//
// Copyright 2010 The Android Open Source Project
//
// Provides a shared memory transport for input events.
//
#define LOG_TAG "InputTransport"
//#define LOG_NDEBUG 0
// Log debug messages about channel messages (send message, receive message)
#define DEBUG_CHANNEL_MESSAGES 0
// Log debug messages whenever InputChannel objects are created/destroyed
#define DEBUG_CHANNEL_LIFECYCLE 0
// Log debug messages about transport actions
#define DEBUG_TRANSPORT_ACTIONS 0
// Log debug messages about touch event resampling
#define DEBUG_RESAMPLING 0
#include <errno.h>
#include <fcntl.h>
#include <inttypes.h>
#include <math.h>
#include <sys/socket.h>
#include <sys/types.h>
#include <unistd.h>
#include <android-base/stringprintf.h>
#include <binder/Parcel.h>
#include <cutils/properties.h>
#include <log/log.h>
#include <utils/Trace.h>
#include <input/InputTransport.h>
using android::base::StringPrintf;
namespace android {
// Socket buffer size. The default is typically about 128KB, which is much larger than
// we really need. So we make it smaller. It just needs to be big enough to hold
// a few dozen large multi-finger motion events in the case where an application gets
// behind processing touches.
static const size_t SOCKET_BUFFER_SIZE = 32 * 1024;
// Nanoseconds per milliseconds.
static const nsecs_t NANOS_PER_MS = 1000000;
// Latency added during resampling. A few milliseconds doesn't hurt much but
// reduces the impact of mispredicted touch positions.
static const nsecs_t RESAMPLE_LATENCY = 5 * NANOS_PER_MS;
// Minimum time difference between consecutive samples before attempting to resample.
static const nsecs_t RESAMPLE_MIN_DELTA = 2 * NANOS_PER_MS;
// Maximum time difference between consecutive samples before attempting to resample
// by extrapolation.
static const nsecs_t RESAMPLE_MAX_DELTA = 20 * NANOS_PER_MS;
// Maximum time to predict forward from the last known state, to avoid predicting too
// far into the future. This time is further bounded by 50% of the last time delta.
static const nsecs_t RESAMPLE_MAX_PREDICTION = 8 * NANOS_PER_MS;
/**
* System property for enabling / disabling touch resampling.
* Resampling extrapolates / interpolates the reported touch event coordinates to better
* align them to the VSYNC signal, thus resulting in smoother scrolling performance.
* Resampling is not needed (and should be disabled) on hardware that already
* has touch events triggered by VSYNC.
* Set to "1" to enable resampling (default).
* Set to "0" to disable resampling.
* Resampling is enabled by default.
*/
static const char* PROPERTY_RESAMPLING_ENABLED = "ro.input.resampling";
template<typename T>
inline static T min(const T& a, const T& b) {
return a < b ? a : b;
}
inline static float lerp(float a, float b, float alpha) {
return a + alpha * (b - a);
}
inline static bool isPointerEvent(int32_t source) {
return (source & AINPUT_SOURCE_CLASS_POINTER) == AINPUT_SOURCE_CLASS_POINTER;
}
// --- InputMessage ---
bool InputMessage::isValid(size_t actualSize) const {
if (size() == actualSize) {
switch (header.type) {
case TYPE_KEY:
return true;
case TYPE_MOTION:
return body.motion.pointerCount > 0
&& body.motion.pointerCount <= MAX_POINTERS;
case TYPE_FINISHED:
return true;
}
}
return false;
}
size_t InputMessage::size() const {
switch (header.type) {
case TYPE_KEY:
return sizeof(Header) + body.key.size();
case TYPE_MOTION:
return sizeof(Header) + body.motion.size();
case TYPE_FINISHED:
return sizeof(Header) + body.finished.size();
}
return sizeof(Header);
}
/**
* There could be non-zero bytes in-between InputMessage fields. Force-initialize the entire
* memory to zero, then only copy the valid bytes on a per-field basis.
