/* * Copyright (c) 1998-2000 Apple Computer, Inc. All rights reserved. * * @APPLE_LICENSE_HEADER_START@ * * The contents of this file constitute Original Code as defined in and * are subject to the Apple Public Source License Version 1.1 (the * "License"). You may not use this file except in compliance with the * License. Please obtain a copy of the License at * http://www.apple.com/publicsource and read it before using this file. * * This Original Code and all software distributed under the License are * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT. Please see the * License for the specific language governing rights and limitations * under the License. * * @APPLE_LICENSE_HEADER_END@ */ /* File: HIDHasUsage.c Contains: xxx put contents here xxx Version: xxx put version here xxx Copyright: © 1999-2000 by Apple Computer, Inc., all rights reserved. File Ownership: DRI: xxx put dri here xxx Other Contact: xxx put other contact here xxx Technology: xxx put technology here xxx Writers: (KH) Keithen Hayenga (BWS) Brent Schorsch Change History (most recent first): <USB2> 12/12/00 KH range count off by 1. <USB1> 3/5/99 BWS first checked in */ #include "HIDLib.h" /* *------------------------------------------------------------------------------ * * HidP_UsageFromIndex * * Input: * ptPreparsedData - The Preparsed Data * ptReportItem - The Report Item * usagePage - The usage Page to find * usage - The usage to find * piIndex(optional) - The usage Index pointer (Can be used to tell * which bits in an array correspond to that usage.) * piCount(optional) - The usage Count pointer (Can be used to tell * how many items will be in a report.) * Output: * piIndex - The usage Index * Returns: * The usage * *------------------------------------------------------------------------------ */ Boolean HIDHasUsage (HIDPreparsedDataRef preparsedDataRef, HIDReportItem *ptReportItem, HIDUsage usagePage, HIDUsage usage, UInt32 *piIndex, UInt32 *piCount) { HIDPreparsedDataPtr ptPreparsedData = (HIDPreparsedDataPtr) preparsedDataRef; int iUsageItem; UInt32 iUsageIndex; int iUsages; int i; SInt32 iCountsLeft; HIDP_UsageItem *ptUsageItem; Boolean bOnPage; /* * Disallow Null Pointers */ if ((ptPreparsedData == NULL) || (ptReportItem == NULL)) return 0; if (ptPreparsedData->hidTypeIfValid != kHIDOSType) return 0; /* * Look through the usage Items for this usage */ iUsageItem = ptReportItem->firstUsageItem; iUsageIndex = 0; for (i=0; i<ptReportItem->usageItemCount; i++) { /* * Each usage Item is either a usage or a usage range */ ptUsageItem = &ptPreparsedData->usageItems[iUsageItem++]; bOnPage = ((usagePage == 0) || (usagePage == ptUsageItem->usagePage)); if (ptUsageItem->isRange) { /* * For usage Ranges * If the index is in the range * then return the usage * Otherwise adjust the index by the size of the range */ if ((usage >= ptUsageItem->usageMinimum) && (usage <= ptUsageItem->usageMaximum)) { if (piIndex != NULL) *piIndex = iUsageIndex + (ptUsageItem->usageMinimum - usage); /* * If this usage is the last one for this ReportItem * then it gets all of the remaining reportCount */ if (piCount != NULL) { // piCount is going to be used to find which element in a button array is // the one that returns the value for that usage. if (((i+1) == ptReportItem->usageItemCount) && (usage == ptUsageItem->usageMaximum)) { // Hmm, the same logic in the non-range case below was wrong. But things // seem to be working for finding buttons, so i am not changing it here. // However, we have made some changes to range calculations that may no // longer require that -1 here either. Heads up! iCountsLeft = ptReportItem->globals.reportCount - iUsageIndex - 1; if (iCountsLeft > 1) *piCount = iCountsLeft; else *piCount = 1; } else *piCount = 1; } if (bOnPage) return true; } iUsages = ptUsageItem->usageMaximum - ptUsageItem->usageMinimum; if (iUsages < 0) iUsages = -iUsages; iUsages++; // Add off by one adjustment AFTER sign correction. iUsageIndex += iUsages; } else { /* * For Usages * If the index is zero * then return this usage * Otherwise one less to index through */ if (usage == ptUsageItem->usage) { if (piIndex != NULL) *piIndex = iUsageIndex; if (piCount != NULL) { if ((i+1) == ptReportItem->usageItemCount) { // Keithen does not understand the logic of iCountsLeft. // In Radar #2579612 we come through here for HIDGetUsageValueArray // and HIDGetSpecificValueCaps. In both cases piCount that is returned // should be the reportCount without the -1. // iCountsLeft = ptReportItem->globals.reportCount - iUsageIndex - 1; iCountsLeft = ptReportItem->globals.reportCount - iUsageIndex; if (iCountsLeft > 1) *piCount = iCountsLeft; else *piCount = 1; } else *piCount = 1; } if (bOnPage) return true; } iUsageIndex++; } } return false; }