public bool TPcastStartChecking()
{
this.StopThread = false;
bool flag = false;
try
{
this.ewh_stopthread = new EventWaitHandle(false, EventResetMode.AutoReset);
this.ewh_devstatus = new EventWaitHandle(false, EventResetMode.ManualReset, "Global\\TPcastDeviceEvent", out this.ewhwasCreated);
}
catch (UnauthorizedAccessException ex)
{
Console.WriteLine("UnauthorizedAccessException: {0}", ex.Message);
flag = true;
}
catch (Exception ex2)
{
Console.WriteLine("Exception: {0}", ex2.Message);
bool result = false;
return(result);
}
if (flag)
{
try
{
this.ewh_devstatus = EventWaitHandle.OpenExisting("Global\\TPcastDeviceEvent", EventWaitHandleRights.ReadPermissions | EventWaitHandleRights.ChangePermissions);
EventWaitHandleSecurity accessControl = this.ewh_devstatus.GetAccessControl();
string expr_9B = Environment.UserDomainName + "\\" + Environment.UserName;
EventWaitHandleAccessRule rule = new EventWaitHandleAccessRule(expr_9B, EventWaitHandleRights.Modify | EventWaitHandleRights.Synchronize, AccessControlType.Deny);
accessControl.RemoveAccessRule(rule);
rule = new EventWaitHandleAccessRule(expr_9B, EventWaitHandleRights.Modify | EventWaitHandleRights.Synchronize, AccessControlType.Allow);
accessControl.AddAccessRule(rule);
this.ewh_devstatus.SetAccessControl(accessControl);
Console.WriteLine("Updated event security.");
this.ewh_devstatus = EventWaitHandle.OpenExisting("Global\\TPcastDeviceEvent");
}
catch (UnauthorizedAccessException ex3)
{
Console.WriteLine("Unable to change permissions: {0}", ex3.Message);
bool result = false;
return(result);
}
}
if (!TPcastRemoteDevices.ThreadIsRunning)
{
TPcastRemoteDevices.ThreadIsRunning = true;
this.workerThread = new Thread(new ParameterizedThreadStart(this.ProcessChecking));
this.workerThread.Start(this);
}
return(true);
}
public static void Main()
{
// Create a string representing the current user.
string user = Environment.UserDomainName + "\\" +
Environment.UserName;
// Create a security object that grants no access.
EventWaitHandleSecurity mSec = new EventWaitHandleSecurity();
// Add a rule that grants the current user the
// right to wait on or signal the event and read the
// permissions on the event.
EventWaitHandleAccessRule rule = new EventWaitHandleAccessRule(user,
EventWaitHandleRights.Synchronize | EventWaitHandleRights.Modify
| EventWaitHandleRights.ReadPermissions,
AccessControlType.Allow);
mSec.AddAccessRule(rule);
// Add a rule that denies the current user the
// right to change permissions on the event.
rule = new EventWaitHandleAccessRule(user,
EventWaitHandleRights.ChangePermissions,
AccessControlType.Deny);
mSec.AddAccessRule(rule);
// Display the rules in the security object.
ShowSecurity(mSec);
// Create a rule that grants the current user
// the right to read permissions on the event, and
// take ownership of the event. Use this rule to
// remove the right to read permissions from the
// Allow rule for the current user. The inclusion
// of the right to take ownership has no effect.
rule = new EventWaitHandleAccessRule(user,
EventWaitHandleRights.TakeOwnership |
EventWaitHandleRights.ReadPermissions,
AccessControlType.Allow);
mSec.RemoveAccessRule(rule);
ShowSecurity(mSec);
}
/// <summary>
/// Creates or opens existing native system event handle.
/// This is an example from:
/// ms-help://MS.VSCC.v80/MS.MSDN.v80/MS.NETDEVFX.v20.en/cpref12/html/M_System_Threading_EventWaitHandle_OpenExisting_1_2aff9ff6.htm
/// </summary>
public static EventWaitHandle CreateOrOpen(string name, EventResetMode mode, bool initialState)
{
EventWaitHandle ewh = null;
bool doesNotExist = false;
bool unauthorized = false;
// The value of this variable is set by the event
// constructor. It is true if the named system event was
// created, and false if the named event already existed.
// Attempt to open the named event.
try
{
// Open the event with (EventWaitHandleRights.Synchronize
// | EventWaitHandleRights.Modify), to wait on and
// signal the named event.
//
ewh = EventWaitHandle.OpenExisting(name);
}
catch (WaitHandleCannotBeOpenedException)
{
//Console.WriteLine("Named event does not exist.");
doesNotExist = true;
}
catch// (UnauthorizedAccessException ex)
{
//Console.WriteLine("Unauthorized access: {0}", ex.Message);
unauthorized = true;
}
// There are three cases: (1) The event does not exist.
// (2) The event exists, but the current user doesn't
// have access. (3) The event exists and the user has
// access.
//
if (doesNotExist)
{
// The event does not exist, so create it.
// Create an access control list (ACL) that denies the
// current user the right to wait on or signal the
// event, but allows the right to read and change
// security information for the event.