*/
void InputMessage::getSanitizedCopy(InputMessage* msg) const {
memset(msg, 0, sizeof(*msg));
// Write the header
msg->header.type = header.type;
// Write the body
switch(header.type) {
case InputMessage::TYPE_KEY: {
// uint32_t seq
msg->body.key.seq = body.key.seq;
// nsecs_t eventTime
msg->body.key.eventTime = body.key.eventTime;
// int32_t deviceId
msg->body.key.deviceId = body.key.deviceId;
// int32_t source
msg->body.key.source = body.key.source;
// int32_t displayId
msg->body.key.displayId = body.key.displayId;
// int32_t action
msg->body.key.action = body.key.action;
// int32_t flags
msg->body.key.flags = body.key.flags;
// int32_t keyCode
msg->body.key.keyCode = body.key.keyCode;
// int32_t scanCode
msg->body.key.scanCode = body.key.scanCode;
// int32_t metaState
msg->body.key.metaState = body.key.metaState;
// int32_t repeatCount
msg->body.key.repeatCount = body.key.repeatCount;
// nsecs_t downTime
msg->body.key.downTime = body.key.downTime;
break;
}
case InputMessage::TYPE_MOTION: {
// uint32_t seq
msg->body.motion.seq = body.motion.seq;
// nsecs_t eventTime
msg->body.motion.eventTime = body.motion.eventTime;
// int32_t deviceId
msg->body.motion.deviceId = body.motion.deviceId;
// int32_t source
msg->body.motion.source = body.motion.source;
// int32_t displayId
msg->body.motion.displayId = body.motion.displayId;
// int32_t action
msg->body.motion.action = body.motion.action;
// int32_t actionButton
msg->body.motion.actionButton = body.motion.actionButton;
// int32_t flags
msg->body.motion.flags = body.motion.flags;
// int32_t metaState
msg->body.motion.metaState = body.motion.metaState;
// int32_t buttonState
msg->body.motion.buttonState = body.motion.buttonState;
// MotionClassification classification
msg->body.motion.classification = body.motion.classification;
// int32_t edgeFlags
msg->body.motion.edgeFlags = body.motion.edgeFlags;
// nsecs_t downTime
msg->body.motion.downTime = body.motion.downTime;
// float xOffset
msg->body.motion.xOffset = body.motion.xOffset;
// float yOffset
msg->body.motion.yOffset = body.motion.yOffset;
// float xPrecision
msg->body.motion.xPrecision = body.motion.xPrecision;
// float yPrecision
msg->body.motion.yPrecision = body.motion.yPrecision;
// uint32_t pointerCount
msg->body.motion.pointerCount = body.motion.pointerCount;
//struct Pointer pointers[MAX_POINTERS]
for (size_t i = 0; i < body.motion.pointerCount; i++) {
// PointerProperties properties
msg->body.motion.pointers[i].properties.id = body.motion.pointers[i].properties.id;
msg->body.motion.pointers[i].properties.toolType =
body.motion.pointers[i].properties.toolType,
// PointerCoords coords
msg->body.motion.pointers[i].coords.bits = body.motion.pointers[i].coords.bits;
const uint32_t count = BitSet64::count(body.motion.pointers[i].coords.bits);
memcpy(&msg->body.motion.pointers[i].coords.values[0],
&body.motion.pointers[i].coords.values[0],
count * (sizeof(body.motion.pointers[i].coords.values[0])));
}
break;
}
case InputMessage::TYPE_FINISHED: {
msg->body.finished.seq = body.finished.seq;
msg->body.finished.handled = body.finished.handled;
break;
}
default: {
LOG_FATAL("Unexpected message type %i", header.type);
break;
}
}
}
// --- InputChannel ---
InputChannel::InputChannel(const std::string& name, int fd) :
mName(name) {
#if DEBUG_CHANNEL_LIFECYCLE
ALOGD("Input channel constructed: name='%s', fd=%d",
mName.c_str(), fd);
#endif
setFd(fd);
}
InputChannel::~InputChannel() {
#if DEBUG_CHANNEL_LIFECYCLE
ALOGD("Input channel destroyed: name='%s', fd=%d",
mName.c_str(), mFd);
#endif
::close(mFd);
}
void InputChannel::setFd(int fd) {
if (mFd > 0) {
::close(mFd);
}
mFd = fd;
if (mFd > 0) {
int result = fcntl(mFd, F_SETFL, O_NONBLOCK);
LOG_ALWAYS_FATAL_IF(result != 0, "channel '%s' ~ Could not make socket "
"non-blocking. errno=%d", mName.c_str(), errno);
}
}
status_t InputChannel::openInputChannelPair(const std::string& name,
sp<InputChannel>& outServerChannel, sp<InputChannel>& outClientChannel) {
int sockets[2];
if (socketpair(AF_UNIX, SOCK_SEQPACKET, 0, sockets)) {
status_t result = -errno;
ALOGE("channel '%s' ~ Could not create socket pair. errno=%d",
name.c_str(), errno);
outServerChannel.clear();
outClientChannel.clear();
return result;
}
int bufferSize = SOCKET_BUFFER_SIZE;
setsockopt(sockets[0], SOL_SOCKET, SO_SNDBUF, &bufferSize, sizeof(bufferSize));
setsockopt(sockets[0], SOL_SOCKET, SO_RCVBUF, &bufferSize, sizeof(bufferSize));
