xref: /onnv-gate/usr/src/lib/libntfs/common/include/ntfs/endians.h (revision 9663:ace9a2ac3683)
1 /*
2  * endians.h - Definitions related to handling of byte ordering. Part of the
3  *	       Linux-NTFS project.
4  *
5  * Copyright (c) 2000-2005 Anton Altaparmakov
6  * Copyright (c)      2007 Yura Pakhuchiy
7  *
8  * This program/include file is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU General Public License as published
10  * by the Free Software Foundation; either version 2 of the License, or
11  * (at your option) any later version.
12  *
13  * This program/include file is distributed in the hope that it will be
14  * useful, but WITHOUT ANY WARRANTY; without even the implied warranty
15  * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program (in the main directory of the Linux-NTFS
20  * distribution in the file COPYING); if not, write to the Free Software
21  * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
22  */
23 
24 #ifndef _NTFS_ENDIANS_H
25 #define _NTFS_ENDIANS_H
26 
27 #ifdef HAVE_CONFIG_H
28 #include "config.h"
29 #endif
30 
31 /*
32  * Notes:
33  *	We define the conversion functions including typecasts since the
34  * defaults don't necessarily perform appropriate typecasts.
35  *	Also, using our own functions means that we can change them if it
36  * turns out that we do need to use the unaligned access macros on
37  * architectures requiring aligned memory accesses...
38  */
39 
40 #ifdef HAVE_ENDIAN_H
41 #include <endian.h>
42 #endif
43 #ifdef HAVE_SYS_ENDIAN_H
44 #include <sys/endian.h>
45 #endif
46 #ifdef HAVE_MACHINE_ENDIAN_H
47 #include <machine/endian.h>
48 #endif
49 #ifdef HAVE_SYS_BYTEORDER_H
50 #include <sys/byteorder.h>
51 #endif
52 #ifdef HAVE_SYS_PARAM_H
53 #include <sys/param.h>
54 #endif
55 
56 #ifndef __BYTE_ORDER
57 #	if defined(_BYTE_ORDER)
58 #		define __BYTE_ORDER _BYTE_ORDER
59 #		define __LITTLE_ENDIAN _LITTLE_ENDIAN
60 #		define __BIG_ENDIAN _BIG_ENDIAN
61 #	elif defined(BYTE_ORDER)
62 #		define __BYTE_ORDER BYTE_ORDER
63 #		define __LITTLE_ENDIAN LITTLE_ENDIAN
64 #		define __BIG_ENDIAN BIG_ENDIAN
65 #	elif defined(__BYTE_ORDER__)
66 #		define __BYTE_ORDER __BYTE_ORDER__
67 #		define __LITTLE_ENDIAN __LITTLE_ENDIAN__
68 #		define __BIG_ENDIAN __BIG_ENDIAN__
69 #	elif (defined(_LITTLE_ENDIAN) && !defined(_BIG_ENDIAN)) || \
70 			defined(WORDS_LITTLEENDIAN)
71 #		define __BYTE_ORDER 1
72 #		define __LITTLE_ENDIAN 1
73 #		define __BIG_ENDIAN 0
74 #	elif (!defined(_LITTLE_ENDIAN) && defined(_BIG_ENDIAN)) || \
75 			defined(WORDS_BIGENDIAN)
76 #		define __BYTE_ORDER 0
77 #		define __LITTLE_ENDIAN 1
78 #		define __BIG_ENDIAN 0
79 #	else
80 #		error "__BYTE_ORDER is not defined."
