private void WindowsKillProcessTree()
{
var pid = _proc?.Id;
if (pid == null)
{
// process already exit, stop here.
return;
}
Dictionary <int, int> processRelationship = new Dictionary <int, int>();
//Trace.Info($"Scan all processes to find relationship between all processes.");
foreach (Process proc in Process.GetProcesses())
{
try
{
if (!proc.SafeHandle.IsInvalid)
{
ProccessData pbi = new ProccessData();
int returnLength = 0;
int queryResult = NtQueryInformationProcess(proc.SafeHandle.DangerousGetHandle(), PROCESSINFOCLASS.ProcessBasicInformation, ref pbi, Marshal.SizeOf(pbi), ref returnLength);
if (queryResult == 0) // == 0 is OK
{
//Trace.Verbose($"Process: {proc.Id} is child process of {pbi.InheritedFromUniqueProcessId}.");
processRelationship[proc.Id] = (int)pbi.InheritedFromUniqueProcessId;
}
else
{
throw new Win32Exception(Marshal.GetLastWin32Error());
}
}
}
catch (Exception ex)
{
// Ignore all exceptions, since KillProcessTree is best effort.
//Trace.Verbose("Ignore any catched exception during detecting process relationship.");
//Trace.Verbose(ex.ToString());
}
}
//Trace.Verbose($"Start killing process tree of process '{pid.Value}'.");
Stack <ProcessTermination> processesNeedtoKill = new Stack <ProcessTermination>();
processesNeedtoKill.Push(new ProcessTermination(pid.Value, false));
while (processesNeedtoKill.Count() > 0)
{
ProcessTermination procInfo = processesNeedtoKill.Pop();
List <int> childProcessesIds = new List <int>();
if (!procInfo.ChildPidExpanded)
{
//Trace.Info($"Find all child processes of process '{procInfo.Pid}'.");
childProcessesIds = processRelationship.Where(p => p.Value == procInfo.Pid).Select(k => k.Key).ToList();
}
if (childProcessesIds.Count > 0)
{
//Trace.Info($"Need kill all child processes trees before kill process '{procInfo.Pid}'.");
processesNeedtoKill.Push(new ProcessTermination(procInfo.Pid, true));
foreach (var childPid in childProcessesIds)
{
//Trace.Info($"Child process '{childPid}' needs be killed first.");
processesNeedtoKill.Push(new ProcessTermination(childPid, false));
}
}
else
{
//Trace.Info($"Kill process '{procInfo.Pid}'.");
try
{
Process leafProcess = Process.GetProcessById(procInfo.Pid);
try
{
leafProcess.Kill();
}
catch (InvalidOperationException ex)
{
// The process has already exited
//Trace.Verbose("Ignore InvalidOperationException during Process.Kill().");
//Trace.Verbose(ex.ToString());
}
catch (Win32Exception ex) when(ex.NativeErrorCode == 5)
{
// The associated process could not be terminated
// The process is terminating
// NativeErrorCode 5 means Access Denied
//Trace.Verbose("Ignore Win32Exception with NativeErrorCode 5 during Process.Kill().");
//Trace.Verbose(ex.ToString());
}
catch (Exception ex)
{
// Ignore any additional exception
//Trace.Verbose("Ignore additional exceptions during Process.Kill().");
//Trace.Verbose(ex.ToString());
}
}
catch (ArgumentException ex)
{
// process already gone, nothing needs killed.
//Trace.Verbose("Ignore ArgumentException during Process.GetProcessById().");
//Trace.Verbose(ex.ToString());
}
catch (Exception ex)
{
// Ignore any additional exception
//Trace.Verbose("Ignore additional exceptions during Process.GetProcessById().");
//Trace.Verbose(ex.ToString());
}
}
}
}
private static extern int NtQueryInformationProcess(IntPtr processHandle, PROCESSINFOCLASS processInformationClass, ref ProccessData processInformation, int processInformationLength, ref int returnLength);
