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Diffstat (limited to 'src/common/bswap.h')
-rw-r--r-- | src/common/bswap.h | 44 |
1 files changed, 44 insertions, 0 deletions
diff --git a/src/common/bswap.h b/src/common/bswap.h new file mode 100644 index 00000000..8f82a8f4 --- /dev/null +++ b/src/common/bswap.h @@ -0,0 +1,44 @@ +/////////////////////////////////////////////////////////////////////////////// +// +/// \file bswap.h +/// \brief Byte swapping +// +// This code has been put into the public domain. +// +// This library is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. +// +/////////////////////////////////////////////////////////////////////////////// + +#ifndef LZMA_BSWAP_H +#define LZMA_BSWAP_H + +// NOTE: We assume that config.h is already #included. + +// byteswap.h is a GNU extension. It contains inline assembly versions +// for byteswapping. When byteswap.h is not available, we use generic code. +#ifdef HAVE_BYTESWAP_H +# include <byteswap.h> +#else +# define bswap_16(num) \ + (((num) << 8) | ((num) >> 8)) + +# define bswap_32(num) \ + ( (((num) << 24) ) \ + | (((num) << 8) & UINT32_C(0x00FF0000)) \ + | (((num) >> 8) & UINT32_C(0x0000FF00)) \ + | (((num) >> 24) ) ) + +# define bswap_64(num) \ + ( (((num) << 56) ) \ + | (((num) << 40) & UINT64_C(0x00FF000000000000)) \ + | (((num) << 24) & UINT64_C(0x0000FF0000000000)) \ + | (((num) << 8) & UINT64_C(0x000000FF00000000)) \ + | (((num) >> 8) & UINT64_C(0x00000000FF000000)) \ + | (((num) >> 24) & UINT64_C(0x0000000000FF0000)) \ + | (((num) >> 40) & UINT64_C(0x000000000000FF00)) \ + | (((num) >> 56) ) ) +#endif + +#endif |