Initial publish

1 files changed, 73 insertions, 0 deletions

diff --git a/general/obcallback/driver/util.c b/general/obcallback/driver/util.c
new file mode 100644
index 00000000..c00e96a3
--- /dev/null
+++ b/general/obcallback/driver/util.c
@@ -0,0 +1,73 @@
+/*++
+
+Module Name:
+
+    util.c
+
+Notice:
+    Use this sample code at your own risk; there is no support from Microsoft for the sample code.
+    In addition, this sample code is licensed to you under the terms of the Microsoft Public License
+    (http://www.microsoft.com/opensource/licenses.mspx)
+
+
+--*/
+
+#include "pch.h"
+#include "tdriver.h"
+
+//
+// TdSetCallContext
+//
+// Creates a call context object and stores a pointer to it
+// in the supplied OB_PRE_OPERATION_INFORMATION structure.
+//
+// This function is called from a pre-notification. The created call context
+// object then has to be freed in a corresponding post-notification using
+// TdCheckAndFreeCallContext.
+//
+
+void TdSetCallContext (
+    _Inout_ POB_PRE_OPERATION_INFORMATION PreInfo,
+    _In_ PTD_CALLBACK_REGISTRATION CallbackRegistration
+)
+{
+    PTD_CALL_CONTEXT CallContext;
+
+    CallContext = (PTD_CALL_CONTEXT) ExAllocatePoolWithTag (
+        PagedPool, sizeof(TD_CALL_CONTEXT), TD_CALL_CONTEXT_TAG
+    );
+
+    if (CallContext == NULL)
+    {
+        return;
+    }
+
+    RtlZeroMemory (CallContext, sizeof(TD_CALL_CONTEXT));
+
+    CallContext->CallbackRegistration = CallbackRegistration;
+    CallContext->Operation  = PreInfo->Operation;
+    CallContext->Object     = PreInfo->Object;
+    CallContext->ObjectType = PreInfo->ObjectType;
+
+    PreInfo->CallContext = CallContext;
+}
+
+void TdCheckAndFreeCallContext (
+    _Inout_ POB_POST_OPERATION_INFORMATION PostInfo,
+    _In_ PTD_CALLBACK_REGISTRATION CallbackRegistration
+)
+{
+    PTD_CALL_CONTEXT CallContext = (PTD_CALL_CONTEXT)PostInfo->CallContext;
+
+    if (CallContext != NULL)
+    {
+        TD_ASSERT (CallContext->CallbackRegistration == CallbackRegistration);
+
+        TD_ASSERT (CallContext->Operation  == PostInfo->Operation);
+        TD_ASSERT (CallContext->Object     == PostInfo->Object);
+        TD_ASSERT (CallContext->ObjectType == PostInfo->ObjectType);
+
+        ExFreePoolWithTag (CallContext, TD_CALL_CONTEXT_TAG);
+    }
+}
+