diff options
| author | Kurt Roeckx <kurt@roeckx.be> | 2020-07-11 17:17:09 +0200 |
|---|---|---|
| committer | Kurt Roeckx <kurt@roeckx.be> | 2020-10-14 09:51:56 +0200 |
| commit | 47690cd4ceb3a1cfdf097d575cb0d3cf9c6dac13 (patch) | |
| tree | 8aca5a0653d7dc67c2210fa1fc3503d67df3d331 /include/internal/endian.h | |
| parent | 8e596a93bc266259f1ef0d56601e58bbfe18317a (diff) | |
Use __BYTE_ORDER__ to test the endianness when available
Reviewed-by: Paul Dale <paul.dale@oracle.com>
GH: #13085
Diffstat (limited to 'include/internal/endian.h')
| -rw-r--r-- | include/internal/endian.h | 34 |
1 files changed, 31 insertions, 3 deletions
diff --git a/include/internal/endian.h b/include/internal/endian.h index f581c14b24..b4e486da3a 100644 --- a/include/internal/endian.h +++ b/include/internal/endian.h @@ -10,13 +10,41 @@ #ifndef OSSL_INTERNAL_ENDIAN_H # define OSSL_INTERNAL_ENDIAN_H -# define DECLARE_IS_ENDIAN \ +/* + * IS_LITTLE_ENDIAN and IS_BIG_ENDIAN can be used to detect the endiannes + * at compile time. To use it, DECLARE_IS_ENDIAN must be used to declare + * a variable. + * + * L_ENDIAN and B_ENDIAN can be used at preprocessor time. They can be set + * in the configarion using the lib_cppflags variable. If neither is + * set, it will fall back to code works with either endianness. + */ + +# if defined(__BYTE_ORDER__) && defined(__ORDER_LITTLE_ENDIAN__) +# define DECLARE_IS_ENDIAN const int ossl_is_little_endian = __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__ +# define IS_LITTLE_ENDIAN (ossl_is_little_endian) +# define IS_BIG_ENDIAN (!ossl_is_little_endian) +# if defined(L_ENDIAN) && (__BYTE_ORDER__ != __ORDER_LITTLE_ENDIAN__) +# error "L_ENDIAN defined on a big endian machine" +# endif +# if defined(B_ENDIAN) && (__BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__) +# error "B_ENDIAN defined on a little endian machine" +# endif +# if !defined(L_ENDIAN) && (__BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__) +# define L_ENDIAN +# endif +# if !defined(B_ENDIAN) && (__BYTE_ORDER__ != __ORDER_LITTLE_ENDIAN__) +# define B_ENDIAN +# endif +# else +# define DECLARE_IS_ENDIAN \ const union { \ long one; \ char little; \ } ossl_is_endian = { 1 } -# define IS_LITTLE_ENDIAN (ossl_is_endian.little != 0) -# define IS_BIG_ENDIAN (ossl_is_endian.little == 0) +# define IS_LITTLE_ENDIAN (ossl_is_endian.little != 0) +# define IS_BIG_ENDIAN (ossl_is_endian.little == 0) +# endif #endif |