uinput: support evemu recordings (4ec6969f) · Commits · e / os / android_frameworks_base

cmds/uinput/src/com/android/commands/uinput/EvemuParser.java

0 → 100644

+380 −0

Original line number	Diff line number	Diff line
		/*
		* Copyright 2023 The Android Open Source Project
		*
		* Licensed under the Apache License, Version 2.0 (the "License");
		* you may not use this file except in compliance with the License.
		* You may obtain a copy of the License at
		*
		* http://www.apache.org/licenses/LICENSE-2.0
		*
		* Unless required by applicable law or agreed to in writing, software
		* distributed under the License is distributed on an "AS IS" BASIS,
		* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
		* See the License for the specific language governing permissions and
		* limitations under the License.
		*/

		package com.android.commands.uinput;

		import android.annotation.Nullable;
		import android.util.SparseArray;

		import java.io.BufferedReader;
		import java.io.IOException;
		import java.io.Reader;
		import java.util.ArrayDeque;
		import java.util.ArrayList;
		import java.util.Arrays;
		import java.util.HashMap;
		import java.util.List;
		import java.util.Map;
		import java.util.Queue;

		import src.com.android.commands.uinput.InputAbsInfo;

		/**
		* Parser for the <a href="https://gitlab.freedesktop.org/libevdev/evemu">FreeDesktop evemu</a>
		* event recording format.
		*/
		public class EvemuParser implements EventParser {
		private static final String TAG = "UinputEvemuParser";

		/**
		* The device ID to use for all events. Since evemu files only support single-device
		* recordings, this will always be the same.
		*/
		private static final int DEVICE_ID = 1;
		private static final int REGISTRATION_DELAY_MILLIS = 500;

		private static class CommentAwareReader {
		private final BufferedReader mReader;
		private String mNextLine;

		CommentAwareReader(BufferedReader in) throws IOException {
		mReader = in;
		mNextLine = findNextLine();
		}

		private @Nullable String findNextLine() throws IOException {
		String line = "";
		while (line != null && line.length() == 0) {
		String unstrippedLine = mReader.readLine();
		if (unstrippedLine == null) {
		// End of file.
		return null;
		}
		line = stripComments(unstrippedLine);
		}
		return line;
		}

		private static String stripComments(String line) {
		int index = line.indexOf('#');
		// 'N:' lines (which contain the name of the input device) do not support trailing
		// comments, to support recording device names that contain #s.
		if (index < 0 \|\| line.startsWith("N: ")) {
		return line;
		} else {
		return line.substring(0, index).strip();
		}
		}

		/**
		* Returns the next line of the file that isn't blank when stripped of comments, or
		* {@code null} if the end of the file is reached. However, it does not advance to the
		* next line of the file.
		*/
		public @Nullable String peekLine() {
		return mNextLine;
		}

		/** Moves to the next line of the file. */
		public void advance() throws IOException {
		mNextLine = findNextLine();
		}

		public boolean isAtEndOfFile() {
		return mNextLine == null;
		}
		}

		private final CommentAwareReader mReader;
		/**
		* The timestamp of the last event returned, of the head of {@link #mQueuedEvents} if there is
		* one, or -1 if no events have been returned yet.
		*/
		private long mLastEventTimeMicros = -1;
		private final Queue<Event> mQueuedEvents = new ArrayDeque<>(2);

		public EvemuParser(Reader in) throws IOException {
		mReader = new CommentAwareReader(new BufferedReader(in));
		mQueuedEvents.add(parseRegistrationEvent());

		// The kernel takes a little time to set up an evdev device after the initial
		// registration. Any events that we try to inject during this period would be silently
		// dropped, so we delay for a short period after registration and before injecting any
		// events.
		final Event.Builder delayEb = new Event.Builder();
		delayEb.setId(DEVICE_ID);
		delayEb.setCommand(Event.Command.DELAY);
		delayEb.setDurationMillis(REGISTRATION_DELAY_MILLIS);
		mQueuedEvents.add(delayEb.build());
		}