setsockopt(sockets[1], SOL_SOCKET, SO_SNDBUF, &bufferSize, sizeof(bufferSize));
setsockopt(sockets[1], SOL_SOCKET, SO_RCVBUF, &bufferSize, sizeof(bufferSize));
std::string serverChannelName = name;
serverChannelName += " (server)";
outServerChannel = new InputChannel(serverChannelName, sockets[0]);
std::string clientChannelName = name;
clientChannelName += " (client)";
outClientChannel = new InputChannel(clientChannelName, sockets[1]);
return OK;
}
status_t InputChannel::sendMessage(const InputMessage* msg) {
const size_t msgLength = msg->size();
InputMessage cleanMsg;
msg->getSanitizedCopy(&cleanMsg);
ssize_t nWrite;
do {
nWrite = ::send(mFd, &cleanMsg, msgLength, MSG_DONTWAIT | MSG_NOSIGNAL);
} while (nWrite == -1 && errno == EINTR);
if (nWrite < 0) {
int error = errno;
#if DEBUG_CHANNEL_MESSAGES
ALOGD("channel '%s' ~ error sending message of type %d, errno=%d", mName.c_str(),
msg->header.type, error);
#endif
if (error == EAGAIN || error == EWOULDBLOCK) {
return WOULD_BLOCK;
}
if (error == EPIPE || error == ENOTCONN || error == ECONNREFUSED || error == ECONNRESET) {
return DEAD_OBJECT;
}
return -error;
}
if (size_t(nWrite) != msgLength) {
#if DEBUG_CHANNEL_MESSAGES
ALOGD("channel '%s' ~ error sending message type %d, send was incomplete",
mName.c_str(), msg->header.type);
#endif
return DEAD_OBJECT;
}
#if DEBUG_CHANNEL_MESSAGES
ALOGD("channel '%s' ~ sent message of type %d", mName.c_str(), msg->header.type);
#endif
return OK;
}
status_t InputChannel::receiveMessage(InputMessage* msg) {
ssize_t nRead;
do {
nRead = ::recv(mFd, msg, sizeof(InputMessage), MSG_DONTWAIT);
} while (nRead == -1 && errno == EINTR);
if (nRead < 0) {
int error = errno;
#if DEBUG_CHANNEL_MESSAGES
ALOGD("channel '%s' ~ receive message failed, errno=%d", mName.c_str(), errno);
#endif
if (error == EAGAIN || error == EWOULDBLOCK) {
return WOULD_BLOCK;
}
if (error == EPIPE || error == ENOTCONN || error == ECONNREFUSED) {
return DEAD_OBJECT;
}
return -error;
}
if (nRead == 0) { // check for EOF
#if DEBUG_CHANNEL_MESSAGES
ALOGD("channel '%s' ~ receive message failed because peer was closed", mName.c_str());
#endif
return DEAD_OBJECT;
}
if (!msg->isValid(nRead)) {
#if DEBUG_CHANNEL_MESSAGES
ALOGD("channel '%s' ~ received invalid message", mName.c_str());
#endif
return BAD_VALUE;
}
#if DEBUG_CHANNEL_MESSAGES
ALOGD("channel '%s' ~ received message of type %d", mName.c_str(), msg->header.type);
#endif
return OK;
}
sp<InputChannel> InputChannel::dup() const {
int fd = ::dup(getFd());
return fd >= 0 ? new InputChannel(getName(), fd) : nullptr;
}
status_t InputChannel::write(Parcel& out) const {
status_t s = out.writeString8(String8(getName().c_str()));
if (s != OK) {
return s;
}
s = out.writeStrongBinder(mToken);
if (s != OK) {
return s;
}
s = out.writeDupFileDescriptor(getFd());
return s;
}
status_t InputChannel::read(const Parcel& from) {
mName = from.readString8();
mToken = from.readStrongBinder();
int rawFd = from.readFileDescriptor();
setFd(::dup(rawFd));
if (mFd < 0) {
return BAD_VALUE;
}
return OK;
}
sp<IBinder> InputChannel::getToken() const {
return mToken;
}
void InputChannel::setToken(const sp<IBinder>& token) {
if (mToken != nullptr) {
ALOGE("Assigning InputChannel (%s) a second handle?", mName.c_str());
}
mToken = token;
}
// --- InputPublisher ---
InputPublisher::InputPublisher(const sp<InputChannel>& channel) :
mChannel(channel) {
}
InputPublisher::~InputPublisher() {
}
status_t InputPublisher::publishKeyEvent(
uint32_t seq,
int32_t deviceId,
int32_t source,
int32_t displayId,
int32_t action,
int32_t flags,
int32_t keyCode,
int32_t scanCode,
int32_t metaState,
int32_t repeatCount,
nsecs_t downTime,
nsecs_t eventTime) {
if (ATRACE_ENABLED()) {
std::string message = StringPrintf("publishKeyEvent(inputChannel=%s, keyCode=%" PRId32 ")",
mChannel->getName().c_str(), keyCode);
ATRACE_NAME(message.c_str());
}
#if DEBUG_TRANSPORT_ACTIONS
ALOGD("channel '%s' publisher ~ publishKeyEvent: seq=%u, deviceId=%d, source=0x%x, "
"action=0x%x, flags=0x%x, keyCode=%d, scanCode=%d, metaState=0x%x, repeatCount=%d,"
"downTime=%" PRId64 ", eventTime=%" PRId64,
mChannel->getName().c_str(), seq,
deviceId, source, action, flags, keyCode, scanCode, metaState, repeatCount,
downTime, eventTime);
#endif
if (!seq) {
ALOGE("Attempted to publish a key event with sequence number 0.");
return BAD_VALUE;
}
InputMessage msg;
msg.header.type = InputMessage::TYPE_KEY;
