Problem with compiling ament_index_cpp with x64 architecture

[iqedgarmg]

Hi everyone!, thanks a lot for this amazing project!

I have an Issue while compiling this package for ros2 foxy with colcon, where the following error appears:

 C:\ws_new\ros_msft_mrtk_native\tools\src\ament\ament_index\ament_index_cpp\src\get_resources.cpp(74,67): error C2664: 'HANDLE FindFirstFileW(LPCWSTR,LPWIN32_FIND_DATAW)': cannot convert argument 1 from 'const _Elem *' to 'LPCWSTR' [C:\ws_new\ros_msft_mrtk_native\tools\x64_build\ament_index_cpp\ament_index_cpp.vcxproj]
          with
          [
              _Elem=char
          ]
C:\ws_new\ros_msft_mrtk_native\tools\src\ament\ament_index\ament_index_cpp\src\get_resources.cpp(89,10): message : Reason: cannot convert from 'WCHAR [260]' to 'const std::basic_string<char,std::char_traits<char>,std::allocator<char>>' [C:\ws_new\ros_msft_mrtk_native\tools\x64_build\ament_index_cpp\ament_index_cpp.vcxproj]
C:\ws_new\ros_msft_mrtk_native\tools\src\ament\ament_index\ament_index_cpp\src\get_resources.cpp(89,10): message : No constructor could take the source type, or constructor overload resolution was ambiguous [C:\ws_new\ros_msft_mrtk_native\tools\x64_build\ament_index_cpp\ament_index_cpp.vcxproj]
C:\Program Files (x86)\Microsoft Visual Studio\2019\Community\VC\Tools\MSVC\14.29.30133\include\xtree(1370,25): message : see declaration of 'std::_Tree<std::_Tmap_traits<_Kty,_Ty,_Pr,_Alloc,false>>::find' [C:\ws_new\ros_msft_mrtk_native\tools\x64_build\ament_index_cpp\ament_index_cpp.vcxproj]

By looking into the get_resources.cpp file, I found that the following code is executed when a different architecture than win32 is used:

#else
    std::string pattern = path + "/*";
    WIN32_FIND_DATA find_data;
    HANDLE find_handle = FindFirstFile(pattern.c_str(), &find_data);
    if (find_handle == INVALID_HANDLE_VALUE) {
      continue;
    }
    do {
      // ignore directories
      if ((find_data.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY)) {
        continue;
      }

      // ignore files starting with a dot
      if (find_data.cFileName[0] == '.') {
        continue;
      }

      if (resources.find(find_data.cFileName) == resources.end()) {
        resources[find_data.cFileName] = base_path;
      }
    } while (FindNextFile(find_handle, &find_data));
    FindClose(find_handle);
#endif
  }
  return resources;
}

As the errors says, the problem is that the compiler can't convert the string from char to wchar. By looking some related issues, I added this additional functions to the main file:

std::wstring s2ws(const std::string& str)
{
    using convert_typeX = std::codecvt_utf8<wchar_t>;
    std::wstring_convert<convert_typeX, wchar_t> converterX;

    return converterX.from_bytes(str);
}

std::string ws2s(const std::wstring& wstr)
{
    using convert_typeX = std::codecvt_utf8<wchar_t>;
    std::wstring_convert<convert_typeX, wchar_t> converterX;

    return converterX.to_bytes(wstr);
}

and then, I developed the required conversions to make the compilation works:

#else

    std::string pattern = path + "/*";

    //---> Patch added
    std::wstring wpattern = s2ws(pattern);

    WIN32_FIND_DATA find_data;
    HANDLE find_handle = FindFirstFile(wpattern.c_str(), &find_data);
    if (find_handle == INVALID_HANDLE_VALUE) {
      continue;
    }
    do {
      // ignore directories
      if ((find_data.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY)) {
        continue;
      }

      // ignore files starting with a dot
      if (find_data.cFileName[0] == '.') {
        continue;
      }

      //---> Patch added
      if (resources.find(ws2s(find_data.cFileName)) == resources.end())
      {
          resources[ws2s(find_data.cFileName)] = base_path;
      }

    } while (FindNextFile(find_handle, &find_data));
    FindClose(find_handle);
#endif
  }
  return resources;
}

In order to skip de error. Nevertheless, despite the package can compile with no problems I am getting an execution error when I create a ros2 node instance. I am not sure if this error is caused by the previous modification, or if I am making a mistake when I try to compile the package. I have a Windows 10 machine with a /x64 architecture, and Visual Studio Community 2019.

Thanks in advance for your response!

[clalancette]

Hm, it is interesting that you are running into that problem, since we compile this nightly on Windows 10 x64 architecture with Visual Studio 2019. You can see the results in https://ci.ros2.org/view/nightly/job/nightly_win_rel/ .

I guess one possibility is that we have our system set to English/ASCII, and you are using a different character set. What character set do you have your Windows machine set to?

[iqedgarmg]

Thanks @clalancette for your quick response!.

Maybe that could be the problem, this is the output of my computer when i run the command "[System.Text.Encoding]::Default":

 IsSingleByte      : True
BodyName          : iso-8859-1
EncodingName      : Western European (Windows)
HeaderName        : Windows-1252
WebName           : Windows-1252
WindowsCodePage   : 1252
IsBrowserDisplay  : True
IsBrowserSave     : True
IsMailNewsDisplay : True
IsMailNewsSave    : True
EncoderFallback   : System.Text.InternalEncoderBestFitFallback
DecoderFallback   : System.Text.InternalDecoderBestFitFallback
IsReadOnly        : True
CodePage          : 1252

As far as I understand, CP-1252 is extended ASCII right?, English is also my system default language.

I tried the compilation in a different Windows 10 machine but the problem still persists.

Thanks in advance for your help and response!