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1 /*
2 Copyright Rene Rivera 2013-2015
3 Distributed under the Boost Software License, Version 1.0.
4 (See accompanying file LICENSE_1_0.txt or copy at
5 http://www.boost.org/LICENSE_1_0.txt)
6 */
7 
8 #ifndef BOOST_PREDEF_ENDIAN_H
9 #define BOOST_PREDEF_ENDIAN_H
10 
11 #include <boost/predef/version_number.h>
12 #include <boost/predef/make.h>
13 #include <boost/predef/library/c/gnu.h>
14 #include <boost/predef/os/macos.h>
15 #include <boost/predef/os/bsd.h>
16 #include <boost/predef/platform/android.h>
17 
18 /* tag::reference[]
19 = `BOOST_ENDIAN_*`
20 
21 Detection of endian memory ordering. There are four defined macros
22 in this header that define the various generally possible endian
23 memory orderings:
24 
25 * `BOOST_ENDIAN_BIG_BYTE`, byte-swapped big-endian.
26 * `BOOST_ENDIAN_BIG_WORD`, word-swapped big-endian.
27 * `BOOST_ENDIAN_LITTLE_BYTE`, byte-swapped little-endian.
28 * `BOOST_ENDIAN_LITTLE_WORD`, word-swapped little-endian.
29 
30 The detection is conservative in that it only identifies endianness
31 that it knows for certain. In particular bi-endianness is not
32 indicated as is it not practically possible to determine the
33 endianness from anything but an operating system provided
34 header. And the currently known headers do not define that
35 programatic bi-endianness is available.
36 
37 This implementation is a compilation of various publicly available
38 information and acquired knowledge:
39 
40 . The indispensable documentation of "Pre-defined Compiler Macros"
41   http://sourceforge.net/p/predef/wiki/Endianness[Endianness].
42 . The various endian specifications available in the
43   http://wikipedia.org/[Wikipedia] computer architecture pages.
44 . Generally available searches for headers that define endianness.
45 */ // end::reference[]
46 
47 #define BOOST_ENDIAN_BIG_BYTE BOOST_VERSION_NUMBER_NOT_AVAILABLE
48 #define BOOST_ENDIAN_BIG_WORD BOOST_VERSION_NUMBER_NOT_AVAILABLE
49 #define BOOST_ENDIAN_LITTLE_BYTE BOOST_VERSION_NUMBER_NOT_AVAILABLE
50 #define BOOST_ENDIAN_LITTLE_WORD BOOST_VERSION_NUMBER_NOT_AVAILABLE
51 
52 /* GNU libc provides a header defining __BYTE_ORDER, or _BYTE_ORDER.
53  * And some OSs provide some for of endian header also.
54  */
55 #if !BOOST_ENDIAN_BIG_BYTE && !BOOST_ENDIAN_BIG_WORD && \
56     !BOOST_ENDIAN_LITTLE_BYTE && !BOOST_ENDIAN_LITTLE_WORD
57 #   if BOOST_LIB_C_GNU || BOOST_PLAT_ANDROID
58 #       include <endian.h>
59 #   else
60 #       if BOOST_OS_MACOS
61 #           include <machine/endian.h>
62 #       else
63 #           if BOOST_OS_BSD
64 #               if BOOST_OS_BSD_OPEN
65 #                   include <machine/endian.h>
66 #               else
67 #                   include <sys/endian.h>
68 #               endif
69 #           endif
70 #       endif
71 #   endif
72 #   if defined(__BYTE_ORDER)