msg.body.key.seq = seq;
msg.body.key.deviceId = deviceId;
msg.body.key.source = source;
msg.body.key.displayId = displayId;
msg.body.key.action = action;
msg.body.key.flags = flags;
msg.body.key.keyCode = keyCode;
msg.body.key.scanCode = scanCode;
msg.body.key.metaState = metaState;
msg.body.key.repeatCount = repeatCount;
msg.body.key.downTime = downTime;
msg.body.key.eventTime = eventTime;
return mChannel->sendMessage(&msg);
}
status_t InputPublisher::publishMotionEvent(
uint32_t seq,
int32_t deviceId,
int32_t source,
int32_t displayId,
int32_t action,
int32_t actionButton,
int32_t flags,
int32_t edgeFlags,
int32_t metaState,
int32_t buttonState,
MotionClassification classification,
float xOffset,
float yOffset,
float xPrecision,
float yPrecision,
nsecs_t downTime,
nsecs_t eventTime,
uint32_t pointerCount,
const PointerProperties* pointerProperties,
const PointerCoords* pointerCoords) {
if (ATRACE_ENABLED()) {
std::string message = StringPrintf(
"publishMotionEvent(inputChannel=%s, action=%" PRId32 ")",
mChannel->getName().c_str(), action);
ATRACE_NAME(message.c_str());
}
#if DEBUG_TRANSPORT_ACTIONS
ALOGD("channel '%s' publisher ~ publishMotionEvent: seq=%u, deviceId=%d, source=0x%x, "
"displayId=%" PRId32 ", "
"action=0x%x, actionButton=0x%08x, flags=0x%x, edgeFlags=0x%x, "
"metaState=0x%x, buttonState=0x%x, classification=%s, xOffset=%f, yOffset=%f, "
"xPrecision=%f, yPrecision=%f, downTime=%" PRId64 ", eventTime=%" PRId64 ", "
"pointerCount=%" PRIu32,
mChannel->getName().c_str(), seq,
deviceId, source, displayId, action, actionButton, flags, edgeFlags, metaState,
buttonState, motionClassificationToString(classification),
xOffset, yOffset, xPrecision, yPrecision, downTime, eventTime, pointerCount);
#endif
if (!seq) {
ALOGE("Attempted to publish a motion event with sequence number 0.");
return BAD_VALUE;
}
if (pointerCount > MAX_POINTERS || pointerCount < 1) {
ALOGE("channel '%s' publisher ~ Invalid number of pointers provided: %" PRIu32 ".",
mChannel->getName().c_str(), pointerCount);
return BAD_VALUE;
}
InputMessage msg;
msg.header.type = InputMessage::TYPE_MOTION;
msg.body.motion.seq = seq;
msg.body.motion.deviceId = deviceId;
msg.body.motion.source = source;
msg.body.motion.displayId = displayId;
msg.body.motion.action = action;
msg.body.motion.actionButton = actionButton;
msg.body.motion.flags = flags;
msg.body.motion.edgeFlags = edgeFlags;
msg.body.motion.metaState = metaState;
msg.body.motion.buttonState = buttonState;
msg.body.motion.classification = classification;
msg.body.motion.xOffset = xOffset;
msg.body.motion.yOffset = yOffset;
msg.body.motion.xPrecision = xPrecision;
msg.body.motion.yPrecision = yPrecision;
msg.body.motion.downTime = downTime;
msg.body.motion.eventTime = eventTime;
msg.body.motion.pointerCount = pointerCount;
for (uint32_t i = 0; i < pointerCount; i++) {
msg.body.motion.pointers[i].properties.copyFrom(pointerProperties[i]);
msg.body.motion.pointers[i].coords.copyFrom(pointerCoords[i]);
}
return mChannel->sendMessage(&msg);
}
status_t InputPublisher::receiveFinishedSignal(uint32_t* outSeq, bool* outHandled) {
#if DEBUG_TRANSPORT_ACTIONS
ALOGD("channel '%s' publisher ~ receiveFinishedSignal",
mChannel->getName().c_str());
#endif
InputMessage msg;
status_t result = mChannel->receiveMessage(&msg);
if (result) {
*outSeq = 0;
*outHandled = false;
return result;
}
if (msg.header.type != InputMessage::TYPE_FINISHED) {
ALOGE("channel '%s' publisher ~ Received unexpected message of type %d from consumer",
mChannel->getName().c_str(), msg.header.type);
return UNKNOWN_ERROR;
}
*outSeq = msg.body.finished.seq;
*outHandled = msg.body.finished.handled;
return OK;
}
// --- InputConsumer ---
InputConsumer::InputConsumer(const sp<InputChannel>& channel) :
mResampleTouch(isTouchResamplingEnabled()),
mChannel(channel), mMsgDeferred(false) {
}
InputConsumer::~InputConsumer() {
}
bool InputConsumer::isTouchResamplingEnabled() {
return property_get_bool(PROPERTY_RESAMPLING_ENABLED, true);
}
status_t InputConsumer::consume(InputEventFactoryInterface* factory,
bool consumeBatches, nsecs_t frameTime, uint32_t* outSeq, InputEvent** outEvent) {
#if DEBUG_TRANSPORT_ACTIONS
ALOGD("channel '%s' consumer ~ consume: consumeBatches=%s, frameTime=%" PRId64,
mChannel->getName().c_str(), consumeBatches ? "true" : "false", frameTime);
#endif
*outSeq = 0;
*outEvent = nullptr;
// Fetch the next input message.
