diff options
Diffstat (limited to 'lib/compiler.h')
| -rw-r--r-- | lib/compiler.h | 79 |
1 files changed, 76 insertions, 3 deletions
diff --git a/lib/compiler.h b/lib/compiler.h index 9ce91e3361..7c7f4ce294 100644 --- a/lib/compiler.h +++ b/lib/compiler.h @@ -173,6 +173,11 @@ extern "C" { #endif #endif +#ifdef container_of +#undef container_of +#endif + +#if !(defined(__cplusplus) || defined(test__cplusplus)) /* this variant of container_of() retains 'const' on pointers without needing * to be told to do so. The following will all work without warning: * @@ -191,9 +196,6 @@ extern "C" { * struct cont *x = container_of(cp, const struct cont, member); * struct cont *x = container_of(p, const struct cont, member); */ -#ifdef container_of -#undef container_of -#endif #define container_of(ptr, type, member) \ (__builtin_choose_expr( \ __builtin_types_compatible_p(typeof(&((type *)0)->member), \ @@ -209,6 +211,15 @@ extern "C" { offsetof(type, member)); \ }) \ )) +#else +/* current C++ compilers don't have the builtins used above; so this version + * of the macro doesn't do the const check. */ +#define container_of(ptr, type, member) \ + ({ \ + const typeof(((type *)0)->member) *__mptr = (ptr); \ + (type *)((char *)__mptr - offsetof(type, member)); \ + }) +#endif #define container_of_null(ptr, type, member) \ ({ \ @@ -218,6 +229,68 @@ extern "C" { #define array_size(ar) (sizeof(ar) / sizeof(ar[0])) +/* sigh. this is so ugly, it overflows and wraps to being nice again. + * + * printfrr() supports "%Ld" for <int64_t>, whatever that is typedef'd to. + * However, gcc & clang think that "%Ld" is <long long>, which doesn't quite + * match up since int64_t is <long> on a lot of 64-bit systems. + * + * If we have _FRR_ATTRIBUTE_PRINTFRR, we loaded a compiler plugin that + * replaces the whole format checking bits with a custom version that + * understands "%Ld" (along with "%pI4" and co.), so we don't need to do + * anything. + * + * If we don't have that attribute... we still want -Wformat to work. So, + * this is the "f*ck it" approach and we just redefine int64_t to always be + * <long long>. This should work until such a time that <long long> is + * something else (e.g. 128-bit integer)... let's just guard against that + * with the _Static_assert below and work with the world we have right now, + * where <long long> is always 64-bit. + */ + +/* these need to be included before any of the following, so we can + * "overwrite" things. + */ +#include <stdint.h> +#include <inttypes.h> + +#ifdef _FRR_ATTRIBUTE_PRINTFRR +#define PRINTFRR(a, b) __attribute__((printfrr(a, b))) + +#else /* !_FRR_ATTRIBUTE_PRINTFRR */ +#define PRINTFRR(a, b) __attribute__((format(printf, a, b))) + +/* these should be typedefs, but might also be #define */ +#ifdef uint64_t +#undef uint64_t +#endif +#ifdef int64_t +#undef int64_t +#endif + +/* can't overwrite the typedef, but we can replace int64_t with _int64_t */ +typedef unsigned long long _uint64_t; +#define uint64_t _uint64_t +typedef signed long long _int64_t; +#define int64_t _int64_t + +/* if this breaks, 128-bit machines may have entered reality (or <long long> + * is something weird) + */ +#if __STDC_VERSION__ >= 201112L +_Static_assert(sizeof(_uint64_t) == 8 && sizeof(_int64_t) == 8, + "nobody expects the spanish intquisition"); +#endif + +/* since we redefined int64_t, we also need to redefine PRI*64 */ +#undef PRIu64 +#undef PRId64 +#undef PRIx64 +#define PRIu64 "llu" +#define PRId64 "lld" +#define PRIx64 "llx" +#endif /* !_FRR_ATTRIBUTE_PRINTFRR */ + #ifdef __cplusplus } #endif |