		/**
		* Returns the next event in the evemu recording.
		*/
		public Event getNextEvent() throws IOException {
		if (!mQueuedEvents.isEmpty()) {
		return mQueuedEvents.remove();
		}

		if (mReader.isAtEndOfFile()) {
		return null;
		}

		final String[] parts = expectLineWithParts("E", 4);
		final String[] timeParts = parts[0].split("\\.");
		if (timeParts.length != 2) {
		throw new RuntimeException("Invalid timestamp (does not contain a '.')");
		}
		// TODO(b/310958309): use timeMicros to set the timestamp on the event being sent.
		final long timeMicros =
		Long.parseLong(timeParts[0]) * 1_000_000 + Integer.parseInt(timeParts[1]);
		final Event.Builder eb = new Event.Builder();
		eb.setId(DEVICE_ID);
		eb.setCommand(Event.Command.INJECT);
		final int eventType = Integer.parseInt(parts[1], 16);
		final int eventCode = Integer.parseInt(parts[2], 16);
		final int value = Integer.parseInt(parts[3]);
		eb.setInjections(new int[] {eventType, eventCode, value});

		if (mLastEventTimeMicros == -1) {
		// This is the first event being injected, so send it straight away.
		mLastEventTimeMicros = timeMicros;
		return eb.build();
		} else {
		final long delayMicros = timeMicros - mLastEventTimeMicros;
		// The shortest delay supported by Handler.sendMessageAtTime (used for timings by the
		// Device class) is 1ms, so ignore time differences smaller than that.
		if (delayMicros < 1000) {
		mLastEventTimeMicros = timeMicros;
		return eb.build();
		} else {
		// Send a delay now, and queue the actual event for the next call.
		mQueuedEvents.add(eb.build());
		mLastEventTimeMicros = timeMicros;
		final Event.Builder delayEb = new Event.Builder();
		delayEb.setId(DEVICE_ID);
		delayEb.setCommand(Event.Command.DELAY);
		delayEb.setDurationMillis((int) (delayMicros / 1000));
		return delayEb.build();
		}
		}
		}

		private Event parseRegistrationEvent() throws IOException {
		// The registration details at the start of a recording are specified by a set of lines
		// that have to be in this order: N, I, P, B, A, L, S. Recordings must have exactly one N
		// (name) and I (IDs) line. The remaining lines are optional, and there may be multiple
		// of those lines.

		final Event.Builder eb = new Event.Builder();
		eb.setId(DEVICE_ID);
		eb.setCommand(Event.Command.REGISTER);
		eb.setName(expectLine("N"));

		final String[] idStrings = expectLineWithParts("I", 4);
		eb.setBusId(Integer.parseInt(idStrings[0], 16));
		eb.setVid(Integer.parseInt(idStrings[1], 16));
		eb.setPid(Integer.parseInt(idStrings[2], 16));
		// TODO(b/302297266): support setting the version ID, and set it to idStrings[3].

		final SparseArray<int[]> config = new SparseArray<>();
		config.append(Event.UinputControlCode.UI_SET_PROPBIT.getValue(), parseProperties());

		parseAxisBitmaps(config);

		eb.setConfiguration(config);
		if (config.contains(Event.UinputControlCode.UI_SET_FFBIT.getValue())) {
		// If the device specifies any force feedback effects, the kernel will require the
		// ff_effects_max value to be set.
		eb.setFfEffectsMax(config.get(Event.UinputControlCode.UI_SET_FFBIT.getValue()).length);
		}

		eb.setAbsInfo(parseAbsInfos());

		// L: and S: lines allow the initial states of the device's LEDs and switches to be
		// recorded. However, the FreeDesktop implementation doesn't support actually setting these
		// states at the start of playback (apparently due to concerns over race conditions), and we
		// have no need for this feature either, so for now just skip over them.
		skipUnsupportedLines("L");
		skipUnsupportedLines("S");

		return eb.build();
		}

		private int[] parseProperties() throws IOException {
		final List<String> propBitmapParts = new ArrayList<>();
		String line = acceptLine("P");
		while (line != null) {
		propBitmapParts.addAll(List.of(line.strip().split(" ")));
		line = acceptLine("P");
		}
		return hexStringBitmapToEventCodes(propBitmapParts);
		}

		private void parseAxisBitmaps(SparseArray<int[]> config) throws IOException {
		final Map<Integer, List<String>> axisBitmapParts = new HashMap<>();
		String line = acceptLine("B");
		while (line != null) {
		final String[] parts = line.strip().split(" ");
		if (parts.length < 2) {
		throw new RuntimeException(
		"Expected event type and at least one bitmap byte on 'B:' line; only found "
		+ parts.length + " elements");
		}
		final int eventType = Integer.parseInt(parts[0], 16);
		// EV_SYN cannot be configured through uinput, so skip it.
		if (eventType != Event.EV_SYN) {
		if (!axisBitmapParts.containsKey(eventType)) {
		axisBitmapParts.put(eventType, new ArrayList<>());
		}
		for (int i = 1; i < parts.length; i++) {
		axisBitmapParts.get(eventType).add(parts[i]);
		}
		}
		line = acceptLine("B");
		}
		final List<Integer> eventTypesToSet = new ArrayList<>();
		for (var entry : axisBitmapParts.entrySet()) {
		if (entry.getValue().size() == 0) {
		continue;
		}
		final Event.UinputControlCode controlCode =
		Event.UinputControlCode.forEventType(entry.getKey());
		final int[] eventCodes = hexStringBitmapToEventCodes(entry.getValue());
		if (controlCode != null && eventCodes.length > 0) {
		config.append(controlCode.getValue(), eventCodes);
		eventTypesToSet.add(entry.getKey());
		}
		}
		config.append(
		Event.UinputControlCode.UI_SET_EVBIT.getValue(), unboxIntList(eventTypesToSet));
		}

