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      1 /* libFLAC - Free Lossless Audio Codec library
      2  * Copyright (C) 2012-2014  Xiph.org Foundation
      3  *
      4  * Redistribution and use in source and binary forms, with or without
      5  * modification, are permitted provided that the following conditions
      6  * are met:
      7  *
      8  * - Redistributions of source code must retain the above copyright
      9  * notice, this list of conditions and the following disclaimer.
     10  *
     11  * - Redistributions in binary form must reproduce the above copyright
     12  * notice, this list of conditions and the following disclaimer in the
     13  * documentation and/or other materials provided with the distribution.
     14  *
     15  * - Neither the name of the Xiph.org Foundation nor the names of its
     16  * contributors may be used to endorse or promote products derived from
     17  * this software without specific prior written permission.
     18  *
     19  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
     20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
     21  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
     22  * A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR
     23  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
     24  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
     25  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
     26  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
     27  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
     28  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
     29  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     30  */
     31 
     32 /* It is assumed that this header will be included after "config.h". */
     33 
     34 #if HAVE_BSWAP32			/* GCC and Clang */
     35 
     36 /* GCC prior to 4.8 didn't provide bswap16 on x86_64 */
     37 #if ! HAVE_BSWAP16
     38 static inline unsigned short __builtin_bswap16(unsigned short a)
     39 {
     40 	return (a<<8)|(a>>8);
     41 }
     42 #endif
     43 
     44 #define	ENDSWAP_16(x)		(__builtin_bswap16 (x))
     45 #define	ENDSWAP_32(x)		(__builtin_bswap32 (x))
     46 
     47 #elif defined _MSC_VER		/* Windows. Apparently in <stdlib.h>. */
     48 
     49 #define	ENDSWAP_16(x)		(_byteswap_ushort (x))
     50 #define	ENDSWAP_32(x)		(_byteswap_ulong (x))
     51 
     52 #elif defined HAVE_BYTESWAP_H		/* Linux */
     53 
     54 #include <byteswap.h>
     55 
     56 #define	ENDSWAP_16(x)		(bswap_16 (x))
     57 #define	ENDSWAP_32(x)		(bswap_32 (x))
     58 
     59 #else
     60 
     61 #define	ENDSWAP_16(x)		((((x) >> 8) & 0xFF) | (((x) & 0xFF) << 8))
     62 #define	ENDSWAP_32(x)		((((x) >> 24) & 0xFF) | (((x) >> 8) & 0xFF00) | (((x) & 0xFF00) << 8) | (((x) & 0xFF) << 24))
     63 
     64 #endif
     65 
     66 
     67 /* Host to little-endian byte swapping. */
     68 #if CPU_IS_BIG_ENDIAN
     69 
     70 #define H2LE_16(x)		ENDSWAP_16 (x)
     71 #define H2LE_32(x)		ENDSWAP_32 (x)
     72 
     73 #else
     74 
     75 #define H2LE_16(x)		(x)
     76 #define H2LE_32(x)		(x)
     77 
     78 #endif
     79