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https://github.com/reactos/reactos.git
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[AUDIT]
- Add proper function headers, including links to publically-available documentation - One internal function is subject to further review/audit svn path=/trunk/; revision=22672
This commit is contained in:
Aleksey Bragin
parent
6ef4e4d9d4
commit
981fde0f9f
1 changed files with 363 additions and 354 deletions
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@ -1,9 +1,10 @@
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/*
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* COPYRIGHT: See COPYING in the top level directory
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* PROJECT: ReactOS kernel
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* PROJECT: ReactOS Kernel
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* LICENSE: GPL - See COPYING in the top level directory
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* FILE: ntoskrnl/ex/callback.c
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* PURPOSE: Executive callbacks
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* PROGRAMMERS: Alex Ionescu (alex@relsoft.net)
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* PROGRAMMERS: Filip Navara
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* Alex Ionescu (alex@relsoft.net)
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*/
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/* INCLUDES *****************************************************************/
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@ -63,433 +64,441 @@ KEVENT ExpCallbackEvent;
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/* FUNCTIONS *****************************************************************/
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/*
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* ExpInitializeCallbacks
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/*++
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* @name ExpInitializeCallbacks
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*
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* FUNCTION:
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* Creates the Callback Object as a valid Object Type in the Kernel.
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* Internal function, subject to further review
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*
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* ARGUMENTS:
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* None
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* @return TRUE if the Callback Object Type was successfully created.
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*
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* RETURNS:
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* TRUE if the Callback Object Type was successfully created.
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*/
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* @remarks None
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*
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*--*/
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VOID
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INIT_FUNCTION
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STDCALL
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NTAPI
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ExpInitializeCallbacks(VOID)
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{
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OBJECT_ATTRIBUTES ObjectAttributes;
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NTSTATUS Status;
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UNICODE_STRING DirName = RTL_CONSTANT_STRING(L"\\Callback");
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UNICODE_STRING CallbackName;
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UNICODE_STRING Name;
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OBJECT_TYPE_INITIALIZER ObjectTypeInitializer;
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HANDLE DirectoryHandle;
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ULONG i;
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OBJECT_ATTRIBUTES ObjectAttributes;
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NTSTATUS Status;
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UNICODE_STRING DirName = RTL_CONSTANT_STRING(L"\\Callback");
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UNICODE_STRING CallbackName;
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UNICODE_STRING Name;
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OBJECT_TYPE_INITIALIZER ObjectTypeInitializer;
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HANDLE DirectoryHandle;
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ULONG i;
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/* Initialize the Callback Object type */
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RtlZeroMemory(&ObjectTypeInitializer, sizeof(ObjectTypeInitializer));
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RtlInitUnicodeString(&Name, L"Callback");
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ObjectTypeInitializer.Length = sizeof(ObjectTypeInitializer);
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ObjectTypeInitializer.DefaultNonPagedPoolCharge = sizeof(CALLBACK_OBJECT);
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ObjectTypeInitializer.GenericMapping = ExpCallbackMapping;
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ObjectTypeInitializer.PoolType = NonPagedPool;
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/* Initialize the Callback Object type */
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RtlZeroMemory(&ObjectTypeInitializer, sizeof(ObjectTypeInitializer));
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RtlInitUnicodeString(&Name, L"Callback");
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ObjectTypeInitializer.Length = sizeof(ObjectTypeInitializer);
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ObjectTypeInitializer.DefaultNonPagedPoolCharge = sizeof(CALLBACK_OBJECT);
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ObjectTypeInitializer.GenericMapping = ExpCallbackMapping;
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ObjectTypeInitializer.PoolType = NonPagedPool;
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Status = ObCreateObjectType(&Name, &ObjectTypeInitializer, NULL, &ExCallbackObjectType);
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Status = ObCreateObjectType(&Name, &ObjectTypeInitializer, NULL, &ExCallbackObjectType);
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/* Fail if it wasn't created successfully */
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if (!NT_SUCCESS(Status))
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{
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return;
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}
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/* Fail if it wasn't created successfully */
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if (!NT_SUCCESS(Status))
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{
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return;
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}
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/* Initialize the Object */
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InitializeObjectAttributes(
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&ObjectAttributes,
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&DirName,
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OBJ_CASE_INSENSITIVE | OBJ_PERMANENT,
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NULL,
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NULL
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);
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/* Initialize the Object */
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InitializeObjectAttributes(
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&ObjectAttributes,