		private SparseArray<InputAbsInfo> parseAbsInfos() throws IOException {
		final SparseArray<InputAbsInfo> absInfos = new SparseArray<>();
		String line = acceptLine("A");
		while (line != null) {
		final String[] parts = line.strip().split(" ");
		if (parts.length < 5 \|\| parts.length > 6) {
		throw new RuntimeException(
		"'A:' lines should have the format 'A: <index (hex)> <min> <max> <fuzz> "
		+ "<flat> [<resolution>]'; expected 5 or 6 numbers but found "
		+ parts.length);
		}
		final int axisCode = Integer.parseInt(parts[0], 16);
		final InputAbsInfo info = new InputAbsInfo();
		info.minimum = Integer.parseInt(parts[1]);
		info.maximum = Integer.parseInt(parts[2]);
		info.fuzz = Integer.parseInt(parts[3]);
		info.flat = Integer.parseInt(parts[4]);
		info.resolution = parts.length > 5 ? Integer.parseInt(parts[5]) : 0;
		absInfos.append(axisCode, info);
		line = acceptLine("A");
		}
		return absInfos;
		}

		private void skipUnsupportedLines(String type) throws IOException {
		if (acceptLine(type) != null) {
		while (acceptLine(type) != null) {
		// Skip the line.
		}
		}
		}

		/**
		* Returns the contents of the next line in the file if it has the given type, or raises an
		* error if it does not.
		*
		* @param type the type of the line to expect, represented by the letter before the ':'.
		* @return the part of the line after the ": ".
		*/
		private String expectLine(String type) throws IOException {
		final String line = acceptLine(type);
		if (line == null) {
		throw new RuntimeException("Expected line of type '" + type + "'");
		} else {
		return line;
		}
		}

		/**
		* Peeks at the next line in the file to see if it has the given type, and if so, returns its
		* contents and advances the reader.
		*
		* @param type the type of the line to accept, represented by the letter before the ':'.
		* @return the part of the line after the ": ", if the type matches; otherwise {@code null}.
		*/
		private @Nullable String acceptLine(String type) throws IOException {
		final String line = mReader.peekLine();
		if (line == null) {
		return null;
		}
		final String[] lineParts = line.split(": ", 2);
		if (lineParts.length < 2) {
		// TODO(b/302297266): make a proper exception class for syntax errors, including line
		// numbers, etc.. (We can use LineNumberReader to track them.)
		throw new RuntimeException("Line without ': '");
		}
		if (lineParts[0].equals(type)) {
		mReader.advance();
		return lineParts[1];
		} else {
		return null;
		}
		}

		/**
		* Like {@link #expectLine(String)}, but also checks that the contents of the line is formed of
		* {@code numParts} space-separated parts.
		*
		* @param type the type of the line to expect, represented by the letter before the ':'.
		* @param numParts the number of parts to expect.
		* @return the part of the line after the ": ", split into {@code numParts} sections.
		*/
		private String[] expectLineWithParts(String type, int numParts) throws IOException {
		final String[] parts = expectLine(type).strip().split(" ");
		if (parts.length != numParts) {
		throw new RuntimeException("Expected a '" + type + "' line with " + numParts
		+ " parts, found one with " + parts.length);
		}
		return parts;
		}

		private static int[] hexStringBitmapToEventCodes(List<String> strs) {
		final List<Integer> codes = new ArrayList<>();
		for (int iByte = 0; iByte < strs.size(); iByte++) {
		int b = Integer.parseInt(strs.get(iByte), 16);
		if (b < 0x0 \|\| b > 0xff) {
		throw new RuntimeException("Bitmap part '" + strs.get(iByte)
		+ "' invalid; parts must be between 00 and ff.");
		}
		for (int iBit = 0; iBit < 8; iBit++) {
		if ((b & 1) != 0) {
		codes.add(iByte * 8 + iBit);
		}
		b >>= 1;
		}
		}
		return unboxIntList(codes);
		}

