physfs/physfs_byteorder.c

119 lines
3.9 KiB
C

/**
* PhysicsFS; a portable, flexible file i/o abstraction.
*
* Documentation is in physfs.h. It's verbose, honest. :)
*
* Please see the file LICENSE in the source's root directory.
*
* This file written by Ryan C. Gordon.
*/
#include <stdio.h>
#include <stdlib.h>
#include <assert.h>
#include "physfs.h"
/* This byteorder stuff was lifted from SDL. http://www.libsdl.org/ */
#define PHYSFS_LIL_ENDIAN 1234
#define PHYSFS_BIG_ENDIAN 4321
#if defined(__i386__) || defined(__ia64__) || defined(WIN32) || \
(defined(__alpha__) || defined(__alpha)) || \
defined(__arm__) || \
(defined(__mips__) && defined(__MIPSEL__)) || \
defined(__SYMBIAN32__) || \
defined(__LITTLE_ENDIAN__)
#define PHYSFS_BYTEORDER PHYSFS_LIL_ENDIAN
#else
#define PHYSFS_BYTEORDER PHYSFS_BIG_ENDIAN
#endif
/* The macros used to swap values */
/* Try to use superfast macros on systems that support them */
#ifdef linux
#include <asm/byteorder.h>
#ifdef __arch__swab16
#define PHYSFS_Swap16 __arch__swab16
#endif
#ifdef __arch__swab32
#define PHYSFS_Swap32 __arch__swab32
#endif
#endif /* linux */
#if (defined _MSC_VER)
#define __inline__ __inline
#endif
#ifndef PHYSFS_Swap16
static __inline__ PHYSFS_uint16 PHYSFS_Swap16(PHYSFS_uint16 D)
{
return((D<<8)|(D>>8));
}
#endif
#ifndef PHYSFS_Swap32
static __inline__ PHYSFS_uint32 PHYSFS_Swap32(PHYSFS_uint32 D)
{
return((D<<24)|((D<<8)&0x00FF0000)|((D>>8)&0x0000FF00)|(D>>24));
}
#endif
#ifndef PHYSFS_NO_64BIT_SUPPORT
#ifndef PHYSFS_Swap64
static __inline__ PHYSFS_uint64 PHYSFS_Swap64(PHYSFS_uint64 val) {
PHYSFS_uint32 hi, lo;
/* Separate into high and low 32-bit values and swap them */
lo = (PHYSFS_uint32)(val&0xFFFFFFFF);
val >>= 32;
hi = (PHYSFS_uint32)(val&0xFFFFFFFF);
val = PHYSFS_Swap32(lo);
val <<= 32;
val |= PHYSFS_Swap32(hi);
return(val);
}
#endif
#else
#ifndef PHYSFS_Swap64
/* This is mainly to keep compilers from complaining in PHYSFS code.
If there is no real 64-bit datatype, then compilers will complain about
the fake 64-bit datatype that PHYSFS provides when it compiles user code.
*/
#define PHYSFS_Swap64(X) (X)
#endif
#endif /* PHYSFS_NO_64BIT_SUPPORT */
/* Byteswap item from the specified endianness to the native endianness */
#if PHYSFS_BYTEORDER == PHYSFS_LIL_ENDIAN
PHYSFS_uint16 PHYSFS_swapULE16(PHYSFS_uint16 x) { return(x); }
PHYSFS_sint16 PHYSFS_swapSLE16(PHYSFS_sint16 x) { return(x); }
PHYSFS_uint32 PHYSFS_swapULE32(PHYSFS_uint32 x) { return(x); }
PHYSFS_sint32 PHYSFS_swapSLE32(PHYSFS_sint32 x) { return(x); }
PHYSFS_uint64 PHYSFS_swapULE64(PHYSFS_uint64 x) { return(x); }
PHYSFS_sint64 PHYSFS_swapSLE64(PHYSFS_sint64 x) { return(x); }
PHYSFS_uint16 PHYSFS_swapUBE16(PHYSFS_uint16 x) { return(PHYSFS_Swap16(x)); }
PHYSFS_sint16 PHYSFS_swapSBE16(PHYSFS_sint16 x) { return(PHYSFS_Swap16(x)); }
PHYSFS_uint32 PHYSFS_swapUBE32(PHYSFS_uint32 x) { return(PHYSFS_Swap32(x)); }
PHYSFS_sint32 PHYSFS_swapSBE32(PHYSFS_sint32 x) { return(PHYSFS_Swap32(x)); }
PHYSFS_uint64 PHYSFS_swapUBE64(PHYSFS_uint64 x) { return(PHYSFS_Swap64(x)); }
PHYSFS_sint64 PHYSFS_swapSBE64(PHYSFS_sint64 x) { return(PHYSFS_Swap64(x)); }
#else
PHYSFS_uint16 PHYSFS_swapULE16(PHYSFS_uint16 x) { return(PHYSFS_Swap16(x)); }
PHYSFS_sint16 PHYSFS_swapSLE16(PHYSFS_sint16 x) { return(PHYSFS_Swap16(x)); }
PHYSFS_uint32 PHYSFS_swapULE32(PHYSFS_uint32 x) { return(PHYSFS_Swap32(x)); }
PHYSFS_sint32 PHYSFS_swapSLE32(PHYSFS_sint32 x) { return(PHYSFS_Swap32(x)); }
PHYSFS_uint64 PHYSFS_swapULE64(PHYSFS_uint64 x) { return(PHYSFS_Swap64(x)); }
PHYSFS_sint64 PHYSFS_swapSLE64(PHYSFS_sint64 x) { return(PHYSFS_Swap64(x)); }
PHYSFS_uint16 PHYSFS_swapUBE16(PHYSFS_uint16 x) { return(x); }
PHYSFS_sint16 PHYSFS_swapSBE16(PHYSFS_sint16 x) { return(x); }
PHYSFS_uint32 PHYSFS_swapUBE32(PHYSFS_uint32 x) { return(x); }
PHYSFS_sint32 PHYSFS_swapSBE32(PHYSFS_sint32 x) { return(x); }
PHYSFS_uint64 PHYSFS_swapUBE64(PHYSFS_uint64 x) { return(x); }
PHYSFS_sint64 PHYSFS_swapSBE64(PHYSFS_sint64 x) { return(x); }
#endif
/* end of physfs_byteorder.c ... */