Why does SetupDiEnumDriverInfo give two version numbers for my driver

Question

I'm trying to get the version number of a driver programmatically. The seems to be done by using SetupDiEnumDriverInfo to get a SP_DRVINFO_DATA struct and inspect the DriverVersion field.

The following code works, but returns two different versions for the same driver. My device is a custom USB device, with a single .sys file. There is only one device connected to my machine. I specify DIGCF_PRESENT to only query the drivers of currently attached devices.

int main(void)
{
    // Get the "device info set" for our driver GUID
    HDEVINFO devInfoSet = SetupDiGetClassDevs(
                              &GUID_DEVINTERFACE_USBSPI, NULL, NULL,
                              DIGCF_PRESENT | DIGCF_DEVICEINTERFACE);

    // Cycle through all devices currently present
    for (int i = 0; ; i++)
    {
        // Get the device info for this device
        SP_DEVINFO_DATA devInfo;
        devInfo.cbSize = sizeof(SP_DEVINFO_DATA);
        if (!SetupDiEnumDeviceInfo(devInfoSet, i, &devInfo))
            break;

        // Build a list of driver info items that we will retrieve below
        if (!SetupDiBuildDriverInfoList(devInfoSet, 
                                        &devInfo, SPDIT_COMPATDRIVER))
            return -1; // Exit on error

        // Get all the info items for this driver 
        // (I don't understand why there is more than one)
        for (int j = 0; ; j++)
        {
            SP_DRVINFO_DATA drvInfo;
            drvInfo.cbSize = sizeof(SP_DRVINFO_DATA);
            if (!SetupDiEnumDriverInfo(devInfoSet, &devInfo, 
                                       SPDIT_COMPATDRIVER, j, &drvInfo))
                break;

            printf("Driver version is %08x %08x\n", 
                   (unsigned)(drvInfo.DriverVersion >> 32), 
                   (unsigned)(drvInfo.DriverVersion & 0xffffffffULL));
        }
    }

    SetupDiDestroyDeviceInfoList(devInfoSet);

    return 0;
}

On my machine this prints:

Driver version is 00000000 000015d3
Driver version is 00020004 00000000

On a friend's machine, it prints:

Driver version is 00020004 00000000
Driver version is 00020004 00000000

The second line matches the number reported by device manager.

Disclaimer: I previously asked a similar question. This is a new question about why SetupDiEnumDriverInfo returns more than one driver version.

Answer 1

As your code is written, all the possible drivers will be output. Try doing the following to filter on only the installed driver:

SP_DEVINSTALL_PARAMS InstallParams;
if ( !SetupDiGetDeviceInstallParams( devInfoSet, &devInfo, &InstallParams ) )
{
   //Error
}
else
{
   InstallParams.FlagsEx |= DI_FLAGSEX_INSTALLEDDRIVER;
   if ( !SetupDiSetDeviceInstallParams( devInfoSet, &devInfo, &InstallParams) )
   {
      //Errror
   }
}

I found this at http://doxygen.reactos.org/df/db2/dll_2win32_2devmgr_2misc_8c_a1cd0b33c1785392a37689433dc99e482.html