7 This file is part of tthsum.
8 
9 tthsum is free software: you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation, either version 3 of the License, or
12 (at your option) any later version.
13 
14 tthsum is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17 GNU General Public License for more details.
18 
19 You should have received a copy of the GNU General Public License
20 along with tthsum.  If not, see <http://www.gnu.org/licenses/>.
21 ======================================================================*/
22 
23 /**
24  * Get byte order (endianness) for the host platform.
25  */
26 
27 /* Try to get BYTE_ORDER, BIG_ENDIAN and LITTLE_ENDIAN */
28 #if defined(__linux) || defined(__GLIBC__)
29 #   include <endian.h>
30 #   ifndef BIG_ENDIAN
31 #	define BIG_ENDIAN __BIG_ENDIAN
32 #   endif
33 #   ifndef LITTLE_ENDIAN
34 #	define LITTLE_ENDIAN __LITTLE_ENDIAN
35 #   endif
36 #   ifndef BYTE_ORDER
37 #	define BYTE_ORDER __BYTE_ORDER
38 #   endif
39 #elif defined(__FreeBSD__) || defined (__NetBSD__) || defined(__OpenBSD__)
40     /* sys/types.h includes machine/endian.h */
41 #   include <sys/types.h>
42 #   define LITTLE_ENDIAN _LITTLE_ENDIAN
43 #   define BIG_ENDIAN _BIG_ENDIAN
44 #endif /* !__*BSD__ */
45 
46 /* Test the values and try to set them by hand on failure */
47 #if LITTLE_ENDIAN == BIG_ENDIAN \
48 	    || (BYTE_ORDER != LITTLE_ENDIAN && BYTE_ORDER != BIG_ENDIAN) \
49 	    || !defined(BIG_ENDIAN) || !defined(LITTLE_ENDIAN)
50 #   undef BYTE_ORDER
51 #   undef BIG_ENDIAN
52 #   undef LITTLE_ENDIAN
53 #   define BIG_ENDIAN 4321
54 #   define LITTLE_ENDIAN 1234
55 #   if defined(__alpha) || defined(__i386__) || defined(__vax__) \
56 	    || defined(_WIN32)
57 #	define BYTE_ORDER LITTLE_ENDIAN
58 #   else
59 #	define BYTE_ORDER BIG_ENDIAN
60 #   endif
61 #endif
62 
63 #endif /* INCLUDED_ENDIAN_H */
64