include/llvm/Support/Errno.h

   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 #include <type_traits>
  19
  20 namespace llvm {
  21 namespace sys {
  22
  23 /// Returns a string representation of the errno value, using whatever
  24 /// thread-safe variant of strerror() is available.  Be sure to call this
  25 /// immediately after the function that set errno, or errno may have been
  26 /// overwritten by an intervening call.
  27 std::string StrError();
  28
  29 /// Like the no-argument version above, but uses \p errnum instead of errno.
  30 std::string StrError(int errnum);
  31
  32 template <typename FailT, typename Fun, typename... Args>
  33 inline auto RetryAfterSignal(const FailT &Fail, const Fun &F,
  34                              const Args &... As) -> decltype(F(As...)) {
  35   decltype(F(As...)) Res;
  36   do {
  37     errno = 0;
  38     Res = F(As...);
  39   } while (Res == Fail && errno == EINTR);
  40   return Res;
  41 }
  42
  43 }  // namespace sys
  44 }  // namespace llvm
  45
  46 #endif  // LLVM_SYSTEM_ERRNO_H