last_error.h

 
#pragma once
 
#include "common.h"
 
#include <string>

 
namespace ghassanpl
{
 
    struct last_windows_error_t
    {
        uint32_t value{};
        std::string formatted;
    };
 
    namespace detail
    {
#if !defined(DOXYGEN)
        extern "C" __declspec(dllimport) win::DWORD __stdcall FormatMessageA(win::DWORD dwFlags, const void* lpSource, win::DWORD dwMessageId, win::DWORD dwLanguageId, char* lpBuffer, win::DWORD nSize, va_list * Arguments);
        extern "C" __declspec(dllimport) win::HANDLE __stdcall LocalFree(win::HANDLE hMem);
#endif
    }
 
    [[nodiscard]] inline last_windows_error_t get_last_windows_error()
    {
        const auto le = win::GetLastError(); 
 
        last_windows_error_t result{};
        result.value = le;
        if (le != 0)
        {
            char* messageBuffer = nullptr;
            size_t size = detail::FormatMessageA(0x00000100 | 0x00001000 | 0x00000200 | 0xFF, nullptr, le, 0, (char*)&messageBuffer, 0, nullptr);
            result.formatted = std::string{ messageBuffer, size };
            detail::LocalFree(messageBuffer);
        }
        return result;
    }
}