1 //===- llvm/Support/Errno.h - Portable+convenient errno handling -*- C++ -*-===// 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 // This file declares some portable and convenient functions to deal with errno. 10 // 11 //===----------------------------------------------------------------------===// 12 13 #ifndef LLVM_SUPPORT_ERRNO_H 14 #define LLVM_SUPPORT_ERRNO_H 15 16 #include <cerrno> 17 #include <string> 18 19 namespace llvm { 20 namespace sys { 21 22 /// Returns a string representation of the errno value, using whatever 23 /// thread-safe variant of strerror() is available. Be sure to call this 24 /// immediately after the function that set errno, or errno may have been 25 /// overwritten by an intervening call. 26 std::string StrError(); 27 28 /// Like the no-argument version above, but uses \p errnum instead of errno. 29 std::string StrError(int errnum); 30 31 template <typename FailT, typename Fun, typename... Args> decltype(auto)32inline decltype(auto) RetryAfterSignal(const FailT &Fail, const Fun &F, 33 const Args &... As) { 34 decltype(F(As...)) Res; 35 do { 36 errno = 0; 37 Res = F(As...); 38 } while (Res == Fail && errno == EINTR); 39 return Res; 40 } 41 42 } // namespace sys 43 } // namespace llvm 44 45 #endif // LLVM_SUPPORT_ERRNO_H 46