| blob | 5fde6f4d6c1e3692b0abd52945e48721f428410d |
1 #ifndef _LINUX_BYTEORDER_GENERIC_H
2 #define _LINUX_BYTEORDER_GENERIC_H
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 */
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 */
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
126 #if defined(__KERNEL__)
127 /*
128 * Handle ntohl and suches. These have various compatibility
129 * issues - like we want to give the prototype even though we
130 * also have a macro for them in case some strange program
131 * wants to take the address of the thing or something..
132 *
133 * Note that these used to return a "long" in libc5, even though
134 * long is often 64-bit these days.. Thus the casts.
135 *
136 * They have to be macros in order to do the constant folding
137 * correctly - if the argument passed into a inline function
138 * it is no longer constant according to gcc..
139 */
141 #undef ntohl
142 #undef ntohs
143 #undef htonl
144 #undef htons
146 /*
147 * Do the prototypes. Somebody might want to take the
148 * address or some such sick thing..
149 */
155 #if defined(__GNUC__) && (__GNUC__ >= 2) && defined(__OPTIMIZE__)
157 #define ___htonl(x) __cpu_to_be32(x)
158 #define ___htons(x) __cpu_to_be16(x)
159 #define ___ntohl(x) __be32_to_cpu(x)
160 #define ___ntohs(x) __be16_to_cpu(x)
162 #define htonl(x) ___htonl(x)
163 #define ntohl(x) ___ntohl(x)
164 #define htons(x) ___htons(x)
165 #define ntohs(x) ___ntohs(x)