iokit/Families/IOHIDSystem/IOHIDDescriptorParser/HIDGetCollectionNodes.c

   1 /*
   2  * Copyright (c) 1998-2000 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * The contents of this file constitute Original Code as defined in and
   7  * are subject to the Apple Public Source License Version 1.1 (the
   8  * "License").  You may not use this file except in compliance with the
   9  * License.  Please obtain a copy of the License at
  10  * http://www.apple.com/publicsource and read it before using this file.
  11  *
  12  * This Original Code and all software distributed under the License are
  13  * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  14  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  15  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  16  * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
  17  * License for the specific language governing rights and limitations
  18  * under the License.
  19  *
  20  * @APPLE_LICENSE_HEADER_END@
  21  */
  22 /*
  23         File:           HIDGetCollectionNodes.c
  24
  25         Contains:       xxx put contents here xxx
  26
  27         Version:        xxx put version here xxx
  28
  29         Copyright:      © 1999 by Apple Computer, Inc., all rights reserved.
  30
  31         File Ownership:
  32
  33                 DRI:                            xxx put dri here xxx
  34
  35                 Other Contact:          xxx put other contact here xxx
  36
  37                 Technology:                     xxx put technology here xxx
  38
  39         Writers:
  40
  41                 (BWS)   Brent Schorsch
  42
  43         Change History (most recent first):
  44
  45           <USB1>          3/5/99        BWS             first checked in
  46 */
  47
  48 #include "HIDLib.h"
  49
  50 /*
  51  *------------------------------------------------------------------------------
  52  *
  53  * HIDGetCollectionNodes - Get the Collections Database
  54  *
  55  *       Input:
  56  *                        ptLinkCollectionNodes           - Node Array provided by caller
  57  *                        piLinkCollectionNodesLength - Maximum Nodes
  58  *       Output:
  59  *                        piLinkCollectionNodesLength - Actual number of Nodes
  60  *       Returns:
  61  *                        kHIDSuccess             - Success
  62  *                        kHIDNullPointerErr     - Argument, Pointer was Null
  63  *                        HidP_NotEnoughRoom   - More Nodes than space for them
  64  *
  65  *------------------------------------------------------------------------------
  66 */
  67 OSStatus HIDGetCollectionNodes(HIDCollectionNodePtr ptLinkCollectionNodes,
  68                                                                                 UInt32 *piLinkCollectionNodesLength,
  69                                                                                 HIDPreparsedDataRef preparsedDataRef)
  70 {
  71         HIDPreparsedDataPtr ptPreparsedData = (HIDPreparsedDataPtr) preparsedDataRef;
  72         HIDCollectionNodePtr ptLink;
  73         HIDCollection *ptCollection;
  74         HIDP_UsageItem *ptFirstUsageItem;
  75         int iMaxNodes;
  76         int collectionCount;
  77         int firstUsageItem;
  78         int i;
  79 /*
  80  *      Disallow Null Pointers
  81 */
  82         if ((ptLinkCollectionNodes == NULL)
  83          || (piLinkCollectionNodesLength == NULL)
  84          || (ptPreparsedData == NULL))
  85                 return kHIDNullPointerErr;
  86         if (ptPreparsedData->hidTypeIfValid != kHIDOSType)
  87                 return kHIDInvalidPreparsedDataErr;
  88 /*
  89  *      Remember the size of the output array
  90 */
  91         iMaxNodes = *piLinkCollectionNodesLength;
  92         collectionCount = ptPreparsedData->collectionCount;
  93         *piLinkCollectionNodesLength = collectionCount;
  94 /*
  95  *      Report if there's not enough room
  96 */
  97         if (collectionCount > iMaxNodes)
  98                 return kHIDBufferTooSmallErr;
  99 /*
 100  *      Copy the nodes
 101 */
 102         for (i=0; i<collectionCount; i++)
 103         {
 104                 ptCollection = &ptPreparsedData->collections[i];
 105                 ptLink = &ptLinkCollectionNodes[i];
 106                 firstUsageItem = ptCollection->firstUsageItem;
 107                 ptFirstUsageItem = &ptPreparsedData->usageItems[firstUsageItem];
 108                 ptLink->collectionUsage = ptFirstUsageItem->usage;
 109                 ptLink->collectionUsagePage = ptCollection->usagePage;
 110                 ptLink->parent = ptCollection->parent;
 111                 ptLink->numberOfChildren = ptCollection->children;
 112                 ptLink->nextSibling = ptCollection->nextSibling;
 113                 ptLink->firstChild = ptCollection->firstChild;
 114         }
 115 /*
 116  *      Report if there wasn't enough space
 117 */
 118         if (iMaxNodes < ptPreparsedData->collectionCount)
 119                 return kHIDBufferTooSmallErr;
 120         return kHIDSuccess;
 121 }