diff options
| -rw-r--r-- | include/compat.h | 44 |
1 files changed, 27 insertions, 17 deletions
diff --git a/include/compat.h b/include/compat.h index b2bb054..ee47ef9 100644 --- a/include/compat.h +++ b/include/compat.h @@ -9,26 +9,36 @@ #include "sqfs/predef.h" -#if defined(__GNUC__) || defined(__clang__) -# if defined(__GNUC__) && __GNUC__ < 5 -# if SIZEOF_SIZE_T <= SIZEOF_INT -# define SZ_ADD_OV __builtin_uadd_overflow -# define SZ_MUL_OV __builtin_umul_overflow -# elif SIZEOF_SIZE_T == SIZEOF_LONG -# define SZ_ADD_OV __builtin_uaddl_overflow -# define SZ_MUL_OV __builtin_umull_overflow -# elif SIZEOF_SIZE_T == SIZEOF_LONG_LONG -# define SZ_ADD_OV __builtin_uaddll_overflow -# define SZ_MUL_OV __builtin_umulll_overflow -# else -# error Cannot determine maximum value of size_t -# endif +#if defined(__GNUC__) && __GNUC__ >= 5 +# define SZ_ADD_OV __builtin_add_overflow +# define SZ_MUL_OV __builtin_mul_overflow +#elif defined(__clang__) && defined(__GNUC__) && __GNUC__ < 5 +# if SIZEOF_SIZE_T <= SIZEOF_INT +# define SZ_ADD_OV __builtin_uadd_overflow +# define SZ_MUL_OV __builtin_umul_overflow +# elif SIZEOF_SIZE_T == SIZEOF_LONG +# define SZ_ADD_OV __builtin_uaddl_overflow +# define SZ_MUL_OV __builtin_umull_overflow +# elif SIZEOF_SIZE_T == SIZEOF_LONG_LONG +# define SZ_ADD_OV __builtin_uaddll_overflow +# define SZ_MUL_OV __builtin_umulll_overflow # else -# define SZ_ADD_OV __builtin_add_overflow -# define SZ_MUL_OV __builtin_mul_overflow +# error Cannot determine maximum value of size_t # endif #else -# error I do not know how to trap integer overflows with this compiler +static inline int _sz_add_overflow(size_t a, size_t b, size_t *res) +{ + *res = a + b; + return (*res < a) ? 1 : 0; +} + +static inline int _sz_mul_overflow(size_t a, size_t b, size_t *res) +{ + *res = a * b; + return (b > 0 && (a > SIZE_MAX / b)) ? 1 : 0; +} +# define SZ_ADD_OV _sz_add_overflow +# define SZ_MUL_OV _sz_mul_overflow #endif #if defined(_WIN32) || defined(__WINDOWS__) |