		private static int[] unboxIntList(List<Integer> list) {
		final int[] array = new int[list.size()];
		Arrays.setAll(array, list::get);
		return array;
		}
		}

cmds/uinput/src/com/android/commands/uinput/Event.java

+23 −17

Original line number	Diff line number	Diff line
		@@ -16,6 +16,7 @@

		package com.android.commands.uinput;

		import android.annotation.Nullable;
		import android.util.SparseArray;

		import java.util.Arrays;
		@@ -39,6 +40,7 @@ public class Event {

		// Constants representing evdev event types, from include/uapi/linux/input-event-codes.h in the
		// kernel.
		public static final int EV_SYN = 0x00;
		public static final int EV_KEY = 0x01;
		public static final int EV_REL = 0x02;
		public static final int EV_ABS = 0x03;
		@@ -69,19 +71,23 @@ public class Event {
		public int getValue() {
		return mValue;
		}
		}

		// These constants come from "include/uapi/linux/input.h" in the kernel
		enum Bus {
		USB(0x03), BLUETOOTH(0x05);
		private final int mValue;

		Bus(int value) {
		mValue = value;
		}

		int getValue() {
		return mValue;
		/**
		* Returns the control code for the given evdev event type, or {@code null} if there is no
		* control code for that type.
		*/
		public static @Nullable UinputControlCode forEventType(int eventType) {
		return switch (eventType) {
		case EV_KEY -> UI_SET_KEYBIT;
		case EV_REL -> UI_SET_RELBIT;
		case EV_ABS -> UI_SET_ABSBIT;
		case EV_MSC -> UI_SET_MSCBIT;
		case EV_SW -> UI_SET_SWBIT;
		case EV_LED -> UI_SET_LEDBIT;
		case EV_SND -> UI_SET_SNDBIT;
		case EV_FF -> UI_SET_FFBIT;
		default -> null;
		};
		}
		}

		@@ -90,7 +96,7 @@ public class Event {
		private String mName;
		private int mVid;
		private int mPid;
		private Bus mBus;
		private int mBusId;
		private int[] mInjections;
		private SparseArray<int[]> mConfiguration;
		private int mDurationMillis;
		@@ -120,7 +126,7 @@ public class Event {
		}

		public int getBus() {
		return mBus.getValue();
		return mBusId;
		}

		public int[] getInjections() {
		@@ -168,7 +174,7 @@ public class Event {
		+ ", name=" + mName
		+ ", vid=" + mVid
		+ ", pid=" + mPid
		+ ", bus=" + mBus
		+ ", busId=" + mBusId
		+ ", events=" + Arrays.toString(mInjections)
		+ ", configuration=" + mConfiguration
		+ ", duration=" + mDurationMillis + "ms"
		@@ -218,8 +224,8 @@ public class Event {
		mEvent.mPid = pid;
		}

		public void setBus(Bus bus) {
		mEvent.mBus = bus;
		public void setBusId(int busId) {
		mEvent.mBusId = busId;
		}

		public void setDurationMillis(int durationMillis) {

cmds/uinput/src/com/android/commands/uinput/EventParser.java

0 → 100644

+29 −0

Original line number	Diff line number	Diff line
		/*
		* Copyright 2023 The Android Open Source Project
		*
		* Licensed under the Apache License, Version 2.0 (the "License");
		* you may not use this file except in compliance with the License.
		* You may obtain a copy of the License at
		*
		* http://www.apache.org/licenses/LICENSE-2.0
		*
		* Unless required by applicable law or agreed to in writing, software
		* distributed under the License is distributed on an "AS IS" BASIS,
		* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
		* See the License for the specific language governing permissions and
		* limitations under the License.
		*/

		package com.android.commands.uinput;

		import java.io.IOException;

		/**
		* Interface for a class that reads a stream of {@link Event}s.
		*/
		public interface EventParser {
		/**
		* Returns the next event in the file that the parser is reading from.
		*/
		Event getNextEvent() throws IOException;
		}

cmds/uinput/src/com/android/commands/uinput/JsonStyleParser.java

+32 −6

Original line number	Diff line number	Diff line
		@@ -22,7 +22,7 @@ import android.util.Log;
		import android.util.SparseArray;

		import java.io.IOException;
		import java.io.InputStreamReader;
		import java.io.Reader;
		import java.util.ArrayList;
		import java.util.List;
		import java.util.Objects;
		@@ -34,12 +34,12 @@ import src.com.android.commands.uinput.InputAbsInfo;
		/**
		* A class that parses the JSON-like event format described in the README to build {@link Event}s.
		*/
		public class JsonStyleParser {
		public class JsonStyleParser implements EventParser {
		private static final String TAG = "UinputJsonStyleParser";

