WMI

Created by Thomas Sparber 2016

GOAL

This is a very simple library written in C++ to execute WMI queries. The aim is to make it as simple as possible and stick as much as possible to the C++ standard (avoid Microsoft specific things) so that it even compiles smoothly on MinGW.

Usage

I think it is so simple that a small program explains the usage without any further comments:

    int main(int /*argc*/, char */*args*/[])
    {
        try {
            Win32_ComputerSystem computer = retrieveWmi<Win32_ComputerSystem>();
            Win32_ComputerSystemProduct product  = retrieveWmi<Win32_ComputerSystemProduct>();
            SoftwareLicensingService liscense  = retrieveWmi<SoftwareLicensingService>();
            Win32_OperatingSystem os_info  = retrieveWmi<Win32_OperatingSystem>();

            cout<<"Computername: "<<computer.Name<<" Domaind:"<<computer.Domain<<endl;
            cout<<"Product: "<<product.Name<<" UUID:"<<product.UUID<<endl;
            cout<<"Architecture: "<<os_info.OSArchitecture<<std::endl;
            cout<<"Roles: "<<endl;
            for(const string role : computer.Roles)
            {
                cout<<" - "<<role<<std::endl;
            }
            cout<<endl;
            cout<<"Installed services:"<<endl;
            for(const Win32_Service &service : retrieveAllWmi<Win32_Service>())
            {
                cout<<service.Caption<<endl;
            }
        } catch (const WmiException &ex) {
            cerr<<"Wmi error: "<<ex.errorMessage<<", Code: "<<ex.hexErrorCode()<<endl;
            return 1;
        }

        return 0;
    }

The include file contains all interfaces to execute WMI queries. The include file contains some predefined WMI classes (e.g. Win32_ComputerSystem or Win32_Service...)

Create WMI classes

As already mentioned, the include file provides some standard WMI classes, but it is also very easy to add more of them. All you need to do is:

    struct Win32_MyCustomClass
    {

        /**
          * This function is called by requestWmi and requestAllWmi
          * with the actual WmiResult
         **/
        void setProperties(const WmiResult &result, std::size_t index)
        {
            //EXAMPLE EXTRACTING PROPERTY TO CLASS
            result.extract(index, "name", (*this).name);
        }

        /**
          * This function is used to determine the actual WMI class name
         **/
        static std::string getWmiClassName()
        {
            return "Win32_MyCustomClass";
        }

        /**
          * This function can be optionally implemented if the wmi class
          * is not member of cimv2. In such a case, this function needs
          * to return the root for this WMI class
         **/
        /*static std::string getWmiPath()
        {
            return "not cimv2";
        }*/

        string name;
        //All the other properties you wish to read from WMI

    }; //end struct Win32_ComputerSystem

These two functions are the only requirements your class needs to have.