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&DirName,
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OBJ_CASE_INSENSITIVE | OBJ_PERMANENT,
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NULL,
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NULL
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);
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/* Create the Object Directory */
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Status = NtCreateDirectoryObject(
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&DirectoryHandle,
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DIRECTORY_ALL_ACCESS,
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&ObjectAttributes
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/* Create the Object Directory */
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Status = NtCreateDirectoryObject(
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&DirectoryHandle,
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DIRECTORY_ALL_ACCESS,
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&ObjectAttributes
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);
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/* Fail if couldn't create */
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if (!NT_SUCCESS(Status))
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{
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return;
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}
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/* Close Handle... */
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NtClose(DirectoryHandle);
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/* Initialize Event used when unregistering */
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KeInitializeEvent(&ExpCallbackEvent, NotificationEvent, 0);
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/* Default NT Kernel Callbacks. */
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for (i=0; ExpInitializeCallback[i].CallbackObject; i++)
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{
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/* Create the name from the structure */
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RtlInitUnicodeString(&CallbackName, ExpInitializeCallback[i].Name);
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/* Initialize the Object Attributes Structure */
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InitializeObjectAttributes(
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&ObjectAttributes,
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&CallbackName,
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OBJ_PERMANENT | OBJ_CASE_INSENSITIVE,
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NULL,
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NULL
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);
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/* Fail if couldn't create */
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if (!NT_SUCCESS(Status))
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{
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return;
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}
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/* Create the Callback Object */
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Status = ExCreateCallback(
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(PCALLBACK_OBJECT*)&(ExpInitializeCallback[i].CallbackObject),
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&ObjectAttributes,
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TRUE,
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TRUE
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);
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/* Close Handle... */
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NtClose(DirectoryHandle);
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/* Initialize Event used when unregistering */
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KeInitializeEvent(&ExpCallbackEvent, NotificationEvent, 0);
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/* Default NT Kernel Callbacks. */
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for (i=0; ExpInitializeCallback[i].CallbackObject; i++)
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{
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/* Create the name from the structure */
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RtlInitUnicodeString(&CallbackName, ExpInitializeCallback[i].Name);
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/* Initialize the Object Attributes Structure */
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InitializeObjectAttributes(
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&ObjectAttributes,
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&CallbackName,
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OBJ_PERMANENT | OBJ_CASE_INSENSITIVE,
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NULL,
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NULL
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);
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/* Create the Callback Object */
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Status = ExCreateCallback(
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(PCALLBACK_OBJECT*)&(ExpInitializeCallback[i].CallbackObject),
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&ObjectAttributes,
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TRUE,
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TRUE
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);
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/* Make sure Global Callbacks have been created */
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if (!NT_SUCCESS(Status))
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{
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return;
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}
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}
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/* Everything successful */
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/* Make sure Global Callbacks have been created */
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if (!NT_SUCCESS(Status))
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{
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return;
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}
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}
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/* Everything successful */
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}
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/*
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* ExCreateCallback
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/*++
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* @name ExCreateCallback
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* @implemented
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*
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* FUNCTION:
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* Opens or creates a Callback Object. Creates only if Create is true.
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* Allows multiple Callback Functions to be registred only if AllowMultipleCallbacks
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* is true.
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* Allows multiple Callback Functions to be registred only if
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* AllowMultipleCallbacks is true.
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* See: http://www.osronline.com/ddkx/kmarch/k102_967m.htm
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* http://www.osronline.com/article.cfm?id=24
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*
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* ARGUMENTS:
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* CallbackObject = Pointer that will receive the Callback Object.
