1 //===-- Definition of the containerof macro -------------------------------===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 9 #ifndef LLVM_LIBC_MACROS_CONTAINEROF_MACRO_H 10 #define LLVM_LIBC_MACROS_CONTAINEROF_MACRO_H 11 12 #include "offsetof-macro.h" 13 14 #define __containerof(ptr, type, member) \ 15 ({ \ 16 const __typeof(((type *)0)->member) *__ptr = (ptr); \ 17 (type *)(void *)((const char *)__ptr - offsetof(type, member)); \ 18 }) 19 20 #endif // LLVM_LIBC_MACROS_CONTAINEROF_MACRO_H 21