| //===-- wrappers_c_checks.h -------------------------------------*- C++ -*-===// |
| // |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| // See https://llvm.org/LICENSE.txt for license information. |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #ifndef SCUDO_CHECKS_H_ |
| #define SCUDO_CHECKS_H_ |
| |
| #include "common.h" |
| |
| #include <errno.h> |
| |
| #ifndef __has_builtin |
| #define __has_builtin(X) 0 |
| #endif |
| |
| namespace scudo { |
| |
| // A common errno setting logic shared by almost all Scudo C wrappers. |
| inline void *setErrnoOnNull(void *Ptr) { |
| if (UNLIKELY(!Ptr)) |
| errno = ENOMEM; |
| return Ptr; |
| } |
| |
| // Checks return true on failure. |
| |
| // Checks aligned_alloc() parameters, verifies that the alignment is a power of |
| // two and that the size is a multiple of alignment. |
| inline bool checkAlignedAllocAlignmentAndSize(uptr Alignment, uptr Size) { |
| return Alignment == 0 || !isPowerOfTwo(Alignment) || |
| !isAligned(Size, Alignment); |
| } |
| |
| // Checks posix_memalign() parameters, verifies that alignment is a power of two |
| // and a multiple of sizeof(void *). |
| inline bool checkPosixMemalignAlignment(uptr Alignment) { |
| return Alignment == 0 || !isPowerOfTwo(Alignment) || |
| !isAligned(Alignment, sizeof(void *)); |
| } |
| |
| // Returns true if calloc(Size, N) overflows on Size*N calculation. Use a |
| // builtin supported by recent clang & GCC if it exists, otherwise fallback to a |
| // costly division. |
| inline bool checkForCallocOverflow(uptr Size, uptr N, uptr *Product) { |
| #if __has_builtin(__builtin_umull_overflow) |
| return __builtin_umull_overflow(Size, N, Product); |
| #else |
| *Product = Size * N; |
| if (!Size) |
| return false; |
| return (*Product / Size) != N; |
| #endif |
| } |
| |
| // Returns true if the size passed to pvalloc overflows when rounded to the next |
| // multiple of PageSize. |
| inline bool checkForPvallocOverflow(uptr Size, uptr PageSize) { |
| return roundUpTo(Size, PageSize) < Size; |
| } |
| |
| } // namespace scudo |
| |
| #endif // SCUDO_CHECKS_H_ |