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#ifndef _LINUX_BYTEORDER_GENERIC_H
#define _LINUX_BYTEORDER_GENERIC_H
/*
* linux/byteorder_generic.h
* Generic Byte-reordering support
*
* The "... p" macros, like le64_to_cpup, can be used with pointers
* to unaligned data, but there will be a performance penalty on
* some architectures. Use get_unaligned for unaligned data.
*
* Francois-Rene Rideau <fare@tunes.org> 19970707
* gathered all the good ideas from all asm-foo/byteorder.h into one file,
* cleaned them up.
* I hope it is compliant with non-GCC compilers.
* I decided to put __BYTEORDER_HAS_U64__ in byteorder.h,
* because I wasn't sure it would be ok to put it in types.h
* Upgraded it to 2.1.43
* Francois-Rene Rideau <fare@tunes.org> 19971012
* Upgraded it to 2.1.57
* to please Linus T., replaced huge #ifdef's between little/big endian
* by nestedly #include'd files.
* Francois-Rene Rideau <fare@tunes.org> 19971205
* Made it to 2.1.71; now a facelift:
* Put files under include/linux/byteorder/
* Split swab from generic support.
*
* TODO:
* = Regular kernel maintainers could also replace all these manual
* byteswap macros that remain, disseminated among drivers,
* after some grep or the sources...
* = Linus might want to rename all these macros and files to fit his taste,
* to fit his personal naming scheme.
* = it seems that a few drivers would also appreciate
* nybble swapping support...
* = every architecture could add their byteswap macro in asm/byteorder.h
* see how some architectures already do (i386, alpha, ppc, etc)
* = cpu_to_beXX and beXX_to_cpu might some day need to be well
* distinguished throughout the kernel. This is not the case currently,
* since little endian, big endian, and pdp endian machines needn't it.
* But this might be the case for, say, a port of Linux to 20/21 bit
* architectures (and F21 Linux addict around?).
*/
/*
* The following macros are to be defined by <asm/byteorder.h>:
*
* Conversion of long and short int between network and host format
* ntohl(__u32 x)
* ntohs(__u16 x)
* htonl(__u32 x)
* htons(__u16 x)
* It seems that some programs (which? where? or perhaps a standard? POSIX?)
* might like the above to be functions, not macros (why?).
* if that's true, then detect them, and take measures.
* Anyway, the measure is: define only ___ntohl as a macro instead,
* and in a separate file, have
* unsigned long __inline__ ntohl(x){return ___ntohl(x);}
*
* The same for constant arguments
* __constant_ntohl(__u32 x)
* __constant_ntohs(__u16 x)
* __constant_htonl(__u32 x)
* __constant_htons(__u16 x)
*
* Conversion of XX-bit integers (16- 32- or 64-)
* between native CPU format and little/big endian format
* 64-bit stuff only defined for proper architectures
* cpu_to_[bl]eXX(__uXX x)
* [bl]eXX_to_cpu(__uXX x)
*
* The same, but takes a pointer to the value to convert
* cpu_to_[bl]eXXp(__uXX x)
* [bl]eXX_to_cpup(__uXX x)
*
* The same, but change in situ
* cpu_to_[bl]eXXs(__uXX x)
* [bl]eXX_to_cpus(__uXX x)
*
* See asm-foo/byteorder.h for examples of how to provide
* architecture-optimized versions
*
*/
#endif /* _LINUX_BYTEORDER_GENERIC_H */
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