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* CallbackName = Name of Callback
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* Create = Determines if the object will be created if it doesn't exit
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* AllowMultipleCallbacks = Determines if more then one registered callback function
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* can be attached to this Callback Object.
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* @param CallbackObject
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* Pointer that will receive the Callback Object.
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*
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* RETURNS:
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* STATUS_SUCESS if not failed.
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* @param CallbackName
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* Name of Callback
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*
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* @implemented
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*/
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* @param Create
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* Determines if the object will be created if it doesn't exit
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*
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* @param AllowMultipleCallbacks
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* Determines if more then one registered callback function
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* can be attached to this Callback Object.
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*
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* @return STATUS_SUCESS if not failed.
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*
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* @remarks Must be called at IRQL = PASSIVE_LEVEL
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*
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*--*/
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NTSTATUS
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STDCALL
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ExCreateCallback(
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OUT PCALLBACK_OBJECT *CallbackObject,
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IN POBJECT_ATTRIBUTES ObjectAttributes,
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IN BOOLEAN Create,
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IN BOOLEAN AllowMultipleCallbacks
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)
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NTAPI
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ExCreateCallback(OUT PCALLBACK_OBJECT *CallbackObject,
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IN POBJECT_ATTRIBUTES ObjectAttributes,
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IN BOOLEAN Create,
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IN BOOLEAN AllowMultipleCallbacks)
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{
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PCALLBACK_OBJECT Callback;
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NTSTATUS Status;
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HANDLE Handle;
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PCALLBACK_OBJECT Callback;
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NTSTATUS Status;
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HANDLE Handle;
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PAGED_CODE();
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PAGED_CODE();
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/* Open a handle to the callback if it exists */
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if (ObjectAttributes->ObjectName)
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{
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Status = ObOpenObjectByName(ObjectAttributes,
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ExCallbackObjectType,
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KernelMode,
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NULL,
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0,
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NULL,
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&Handle);
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}
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else
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{
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Status = STATUS_UNSUCCESSFUL;
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}
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/* Open a handle to the callback if it exists */
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if (ObjectAttributes->ObjectName)
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{
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Status = ObOpenObjectByName(ObjectAttributes,
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ExCallbackObjectType,
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KernelMode,
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NULL,
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0,
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NULL,