// Loop until an event can be returned or no additional events are received.
while (!*outEvent) {
if (mMsgDeferred) {
// mMsg contains a valid input message from the previous call to consume
// that has not yet been processed.
mMsgDeferred = false;
} else {
// Receive a fresh message.
status_t result = mChannel->receiveMessage(&mMsg);
if (result) {
// Consume the next batched event unless batches are being held for later.
if (consumeBatches || result != WOULD_BLOCK) {
result = consumeBatch(factory, frameTime, outSeq, outEvent);
if (*outEvent) {
#if DEBUG_TRANSPORT_ACTIONS
ALOGD("channel '%s' consumer ~ consumed batch event, seq=%u",
mChannel->getName().c_str(), *outSeq);
#endif
break;
}
}
return result;
}
}
switch (mMsg.header.type) {
case InputMessage::TYPE_KEY: {
KeyEvent* keyEvent = factory->createKeyEvent();
if (!keyEvent) return NO_MEMORY;
initializeKeyEvent(keyEvent, &mMsg);
*outSeq = mMsg.body.key.seq;
*outEvent = keyEvent;
#if DEBUG_TRANSPORT_ACTIONS
ALOGD("channel '%s' consumer ~ consumed key event, seq=%u",
mChannel->getName().c_str(), *outSeq);
#endif
break;
}
case InputMessage::TYPE_MOTION: {
ssize_t batchIndex = findBatch(mMsg.body.motion.deviceId, mMsg.body.motion.source);
if (batchIndex >= 0) {
Batch& batch = mBatches.editItemAt(batchIndex);
if (canAddSample(batch, &mMsg)) {
batch.samples.push(mMsg);
#if DEBUG_TRANSPORT_ACTIONS
ALOGD("channel '%s' consumer ~ appended to batch event",
mChannel->getName().c_str());
#endif
break;
} else if (isPointerEvent(mMsg.body.motion.source) &&
mMsg.body.motion.action == AMOTION_EVENT_ACTION_CANCEL) {
// No need to process events that we are going to cancel anyways
const size_t count = batch.samples.size();
for (size_t i = 0; i < count; i++) {
const InputMessage& msg = batch.samples.itemAt(i);
sendFinishedSignal(msg.body.motion.seq, false);
}
batch.samples.removeItemsAt(0, count);
mBatches.removeAt(batchIndex);
} else {
// We cannot append to the batch in progress, so we need to consume
// the previous batch right now and defer the new message until later.
mMsgDeferred = true;
status_t result = consumeSamples(factory,
batch, batch.samples.size(), outSeq, outEvent);
mBatches.removeAt(batchIndex);
if (result) {
return result;
}
#if DEBUG_TRANSPORT_ACTIONS
ALOGD("channel '%s' consumer ~ consumed batch event and "
"deferred current event, seq=%u",
mChannel->getName().c_str(), *outSeq);
#endif
break;
}
}
// Start a new batch if needed.
if (mMsg.body.motion.action == AMOTION_EVENT_ACTION_MOVE
|| mMsg.body.motion.action == AMOTION_EVENT_ACTION_HOVER_MOVE) {
mBatches.push();
Batch& batch = mBatches.editTop();
batch.samples.push(mMsg);
#if DEBUG_TRANSPORT_ACTIONS
ALOGD("channel '%s' consumer ~ started batch event",
mChannel->getName().c_str());
#endif
break;
}
MotionEvent* motionEvent = factory->createMotionEvent();
if (! motionEvent) return NO_MEMORY;
updateTouchState(mMsg);
initializeMotionEvent(motionEvent, &mMsg);
*outSeq = mMsg.body.motion.seq;
*outEvent = motionEvent;
#if DEBUG_TRANSPORT_ACTIONS
ALOGD("channel '%s' consumer ~ consumed motion event, seq=%u",
mChannel->getName().c_str(), *outSeq);
#endif
break;
}
default:
ALOGE("channel '%s' consumer ~ Received unexpected message of type %d",
mChannel->getName().c_str(), mMsg.header.type);
return UNKNOWN_ERROR;
}
}
return OK;
}
status_t InputConsumer::consumeBatch(InputEventFactoryInterface* factory,
nsecs_t frameTime, uint32_t* outSeq, InputEvent** outEvent) {
status_t result;
for (size_t i = mBatches.size(); i > 0; ) {
i--;
Batch& batch = mBatches.editItemAt(i);
if (frameTime < 0) {
result = consumeSamples(factory, batch, batch.samples.size(), outSeq, outEvent);
mBatches.removeAt(i);
return result;
}
nsecs_t sampleTime = frameTime;
if (mResampleTouch) {
sampleTime -= RESAMPLE_LATENCY;
}
ssize_t split = findSampleNoLaterThan(batch, sampleTime);
if (split < 0) {
continue;
}
result = consumeSamples(factory, batch, split + 1, outSeq, outEvent);
const InputMessage* next;
if (batch.samples.isEmpty()) {
mBatches.removeAt(i);
next = nullptr;
} else {
next = &batch.samples.itemAt(0);
}
if (!result && mResampleTouch) {
resampleTouchState(sampleTime, static_cast<MotionEvent*>(*outEvent), next);
}
return result;
}
return WOULD_BLOCK;
}
status_t InputConsumer::consumeSamples(InputEventFactoryInterface* factory,
Batch& batch, size_t count, uint32_t* outSeq, InputEvent** outEvent) {
MotionEvent* motionEvent = factory->createMotionEvent();
if (! motionEvent) return NO_MEMORY;
uint32_t chain = 0;
for (size_t i = 0; i < count; i++) {
InputMessage& msg = batch.samples.editItemAt(i);
updateTouchState(msg);
if (i) {
SeqChain seqChain;
seqChain.seq = msg.body.motion.seq;
seqChain.chain = chain;
mSeqChains.push(seqChain);
addSample(motionEvent, &msg);
} else {
initializeMotionEvent(motionEvent, &msg);
}
chain = msg.body.motion.seq;
}
batch.samples.removeItemsAt(0, count);
*outSeq = chain;
*outEvent = motionEvent;
return OK;
}
void InputConsumer::updateTouchState(InputMessage& msg) {
if (!mResampleTouch || !isPointerEvent(msg.body.motion.source)) {
return;
}
int32_t deviceId = msg.body.motion.deviceId;
int32_t source = msg.body.motion.source;
// Update the touch state history to incorporate the new input message.