		private JsonReader mReader;

		public JsonStyleParser(InputStreamReader in) {
		public JsonStyleParser(Reader in) {
		mReader = new JsonReader(in);
		mReader.setLenient(true);
		}
		@@ -62,7 +62,7 @@ public class JsonStyleParser {
		case "name" -> eb.setName(mReader.nextString());
		case "vid" -> eb.setVid(readInt());
		case "pid" -> eb.setPid(readInt());
		case "bus" -> eb.setBus(readBus());
		case "bus" -> eb.setBusId(readBus());
		case "events" -> {
		int[] injections = readInjectedEvents().stream()
		.mapToInt(Integer::intValue).toArray();
		@@ -139,9 +139,35 @@ public class JsonStyleParser {
		});
		}

		private Event.Bus readBus() throws IOException {
		private int readBus() throws IOException {
		String val = mReader.nextString();
		return Event.Bus.valueOf(val.toUpperCase());
		// See include/uapi/linux/input.h in the kernel for the source of these constants.
		return switch (val.toUpperCase()) {
		case "PCI" -> 0x01;
		case "ISAPNP" -> 0x02;
		case "USB" -> 0x03;
		case "HIL" -> 0x04;
		case "BLUETOOTH" -> 0x05;
		case "VIRTUAL" -> 0x06;
		case "ISA" -> 0x10;
		case "I8042" -> 0x11;
		case "XTKBD" -> 0x12;
		case "RS232" -> 0x13;
		case "GAMEPORT" -> 0x14;
		case "PARPORT" -> 0x15;
		case "AMIGA" -> 0x16;
		case "ADB" -> 0x17;
		case "I2C" -> 0x18;
		case "HOST" -> 0x19;
		case "GSC" -> 0x1A;
		case "ATARI" -> 0x1B;
		case "SPI" -> 0x1C;
		case "RMI" -> 0x1D;
		case "CEC" -> 0x1E;
		case "INTEL_ISHTP" -> 0x1F;
		case "AMD_SFH" -> 0x20;
		default -> throw new IllegalArgumentException("Invalid bus ID " + val);
		};
		}

		private SparseArray<int[]> readConfiguration()

cmds/uinput/src/com/android/commands/uinput/Uinput.java

+24 −4

Original line number	Diff line number	Diff line
		@@ -19,12 +19,12 @@ package com.android.commands.uinput;
		import android.util.Log;
		import android.util.SparseArray;

		import java.io.BufferedReader;
		import java.io.File;
		import java.io.FileInputStream;
		import java.io.IOException;
		import java.io.InputStream;
		import java.io.InputStreamReader;
		import java.io.UnsupportedEncodingException;
		import java.util.Objects;

		/**
		@@ -35,7 +35,7 @@ import java.util.Objects;
		public class Uinput {
		private static final String TAG = "UINPUT";

		private final JsonStyleParser mParser;
		private final EventParser mParser;
		private final SparseArray<Device> mDevices;

		private static void usage() {
		@@ -74,12 +74,32 @@ public class Uinput {
		private Uinput(InputStream in) {
		mDevices = new SparseArray<Device>();
		try {
		mParser = new JsonStyleParser(new InputStreamReader(in, "UTF-8"));
		} catch (UnsupportedEncodingException e) {
		BufferedReader reader = new BufferedReader(new InputStreamReader(in, "UTF-8"));
		mParser = isEvemuFile(reader) ? new EvemuParser(reader) : new JsonStyleParser(reader);
		} catch (IOException e) {
		throw new RuntimeException(e);
		}
		}

		private boolean isEvemuFile(BufferedReader in) throws IOException {
		// After zero or more empty lines (not even containing horizontal whitespace), evemu
		// recordings must either start with '#' (indicating the EVEMU version header or a comment)
		// or 'N' (for the name line). If we encounter anything else, assume it's a JSON-style input
		// file.

		String lineSep = System.lineSeparator();
		char[] buf = new char[1];

		in.mark(1 /* readAheadLimit */);
		int charsRead = in.read(buf);
		while (charsRead > 0 && lineSep.contains(String.valueOf(buf[0]))) {
		in.mark(1 /* readAheadLimit */);
		charsRead = in.read(buf);
		}
		in.reset();
		return buf[0] == '#' \|\| buf[0] == 'N';
		}

		private void run() {
		try {
		Event e = null;