1 #ifndef _LINUX_BYTEORDER_GENERIC_H 2 #define _LINUX_BYTEORDER_GENERIC_H 3 4 /* 5 * linux/byteorder_generic.h 6 * Generic Byte-reordering support 7 * 8 * The "... p" macros, like le64_to_cpup, can be used with pointers 9 * to unaligned data, but there will be a performance penalty on 10 * some architectures. Use get_unaligned for unaligned data. 11 * 12 * Francois-Rene Rideau <fare (at) tunes.org> 19970707 13 * gathered all the good ideas from all asm-foo/byteorder.h into one file, 14 * cleaned them up. 15 * I hope it is compliant with non-GCC compilers. 16 * I decided to put __BYTEORDER_HAS_U64__ in byteorder.h, 17 * because I wasn't sure it would be ok to put it in types.h 18 * Upgraded it to 2.1.43 19 * Francois-Rene Rideau <fare (at) tunes.org> 19971012 20 * Upgraded it to 2.1.57 21 * to please Linus T., replaced huge #ifdef's between little/big endian 22 * by nestedly #include'd files. 23 * Francois-Rene Rideau <fare (at) tunes.org> 19971205 24 * Made it to 2.1.71; now a facelift: 25 * Put files under include/linux/byteorder/ 26 * Split swab from generic support. 27 * 28 * TODO: 29 * = Regular kernel maintainers could also replace all these manual 30 * byteswap macros that remain, disseminated among drivers, 31 * after some grep or the sources... 32 * = Linus might want to rename all these macros and files to fit his taste, 33 * to fit his personal naming scheme. 34 * = it seems that a few drivers would also appreciate 35 * nybble swapping support... 36 * = every architecture could add their byteswap macro in asm/byteorder.h 37 * see how some architectures already do (i386, alpha, ppc, etc) 38 * = cpu_to_beXX and beXX_to_cpu might some day need to be well 39 * distinguished throughout the kernel. This is not the case currently, 40 * since little endian, big endian, and pdp endian machines needn't it. 41 * But this might be the case for, say, a port of Linux to 20/21 bit 42 * architectures (and F21 Linux addict around?). 43 */ 44 45 /* 46 * The following macros are to be defined by <asm/byteorder.h>: 47 * 48 * Conversion of long and short int between network and host format 49 * ntohl(__u32 x) 50 * ntohs(__u16 x) 51 * htonl(__u32 x) 52 * htons(__u16 x) 53 * It seems that some programs (which? where? or perhaps a standard? POSIX?) 54 * might like the above to be functions, not macros (why?). 55 * if that's true, then detect them, and take measures. 56 * Anyway, the measure is: define only ___ntohl as a macro instead, 57 * and in a separate file, have 58 * unsigned long inline ntohl(x){return ___ntohl(x);} 59 * 60 * The same for constant arguments 61 * __constant_ntohl(__u32 x) 62 * __constant_ntohs(__u16 x) 63 * __constant_htonl(__u32 x) 64 * __constant_htons(__u16 x) 65 * 66 * Conversion of XX-bit integers (16- 32- or 64-) 67 * between native CPU format and little/big endian format 68 * 64-bit stuff only defined for proper architectures 69 * cpu_to_[bl]eXX(__uXX x) 70 * [bl]eXX_to_cpu(__uXX x) 71 * 72 * The same, but takes a pointer to the value to convert 73 * cpu_to_[bl]eXXp(__uXX x) 74 * [bl]eXX_to_cpup(__uXX x) 75 * 76 * The same, but change in situ 77 * cpu_to_[bl]eXXs(__uXX x) 78 * [bl]eXX_to_cpus(__uXX x) 79 * 80 * See asm-foo/byteorder.h for examples of how to provide 81 * architecture-optimized versions 82 * 83 */ 84 85 86 #if defined(__KERNEL__) 87 /* 88 * inside the kernel, we can use nicknames; 89 * outside of it, we must avoid POSIX namespace pollution... 90 */ 91 #define cpu_to_le64 __cpu_to_le64 92 #define le64_to_cpu __le64_to_cpu 93 #define cpu_to_le32 __cpu_to_le32 94 #define le32_to_cpu __le32_to_cpu 95 #define cpu_to_le16 __cpu_to_le16 96 #define le16_to_cpu __le16_to_cpu 97 #define cpu_to_be64 __cpu_to_be64 98 #define be64_to_cpu __be64_to_cpu 99 #define cpu_to_be32 __cpu_to_be32 100 #define be32_to_cpu __be32_to_cpu 101 #define cpu_to_be16 __cpu_to_be16 102 #define be16_to_cpu __be16_to_cpu 103 #define cpu_to_le64p __cpu_to_le64p 104 #define le64_to_cpup __le64_to_cpup 105 #define cpu_to_le32p __cpu_to_le32p 106 #define le32_to_cpup __le32_to_cpup 107 #define cpu_to_le16p __cpu_to_le16p 108 #define le16_to_cpup __le16_to_cpup 109 #define cpu_to_be64p __cpu_to_be64p 110 #define be64_to_cpup __be64_to_cpup 111 #define cpu_to_be32p __cpu_to_be32p 112 #define be32_to_cpup __be32_to_cpup 113 #define cpu_to_be16p __cpu_to_be16p 114 #define be16_to_cpup __be16_to_cpup 115 #define cpu_to_le64s __cpu_to_le64s 116 #define le64_to_cpus __le64_to_cpus 117 #define cpu_to_le32s __cpu_to_le32s 118 #define le32_to_cpus __le32_to_cpus 119 #define cpu_to_le16s __cpu_to_le16s 120 #define le16_to_cpus __le16_to_cpus 121 #define cpu_to_be64s __cpu_to_be64s 122 #define be64_to_cpus __be64_to_cpus 123 #define cpu_to_be32s __cpu_to_be32s 124 #define be32_to_cpus __be32_to_cpus 125 #define cpu_to_be16s __cpu_to_be16s 126 #define be16_to_cpus __be16_to_cpus 127 #endif 128 129 130 #if defined(__KERNEL__) 131 /* 132 * Handle ntohl and suches. These have various compatibility 133 * issues - like we want to give the prototype even though we 134 * also have a macro for them in case some strange program 135 * wants to take the address of the thing or something.. 136 * 137 * Note that these used to return a "long" in libc5, even though 138 * long is often 64-bit these days.. Thus the casts. 139 * 140 * They have to be macros in order to do the constant folding 141 * correctly - if the argument passed into a inline function 142 * it is no longer constant according to gcc.. 143 */ 144 145 #undef ntohl 146 #undef ntohs 147 #undef htonl 148 #undef htons 149 150 /* 151 * Do the prototypes. Somebody might want to take the 152 * address or some such sick thing.. 153 */ 154 extern __u32 ntohl(__be32); 155 extern __be32 htonl(__u32); 156 extern __u16 ntohs(__be16); 157 extern __be16 htons(__u16); 158 159 #if defined(__GNUC__) && defined(__OPTIMIZE__) 160 161 #define ___htonl(x) __cpu_to_be32(x) 162 #define ___htons(x) __cpu_to_be16(x) 163 #define ___ntohl(x) __be32_to_cpu(x) 164 #define ___ntohs(x) __be16_to_cpu(x) 165 166 #define htonl(x) ___htonl(x) 167 #define ntohl(x) ___ntohl(x) 168 #define htons(x) ___htons(x) 169 #define ntohs(x) ___ntohs(x) 170 171 #endif /* OPTIMIZE */ 172 173 #endif /* KERNEL */ 174 175 176 #endif /* _LINUX_BYTEORDER_GENERIC_H */ 177