// If the message is in the past relative to the most recently produced resampled
// touch, then use the resampled time and coordinates instead.
switch (msg.body.motion.action & AMOTION_EVENT_ACTION_MASK) {
case AMOTION_EVENT_ACTION_DOWN: {
ssize_t index = findTouchState(deviceId, source);
if (index < 0) {
mTouchStates.push();
index = mTouchStates.size() - 1;
}
TouchState& touchState = mTouchStates.editItemAt(index);
touchState.initialize(deviceId, source);
touchState.addHistory(msg);
break;
}
case AMOTION_EVENT_ACTION_MOVE: {
ssize_t index = findTouchState(deviceId, source);
if (index >= 0) {
TouchState& touchState = mTouchStates.editItemAt(index);
touchState.addHistory(msg);
rewriteMessage(touchState, msg);
}
break;
}
case AMOTION_EVENT_ACTION_POINTER_DOWN: {
ssize_t index = findTouchState(deviceId, source);
if (index >= 0) {
TouchState& touchState = mTouchStates.editItemAt(index);
touchState.lastResample.idBits.clearBit(msg.body.motion.getActionId());
rewriteMessage(touchState, msg);
}
break;
}
case AMOTION_EVENT_ACTION_POINTER_UP: {
ssize_t index = findTouchState(deviceId, source);
if (index >= 0) {
TouchState& touchState = mTouchStates.editItemAt(index);
rewriteMessage(touchState, msg);
touchState.lastResample.idBits.clearBit(msg.body.motion.getActionId());
}
break;
}
case AMOTION_EVENT_ACTION_SCROLL: {
ssize_t index = findTouchState(deviceId, source);
if (index >= 0) {
TouchState& touchState = mTouchStates.editItemAt(index);
rewriteMessage(touchState, msg);
}
break;
}
case AMOTION_EVENT_ACTION_UP:
case AMOTION_EVENT_ACTION_CANCEL: {
ssize_t index = findTouchState(deviceId, source);
if (index >= 0) {
TouchState& touchState = mTouchStates.editItemAt(index);
rewriteMessage(touchState, msg);
mTouchStates.removeAt(index);
}
break;
}
}
}
/**
* Replace the coordinates in msg with the coordinates in lastResample, if necessary.
*
* If lastResample is no longer valid for a specific pointer (i.e. the lastResample time
* is in the past relative to msg and the past two events do not contain identical coordinates),
* then invalidate the lastResample data for that pointer.
* If the two past events have identical coordinates, then lastResample data for that pointer will
* remain valid, and will be used to replace these coordinates. Thus, if a certain coordinate x0 is
* resampled to the new value x1, then x1 will always be used to replace x0 until some new value
* not equal to x0 is received.
*/
void InputConsumer::rewriteMessage(TouchState& state, InputMessage& msg) {
nsecs_t eventTime = msg.body.motion.eventTime;
for (uint32_t i = 0; i < msg.body.motion.pointerCount; i++) {
uint32_t id = msg.body.motion.pointers[i].properties.id;
if (state.lastResample.idBits.hasBit(id)) {
if (eventTime < state.lastResample.eventTime ||
state.recentCoordinatesAreIdentical(id)) {
PointerCoords& msgCoords = msg.body.motion.pointers[i].coords;
const PointerCoords& resampleCoords = state.lastResample.getPointerById(id);
#if DEBUG_RESAMPLING
ALOGD("[%d] - rewrite (%0.3f, %0.3f), old (%0.3f, %0.3f)", id,
resampleCoords.getX(), resampleCoords.getY(),
msgCoords.getX(), msgCoords.getY());
#endif
msgCoords.setAxisValue(AMOTION_EVENT_AXIS_X, resampleCoords.getX());
msgCoords.setAxisValue(AMOTION_EVENT_AXIS_Y, resampleCoords.getY());
} else {
state.lastResample.idBits.clearBit(id);
}
}
}
}
void InputConsumer::resampleTouchState(nsecs_t sampleTime, MotionEvent* event,
const InputMessage* next) {
if (!mResampleTouch
|| !(isPointerEvent(event->getSource()))
|| event->getAction() != AMOTION_EVENT_ACTION_MOVE) {
return;
}
ssize_t index = findTouchState(event->getDeviceId(), event->getSource());
if (index < 0) {
#if DEBUG_RESAMPLING
ALOGD("Not resampled, no touch state for device.");
#endif
return;
}
TouchState& touchState = mTouchStates.editItemAt(index);
if (touchState.historySize < 1) {
#if DEBUG_RESAMPLING
ALOGD("Not resampled, no history for device.");
#endif
return;
}
// Ensure that the current sample has all of the pointers that need to be reported.
const History* current = touchState.getHistory(0);
size_t pointerCount = event->getPointerCount();
for (size_t i = 0; i < pointerCount; i++) {
uint32_t id = event->getPointerId(i);
if (!current->idBits.hasBit(id)) {
#if DEBUG_RESAMPLING
ALOGD("Not resampled, missing id %d", id);
#endif
return;
}
}
// Find the data to use for resampling.
const History* other;
History future;
float alpha;
if (next) {
// Interpolate between current sample and future sample.
