• endswap.h
  • /* libFLAC - Free Lossless Audio Codec library
     * Copyright (C) 2012-2025  Xiph.Org Foundation
     *
     * Redistribution and use in source and binary forms, with or without
     * modification, are permitted provided that the following conditions
     * are met:
     *
     * - Redistributions of source code must retain the above copyright
     * notice, this list of conditions and the following disclaimer.
     *
     * - Redistributions in binary form must reproduce the above copyright
     * notice, this list of conditions and the following disclaimer in the
     * documentation and/or other materials provided with the distribution.
     *
     * - Neither the name of the Xiph.org Foundation nor the names of its
     * contributors may be used to endorse or promote products derived from
     * this software without specific prior written permission.
     *
     * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
     * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
     * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
     * A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR
     * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
     * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
     * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
     * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
     * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
     * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
     * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     */
    
    /* It is assumed that this header will be included after "config.h". */
    
    #ifdef HAVE_BSWAP32			/* GCC and Clang */
    
    /* GCC prior to 4.8 didn't provide bswap16 on x86_64 */
    #ifndef HAVE_BSWAP16
    static inline unsigned short __builtin_bswap16(unsigned short a)
    {
    	return (a<<8)|(a>>8);
    }
    #endif
    
    #define	ENDSWAP_16(x)		(__builtin_bswap16 (x))
    #define	ENDSWAP_32(x)		(__builtin_bswap32 (x))
    #define	ENDSWAP_64(x)		(__builtin_bswap64 (x))
    
    #elif defined _MSC_VER		/* Windows */
    
    #include <stdlib.h>
    
    #define	ENDSWAP_16(x)		(_byteswap_ushort (x))
    #define	ENDSWAP_32(x)		(_byteswap_ulong (x))
    #define	ENDSWAP_64(x)		(_byteswap_uint64 (x))
    
    #elif defined HAVE_BYTESWAP_H		/* Linux */
    
    #include <byteswap.h>
    
    #define	ENDSWAP_16(x)		(bswap_16 (x))
    #define	ENDSWAP_32(x)		(bswap_32 (x))
    #define	ENDSWAP_64(x)		(bswap_64 (x))
    
    #else
    
    #define	ENDSWAP_16(x)		((((x) >> 8) & 0xFF) | (((x) & 0xFF) << 8))
    #define	ENDSWAP_32(x)		((((x) >> 24) & 0xFF) | (((x) >> 8) & 0xFF00) | (((x) & 0xFF00) << 8) | (((x) & 0xFF) << 24))
    #define	ENDSWAP_64(x)		((ENDSWAP_32(((x) >> 32) & 0xFFFFFFFF)) | (ENDSWAP_32((x) & 0xFFFFFFFF) << 32))
    
    #endif
    
    
    /* Host to little-endian byte swapping (for MD5 calculation) */
    #if CPU_IS_BIG_ENDIAN
    
    #define H2LE_16(x)		ENDSWAP_16 (x)
    #define H2LE_32(x)		ENDSWAP_32 (x)
    
    #else
    
    #define H2LE_16(x)		(x)
    #define H2LE_32(x)		(x)
    
    #endif