1 ///////////////////////////////////////////////////////////////////////////////
4 /// \brief Byte swapping
6 // This code has been put into the public domain.
8 // This library is distributed in the hope that it will be useful,
9 // but WITHOUT ANY WARRANTY; without even the implied warranty of
10 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
12 ///////////////////////////////////////////////////////////////////////////////
17 // NOTE: We assume that config.h is already #included.
19 // At least glibc has byteswap.h which contains inline assembly code for
20 // byteswapping. Some systems have byteswap.h but lack one or more of the
21 // bswap_xx macros/functions, which is why we check them separately even
22 // if byteswap.h is available.
24 #ifdef HAVE_BYTESWAP_H
25 # include <byteswap.h>
29 # define bswap_16(num) \
30 (((num) << 8) | ((num) >> 8))
34 # define bswap_32(num) \
36 | (((num) << 8) & UINT32_C(0x00FF0000)) \
37 | (((num) >> 8) & UINT32_C(0x0000FF00)) \
42 # define bswap_64(num) \
44 | (((num) << 40) & UINT64_C(0x00FF000000000000)) \
45 | (((num) << 24) & UINT64_C(0x0000FF0000000000)) \
46 | (((num) << 8) & UINT64_C(0x000000FF00000000)) \
47 | (((num) >> 8) & UINT64_C(0x00000000FF000000)) \
48 | (((num) >> 24) & UINT64_C(0x0000000000FF0000)) \
49 | (((num) >> 40) & UINT64_C(0x000000000000FF00)) \