// So current->eventTime <= sampleTime <= future.eventTime.
future.initializeFrom(*next);
other = &future;
nsecs_t delta = future.eventTime - current->eventTime;
if (delta < RESAMPLE_MIN_DELTA) {
#if DEBUG_RESAMPLING
ALOGD("Not resampled, delta time is too small: %" PRId64 " ns.", delta);
#endif
return;
}
alpha = float(sampleTime - current->eventTime) / delta;
} else if (touchState.historySize >= 2) {
// Extrapolate future sample using current sample and past sample.
// So other->eventTime <= current->eventTime <= sampleTime.
other = touchState.getHistory(1);
nsecs_t delta = current->eventTime - other->eventTime;
if (delta < RESAMPLE_MIN_DELTA) {
#if DEBUG_RESAMPLING
ALOGD("Not resampled, delta time is too small: %" PRId64 " ns.", delta);
#endif
return;
} else if (delta > RESAMPLE_MAX_DELTA) {
#if DEBUG_RESAMPLING
ALOGD("Not resampled, delta time is too large: %" PRId64 " ns.", delta);
#endif
return;
}
nsecs_t maxPredict = current->eventTime + min(delta / 2, RESAMPLE_MAX_PREDICTION);
if (sampleTime > maxPredict) {
#if DEBUG_RESAMPLING
ALOGD("Sample time is too far in the future, adjusting prediction "
"from %" PRId64 " to %" PRId64 " ns.",
sampleTime - current->eventTime, maxPredict - current->eventTime);
#endif
sampleTime = maxPredict;
}
alpha = float(current->eventTime - sampleTime) / delta;
} else {
#if DEBUG_RESAMPLING
ALOGD("Not resampled, insufficient data.");
#endif
return;
}
// Resample touch coordinates.
History oldLastResample;
oldLastResample.initializeFrom(touchState.lastResample);
touchState.lastResample.eventTime = sampleTime;
touchState.lastResample.idBits.clear();
for (size_t i = 0; i < pointerCount; i++) {
uint32_t id = event->getPointerId(i);
touchState.lastResample.idToIndex[id] = i;
touchState.lastResample.idBits.markBit(id);
if (oldLastResample.hasPointerId(id) && touchState.recentCoordinatesAreIdentical(id)) {
// We maintain the previously resampled value for this pointer (stored in
// oldLastResample) when the coordinates for this pointer haven't changed since then.
// This way we don't introduce artificial jitter when pointers haven't actually moved.
// We know here that the coordinates for the pointer haven't changed because we
// would've cleared the resampled bit in rewriteMessage if they had. We can't modify
// lastResample in place becasue the mapping from pointer ID to index may have changed.
touchState.lastResample.pointers[i].copyFrom(oldLastResample.getPointerById(id));
continue;
}
PointerCoords& resampledCoords = touchState.lastResample.pointers[i];
const PointerCoords& currentCoords = current->getPointerById(id);
resampledCoords.copyFrom(currentCoords);
if (other->idBits.hasBit(id)
&& shouldResampleTool(event->getToolType(i))) {
const PointerCoords& otherCoords = other->getPointerById(id);
resampledCoords.setAxisValue(AMOTION_EVENT_AXIS_X,
lerp(currentCoords.getX(), otherCoords.getX(), alpha));
resampledCoords.setAxisValue(AMOTION_EVENT_AXIS_Y,
lerp(currentCoords.getY(), otherCoords.getY(), alpha));
#if DEBUG_RESAMPLING
ALOGD("[%d] - out (%0.3f, %0.3f), cur (%0.3f, %0.3f), "
"other (%0.3f, %0.3f), alpha %0.3f",
id, resampledCoords.getX(), resampledCoords.getY(),
currentCoords.getX(), currentCoords.getY(),
otherCoords.getX(), otherCoords.getY(),
alpha);
#endif
} else {
#if DEBUG_RESAMPLING
ALOGD("[%d] - out (%0.3f, %0.3f), cur (%0.3f, %0.3f)",
id, resampledCoords.getX(), resampledCoords.getY(),
currentCoords.getX(), currentCoords.getY());
#endif
}
}
event->addSample(sampleTime, touchState.lastResample.pointers);
}
bool InputConsumer::shouldResampleTool(int32_t toolType) {
return toolType == AMOTION_EVENT_TOOL_TYPE_FINGER
|| toolType == AMOTION_EVENT_TOOL_TYPE_UNKNOWN;
}
status_t InputConsumer::sendFinishedSignal(uint32_t seq, bool handled) {
#if DEBUG_TRANSPORT_ACTIONS
ALOGD("channel '%s' consumer ~ sendFinishedSignal: seq=%u, handled=%s",
mChannel->getName().c_str(), seq, handled ? "true" : "false");
#endif
if (!seq) {
ALOGE("Attempted to send a finished signal with sequence number 0.");
return BAD_VALUE;
}
// Send finished signals for the batch sequence chain first.