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&Handle);
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}
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else
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{
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Status = STATUS_UNSUCCESSFUL;
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}
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/* We weren't able to open it...should we create it? */
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if(!NT_SUCCESS(Status) && Create )
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{
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Status = ObCreateObject(KernelMode,
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ExCallbackObjectType,
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ObjectAttributes,
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KernelMode,
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NULL,
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sizeof(CALLBACK_OBJECT),
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0,
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0,
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(PVOID *)&Callback );
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/* We weren't able to open it...should we create it? */
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if(!NT_SUCCESS(Status) && Create )
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{
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Status = ObCreateObject(KernelMode,
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ExCallbackObjectType,
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ObjectAttributes,
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KernelMode,
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NULL,
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sizeof(CALLBACK_OBJECT),
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0,
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0,
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(PVOID *)&Callback );
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/* We Created it...let's initialize the structure now */
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if(NT_SUCCESS(Status))
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{
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KeInitializeSpinLock (&Callback->Lock); /* SpinLock */
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InitializeListHead(&Callback->RegisteredCallbacks); /* Callback Entries */
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Callback->AllowMultipleCallbacks = AllowMultipleCallbacks; /* Multiple Callbacks */
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Status = ObInsertObject ( /* Create the object */
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Callback,
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NULL,
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FILE_READ_DATA,
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0,
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NULL,
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&Handle );
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}
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}
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if(NT_SUCCESS(Status))
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{
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/* We Created it...let's initialize the structure now */
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if(NT_SUCCESS(Status))
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{
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KeInitializeSpinLock(&Callback->Lock); /* SpinLock */
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InitializeListHead(&Callback->RegisteredCallbacks); /* Callback Entries */
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Callback->AllowMultipleCallbacks = AllowMultipleCallbacks; /* Multiple Callbacks */
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/* Create the object */
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Status = ObInsertObject(Callback,
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NULL,
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FILE_READ_DATA,
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0,
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NULL,
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&Handle );
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}
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}
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/* Get a pointer to the new object from the handle we just got */
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Status = ObReferenceObjectByHandle (
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Handle,
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0,
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ExCallbackObjectType,
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KernelMode,
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(PVOID)&Callback,
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NULL
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);
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/* Close the Handle, since we now have the pointer */
