RtlLookupElementGenericTableAvl routine

The RtlLookupElementGenericTableAvl routine searches a generic table for an element that matches the specified data.

Syntax


PVOID RtlLookupElementGenericTableAvl(
  _In_ PRTL_AVL_TABLE Table,
  _In_ PVOID          Buffer
);

Parameters

Table [in]

Pointer to the generic Adelson-Velsky/Landis (AVL) table (RTL_AVL_TABLE). The table must have been initialized by calling RtlInitializeGenericTableAvl.

Buffer [in]

A buffer of search data to pass to the CompareRoutine that was registered when RtlInitializeGenericTableAvl initialized the generic table. For more information, see the description of RtlInitializeGenericTableAvl.

Return value

RtlLookupElementGenericTableAvl returns a pointer to the user data that is associated with the matching element in the generic table, or NULL if the generic table currently has no elements or if no matching element is found.

Remarks

By default, the operating system uses splay trees to implement generic tables, but the RtlLookupElementGenericTableAvl routine only works with Adelson-Velsky/Landis (AVL) trees. To configure the generic table routines to use AVL trees instead of splay trees in your driver, insert the following define statement in a common header file before including Ntddk.h:

#define RTL_USE_AVL_TABLES 0

If RTL_USE_AVL_TABLES is not defined, you must use the AVL form of the generic table routines. For example, use the RtlLookupElementGenericTableAvl routine instead of RtlLookupElementGenericTable. In the call to RtlLookupElementGenericTableAvl, the caller must pass a RTL_AVL_TABLE table structure rather than RTL_GENERIC_TABLE.

Callers of the Rtl..GenericTableAvl routines are responsible for exclusively synchronizing access to the generic table. An exclusive fast mutex is the most efficient synchronization mechanism to use for this purpose.

Callers of RtlLookupElementGenericTableAvl must be running at IRQL < DISPATCH_LEVEL if either of the following conditions holds:

  • The caller-allocated memory at Table or at Buffer is pageable.

  • The caller-supplied CompareRoutine contains pageable code.

Requirements

Target platform

Universal

Version

Available starting with Windows XP.

Header

Ntddk.h (include Ntddk.h or Ntifs.h)

Library

NtosKrnl.lib

DLL

NtosKrnl.exe

IRQL

< DISPATCH_LEVEL (see Remarks section)

See also

RtlInitializeGenericTableAvl
RtlIsGenericTableEmptyAvl
RtlNumberGenericTableElementsAvl

 

 

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