size_t seqChainCount = mSeqChains.size();
if (seqChainCount) {
uint32_t currentSeq = seq;
uint32_t chainSeqs[seqChainCount];
size_t chainIndex = 0;
for (size_t i = seqChainCount; i > 0; ) {
i--;
const SeqChain& seqChain = mSeqChains.itemAt(i);
if (seqChain.seq == currentSeq) {
currentSeq = seqChain.chain;
chainSeqs[chainIndex++] = currentSeq;
mSeqChains.removeAt(i);
}
}
status_t status = OK;
while (!status && chainIndex > 0) {
chainIndex--;
status = sendUnchainedFinishedSignal(chainSeqs[chainIndex], handled);
}
if (status) {
// An error occurred so at least one signal was not sent, reconstruct the chain.
for (;;) {
SeqChain seqChain;
seqChain.seq = chainIndex != 0 ? chainSeqs[chainIndex - 1] : seq;
seqChain.chain = chainSeqs[chainIndex];
mSeqChains.push(seqChain);
if (!chainIndex) break;
chainIndex--;
}
return status;
}
}
// Send finished signal for the last message in the batch.
return sendUnchainedFinishedSignal(seq, handled);
}
status_t InputConsumer::sendUnchainedFinishedSignal(uint32_t seq, bool handled) {
InputMessage msg;
msg.header.type = InputMessage::TYPE_FINISHED;
msg.body.finished.seq = seq;
msg.body.finished.handled = handled;
return mChannel->sendMessage(&msg);
}
bool InputConsumer::hasDeferredEvent() const {
return mMsgDeferred;
}
bool InputConsumer::hasPendingBatch() const {
return !mBatches.isEmpty();
}
ssize_t InputConsumer::findBatch(int32_t deviceId, int32_t source) const {
for (size_t i = 0; i < mBatches.size(); i++) {
const Batch& batch = mBatches.itemAt(i);
const InputMessage& head = batch.samples.itemAt(0);
if (head.body.motion.deviceId == deviceId && head.body.motion.source == source) {
return i;
}
}
return -1;
}
ssize_t InputConsumer::findTouchState(int32_t deviceId, int32_t source) const {
for (size_t i = 0; i < mTouchStates.size(); i++) {
const TouchState& touchState = mTouchStates.itemAt(i);
if (touchState.deviceId == deviceId && touchState.source == source) {
return i;
}
}
return -1;
}
void InputConsumer::initializeKeyEvent(KeyEvent* event, const InputMessage* msg) {
event->initialize(
msg->body.key.deviceId,
msg->body.key.source,
msg->body.key.displayId,
msg->body.key.action,
msg->body.key.flags,
msg->body.key.keyCode,
msg->body.key.scanCode,
msg->body.key.metaState,
msg->body.key.repeatCount,
msg->body.key.downTime,
msg->body.key.eventTime);
}
void InputConsumer::initializeMotionEvent(MotionEvent* event, const InputMessage* msg) {
uint32_t pointerCount = msg->body.motion.pointerCount;
PointerProperties pointerProperties[pointerCount];
PointerCoords pointerCoords[pointerCount];
for (uint32_t i = 0; i < pointerCount; i++) {
pointerProperties[i].copyFrom(msg->body.motion.pointers[i].properties);
pointerCoords[i].copyFrom(msg->body.motion.pointers[i].coords);
}
event->initialize(
msg->body.motion.deviceId,
msg->body.motion.source,
msg->body.motion.displayId,
msg->body.motion.action,
msg->body.motion.actionButton,
msg->body.motion.flags,
msg->body.motion.edgeFlags,
msg->body.motion.metaState,
msg->body.motion.buttonState,
msg->body.motion.classification,
msg->body.motion.xOffset,
msg->body.motion.yOffset,
msg->body.motion.xPrecision,
msg->body.motion.yPrecision,
msg->body.motion.downTime,
msg->body.motion.eventTime,
pointerCount,
pointerProperties,
pointerCoords);
}
void InputConsumer::addSample(MotionEvent* event, const InputMessage* msg) {
uint32_t pointerCount = msg->body.motion.pointerCount;
PointerCoords pointerCoords[pointerCount];
for (uint32_t i = 0; i < pointerCount; i++) {
pointerCoords[i].copyFrom(msg->body.motion.pointers[i].coords);
}
event->setMetaState(event->getMetaState() | msg->body.motion.metaState);
event->addSample(msg->body.motion.eventTime, pointerCoords);
}
bool InputConsumer::canAddSample(const Batch& batch, const InputMessage *msg) {
const InputMessage& head = batch.samples.itemAt(0);
uint32_t pointerCount = msg->body.motion.pointerCount;
if (head.body.motion.pointerCount != pointerCount
|| head.body.motion.action != msg->body.motion.action) {
return false;
}
for (size_t i = 0; i < pointerCount; i++) {
if (head.body.motion.pointers[i].properties
!= msg->body.motion.pointers[i].properties) {
return false;
}
}
return true;
}
ssize_t InputConsumer::findSampleNoLaterThan(const Batch& batch, nsecs_t time) {
size_t numSamples = batch.samples.size();
size_t index = 0;
while (index < numSamples
&& batch.samples.itemAt(index).body.motion.eventTime <= time) {
index += 1;
}
return ssize_t(index) - 1;
}
} // namespace android