LLVM  9.0.0svn
Errno.h
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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
This class represents lattice values for constants.
Definition: AllocatorList.h:23
F(f)
std::string StrError()
Returns a string representation of the errno value, using whatever thread-safe variant of strerror() ...
Definition: Errno.cpp:31
#define Fail
auto RetryAfterSignal(const FailT &Fail, const Fun &F, const Args &... As) -> decltype(F(As...))
Definition: Errno.h:33
constexpr char Args[]
Key for Kernel::Metadata::mArgs.