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