73 #       if defined(__BIG_ENDIAN) && (__BYTE_ORDER == __BIG_ENDIAN)
74 #           undef BOOST_ENDIAN_BIG_BYTE
75 #           define BOOST_ENDIAN_BIG_BYTE BOOST_VERSION_NUMBER_AVAILABLE
76 #       endif
77 #       if defined(__LITTLE_ENDIAN) && (__BYTE_ORDER == __LITTLE_ENDIAN)
78 #           undef BOOST_ENDIAN_LITTLE_BYTE
79 #           define BOOST_ENDIAN_LITTLE_BYTE BOOST_VERSION_NUMBER_AVAILABLE
80 #       endif
81 #       if defined(__PDP_ENDIAN) && (__BYTE_ORDER == __PDP_ENDIAN)
82 #           undef BOOST_ENDIAN_LITTLE_WORD
83 #           define BOOST_ENDIAN_LITTLE_WORD BOOST_VERSION_NUMBER_AVAILABLE
84 #       endif
85 #   endif
86 #   if !defined(__BYTE_ORDER) && defined(_BYTE_ORDER)
87 #       if defined(_BIG_ENDIAN) && (_BYTE_ORDER == _BIG_ENDIAN)
88 #           undef BOOST_ENDIAN_BIG_BYTE
89 #           define BOOST_ENDIAN_BIG_BYTE BOOST_VERSION_NUMBER_AVAILABLE
90 #       endif
91 #       if defined(_LITTLE_ENDIAN) && (_BYTE_ORDER == _LITTLE_ENDIAN)
92 #           undef BOOST_ENDIAN_LITTLE_BYTE
93 #           define BOOST_ENDIAN_LITTLE_BYTE BOOST_VERSION_NUMBER_AVAILABLE
94 #       endif
95 #       if defined(_PDP_ENDIAN) && (_BYTE_ORDER == _PDP_ENDIAN)
96 #           undef BOOST_ENDIAN_LITTLE_WORD
97 #           define BOOST_ENDIAN_LITTLE_WORD BOOST_VERSION_NUMBER_AVAILABLE
98 #       endif
99 #   endif
100 #endif
101 
102 /* Built-in byte-swpped big-endian macros.
103  */
104 #if !BOOST_ENDIAN_BIG_BYTE && !BOOST_ENDIAN_BIG_WORD && \
105     !BOOST_ENDIAN_LITTLE_BYTE && !BOOST_ENDIAN_LITTLE_WORD
106 #   if (defined(__BIG_ENDIAN__) && !defined(__LITTLE_ENDIAN__)) || \
107        (defined(_BIG_ENDIAN) && !defined(_LITTLE_ENDIAN)) || \
108         defined(__ARMEB__) || \
109         defined(__THUMBEB__) || \
110         defined(__AARCH64EB__) || \
111         defined(_MIPSEB) || \
112         defined(__MIPSEB) || \
113         defined(__MIPSEB__)
114 #       undef BOOST_ENDIAN_BIG_BYTE
115 #       define BOOST_ENDIAN_BIG_BYTE BOOST_VERSION_NUMBER_AVAILABLE
116 #   endif
117 #endif
118 
119 /* Built-in byte-swpped little-endian macros.
120  */
121 #if !BOOST_ENDIAN_BIG_BYTE && !BOOST_ENDIAN_BIG_WORD && \
122     !BOOST_ENDIAN_LITTLE_BYTE && !BOOST_ENDIAN_LITTLE_WORD
123 #   if (defined(__LITTLE_ENDIAN__) && !defined(__BIG_ENDIAN__)) || \
124        (defined(_LITTLE_ENDIAN) && !defined(_BIG_ENDIAN)) || \
125         defined(__ARMEL__) || \
126         defined(__THUMBEL__) || \
127         defined(__AARCH64EL__) || \
128         defined(_MIPSEL) || \
129         defined(__MIPSEL) || \
130         defined(__MIPSEL__) || \
131         defined(__riscv)
132 #       undef BOOST_ENDIAN_LITTLE_BYTE
133 #       define BOOST_ENDIAN_LITTLE_BYTE BOOST_VERSION_NUMBER_AVAILABLE
134 #   endif
135 #endif
136 
137 /* Some architectures are strictly one endianess (as opposed
138  * the current common bi-endianess).
