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__
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 */