/* SDL - Simple DirectMedia Layer Copyright (C) 1997-2012 Sam Lantinga This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. 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. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with this library; if not, write to the Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA Sam Lantinga slouken@libsdl.org*//** * @file SDL_endian.h * Functions for reading and writing endian-specific values */#ifndef _SDL_endian_h#define _SDL_endian_h#include "SDL_stdinc.h"/** @name SDL_ENDIANs * The two types of endianness *//*@{*/#define SDL_LIL_ENDIAN 1234#define SDL_BIG_ENDIAN 4321/*@}*/#ifndef SDL_BYTEORDER /* Not defined in SDL_config.h? */#ifdef __linux__#include <endian.h>#define SDL_BYTEORDER __BYTE_ORDER#else /* __linux __ */#if defined(__hppa__) || \ defined(__m68k__) || defined(mc68000) || defined(_M_M68K) || \ (defined(__MIPS__) && defined(__MISPEB__)) || \ defined(__ppc__) || defined(__POWERPC__) || defined(_M_PPC) || \ defined(__sparc__)#define SDL_BYTEORDER SDL_BIG_ENDIAN#else#define SDL_BYTEORDER SDL_LIL_ENDIAN#endif#endif /* __linux __ */#endif /* !SDL_BYTEORDER */#include "begin_code.h"/* Set up for C function definitions, even when using C++ */#ifdef __cplusplusextern "C" {#endif/** * @name SDL_Swap Functions * Use inline functions for compilers that support them, and static * functions for those that do not. Because these functions become * static for compilers that do not support inline functions, this * header should only be included in files that actually use them. *//*@{*/#if defined(__GNUC__) && defined(__i386__) && \ !(__GNUC__ == 2 && __GNUC_MINOR__ <= 95 /* broken gcc version */)static __inline__ Uint16 SDL_Swap16(Uint16 x){ __asm__("xchgb %b0,%h0" : "=q" (x) : "0" (x)); return x;}#elif defined(__GNUC__) && defined(__x86_64__)static __inline__ Uint16 SDL_Swap16(Uint16 x){ __asm__("xchgb %b0,%h0" : "=Q" (x) : "0" (x)); return x;}#elif defined(__GNUC__) && (defined(__powerpc__) || defined(__ppc__))static __inline__ Uint16 SDL_Swap16(Uint16 x){ Uint16 result; __asm__("rlwimi %0,%2,8,16,23" : "=&r" (result) : "0" (x >> 8), "r" (x)); return result;}#elif defined(__GNUC__) && (defined(__m68k__) && !defined(__mcoldfire__))static __inline__ Uint16 SDL_Swap16(Uint16 x){ __asm__("rorw #8,%0" : "=d" (x) : "0" (x) : "cc"); return x;}#elsestatic __inline__ Uint16 SDL_Swap16(Uint16 x) { return SDL_static_cast(Uint16, ((x<<8)|(x>>8)));}#endif#if defined(__GNUC__) && defined(__i386__) && \ !(__GNUC__ == 2 && __GNUC_MINOR__ <= 95 /* broken gcc version */)static __inline__ Uint32 SDL_Swap32(Uint32 x){ __asm__("bswap %0" : "=r" (x) : "0" (x)); return x;}#elif defined(__GNUC__) && defined(__x86_64__)static __inline__ Uint32 SDL_Swap32(Uint32 x){ __asm__("bswapl %0" : "=r" (x) : "0" (x)); return x;}#elif defined(__GNUC__) && (defined(__powerpc__) || defined(__ppc__))static __inline__ Uint32 SDL_Swap32(Uint32 x){ Uint32 result; __asm__("rlwimi %0,%2,24,16,23" : "=&r" (result) : "0" (x>>24), "r" (x)); __asm__("rlwimi %0,%2,8,8,15" : "=&r" (result) : "0" (result), "r" (x)); __asm__("rlwimi %0,%2,24,0,7" : "=&r" (result) : "0" (result), "r" (x)); return result;}#elif defined(__GNUC__) && (defined(__m68k__) && !defined(__mcoldfire__))static __inline__ Uint32 SDL_Swap32(Uint32 x){ __asm__("rorw #8,%0\n\tswap %0\n\trorw #8,%0" : "=d" (x) : "0" (x) : "cc"); return x;}#elsestatic __inline__ Uint32 SDL_Swap32(Uint32 x) { return SDL_static_cast(Uint32, ((x<<24)|((x<<8)&0x00FF0000)|((x>>8)&0x0000FF00)|(x>>24)));}#endif#ifdef SDL_HAS_64BIT_TYPE#if defined(__GNUC__) && defined(__i386__) && \ !(__GNUC__ == 2 && __GNUC_MINOR__ <= 95 /* broken gcc version */)static __inline__ Uint64 SDL_Swap64(Uint64 x){ union { struct { Uint32 a,b; } s; Uint64 u; } v; v.u = x; __asm__("bswapl %0 ; bswapl %1 ; xchgl %0,%1" : "=r" (v.s.a), "=r" (v.s.b) : "0" (v.s.a), "1" (v.s.b)); return v.u;}#elif defined(__GNUC__) && defined(__x86_64__)static __inline__ Uint64 SDL_Swap64(Uint64 x){ __asm__("bswapq %0" : "=r" (x) : "0" (x)); return x;}#elsestatic __inline__ Uint64 SDL_Swap64(Uint64 x){ Uint32 hi, lo; /* Separate into high and low 32-bit values and swap them */ lo = SDL_static_cast(Uint32, x & 0xFFFFFFFF); x >>= 32; hi = SDL_static_cast(Uint32, x & 0xFFFFFFFF); x = SDL_Swap32(lo); x <<= 32; x |= SDL_Swap32(hi); return (x);}#endif#else/* This is mainly to keep compilers from complaining in SDL code. * If there is no real 64-bit datatype, then compilers will complain about * the fake 64-bit datatype that SDL provides when it compiles user code. */#define SDL_Swap64(X) (X)#endif /* SDL_HAS_64BIT_TYPE *//*@}*//** * @name SDL_SwapLE and SDL_SwapBE Functions * Byteswap item from the specified endianness to the native endianness *//*@{*/#if SDL_BYTEORDER == SDL_LIL_ENDIAN#define SDL_SwapLE16(X) (X)#define SDL_SwapLE32(X) (X)#define SDL_SwapLE64(X) (X)#define SDL_SwapBE16(X) SDL_Swap16(X)#define SDL_SwapBE32(X) SDL_Swap32(X)#define SDL_SwapBE64(X) SDL_Swap64(X)#else#define SDL_SwapLE16(X) SDL_Swap16(X)#define SDL_SwapLE32(X) SDL_Swap32(X)#define SDL_SwapLE64(X) SDL_Swap64(X)#define SDL_SwapBE16(X) (X)#define SDL_SwapBE32(X) (X)#define SDL_SwapBE64(X) (X)#endif/*@}*//* Ends C function definitions when using C++ */#ifdef __cplusplus}#endif#include "close_code.h"#endif /* _SDL_endian_h */