IovUnloadDrivers source code v2

NTSTATUS __stdcall IovUnloadDrivers()
{
  NTSTATUS result; // er12@3
  PDRIVER_OBJECT driverObject; // rdi@4 MAPDST
  _DEVICE_OBJECT *DeviceObject; // rsi@7 MAPDST
  char have_next_driver; // bp@16
  PDRIVER_OBJECT *nextDriverObject; // rdi@16
  char have_next_device; // al@16
  PBOOLEAN unloadDriver; // [sp+30h] [bp-78h]@8
  _LARGE_INTEGER Interval; // [sp+38h] [bp-70h]@22
  struct _WORK_QUEUE_ITEM WorkItem; // [sp+40h] [bp-68h]@12
  KEVENT Event; // [sp+60h] [bp-48h]@12

  if ( !PopShutdownCleanly )
    return STATUS_UNSUCCESSFUL;
  IovDriverListHead = 0i64;
  driverObject = 0i64;
  result = ObEnumerateObjectsByType(IoDriverObjectType, IovpBuildDriverObjectList, 0i64);
  while ( 1 )
  {
    driverObject = IovDriverListHead;
    if ( IovDriverListHead )
      IovDriverListHead = *IovDriverListHead;
    if ( !driverObject )
      break;
    DeviceObject = driverObject->DeviceObject;
    if ( !DeviceObject->Queue.Wcb.DeviceRoutine )
      goto LABEL_14;
    ObfReferenceObject(driverObject->DeviceObject);
    if ( IopCheckUnloadDriver(DeviceObject, &unloadDriver) < 0 && (ObfDereferenceObject(DeviceObject), unloadDriver) )
    {
      if ( IovpUnloadDriver(driverObject) == PsInitialSystemProcess )
      {
        (DeviceObject->Queue.Wcb.DeviceRoutine)(DeviceObject);
      }
      else
      {
        KeInitializeEvent(&Event, NotificationEvent, FALSE);
        ExInitializeWorkItem(WorkItem, IopLoadUnloadDriver, WorkItem);
        ExQueueWorkItem(&WorkItem, DelayedWorkQueue);
        KeWaitForSingleObject(&Event, 0, 0, 0, 0i64);
      }
      ObMakeTemporaryObject(DeviceObject);
      ObfDereferenceObject(DeviceObject);
LABEL_14:
      ObfDereferenceObject(driverObject->DeviceObject);
      ExFreePoolWithTag(driverObject, 0);
    }
    else
    {
      *&driverObject->Type = driverObject;
    }
  }
  do
  {
    have_next_driver = 0;
    nextDriverObject = 0i64;
    have_next_device = 0;
    while ( driverObject )
    {
      DeviceObject = driverObject->DeviceObject;
      driverObject = *&driverObject->Type;
      if ( DeviceObject->NextDevice & 1 )
      {
        ObfDereferenceObject(DeviceObject);
        ExFreePoolWithTag(driverObject, 0);
        have_next_device = 1;
      }
      else
      {
        *&driverObject->Type = nextDriverObject;
        nextDriverObject = driverObject;
      }
    }
    if ( have_next_device )
    {
      Interval.QuadPart = -100000000i64;
      ZwDelayExecution(0i64, &Interval);
      have_next_driver = 1;
    }
    driverObject = nextDriverObject;
  }
  while ( have_next_driver == 1 && nextDriverObject );
  while ( driverObject )
  {
    DeviceObject = driverObject->DeviceObject;
    driverObject = *&driverObject->Type;
    ObfDereferenceObject(DeviceObject);
    ExFreePoolWithTag(driverObject, 0);
  }
  return result;
}