llvm/Support/Errno.h

0001 //===- llvm/Support/Errno.h - Portable+convenient errno handling -*- C++ -*-===//
0002 //
0003 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
0004 // See https://llvm.org/LICENSE.txt for license information.
0005 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
0006 //
0007 //===----------------------------------------------------------------------===//
0008 //
0009 // This file declares some portable and convenient functions to deal with errno.
0010 //
0011 //===----------------------------------------------------------------------===//
0012
0013 #ifndef LLVM_SUPPORT_ERRNO_H
0014 #define LLVM_SUPPORT_ERRNO_H
0015
0016 #include <cerrno>
0017 #include <string>
0018
0019 namespace llvm {
0020 namespace sys {
0021
0022 /// Returns a string representation of the errno value, using whatever
0023 /// thread-safe variant of strerror() is available.  Be sure to call this
0024 /// immediately after the function that set errno, or errno may have been
0025 /// overwritten by an intervening call.
0026 std::string StrError();
0027
0028 /// Like the no-argument version above, but uses \p errnum instead of errno.
0029 std::string StrError(int errnum);
0030
0031 template <typename FailT, typename Fun, typename... Args>
0032 inline decltype(auto) RetryAfterSignal(const FailT &Fail, const Fun &F,
0033                                        const Args &... As) {
0034   decltype(F(As...)) Res;
0035   do {
0036     errno = 0;
0037     Res = F(As...);
0038   } while (Res == Fail && errno == EINTR);
0039   return Res;
0040 }
0041
0042 }  // namespace sys
0043 }  // namespace llvm
0044
0045 #endif // LLVM_SUPPORT_ERRNO_H