VALUE_SEARCH_RETURN_TYPE NTAPI CmpCompareNewValueDataAgainstKCBCache	(	IN PCM_KEY_CONTROL_BLOCK	Kcb,
		IN PUNICODE_STRING	ValueName,
		IN ULONG	Type,
		IN PVOID	Data,
		IN ULONG	DataSize
	)
Definition at line 676 of file cmvalche.c.
Referenced by CmSetValueKey().
{
    VALUE_SEARCH_RETURN_TYPE SearchResult;
    PCM_KEY_NODE KeyNode;
    PCM_CACHED_VALUE *CachedValue;
    ULONG Index;
    PCM_KEY_VALUE Value;
    BOOLEAN ValueCached, BufferAllocated = FALSE;
    PVOID Buffer;
    HCELL_INDEX ValueCellToRelease = HCELL_NIL, CellToRelease = HCELL_NIL;
    BOOLEAN IsSmall;
    ULONG_PTR CompareResult;
    PAGED_CODE();

    /* Check if this is a symlink */
    if (Kcb->Flags & KEY_SYM_LINK)
    {
        /* We need the exclusive lock */
        if (!(CmpIsKcbLockedExclusive(Kcb)) &&
            !(CmpTryToConvertKcbSharedToExclusive(Kcb)))
        {
            /* We need the exclusive lock */
            return SearchNeedExclusiveLock;
        }
        
        /* Otherwise, get the key node */
        KeyNode = (PCM_KEY_NODE)HvGetCell(Kcb->KeyHive, Kcb->KeyCell);
        if (!KeyNode) return SearchFail;
        
        /* Cleanup the KCB cache */
        CmpCleanUpKcbValueCache(Kcb);
        
        /* Sanity checks */
        ASSERT(!(CMP_IS_CELL_CACHED(Kcb->ValueCache.ValueList)));
        ASSERT(!(Kcb->ExtFlags & CM_KCB_SYM_LINK_FOUND));
        
        /* Set the value cache */
        Kcb->ValueCache.Count = KeyNode->ValueList.Count;
        Kcb->ValueCache.ValueList = KeyNode->ValueList.List;
        
        /* Release the cell */
        HvReleaseCell(Kcb->KeyHive, Kcb->KeyCell);
    }
    
    /* Do the search */
    SearchResult = CmpFindValueByNameFromCache(Kcb,
                                               ValueName,
                                               &CachedValue,
                                               &Index,
                                               &Value,
                                               &ValueCached,
                                               &ValueCellToRelease);
    if (SearchResult == SearchNeedExclusiveLock)
    {
        /* We need the exclusive lock */
        ASSERT(!CmpIsKcbLockedExclusive(Kcb));
        ASSERT(ValueCellToRelease == HCELL_NIL);
        ASSERT(Value == NULL);
        goto Quickie;
    }
    else if (SearchResult == SearchSuccess)
    {
        /* Sanity check */
        ASSERT(Value);
        
        /* First of all, check if the key size and type matches */
        if ((Type == Value->Type) &&
            (DataSize == (Value->DataLength & ~CM_KEY_VALUE_SPECIAL_SIZE)))
        {
            /* Check if this is a small key */
            IsSmall = (DataSize <= CM_KEY_VALUE_SMALL) ? TRUE: FALSE;
            if (IsSmall)
            {
                /* Compare against the data directly */
                Buffer = &Value->Data;
            }
            else
            {
                /* Do a search */
                SearchResult = CmpGetValueDataFromCache(Kcb,
                                                        CachedValue,
                                                        (PCELL_DATA)Value,
                                                        ValueCached,
                                                        &Buffer,
                                                        &BufferAllocated,
                                                        &CellToRelease);
                if (SearchResult != SearchSuccess)
                {
                    /* Sanity checks */
                    ASSERT(Buffer == NULL);
                    ASSERT(BufferAllocated == FALSE);
                    goto Quickie;
                }
            }
            
            /* Now check the data size */
            if (DataSize)
            {
                /* Do the compare */
                CompareResult = RtlCompareMemory(Buffer,
                                                 Data,
                                                 DataSize &
                                                 ~CM_KEY_VALUE_SPECIAL_SIZE);
            }
            else
            {
                /* It's equal */
                CompareResult = 0;
            }
            
            /* Now check if the compare wasn't equal */
            if (CompareResult != DataSize) SearchResult = SearchFail;
        }
        else
        {
            /* The length or type isn't equal */
            SearchResult = SearchFail;
        }
    }

Quickie:
    /* Release the value cell */
    if (ValueCellToRelease) HvReleaseCell(Kcb->KeyHive, ValueCellToRelease);
    
    /* Free the buffer */
    if (BufferAllocated) CmpFree(Buffer, 0);
    
    /* Free the cell */
    if (CellToRelease) HvReleaseCell(Kcb->KeyHive, CellToRelease);

    /* Return the search result */
    return SearchResult;
}
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