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Diffstat (limited to 'src/SDL12/include/SDL_endian.h')
| -rw-r--r-- | src/SDL12/include/SDL_endian.h | 212 |
1 files changed, 212 insertions, 0 deletions
diff --git a/src/SDL12/include/SDL_endian.h b/src/SDL12/include/SDL_endian.h new file mode 100644 index 00000000..4fc2cf12 --- /dev/null +++ b/src/SDL12/include/SDL_endian.h @@ -0,0 +1,212 @@ +/* + SDL - Simple DirectMedia Layer + Copyright (C) 1997-2004 Sam Lantinga + + This library is free software; you can redistribute it and/or + modify it under the terms of the GNU Library General Public + License as published by the Free Software Foundation; either + version 2 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 + Library General Public License for more details. + + You should have received a copy of the GNU Library General Public + License along with this library; if not, write to the Free + Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + + Sam Lantinga + slouken@libsdl.org +*/ + +#ifdef SAVE_RCSID +static char rcsid = + "@(#) $Id: SDL_endian.h,v 1.15 2005/03/30 12:38:03 pmandin Exp $"; +#endif + +/* Functions for reading and writing endian-specific values */ + +#ifndef _SDL_endian_h +#define _SDL_endian_h + +/* These functions read and write data of the specified endianness, + dynamically translating to the host machine endianness. + + e.g.: If you want to read a 16 bit value on big-endian machine from + an open file containing little endian values, you would use: + value = SDL_ReadLE16(rp); + Note that the read/write functions use SDL_RWops pointers + instead of FILE pointers. This allows you to read and write + endian values from large chunks of memory as well as files + and other data sources. +*/ + +#include <stdio.h> + +#include "SDL_types.h" +#include "SDL_rwops.h" +#include "SDL_byteorder.h" + +#include "begin_code.h" +/* Set up for C function definitions, even when using C++ */ +#ifdef __cplusplus +extern "C" { +#endif + +/* 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__) +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(__M68000__) || defined(__M68020__)) +static __inline__ Uint16 SDL_Swap16(Uint16 x) +{ + __asm__("rorw #8,%0" : "=d" (x) : "0" (x) : "cc"); + return x; +} +#else +static __inline__ Uint16 SDL_Swap16(Uint16 x) { + return((x<<8)|(x>>8)); +} +#endif + +#if defined(__GNUC__) && defined(__i386__) +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(__M68000__) || defined(__M68020__)) +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; +} +#else +static __inline__ Uint32 SDL_Swap32(Uint32 x) { + return((x<<24)|((x<<8)&0x00FF0000)|((x>>8)&0x0000FF00)|(x>>24)); +} +#endif + +#ifdef SDL_HAS_64BIT_TYPE +#if defined(__GNUC__) && defined(__i386__) +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; +} +#else +static __inline__ Uint64 SDL_Swap64(Uint64 x) +{ + Uint32 hi, lo; + + /* Separate into high and low 32-bit values and swap them */ + lo = (Uint32)(x&0xFFFFFFFF); + x >>= 32; + hi = (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 */ + + +/* 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 + +/* Read an item of the specified endianness and return in native format */ +extern DECLSPEC Uint16 SDLCALL SDL_ReadLE16(SDL_RWops *src); +extern DECLSPEC Uint16 SDLCALL SDL_ReadBE16(SDL_RWops *src); +extern DECLSPEC Uint32 SDLCALL SDL_ReadLE32(SDL_RWops *src); +extern DECLSPEC Uint32 SDLCALL SDL_ReadBE32(SDL_RWops *src); +extern DECLSPEC Uint64 SDLCALL SDL_ReadLE64(SDL_RWops *src); +extern DECLSPEC Uint64 SDLCALL SDL_ReadBE64(SDL_RWops *src); + +/* Write an item of native format to the specified endianness */ +extern DECLSPEC int SDLCALL SDL_WriteLE16(SDL_RWops *dst, Uint16 value); +extern DECLSPEC int SDLCALL SDL_WriteBE16(SDL_RWops *dst, Uint16 value); +extern DECLSPEC int SDLCALL SDL_WriteLE32(SDL_RWops *dst, Uint32 value); +extern DECLSPEC int SDLCALL SDL_WriteBE32(SDL_RWops *dst, Uint32 value); +extern DECLSPEC int SDLCALL SDL_WriteLE64(SDL_RWops *dst, Uint64 value); +extern DECLSPEC int SDLCALL SDL_WriteBE64(SDL_RWops *dst, Uint64 value); + + +/* Ends C function definitions when using C++ */ +#ifdef __cplusplus +} +#endif +#include "close_code.h" + +#endif /* _SDL_endian_h */ |