//
string user = Environment.UserDomainName + "\\"
+ Environment.UserName;
EventWaitHandleSecurity ewhSec =
new EventWaitHandleSecurity();
EventWaitHandleAccessRule rule;
//=
// new EventWaitHandleAccessRule(user,
// EventWaitHandleRights.Synchronize |
// EventWaitHandleRights.Modify,
// AccessControlType.Deny);
//ewhSec.AddAccessRule(rule);
rule = new EventWaitHandleAccessRule(user,
EventWaitHandleRights.FullControl,
// | EventWaitHandleRights.ReadPermissions |
//EventWaitHandleRights.ChangePermissions | EventWaitHandleRights.Synchronize | EventWaitHandleRights.Modify,
AccessControlType.Allow);
ewhSec.AddAccessRule(rule);
// Create an EventWaitHandle object that represents
// the system event named by the constant 'ewhName',
// initially signaled, with automatic reset, and with
// the specified security access. The Boolean value that
// indicates creation of the underlying system object
// is placed in wasCreated.
//
bool wasCreated;
ewh = new EventWaitHandle(initialState,
mode,
name,
out wasCreated,
ewhSec);
// If the named system event was created, it can be
// used by the current instance of this program, even
// though the current user is denied access. The current
// program owns the event. Otherwise, exit the program.
//
if (wasCreated)
{
//Console.WriteLine("Created the named event.");
}
else
{
//Console.WriteLine("Unable to create the event.");
return(null);
}
}
else if (unauthorized)
{
// Open the event to read and change the access control
// security. The access control security defined above
// allows the current user to do this.
//
try
{
ewh = EventWaitHandle.OpenExisting(name,
EventWaitHandleRights.ReadPermissions |
EventWaitHandleRights.ChangePermissions | EventWaitHandleRights.Modify | EventWaitHandleRights.Synchronize);
// Get the current ACL. This requires
// EventWaitHandleRights.ReadPermissions.
EventWaitHandleSecurity ewhSec = ewh.GetAccessControl();
string user = Environment.UserDomainName + "\\"
+ Environment.UserName;
// First, the rule that denied the current user
// the right to enter and release the event must
// be removed.
EventWaitHandleAccessRule rule =
new EventWaitHandleAccessRule(user,
EventWaitHandleRights.Synchronize |
EventWaitHandleRights.Modify,
AccessControlType.Deny);
ewhSec.RemoveAccessRule(rule);
// Now grant the user the correct rights.
//
rule = new EventWaitHandleAccessRule(user,
EventWaitHandleRights.Synchronize |
EventWaitHandleRights.Modify,
AccessControlType.Allow);
ewhSec.AddAccessRule(rule);
// Update the ACL. This requires
// EventWaitHandleRights.ChangePermissions.
ewh.SetAccessControl(ewhSec);
//Console.WriteLine("Updated event security.");
// Open the event with (EventWaitHandleRights.Synchronize
// | EventWaitHandleRights.Modify), the rights required
// to wait on and signal the event.
//
ewh = EventWaitHandle.OpenExisting(name);
}
catch// (UnauthorizedAccessException ex)
{
//Console.WriteLine("Unable to change permissions: {0}",
// ex.Message);
return(null);
}
}
return(ewh);
}
private EventWaitHandle EventInitialisation(string eventName)
{
EventWaitHandle ewh;
try
{
ewh = EventWaitHandle.OpenExisting(eventName);
}
catch (WaitHandleCannotBeOpenedException)
{
string user = Environment.UserDomainName + "\\"
+ Environment.UserName;
EventWaitHandleSecurity ewhSec =
new EventWaitHandleSecurity();
EventWaitHandleAccessRule rule =
new EventWaitHandleAccessRule(user,
EventWaitHandleRights.Synchronize |
EventWaitHandleRights.Modify,
AccessControlType.Deny);
ewhSec.AddAccessRule(rule);
rule = new EventWaitHandleAccessRule(user,
EventWaitHandleRights.ReadPermissions |
EventWaitHandleRights.ChangePermissions,
AccessControlType.Allow);
ewhSec.AddAccessRule(rule);
ewh = new EventWaitHandle(true,
EventResetMode.AutoReset,
eventName,
out bool wasCreated,
ewhSec);
}
catch (UnauthorizedAccessException)
{
ewh = EventWaitHandle.OpenExisting(eventName,
EventWaitHandleRights.ReadPermissions |
EventWaitHandleRights.ChangePermissions);
EventWaitHandleSecurity ewhSec = ewh.GetAccessControl();
string user = Environment.UserDomainName + "\\"
+ Environment.UserName;
EventWaitHandleAccessRule rule =
new EventWaitHandleAccessRule(user,
EventWaitHandleRights.Synchronize |
EventWaitHandleRights.Modify,
AccessControlType.Deny);
ewhSec.RemoveAccessRule(rule);
rule = new EventWaitHandleAccessRule(user,
EventWaitHandleRights.Synchronize |
EventWaitHandleRights.Modify,
AccessControlType.Allow);
ewhSec.AddAccessRule(rule);
ewh.SetAccessControl(ewhSec);
ewh = EventWaitHandle.OpenExisting(eventName);
}
return(ewh);
}