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ZwClose(Handle);
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}
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if(NT_SUCCESS(Status))
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{
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/* Get a pointer to the new object from the handle we just got */
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Status = ObReferenceObjectByHandle(Handle,
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0,
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ExCallbackObjectType,
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KernelMode,
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(PVOID)&Callback,
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NULL);
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/* Close the Handle, since we now have the pointer */
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ZwClose(Handle);
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}
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/* Everything went fine, so return a pointer to the Object */
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if (NT_SUCCESS(Status))
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{
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*CallbackObject = (PCALLBACK_OBJECT)Callback;
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}
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return Status;
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/* Everything went fine, so return a pointer to the Object */
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if (NT_SUCCESS(Status))
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{
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*CallbackObject = (PCALLBACK_OBJECT)Callback;
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}
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return Status;
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}
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/*
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* ExNotifyCallback
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*
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* FUNCTION:
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* Calls a function pointer (a registered callback)
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*
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* ARGUMENTS:
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* CallbackObject - Which callback to call
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* Argument1 - Pointer/data to send to callback function
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* Argument2 - Pointer/data to send to callback function
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*
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* RETURNS:
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* Nothing
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*
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/*++
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* @name ExNotifyCallback
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* @implemented
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*/
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*
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* Calls a function pointer (a registered callback)
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* See: http://www.osronline.com/ddkx/kmarch/k102_2f5e.htm
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* http://msdn.microsoft.com/library/en-us/Kernel_d/hh/Kernel_d/Synchro_e954f515-e536-4e12-8419-e7e54c4a963b.xml.asp?frame=true
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* http://vmsone.com/~decuslib/vmssig/vmslt99b/nt/wdm-callback.txt
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*
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* @param CallbackObject
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* Which callback to call
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*
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* @param Argument1
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* Pointer/data to send to callback function
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*
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* @param Argument2
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* Pointer/data to send to callback function
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*
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* @return None
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*
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* @remarks None
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*
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*--*/
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VOID
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STDCALL
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ExNotifyCallback(
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IN PCALLBACK_OBJECT OpaqueCallbackObject,
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IN PVOID Argument1,
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IN PVOID Argument2
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)