81 #	endif
82 #endif
83 
84 #define __ntfs_bswap_constant_16(x)		\
85 	  (u16)((((u16)(x) & 0xff00) >> 8) |	\
86 		(((u16)(x) & 0x00ff) << 8))
87 
88 #define __ntfs_bswap_constant_32(x)			\
89 	  (u32)((((u32)(x) & 0xff000000u) >> 24) |	\
90 		(((u32)(x) & 0x00ff0000u) >>  8) |	\
91 		(((u32)(x) & 0x0000ff00u) <<  8) |	\
92 		(((u32)(x) & 0x000000ffu) << 24))
93 
94 #define __ntfs_bswap_constant_64(x)				\
95 	  (u64)((((u64)(x) & 0xff00000000000000ull) >> 56) |	\
96 		(((u64)(x) & 0x00ff000000000000ull) >> 40) |	\
97 		(((u64)(x) & 0x0000ff0000000000ull) >> 24) |	\
98 		(((u64)(x) & 0x000000ff00000000ull) >>  8) |	\
99 		(((u64)(x) & 0x00000000ff000000ull) <<  8) |	\
100 		(((u64)(x) & 0x0000000000ff0000ull) << 24) |	\
101 		(((u64)(x) & 0x000000000000ff00ull) << 40) |	\
102 		(((u64)(x) & 0x00000000000000ffull) << 56))
103 
104 #ifdef HAVE_BYTESWAP_H
105 #	include <byteswap.h>
106 #else
107 #	define bswap_16(x) __ntfs_bswap_constant_16(x)
108 #	define bswap_32(x) __ntfs_bswap_constant_32(x)
109 #	define bswap_64(x) __ntfs_bswap_constant_64(x)
110 #endif
111 
112 #if defined(__LITTLE_ENDIAN) && (__BYTE_ORDER == __LITTLE_ENDIAN)
113 
114 #define __le16_to_cpu(x) ((__force u16)(x))
115 #define __le32_to_cpu(x) ((__force u32)(x))
116 #define __le64_to_cpu(x) ((__force u64)(x))
117 
118 #define __cpu_to_le16(x) ((__force le16)(x))
119 #define __cpu_to_le32(x) ((__force le32)(x))
120 #define __cpu_to_le64(x) ((__force le64)(x))
121 
122 #define __constant_le16_to_cpu(x) ((__force u16)(x))
123 #define __constant_le32_to_cpu(x) ((__force u32)(x))
124 #define __constant_le64_to_cpu(x) ((__force u64)(x))
125 
126 #define __constant_cpu_to_le16(x) ((__force le16)(x))
127 #define __constant_cpu_to_le32(x) ((__force le32)(x))
128 #define __constant_cpu_to_le64(x) ((__force le64)(x))
129 
130 #elif defined(__BIG_ENDIAN) && (__BYTE_ORDER == __BIG_ENDIAN)
131 
132 #define __le16_to_cpu(x) bswap_16((__force u16)(x))
133 #define __le32_to_cpu(x) bswap_32((__force u16)(x))
134 #define __le64_to_cpu(x) bswap_64((__force u16)(x))
135 
136 #define __cpu_to_le16(x) (__force le16)bswap_16((__force u16)(x))
137 #define __cpu_to_le32(x) (__force le32)bswap_32((__force u32)(x))
138 #define __cpu_to_le64(x) (__force le64)bswap_64((__force u64)(x))
139 
140 #define __constant_le16_to_cpu(x) __ntfs_bswap_constant_16((__force u16)(x))
141 #define __constant_le32_to_cpu(x) __ntfs_bswap_constant_32((__force u32)(x))
142 #define __constant_le64_to_cpu(x) __ntfs_bswap_constant_64((__force u64)(x))
143 
144 #define __constant_cpu_to_le16(x) \
145 	(__force le16)__ntfs_bswap_constant_16((__force u16)(x))
146 #define __constant_cpu_to_le32(x) \
147 	(__force le32)__ntfs_bswap_constant_32((__force u32)(x))
148 #define __constant_cpu_to_le64(x) \
149 	(__force le64)__ntfs_bswap_constant_64((__force u64)(x))
150 
151 #else
152 
153 #error "You must define __BYTE_ORDER to be __LITTLE_ENDIAN or __BIG_ENDIAN."
