Function convert_mbstring_to_wstring

dlib/unicode/unicode.cpp:97–111

// ----------------------------------------------------------------------------------------

    const std::wstring convert_mbstring_to_wstring(const std::string &src)
    {
        // Compute dst length
        std::mbstate_t st{};
        const char* p = src.c_str();
        size_t n = std::mbsrtowcs(nullptr, &p, 0, &st);
        if (n == static_cast<size_t>(-1)) throw std::runtime_error("Invalid multibyte sequence / wrong locale");

        // Convert
        std::wstring out(n, L'\0');
        st = std::mbstate_t{};
        n  = std::mbsrtowcs(&out[0], &p, out.size(), &st);
        if (n == static_cast<size_t>(-1)) throw std::runtime_error("Conversion failed");
        return out;
    }

// ----------------------------------------------------------------------------------------