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NTAPI
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ExNotifyCallback(IN PCALLBACK_OBJECT OpaqueCallbackObject,
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IN PVOID Argument1,
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IN PVOID Argument2)
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{
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PCALLBACK_OBJECT CallbackObject = (PCALLBACK_OBJECT)OpaqueCallbackObject;
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PLIST_ENTRY RegisteredCallbacks;
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PCALLBACK_REGISTRATION CallbackRegistration;
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KIRQL OldIrql;
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PCALLBACK_OBJECT CallbackObject = (PCALLBACK_OBJECT)OpaqueCallbackObject;
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PLIST_ENTRY RegisteredCallbacks;
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PCALLBACK_REGISTRATION CallbackRegistration;
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KIRQL OldIrql;
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/* Acquire the Lock */
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OldIrql = KfAcquireSpinLock(&CallbackObject->Lock);
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/* Acquire the Lock */
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OldIrql = KfAcquireSpinLock(&CallbackObject->Lock);
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|
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/* Enumerate through all the registered functions */
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for (RegisteredCallbacks = CallbackObject->RegisteredCallbacks.Flink;
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/* Enumerate through all the registered functions */
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for (RegisteredCallbacks = CallbackObject->RegisteredCallbacks.Flink;
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RegisteredCallbacks != &CallbackObject->RegisteredCallbacks;
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RegisteredCallbacks = RegisteredCallbacks->Flink)
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{
|
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{
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/* Get a pointer to a Callback Registration from the List Entries */
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CallbackRegistration = CONTAINING_RECORD(RegisteredCallbacks,
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CALLBACK_REGISTRATION,
|
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RegisteredCallbacks);
|
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|
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/* Get a pointer to a Callback Registration from the List Entries */
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CallbackRegistration = CONTAINING_RECORD ( RegisteredCallbacks,
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CALLBACK_REGISTRATION,
|
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RegisteredCallbacks);
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/* Don't bother doing Callback Notification if it's pending to be deleted */
|
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if (!CallbackRegistration->PendingDeletion)
|
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{
|
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/* Mark the Callback in use, so it won't get deleted while we are calling it */
|
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CallbackRegistration->InUse += 1;
|
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|
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/* Don't bother doing Callback Notification if it's pending to be deleted */
|
||||
if (!CallbackRegistration->PendingDeletion)
|
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{
|
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/* Release the Spinlock before making the call */
|
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KfReleaseSpinLock(&CallbackObject->Lock, OldIrql);
|
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|
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/* Mark the Callback in use, so it won't get deleted while we are calling it */
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CallbackRegistration->InUse += 1;
|
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/* Call the Registered Function */
|
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CallbackRegistration->CallbackFunction(
|
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CallbackRegistration->CallbackContext,
|
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Argument1,
|
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Argument2
|
||||
);
|
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|
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/* Release the Spinlock before making the call */
|
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KfReleaseSpinLock(&CallbackObject->Lock, OldIrql);
|
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/* Get SpinLock back */
|
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OldIrql = KfAcquireSpinLock(&CallbackObject->Lock);
|
||||
|
||||
/* Call the Registered Function */
|
||||
