Function getUserName

src/Common/assertProcessUserMatchesDataOwner.cpp:20–39

namespace
{
    std::string getUserName(uid_t user_id)
    {
        /// Try to convert user id into user name.
        auto buffer_size = sysconf(_SC_GETPW_R_SIZE_MAX);
        if (buffer_size <= 0)
            buffer_size = 1024;
        std::string buffer;
        buffer.reserve(buffer_size);

        struct passwd passwd_entry{};
        struct passwd * result = nullptr;
        const auto error = getpwuid_r(user_id, &passwd_entry, buffer.data(), buffer_size, &result);

        if (error)
            ErrnoException::throwWithErrno(
                ErrorCodes::FAILED_TO_GETPWUID, error, "Failed to find user name for {}", std::to_string(user_id));
        else if (result)
            return result->pw_name;
        return std::to_string(user_id);
    }
}

void assertProcessUserMatchesDataOwner(const std::string & path, std::function<void(const PreformattedMessage &)> on_warning)