xref: /freebsd/contrib/llvm-project/llvm/include/llvm/Support/Errno.h (revision 0b57cec536236d46e3dba9bd041533462f33dbb7)
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
47