/// <summary>
/// Explicitly frees this end of the channel.
///
/// Since both threads on the channel could try to do this simultaneously,
/// we use the ref counting on the underlying endpoints to let the last
/// free operation (the one pulling the ref count to 0) to free the associated
/// event.
/// </summary>
public unsafe static void Free(Allocation * /*EndpointCore* opt(ExHeap)!*/ endpoint)
{
// Use unchecked GetData here, since this may be called from the
// cleanup threading running in the kernel.
EndpointCore *ep = ((EndpointCore *)Allocation.GetDataUnchecked(endpoint));
if (ep->deliveryHandle != DeliveryHandle.Zero)
{
if (DeliveryHandle.Free(ep->deliveryHandle))
{
Interlocked.Decrement(ref openChannelCount);
}
}
else
{
// was never connected, just free this endpoint
AutoResetEventHandle areHandle = ep->cachedMessageEvent;
SharedHeap.KernelSharedHeap.Free(endpoint,
SharedHeap.CurrentProcessSharedHeap.EndpointPeerOwnerId);
if (areHandle.id != UIntPtr.Zero)
{
Process.kernelProcess.ReleaseHandle(areHandle.id);
}
}
}
/// <summary>
/// The peer thread might try this too, so we use the ref count of the
/// underlying memory to allow only the last freeer to also free the
/// associated auto-reset event handle. Make sure to grab the handle
/// before freeing the endpoint.
/// </summary>
unsafe private static bool TryFreeResources(
Allocation * /*EndpointCore*/ endpoint,
SharedHeap.AllocationOwnerId ownerId)
{
EndpointCore *epData =
(EndpointCore *)Allocation.GetDataUnchecked(endpoint);
AutoResetEventHandle areHandle = epData->GetAreHandle();
DeliveryHandle dh = epData->dImpHandle;
int channelId = epData->ChannelId;
bool lastRefGone = SharedHeap.KernelSharedHeap.Free(endpoint,
ownerId);
if (lastRefGone)
{
if (dh != DeliveryHandle.Zero)
{
DeliveryHandle.Dispose(dh);
}
if (areHandle.id != UIntPtr.Zero)
{
Process.kernelProcess.ReleaseHandle(areHandle.id);
}
}
return(lastRefGone);
}
public static int GetPeerProcessID(ref EndpointCore ep)
{
if (ep.peerStateValid)
{
EndpointCore *peer = (EndpointCore *)SharedHeapService.GetData(ep.cachedPeer);
return(peer->cachedOwnerProcessId);
}
else
{
return(GetPeerProcessIDABI(ref ep));
}
}
public static bool PeerClosed(ref EndpointCore ep)
{
if (ep.cachedPeer != null)
{
EndpointCore *peer = (EndpointCore *)SharedHeapService.GetData(ep.cachedPeer);
return(peer->cachedClosed);
}
else
{
return(PeerClosedABI(ref ep));
}
}
internal static DeliveryImpl AllocationEndpointDeliveryImplUnchecked(
Allocation * /*EndpointCore* opt(ExHeap)!*/ endpoint)
{
EndpointCore *ep = (EndpointCore *)Allocation.GetDataUnchecked(endpoint);
if (ep == null)
{
return(null);
}
else
{
return(ep->EndpointDeliveryImpl);
}
}
/// <summary>
/// Performs the initialization of the core part of each endpoint and cross links
/// them to form a channel. Uses the given delivery mechanism.
/// </summary>
public static void Connect(
Allocation * /*EndpointCore* opt(ExHeap)!*/ imp,
Allocation * /*EndpointCore* opt(ExHeap)!*/ exp,
Allocation * /*EndpointCore* opt(ExHeap)!*/ securityEp,
string deliveryImplType)
{
if (imp == null || exp == null)
{
throw new ApplicationException("Connect called with null endpoints");
}
EndpointCore *impData = (EndpointCore *)Allocation.GetData(imp);
EndpointCore *expData = (EndpointCore *)Allocation.GetData(exp);
if (impData == null || expData == null)
{
throw new ApplicationException("SharedHeap.GetData return null");
}
Tracing.Log(Tracing.Debug, "connect {0:x8} and {1:x8}",
(UIntPtr)imp, (UIntPtr)exp);
if (!(DeliveryHandle.Create(deliveryImplType, imp, out impData->deliveryHandle) &&
DeliveryHandle.Create(deliveryImplType, exp, out expData->deliveryHandle)))
{
throw new EndpointCoreException(
"Error trying to create EndpointCore using \"" +
deliveryImplType +
"\" delivery implementation");
}
#if false
DebugStub.Print("imp handle {0,8:x} exp handle {1,8:x}\n",
__arglist((uint)impData->deliveryHandle.id, (uint)expData->deliveryHandle.id));
#endif
DeliveryImpl impDi = impData->EndpointDeliveryImpl;
DeliveryImpl expDi = expData->EndpointDeliveryImpl;
VTable.Assert(impDi != null && expDi != null);
impDi.Connect(expDi, securityEp);
// keep track of how many channels are open
Interlocked.Increment(ref openChannelCount);
#if CHANNEL_COUNT
PerfCounters.IncrementChannelsCreated();
#endif
Monitoring.Log(Monitoring.Provider.EndpointCore,
(ushort)EndpointCoreEvent.Connect, 0,
(uint)expData->ChannelId, 0, 0, 0, 0);
}
// requires alloc's owner unlocked
private unsafe void EndpointVisit(SharedHeap.Allocation *alloc)
{
// TODO: support PAGING
#if !PAGING
EndpointCore *epData = (EndpointCore *)
// Currently use unchecked access here, since the shared heap
// walker does not run in the same process as the data.
SharedHeap.Allocation.GetDataUnchecked(alloc);
if (!epData->Closed())
{
epData->Dispose();
}
EndpointCore.Free(alloc);
#endif //PAGING
}
////////////////////////////////////////////////////////////////////
// Class Methods
//
internal DeliveryImpl(Allocation * /*EndpointCore* opt(ExHeap)!*/ ep)
{
this.endpointAlloc = ep;
this.endpoint = ((EndpointCore *)Allocation.GetData(ep));
// set default values (shadow cached values in EndpointCore if necessary)
setMessageEvent(new AutoResetEventHandle(
Process.kernelProcess.AllocateHandle(new AutoResetEvent(false))));
endpoint->CollectionEvent = new AutoResetEventHandle();
endpoint->SetCachedPeer(null); // set as null by default
ProcessId = Thread.CurrentProcess.ProcessId;
ChannelId = 0; // zero initially, corrected in connect
Marshall = false; // false by default
Closed = true; // opened in connect
principalHandle = new PrincipalHandle(Thread.CurrentProcess.Principal.Val);
delegationState = DelegationState.None;
receiveCount = 0;
}