CallbackRegistration->CallbackFunction (
|
||||
CallbackRegistration->CallbackContext,
|
||||
Argument1,
|
||||
Argument2
|
||||
);
|
||||
/* We are not in use anymore */
|
||||
CallbackRegistration->InUse -= 1;
|
||||
|
||||
/* Get SpinLock back */
|
||||
OldIrql = KfAcquireSpinLock(&CallbackObject->Lock);
|
||||
|
||||
/* We are not in use anymore */
|
||||
CallbackRegistration->InUse -= 1;
|
||||
|
||||
/* If another instance of this function isn't running and deletion is pending, signal the event */
|
||||
if (CallbackRegistration->PendingDeletion && CallbackRegistration->InUse == 0)
|
||||
{
|
||||
KeSetEvent(&ExpCallbackEvent, 0, FALSE);
|
||||
}
|
||||
}
|
||||
}
|
||||
/* Unsynchronize and release the Callback Object */
|
||||
KfReleaseSpinLock(&CallbackObject->Lock, OldIrql);
|
||||
/* If another instance of this function isn't running and deletion is pending, signal the event */
|
||||
if (CallbackRegistration->PendingDeletion && CallbackRegistration->InUse == 0)
|
||||
{
|
||||
KeSetEvent(&ExpCallbackEvent, 0, FALSE);
|
||||
}
|
||||
}
|
||||
}
|
||||
/* Unsynchronize and release the Callback Object */
|
||||
KfReleaseSpinLock(&CallbackObject->Lock, OldIrql);
|
||||
}
|
||||
|
||||
/*
|
||||
* ExRegisterCallback
|
||||
*
|
||||
* FUNCTION:
|
||||
* Allows a function to associate a callback pointer (Function)
|
||||
* to a created Callback object
|
||||
*
|
||||
* ARGUMENTS:
|
||||
* CallbackObject = The Object Created with ExCreateCallBack
|
||||
* CallBackFunction = Pointer to the function to be called back
|
||||
* CallBackContext = Block of memory that can contain user-data
|
||||
* which will be passed on to the callback
|
||||
*
|
||||
* RETURNS:
|
||||
* A handle to a Callback Registration Structure (MSDN Documentation)
|
||||
*
|
||||
/*++
|
||||
* @name ExRegisterCallback
|
||||
* @implemented
|
||||
*/
|
||||
*
|
||||
* Allows a function to associate a callback pointer (Function) to
|
||||
* a created Callback object
|
||||
* See: DDK, OSR, links in ExNotifyCallback
|
||||
*
|
||||
* @param CallbackObject
|
||||
* The Object Created with ExCreateCallBack
|
||||
*
|
||||
* @param CallBackFunction
|
||||
* Pointer to the function to be called back
|
||||
*
|
||||
* @param CallBackContext
|
||||
* Block of memory that can contain user-data which will be
|
||||
* passed on to the callback
|
||||
*
|
||||
* @return A handle to a Callback Registration Structure (MSDN Documentation)
|
||||
*
|
||||
* @remarks None
|
||||
*
|
||||
*--*/
|
||||
PVOID
|
||||
STDCALL
|
||||
ExRegisterCallback(
|
||||
IN PCALLBACK_OBJECT OpaqueCallbackObject,
|
||||
IN PCALLBACK_FUNCTION CallbackFunction,
|
||||
IN PVOID CallbackContext
|
||||
)
|
||||
NTAPI
|
||||
ExRegisterCallback(IN PCALLBACK_OBJECT OpaqueCallbackObject,
|
||||
IN PCALLBACK_FUNCTION CallbackFunction,
|
||||
IN PVOID CallbackContext)
|
||||
{
|
||||
PCALLBACK_OBJECT CallbackObject = (PCALLBACK_OBJECT)OpaqueCallbackObject;
|
||||
PCALLBACK_REGISTRATION CallbackRegistration = NULL;
|
||||
KIRQL OldIrql;
|
||||
PCALLBACK_OBJECT CallbackObject = (PCALLBACK_OBJECT)OpaqueCallbackObject;
|
||||
PCALLBACK_REGISTRATION CallbackRegistration = NULL;
|
||||
KIRQL OldIrql;
|
||||
|
||||
PAGED_CODE();
|
||||
PAGED_CODE();
|
||||
|
||||
/* Create reference to Callback Object */
|
||||
ObReferenceObject (CallbackObject);
|
||||
/* Create reference to Callback Object */
|
||||
ObReferenceObject (CallbackObject);
|
||||
|
||||
/* Allocate memory for the structure */
|
||||
CallbackRegistration = ExAllocatePoolWithTag(
|
||||
NonPagedPool,
|
||||
sizeof(CallbackRegistration),
|
||||
CALLBACK_TAG
|
||||
);
|
||||
/* Fail if memory allocation failed */
|
||||
if(!CallbackRegistration)
|
||||
{
|
||||
ObDereferenceObject (CallbackObject);
|
||||
return NULL;
|
||||
}
|
||||
/* Allocate memory for the structure */
|
||||
CallbackRegistration = ExAllocatePoolWithTag(
|
||||
NonPagedPool,
|
||||
sizeof(CallbackRegistration),
|
||||
CALLBACK_TAG
|
||||
);
|
||||
/* Fail if memory allocation failed */
|
||||
if(!CallbackRegistration)
|
||||
{
|
||||
ObDereferenceObject (CallbackObject);
|
||||
return NULL;
|
||||
}
|
||||
|
||||
/* Create Callback Registration */
|
||||
CallbackRegistration->CallbackObject = CallbackObject; /* When unregistering, drivers send a handle to the Registration, not the object... */
|
||||
CallbackRegistration->CallbackFunction = CallbackFunction; /* NotifyCallback uses Objects, so this needs to be here in order to call the registered functions */
|
||||
CallbackRegistration->CallbackContext = CallbackContext; /* The documented NotifyCallback returns the Context, so we must save this somewhere */
|
||||
/* Create Callback Registration */
|
||||
CallbackRegistration->CallbackObject = CallbackObject; /* When unregistering, drivers send a handle to the Registration, not the object... */
|
||||
CallbackRegistration->CallbackFunction = CallbackFunction; /* NotifyCallback uses Objects, so this needs to be here in order to call the registered functions */
|
||||
CallbackRegistration->CallbackContext = CallbackContext; /* The documented NotifyCallback returns the Context, so we must save this somewhere */
|
||||
|
||||
/* Acquire SpinLock */
|
||||
OldIrql = KfAcquireSpinLock (&CallbackObject->Lock);
|
||||
/* Acquire SpinLock */
|
||||
OldIrql = KfAcquireSpinLock (&CallbackObject->Lock);
|
||||
|
||||
/* Add Callback if 1) No Callbacks registered or 2) Multiple Callbacks allowed */
