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/*++
Copyright (c) 1999 - 2002 Microsoft Corporation
Module Name:
CtxProc.h
Abstract:
This is the header file defining the functions of the kernel mode
filter driver implementing the context sample.
Environment:
Kernel mode
--*/
//
// Functions implemented in operations.c
//
FLT_PREOP_CALLBACK_STATUS
CtxPreCreate (
_Inout_ PFLT_CALLBACK_DATA Cbd,
_In_ PCFLT_RELATED_OBJECTS FltObjects,
_Flt_CompletionContext_Outptr_ PVOID *CompletionContext
);
FLT_POSTOP_CALLBACK_STATUS
CtxPostCreate (
_Inout_ PFLT_CALLBACK_DATA Cbd,
_In_ PCFLT_RELATED_OBJECTS FltObjects,
_Inout_opt_ PVOID CbdContext,
_In_ FLT_POST_OPERATION_FLAGS Flags
);
FLT_PREOP_CALLBACK_STATUS
CtxPreCleanup (
_Inout_ PFLT_CALLBACK_DATA Cbd,
_In_ PCFLT_RELATED_OBJECTS FltObjects,
_Flt_CompletionContext_Outptr_ PVOID *CompletionContext
);
FLT_PREOP_CALLBACK_STATUS
CtxPreClose (
_Inout_ PFLT_CALLBACK_DATA Cbd,
_In_ PCFLT_RELATED_OBJECTS FltObjects,
_Flt_CompletionContext_Outptr_ PVOID *CompletionContext
);
FLT_PREOP_CALLBACK_STATUS
CtxPreSetInfo (
_Inout_ PFLT_CALLBACK_DATA Cbd,
_In_ PCFLT_RELATED_OBJECTS FltObjects,
_Flt_CompletionContext_Outptr_ PVOID *CompletionContext
);
FLT_POSTOP_CALLBACK_STATUS
CtxPostSetInfo (
_Inout_ PFLT_CALLBACK_DATA Cbd,
_In_ PCFLT_RELATED_OBJECTS FltObjects,
_Inout_opt_ PVOID CbdContext,
_In_ FLT_POST_OPERATION_FLAGS Flags
);
//
// Functions implemented in context.c
//
NTSTATUS
CtxFindOrCreateFileContext (
_In_ PFLT_CALLBACK_DATA Cbd,
_In_ BOOLEAN CreateIfNotFound,
_When_( CreateIfNotFound != FALSE, _In_ ) _When_( CreateIfNotFound == FALSE, _In_opt_ ) PUNICODE_STRING FileName,
_Outptr_ PCTX_FILE_CONTEXT *StreamContext,
_Out_opt_ PBOOLEAN ContextCreated
);
NTSTATUS
CtxCreateFileContext (
_In_ PUNICODE_STRING FileName,
_Outptr_ PCTX_FILE_CONTEXT *StreamContext
);
NTSTATUS
CtxFindOrCreateStreamContext (
_In_ PFLT_CALLBACK_DATA Cbd,
_In_ BOOLEAN CreateIfNotFound,
_Outptr_ PCTX_STREAM_CONTEXT *StreamContext,
_Out_opt_ PBOOLEAN ContextCreated
);
NTSTATUS
CtxCreateStreamContext (
_Outptr_ PCTX_STREAM_CONTEXT *StreamContext
);
NTSTATUS
CtxUpdateNameInStreamContext (
_In_ PUNICODE_STRING DirectoryName,
_Inout_ PCTX_STREAM_CONTEXT StreamContext
);
NTSTATUS
CtxCreateOrReplaceStreamHandleContext (
_In_ PFLT_CALLBACK_DATA Cbd,
_In_ BOOLEAN ReplaceIfExists,
_Outptr_ PCTX_STREAMHANDLE_CONTEXT *StreamHandleContext,
_Out_opt_ PBOOLEAN ContextReplaced
);
NTSTATUS
CtxCreateStreamHandleContext (
_Outptr_ PCTX_STREAMHANDLE_CONTEXT *StreamHandleContext
);
NTSTATUS
CtxUpdateNameInStreamHandleContext (
_In_ PUNICODE_STRING DirectoryName,
_Inout_ PCTX_STREAMHANDLE_CONTEXT StreamHandleContext
);
//
// Functions implemented in support.c
//
_At_(String->Length, _Out_range_(==, 0))
_At_(String->MaximumLength, _In_)
_At_(String->Buffer, _Pre_maybenull_ _Post_notnull_ _Post_writable_byte_size_(String->MaximumLength))
NTSTATUS
CtxAllocateUnicodeString (
_Out_ PUNICODE_STRING String
);
_At_(String->Length, _Out_range_(==, 0))
_At_(String->MaximumLength, _Out_range_(==, 0))
_At_(String->Buffer, _Pre_notnull_ _Post_null_)
VOID
CtxFreeUnicodeString (
_Pre_notnull_ PUNICODE_STRING String
);
//
// Resource support
//
FORCEINLINE
PERESOURCE
CtxAllocateResource (
VOID
)
{
return ExAllocatePoolZero( NonPagedPool,
sizeof( ERESOURCE ),
CTX_RESOURCE_TAG );
}
FORCEINLINE
VOID
CtxFreeResource (
_In_ PERESOURCE Resource
)
{
ExFreePoolWithTag( Resource,
CTX_RESOURCE_TAG );
}
FORCEINLINE
VOID
_Acquires_lock_(_Global_critical_region_)
_IRQL_requires_max_(APC_LEVEL)
CtxAcquireResourceExclusive (
_Inout_ _Requires_lock_not_held_(*_Curr_) _Acquires_exclusive_lock_(*_Curr_)
PERESOURCE Resource
)
{
FLT_ASSERT(KeGetCurrentIrql() <= APC_LEVEL);
FLT_ASSERT(ExIsResourceAcquiredExclusiveLite(Resource) ||
!ExIsResourceAcquiredSharedLite(Resource));
KeEnterCriticalRegion();
(VOID)ExAcquireResourceExclusiveLite( Resource, TRUE );
}
FORCEINLINE
VOID
_Acquires_lock_(_Global_critical_region_)
_IRQL_requires_max_(APC_LEVEL)
CtxAcquireResourceShared (
_Inout_ _Requires_lock_not_held_(*_Curr_) _Acquires_shared_lock_(*_Curr_)
PERESOURCE Resource
)
{
FLT_ASSERT(KeGetCurrentIrql() <= APC_LEVEL);
KeEnterCriticalRegion();
(VOID)ExAcquireResourceSharedLite( Resource, TRUE );
}
FORCEINLINE
VOID
_Releases_lock_(_Global_critical_region_)
_Requires_lock_held_(_Global_critical_region_)
_IRQL_requires_max_(APC_LEVEL)
CtxReleaseResource (
_Inout_ _Requires_lock_held_(*_Curr_) _Releases_lock_(*_Curr_)
PERESOURCE Resource
)
{
FLT_ASSERT(KeGetCurrentIrql() <= APC_LEVEL);
FLT_ASSERT(ExIsResourceAcquiredExclusiveLite(Resource) ||
ExIsResourceAcquiredSharedLite(Resource));
ExReleaseResourceLite(Resource);
KeLeaveCriticalRegion();
}
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