1 files changed, 256 insertions, 0 deletions

diff --git a/private/ntos/tdi/st/devctx.c b/private/ntos/tdi/st/devctx.c
new file mode 100644
index 000000000..94cc2f385
--- /dev/null
+++ b/private/ntos/tdi/st/devctx.c
@@ -0,0 +1,256 @@
+/*++
+
+Copyright (c) 1989-1993  Microsoft Corporation
+
+Module Name:
+
+    devctx.c
+
+Abstract:
+
+    This module contains code which implements the DEVICE_CONTEXT object.
+    Routines are provided to reference, and dereference transport device
+    context objects.
+
+    The transport device context object is a structure which contains a
+    system-defined DEVICE_OBJECT followed by information which is maintained
+    by the transport provider, called the context.
+
+Environment:
+
+    Kernel mode
+
+Revision History:
+
+--*/
+
+#include "st.h"
+
+
+VOID
+StRefDeviceContext(
+    IN PDEVICE_CONTEXT DeviceContext
+    )
+
+/*++
+
+Routine Description:
+
+    This routine increments the reference count on a device context.
+
+Arguments:
+
+    DeviceContext - Pointer to a transport device context object.
+
+Return Value:
+
+    none.
+
+--*/
+
+{
+    ASSERT (DeviceContext->ReferenceCount > 0);    // not perfect, but...
+
+    (VOID)InterlockedIncrement (&DeviceContext->ReferenceCount);
+
+} /* StRefDeviceContext */
+
+
+VOID
+StDerefDeviceContext(
+    IN PDEVICE_CONTEXT DeviceContext
+    )
+
+/*++
+
+Routine Description:
+
+    This routine dereferences a device context by decrementing the
+    reference count contained in the structure.  Currently, we don't
+    do anything special when the reference count drops to zero, but
+    we could dynamically unload stuff then.
+
+Arguments:
+
+    DeviceContext - Pointer to a transport device context object.
+
+Return Value:
+
+    none.
+
+--*/
+
+{
+    LONG result;
+
+    result = InterlockedDecrement (&DeviceContext->ReferenceCount);
+
+    ASSERT (result >= 0);
+
+    if (result == 0) {
+        StDestroyDeviceContext (DeviceContext);
+    }
+
+} /* StDerefDeviceContext */
+
+
+
+NTSTATUS
+StCreateDeviceContext(
+    IN PDRIVER_OBJECT DriverObject,
+    IN PUNICODE_STRING DeviceName,
+    IN OUT PDEVICE_CONTEXT *DeviceContext
+    )
+
+/*++
+
+Routine Description:
+
+    This routine creates and initializes a device context structure.
+
+Arguments:
+
+
+    DriverObject - pointer to the IO subsystem supplied driver object.
+
+    DeviceContext - Pointer to a pointer to a transport device context object.
+
+    DeviceName - pointer to the name of the device this device object points to.
+
+Return Value:
+
+    STATUS_SUCCESS if all is well; STATUS_INSUFFICIENT_RESOURCES otherwise.
+
+--*/
+
+{
+    NTSTATUS status;
+    PDEVICE_OBJECT deviceObject;
+    PDEVICE_CONTEXT deviceContext;
+    USHORT i;
+
+
+    //
+    // Create the device object for the sample transport, allowing
+    // room at the end for the device name to be stored (for use
+    // in logging errors).
+    //
+
+    status = IoCreateDevice(
+                 DriverObject,
+                 sizeof (DEVICE_CONTEXT) - sizeof (DEVICE_OBJECT) +
+                     (DeviceName->Length + sizeof(UNICODE_NULL)),
+                 DeviceName,
+                 FILE_DEVICE_TRANSPORT,
+                 0,
+                 FALSE,
+                 &deviceObject);
+
+    if (!NT_SUCCESS(status)) {
+        return status;
+    }
+
+    deviceObject->Flags |= DO_DIRECT_IO;
+
+    deviceContext = (PDEVICE_CONTEXT)deviceObject;
+
+    //
+    // Initialize our part of the device context.
+    //
+
+    RtlZeroMemory(
+        ((PUCHAR)deviceContext) + sizeof(DEVICE_OBJECT),
+        sizeof(DEVICE_CONTEXT) - sizeof(DEVICE_OBJECT));
+
+    //
+    // Copy over the device name.
+    //
+
+    deviceContext->DeviceNameLength = DeviceName->Length + sizeof(WCHAR);
+    deviceContext->DeviceName = (PWCHAR)(deviceContext+1);
+    RtlCopyMemory(
+        deviceContext->DeviceName,
+        DeviceName->Buffer,
+        DeviceName->Length);
+    deviceContext->DeviceName[DeviceName->Length/sizeof(WCHAR)] = UNICODE_NULL;
+
+    //
+    // Initialize the reference count.
+    //
+
+    deviceContext->ReferenceCount = 1;
+
+    //
+    // initialize the various fields in the device context
+    //
+
+    KeInitializeSpinLock (&deviceContext->Interlock);
+    KeInitializeSpinLock (&deviceContext->SpinLock);
+
+    deviceContext->ControlChannelIdentifier = 1;
+
+    InitializeListHead (&deviceContext->ConnectionPool);
+    InitializeListHead (&deviceContext->AddressPool);
+    InitializeListHead (&deviceContext->AddressFilePool);
+    InitializeListHead (&deviceContext->AddressDatabase);
+    InitializeListHead (&deviceContext->PacketWaitQueue);
+    InitializeListHead (&deviceContext->PacketizeQueue);
+    InitializeListHead (&deviceContext->RequestPool);
+    deviceContext->PacketPool.Next = NULL;
+    deviceContext->ReceivePacketPool.Next = NULL;
+    deviceContext->ReceiveBufferPool.Next = NULL;
+    InitializeListHead (&deviceContext->ReceiveInProgress);
+    InitializeListHead (&deviceContext->IrpCompletionQueue);
+
+
+    deviceContext->State = DEVICECONTEXT_STATE_CLOSED;
+
+    //
+    // Initialize the resource that guards address ACLs.
+    //
+
+    ExInitializeResource (&deviceContext->AddressResource);
+
+    //
+    // set the netbios multicast address for this network type
+    //
+
+    for (i=0; i<HARDWARE_ADDRESS_LENGTH; i++) {
+        deviceContext->LocalAddress.Address [i] = 0; // set later
+        deviceContext->MulticastAddress.Address [i] = 0;
+    }
+
+     deviceContext->Type = ST_DEVICE_CONTEXT_SIGNATURE;
+     deviceContext->Size - sizeof (DEVICE_CONTEXT);
+
+    *DeviceContext = deviceContext;
+    return STATUS_SUCCESS;
+}
+
+
+VOID
+StDestroyDeviceContext(
+    IN PDEVICE_CONTEXT DeviceContext
+    )
+
+/*++
+
+Routine Description:
+
+    This routine destroys a device context structure.
+
+Arguments:
+
+    DeviceContext - Pointer to a pointer to a transport device context object.
+
+Return Value:
+
+    None.
+
+--*/
+
+{
+    ExDeleteResource (&DeviceContext->AddressResource);
+    IoDeleteDevice ((PDEVICE_OBJECT)DeviceContext);
+    return;
+}