|
||||
if(CallbackObject->AllowMultipleCallbacks || IsListEmpty(&CallbackObject->RegisteredCallbacks))
|
||||
{
|
||||
InsertTailList(&CallbackObject->RegisteredCallbacks,&CallbackRegistration->RegisteredCallbacks);
|
||||
}
|
||||
else
|
||||
{
|
||||
ExFreePool(CallbackRegistration);
|
||||
CallbackRegistration = NULL;
|
||||
}
|
||||
/* Add Callback if 1) No Callbacks registered or 2) Multiple Callbacks allowed */
|
||||
if(CallbackObject->AllowMultipleCallbacks || IsListEmpty(&CallbackObject->RegisteredCallbacks))
|
||||
{
|
||||
InsertTailList(&CallbackObject->RegisteredCallbacks,&CallbackRegistration->RegisteredCallbacks);
|
||||
}
|
||||
else
|
||||
{
|
||||
ExFreePool(CallbackRegistration);
|
||||
CallbackRegistration = NULL;
|
||||
}
|
||||
|
||||
/* Release SpinLock */
|
||||
KfReleaseSpinLock(&CallbackObject->Lock, OldIrql);
|
||||
/* Release SpinLock */
|
||||
KfReleaseSpinLock(&CallbackObject->Lock, OldIrql);
|
||||
|
||||
/* Return handle to Registration Object */
|
||||
return (PVOID) CallbackRegistration;
|
||||
/* Return handle to Registration Object */
|
||||
return (PVOID)CallbackRegistration;
|
||||
}
|
||||
|
||||
/*
|
||||
* ExUnregisterCallback
|
||||
*
|
||||
* FUNCTION:
|
||||
* Deregisters a CallBack
|
||||
*
|
||||
* ARGUMENTS:
|
||||
* CallbackRegistration = Callback Registration Handle
|
||||
*
|
||||
* RETURNS:
|
||||
* Nothing
|
||||
*
|
||||
/*++
|
||||
* @name ExUnregisterCallback
|
||||
* @implemented
|
||||
*/
|
||||
VOID STDCALL
|
||||
ExUnregisterCallback(
|
||||
IN PVOID CallbackRegistrationHandle
|
||||
)
|
||||
*
|
||||
* Deregisters a CallBack
|
||||
* See: DDK, OSR, links in ExNotifyCallback
|
||||
*
|
||||
* @param CallbackRegistration
|
||||
* Callback Registration Handle
|
||||
*
|
||||
* @return None
|
||||
*
|
||||
* @remarks None
|
||||
*
|
||||
*--*/
|
||||
VOID
|
||||
NTAPI
|
||||
ExUnregisterCallback(IN PVOID CallbackRegistrationHandle)
|
||||
{
|
||||
PCALLBACK_REGISTRATION CallbackRegistration;
|
||||
PCALLBACK_OBJECT CallbackObject;
|
||||
KIRQL OldIrql;
|
||||
PCALLBACK_REGISTRATION CallbackRegistration;
|
||||
PCALLBACK_OBJECT CallbackObject;
|
||||
KIRQL OldIrql;
|
||||
|
||||
PAGED_CODE();
|
||||
PAGED_CODE();
|
||||
|
||||
/* Convert Handle to valid Structure Pointer */
|
||||
CallbackRegistration = (PCALLBACK_REGISTRATION) CallbackRegistrationHandle;
|
||||
/* Convert Handle to valid Structure Pointer */
|
||||
CallbackRegistration = (PCALLBACK_REGISTRATION) CallbackRegistrationHandle;
|
||||
|
||||
/* Get the Callback Object */
|
||||
CallbackObject = CallbackRegistration->CallbackObject;
|
||||
/* Get the Callback Object */
|
||||
CallbackObject = CallbackRegistration->CallbackObject;
|
||||
|
||||
/* Lock the Object */
|
||||
OldIrql = KfAcquireSpinLock (&CallbackObject->Lock);
|
||||
/* Lock the Object */
|
||||
OldIrql = KfAcquireSpinLock (&CallbackObject->Lock);
|
||||
|
||||
/* We can't Delete the Callback if it's in use, because this would create a call towards a null pointer => crash */
|
||||
while (CallbackRegistration->InUse)
|
||||
{
|
||||
/* We can't Delete the Callback if it's in use, because this would create a call towards a null pointer => crash */
|
||||
while (CallbackRegistration->InUse)
|
||||
{
|
||||
/* Similarly, we also don't want to wait ages for all pending callbacks to be called */
|
||||
CallbackRegistration->PendingDeletion = TRUE;
|
||||
|
||||
/* Similarly, we also don't want to wait ages for all pending callbacks to be called */
|
||||
CallbackRegistration->PendingDeletion = TRUE;
|
||||
/* We are going to wait for the event, so the Lock isn't necessary */
|
||||
KfReleaseSpinLock (&CallbackObject->Lock, OldIrql);
|
||||
|
||||
/* We are going to wait for the event, so the Lock isn't necessary */
|
||||
KfReleaseSpinLock (&CallbackObject->Lock, OldIrql);
|
||||
/* Make sure the event is cleared */
|
||||
KeClearEvent (&ExpCallbackEvent);
|
||||
|
||||
/* Make sure the event is cleared */
|
||||
KeClearEvent (&ExpCallbackEvent);
|
||||
/* Wait for the Event */
|
||||
KeWaitForSingleObject (
|
||||
&ExpCallbackEvent,
|
||||
Executive,
|
||||
KernelMode,
|
||||
FALSE,
|
||||
NULL
|
||||
);
|
||||
|
||||
/* Wait for the Event */
|
||||
KeWaitForSingleObject (
|
||||
&ExpCallbackEvent,
|
||||
Executive,
|
||||
KernelMode,
|
||||
FALSE,
|
||||
NULL
|
||||
);
|
||||
/* We need the Lock again */
|
||||
OldIrql = KfAcquireSpinLock(&CallbackObject->Lock);
|
||||
}
|
||||
|
||||
/* We need the Lock again */
|
||||
OldIrql = KfAcquireSpinLock(&CallbackObject->Lock);
|
||||
}
|
||||
/* Remove the Callback */
|
||||
RemoveEntryList(&CallbackRegistration->RegisteredCallbacks);
|
||||
|
||||
/* Remove the Callback */
|
||||
RemoveEntryList(&CallbackRegistration->RegisteredCallbacks);
|
||||
/* It's now safe to release the lock */
|
||||
KfReleaseSpinLock(&CallbackObject->Lock, OldIrql);
|
||||
|
||||
/* It's now safe to release the lock */
|
||||
KfReleaseSpinLock(&CallbackObject->Lock, OldIrql);
|
||||
/* Delete this registration */
|
||||
ExFreePool(CallbackRegistration);
|
||||
|
||||
/* Delete this registration */
|
||||
ExFreePool(CallbackRegistration);
|
||||
|
||||
/* Remove the reference */
|
||||
ObDereferenceObject(CallbackObject);
|
||||
/* Remove the reference */
|
||||
ObDereferenceObject(CallbackObject);
|
||||
}
|
||||
|
||||
/* EOF */
|
||||
|
|
|
|||
Loading…
Reference in a new issue