/* * Copyright (c) 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: HIDGetReportLength.c */ #include "HIDLib.h" /* *------------------------------------------------------------------------------ * * HIDGetReportLength - Get the length of a report * * Input: * reportType - HIDP_Input, HIDP_Output, HIDP_Feature * reportID - Desired Report * preparsedDataRef - opaque Pre-Parsed Data * Output: * reportLength - The length of the Report * Returns: * status kHIDNullPointerErr, kHIDInvalidPreparsedDataErr, * kHIDUsageNotFoundErr * *------------------------------------------------------------------------------ */ OSStatus HIDGetReportLength(HIDReportType reportType, UInt8 reportID, ByteCount * reportLength, HIDPreparsedDataRef preparsedDataRef) { HIDPreparsedDataPtr ptPreparsedData = (HIDPreparsedDataPtr)preparsedDataRef; ByteCount dataLength = 0; OSStatus iStatus = kHIDUsageNotFoundErr; int iR; // Disallow Null Pointers. if (ptPreparsedData == NULL || reportLength == NULL) return kHIDNullPointerErr; if (ptPreparsedData->hidTypeIfValid != kHIDOSType) return kHIDInvalidPreparsedDataErr; // Go through the Reports. for (iR = 0; iR < ptPreparsedData->reportCount; iR++) { if (ptPreparsedData->reports[iR].reportID == reportID) { switch(reportType) { case kHIDInputReport: dataLength = (ptPreparsedData->reports[iR].inputBitCount + 7)/8; break; case kHIDOutputReport: dataLength = (ptPreparsedData->reports[iR].outputBitCount + 7)/8; break; case kHIDFeatureReport: dataLength = (ptPreparsedData->reports[iR].featureBitCount + 7)/8; break; default: return kHIDInvalidReportTypeErr; } break; } } // If the reportID > 0, there must be 1 byte for reportID, so total report must be > 1. // (Would come into play if we had input report 3, but searched for ouput report 3 // that didn't exist.) if ((reportID == 0) && (dataLength > 0) || dataLength > 1) { iStatus = noErr; } else { dataLength = 0; // Ignore report that had id, but no data. } *reportLength = dataLength; return iStatus; }