// Copyright 2009 Dolphin Emulator Project
// Licensed under GPLv2+
// Refer to the license.txt file included.

// The code in GetErrorMessage can't handle some systems having the
// GNU version of strerror_r and other systems having the XSI version,
// so we undefine _GNU_SOURCE here in an attempt to always get the XSI version.
// We include cstring before all other headers in case cstring is included
// indirectly (without undefining _GNU_SOURCE) by some other header.
#ifdef _GNU_SOURCE
#undef _GNU_SOURCE
#include <cstring>
#define _GNU_SOURCE
#else
#include <cstring>
#endif

#include <cstddef>
#include <errno.h>

#include "Common/CommonFuncs.h"

#ifdef _WIN32
#include <windows.h>
#define strerror_r(err, buf, len) strerror_s(buf, len, err)
#endif

constexpr size_t BUFFER_SIZE = 256;

// Wrapper function to get last strerror(errno) string.
// This function might change the error code.
std::string LastStrerrorString()
{
  char error_message[BUFFER_SIZE];

  // We assume that the XSI-compliant version of strerror_r (returns int) is used
  // rather than the GNU version (returns char*). The returned value is stored to
  // an int variable to get a compile-time check that the return type is not char*.
  const int result = strerror_r(errno, error_message, BUFFER_SIZE);
  if (result != 0)
    return "";
  return std::string(error_message);
}

#ifdef _WIN32
// Wrapper function to get GetLastError() string.
// This function might change the error code.
std::string GetLastErrorString()
{
  char error_message[BUFFER_SIZE];

  FormatMessageA(FORMAT_MESSAGE_FROM_SYSTEM, nullptr, GetLastError(),
                 MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), error_message, BUFFER_SIZE, nullptr);
  return std::string(error_message);
}
#endif