1 /* 2 * Copyright (C) 2018 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package com.android.server.input; 18 19 import android.text.TextUtils; 20 import android.util.Pair; 21 import android.util.Slog; 22 import android.util.Xml; 23 24 import com.android.internal.annotations.VisibleForTesting; 25 import com.android.internal.util.XmlUtils; 26 27 import org.xmlpull.v1.XmlPullParser; 28 29 import java.io.InputStream; 30 import java.io.InputStreamReader; 31 import java.util.ArrayList; 32 import java.util.List; 33 34 35 class ConfigurationProcessor { 36 private static final String TAG = "ConfigurationProcessor"; 37 processExcludedDeviceNames(InputStream xml)38 static List<String> processExcludedDeviceNames(InputStream xml) throws Exception { 39 List<String> names = new ArrayList<>(); 40 try (InputStreamReader confReader = new InputStreamReader(xml)) { 41 XmlPullParser parser = Xml.newPullParser(); 42 parser.setInput(confReader); 43 XmlUtils.beginDocument(parser, "devices"); 44 while (true) { 45 XmlUtils.nextElement(parser); 46 if (!"device".equals(parser.getName())) { 47 break; 48 } 49 String name = parser.getAttributeValue(null, "name"); 50 if (name != null) { 51 names.add(name); 52 } 53 } 54 } 55 return names; 56 } 57 58 /** 59 * Parse the configuration for input port associations. 60 * 61 * Configuration format: 62 * <code> 63 * <ports> 64 * <port display="0" input="usb-xhci-hcd.0.auto-1.4.3/input0" /> 65 * <port display="1" input="usb-xhci-hcd.0.auto-1.4.2/input0" /> 66 * </ports> 67 * </code> 68 * 69 * In this example, any input device that has physical port of 70 * "usb-xhci-hcd.0.auto-1.4.3/input0" will be associated with a display 71 * that has the physical port "0". If such a display does not exist, the input device 72 * will be disabled and no input events will be dispatched from that input device until a 73 * matching display appears. Likewise, an input device that has port "..1.4.2.." will have 74 * its input events forwarded to a display that has physical port of "1". 75 * 76 * Note: display port must be a numeric value, and this is checked at runtime for validity. 77 * At the same time, it is specified as a string for simplicity. 78 * 79 * Note: do not confuse "display id" with "display port". 80 * The "display port" is the physical port on which the display is connected. This could 81 * be something like HDMI0, HDMI1, etc. For virtual displays, "display port" will be null. 82 * The "display id" is a way to identify a particular display, and is not a stable API. 83 * All displays, including virtual ones, will have a display id. 84 * 85 * Return the pairs of associations. The first item in the pair is the input port, 86 * the second item in the pair is the display port. 87 */ 88 @VisibleForTesting processInputPortAssociations(InputStream xml)89 static List<Pair<String, String>> processInputPortAssociations(InputStream xml) 90 throws Exception { 91 List<Pair<String, String>> associations = new ArrayList<>(); 92 try (InputStreamReader confReader = new InputStreamReader(xml)) { 93 XmlPullParser parser = Xml.newPullParser(); 94 parser.setInput(confReader); 95 XmlUtils.beginDocument(parser, "ports"); 96 97 while (true) { 98 XmlUtils.nextElement(parser); 99 String entryName = parser.getName(); 100 if (!"port".equals(entryName)) { 101 break; 102 } 103 String inputPort = parser.getAttributeValue(null, "input"); 104 String displayPort = parser.getAttributeValue(null, "display"); 105 if (TextUtils.isEmpty(inputPort) || TextUtils.isEmpty(displayPort)) { 106 // This is likely an error by an OEM during device configuration 107 Slog.wtf(TAG, "Ignoring incomplete entry"); 108 continue; 109 } 110 try { 111 Integer.parseUnsignedInt(displayPort); 112 } catch (NumberFormatException e) { 113 Slog.wtf(TAG, "Display port should be an integer"); 114 continue; 115 } 116 associations.add(new Pair<>(inputPort, displayPort)); 117 } 118 } 119 return associations; 120 } 121 } 122