154 
155 #endif
156 
157 /* Unsigned from LE to CPU conversion. */
158 
159 #define le16_to_cpu(x)		(u16)__le16_to_cpu((le16)(x))
160 #define le32_to_cpu(x)		(u32)__le32_to_cpu((le32)(x))
161 #define le64_to_cpu(x)		(u64)__le64_to_cpu((le64)(x))
162 
163 #define le16_to_cpup(x)		(u16)__le16_to_cpu(*(const le16*)(x))
164 #define le32_to_cpup(x)		(u32)__le32_to_cpu(*(const le32*)(x))
165 #define le64_to_cpup(x)		(u64)__le64_to_cpu(*(const le64*)(x))
166 
167 /* Signed from LE to CPU conversion. */
168 
169 #define sle16_to_cpu(x)		(s16)__le16_to_cpu((sle16)(x))
170 #define sle32_to_cpu(x)		(s32)__le32_to_cpu((sle32)(x))
171 #define sle64_to_cpu(x)		(s64)__le64_to_cpu((sle64)(x))
172 
173 #define sle16_to_cpup(x)	(s16)__le16_to_cpu(*(const sle16*)(x))
174 #define sle32_to_cpup(x)	(s32)__le32_to_cpu(*(const sle32*)(x))
175 #define sle64_to_cpup(x)	(s64)__le64_to_cpu(*(const sle64*)(x))
176 
177 /* Unsigned from CPU to LE conversion. */
178 
179 #define cpu_to_le16(x)		(le16)__cpu_to_le16((u16)(x))
180 #define cpu_to_le32(x)		(le32)__cpu_to_le32((u32)(x))
181 #define cpu_to_le64(x)		(le64)__cpu_to_le64((u64)(x))
182 
183 #define cpu_to_le16p(x)		(le16)__cpu_to_le16(*(const u16*)(x))
184 #define cpu_to_le32p(x)		(le32)__cpu_to_le32(*(const u32*)(x))
185 #define cpu_to_le64p(x)		(le64)__cpu_to_le64(*(const u64*)(x))
186 
187 /* Signed from CPU to LE conversion. */
188 
189 #define cpu_to_sle16(x)		(__force sle16)__cpu_to_le16((s16)(x))
190 #define cpu_to_sle32(x)		(__force sle32)__cpu_to_le32((s32)(x))
191 #define cpu_to_sle64(x)		(__force sle64)__cpu_to_le64((s64)(x))
192 
193 #define cpu_to_sle16p(x)	(__force sle16)__cpu_to_le16(*(const s16*)(x))
194 #define cpu_to_sle32p(x)	(__force sle32)__cpu_to_le32(*(const s32*)(x))
195 #define cpu_to_sle64p(x)	(__force sle64)__cpu_to_le64(*(const s64*)(x))
196 
197 /* Constant endianness conversion defines. */
198 
199 #define const_le16_to_cpu(x)	(u16)__constant_le16_to_cpu((le16)(x))
200 #define const_le32_to_cpu(x)	(u32)__constant_le32_to_cpu((le32)(x))
201 #define const_le64_to_cpu(x)	(u64)__constant_le64_to_cpu((le64)(x))
202 
203 #define const_cpu_to_le16(x)	(le16)__constant_cpu_to_le16((u16)(x))
204 #define const_cpu_to_le32(x)	(le32)__constant_cpu_to_le32((u32)(x))
205 #define const_cpu_to_le64(x)	(le64)__constant_cpu_to_le64((u64)(x))
206 
207 #ifdef __CHECKER__
ntfs_endian_self_test(void)208 static void ntfs_endian_self_test(void)
209 {
210 	/* Should not generate warnings. */
211 	(le16)cpu_to_le16((u16)1);
212 	(le32)cpu_to_le32((u32)1);
213 	(le64)cpu_to_le64((u64)1);
214 	(sle16)cpu_to_sle16((s16)1);
215 	(sle32)cpu_to_sle32((s32)1);
216 	(sle64)cpu_to_sle64((s64)1);
217 	(u16)le16_to_cpu((__force le16)1);
218 	(u32)le32_to_cpu((__force le32)1);
219 	(u64)le64_to_cpu((__force le64)1);
220 	(s16)sle16_to_cpu((__force sle16)1);
221 	(s32)sle32_to_cpu((__force sle32)1);
222 	(s64)sle64_to_cpu((__force sle64)1);
223 	(le16)const_cpu_to_le16((u16)1);
224 	(le32)const_cpu_to_le32((u32)1);
225 	(le64)const_cpu_to_le64((u64)1);
226 	(u16)const_le16_to_cpu((__force le16)1);
227 	(u32)const_le32_to_cpu((__force le32)1);
228 	(u64)const_le64_to_cpu((__force le64)1);
229 
230 	/*
231 	 * TODO: Need some how to test that warnings are actually generated,
232 	 * but without flooding output with them and vice-versa print warning
233 	 * in case if some one warning is not triggered, but should.  (Yura)
234 	 *
235 	 * I think it can only be done in  a ./configure like script / shell
236 	 * script that will compile known good  and known bad code and pipe the
237 	 * output from sparse to a file, then  grep the file for the wanted
238 	 * warnings/lack thereof and then it would  say "Tests: PASS " or
239 	 * "Tests: FAILED" or whatever.  And you can then  hook that into a
240 	 * "make test" make target or similar so it is only  done when one
241 	 * wants to do it...  (Anton)
242 	 *
243 	 * Also we can look on sparse self test script.  (Yura)
244 	 */
245 }
246 #endif
247 
248 #endif /* defined _NTFS_ENDIANS_H */
249