139  */
140 #if !BOOST_ENDIAN_BIG_BYTE && !BOOST_ENDIAN_BIG_WORD && \
141     !BOOST_ENDIAN_LITTLE_BYTE && !BOOST_ENDIAN_LITTLE_WORD
142 #   include <boost/predef/architecture.h>
143 #   if BOOST_ARCH_M68K || \
144         BOOST_ARCH_PARISC || \
145         BOOST_ARCH_SPARC || \
146         BOOST_ARCH_SYS370 || \
147         BOOST_ARCH_SYS390 || \
148         BOOST_ARCH_Z
149 #       undef BOOST_ENDIAN_BIG_BYTE
150 #       define BOOST_ENDIAN_BIG_BYTE BOOST_VERSION_NUMBER_AVAILABLE
151 #   endif
152 #   if BOOST_ARCH_IA64 || \
153         BOOST_ARCH_X86 || \
154         BOOST_ARCH_BLACKFIN
155 #       undef BOOST_ENDIAN_LITTLE_BYTE
156 #       define BOOST_ENDIAN_LITTLE_BYTE BOOST_VERSION_NUMBER_AVAILABLE
157 #   endif
158 #endif
159 
160 /* Windows on ARM, if not otherwise detected/specified, is always
161  * byte-swaped little-endian.
162  */
163 #if !BOOST_ENDIAN_BIG_BYTE && !BOOST_ENDIAN_BIG_WORD && \
164     !BOOST_ENDIAN_LITTLE_BYTE && !BOOST_ENDIAN_LITTLE_WORD
165 #   if BOOST_ARCH_ARM
166 #       include <boost/predef/os/windows.h>
167 #       if BOOST_OS_WINDOWS
168 #           undef BOOST_ENDIAN_LITTLE_BYTE
169 #           define BOOST_ENDIAN_LITTLE_BYTE BOOST_VERSION_NUMBER_AVAILABLE
170 #       endif
171 #   endif
172 #endif
173 
174 #if BOOST_ENDIAN_BIG_BYTE
175 #   define BOOST_ENDIAN_BIG_BYTE_AVAILABLE
176 #endif
177 #if BOOST_ENDIAN_BIG_WORD
178 #   define BOOST_ENDIAN_BIG_WORD_BYTE_AVAILABLE
179 #endif
180 #if BOOST_ENDIAN_LITTLE_BYTE
181 #   define BOOST_ENDIAN_LITTLE_BYTE_AVAILABLE
182 #endif
183 #if BOOST_ENDIAN_LITTLE_WORD
184 #   define BOOST_ENDIAN_LITTLE_WORD_BYTE_AVAILABLE
185 #endif
186 
187 #define BOOST_ENDIAN_BIG_BYTE_NAME "Byte-Swapped Big-Endian"
188 #define BOOST_ENDIAN_BIG_WORD_NAME "Word-Swapped Big-Endian"
189 #define BOOST_ENDIAN_LITTLE_BYTE_NAME "Byte-Swapped Little-Endian"
190 #define BOOST_ENDIAN_LITTLE_WORD_NAME "Word-Swapped Little-Endian"
191 
192 #endif
193 
194 #include <boost/predef/detail/test.h>
195 BOOST_PREDEF_DECLARE_TEST(BOOST_ENDIAN_BIG_BYTE,BOOST_ENDIAN_BIG_BYTE_NAME)
196 
197 #include <boost/predef/detail/test.h>
198 BOOST_PREDEF_DECLARE_TEST(BOOST_ENDIAN_BIG_WORD,BOOST_ENDIAN_BIG_WORD_NAME)
199 
200 #include <boost/predef/detail/test.h>
201 BOOST_PREDEF_DECLARE_TEST(BOOST_ENDIAN_LITTLE_BYTE,BOOST_ENDIAN_LITTLE_BYTE_NAME)
202 
203 #include <boost/predef/detail/test.h>
204 BOOST_PREDEF_DECLARE_TEST(BOOST_ENDIAN_LITTLE_WORD,BOOST_ENDIAN_LITTLE_WORD_NAME)
205