//===- Errno.cpp - errno support --------------------------------*- C++ -*-===// // // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. // See https://llvm.org/LICENSE.txt for license information. // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception // //===----------------------------------------------------------------------===// // // This file implements the errno wrappers. // //===----------------------------------------------------------------------===// #include "llvm/Support/Errno.h" #include "llvm/Config/config.h" #include "llvm/Support/raw_ostream.h" #include <string.h> #if HAVE_ERRNO_H #include <errno.h> #endif //===----------------------------------------------------------------------===// //=== WARNING: Implementation here must contain only TRULY operating system //=== independent code. //===----------------------------------------------------------------------===// namespace llvm { namespace sys { #if HAVE_ERRNO_H std::string StrError() { return StrError(errno); } #endif // HAVE_ERRNO_H std::string StrError(int errnum) { std::string str; if (errnum == 0) return str; #if defined(HAVE_STRERROR_R) || HAVE_DECL_STRERROR_S const int MaxErrStrLen = 2000; char buffer[MaxErrStrLen]; buffer[0] = '\0'; #endif #ifdef HAVE_STRERROR_R // strerror_r is thread-safe. #if defined(__GLIBC__) && defined(_GNU_SOURCE) // glibc defines its own incompatible version of strerror_r // which may not use the buffer supplied. str = strerror_r(errnum, buffer, MaxErrStrLen - 1); #else strerror_r(errnum, buffer, MaxErrStrLen - 1); str = buffer; #endif #elif HAVE_DECL_STRERROR_S // "Windows Secure API" strerror_s(buffer, MaxErrStrLen - 1, errnum); str = buffer; #elif defined(HAVE_STRERROR) // Copy the thread un-safe result of strerror into // the buffer as fast as possible to minimize impact // of collision of strerror in multiple threads. str = strerror(errnum); #else // Strange that this system doesn't even have strerror // but, oh well, just use a generic message raw_string_ostream stream(str); stream << "Error #" << errnum; stream.flush(); #endif return str; } } // namespace sys } // namespace llvm |