The Tor Browser: comparison widget/gonk/libui/InputTransport.h

--1:000000000000
+:2882c8a092ae
+/*
+* Copyright (C) 2010 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.
+*/
+#ifndef _ANDROIDFW_INPUT_TRANSPORT_H
+#define _ANDROIDFW_INPUT_TRANSPORT_H
+/**
+* Native input transport.
+*
+* The InputChannel provides a mechanism for exchanging InputMessage structures across processes.
+*
+* The InputPublisher and InputConsumer each handle one end-point of an input channel.
+* The InputPublisher is used by the input dispatcher to send events to the application.
+* The InputConsumer is used by the application to receive events from the input dispatcher.
+*/
+#include "Input.h"
+#include <utils/Errors.h>
+#include <utils/Timers.h>
+#include <utils/RefBase.h>
+#include <utils/String8.h>
+#include <utils/Vector.h>
+#include <utils/BitSet.h>
+namespace android {
+/*
+* Intermediate representation used to send input events and related signals.
+*/
+struct InputMessage {
+enum {
+TYPE_KEY = 1,
+TYPE_MOTION = 2,
+TYPE_FINISHED = 3,
+};
+struct Header {
+uint32_t type;
+uint32_t padding; // 8 byte alignment for the body that follows
+} header;
+union Body {
+struct Key {
+uint32_t seq;
+nsecs_t eventTime;
+int32_t deviceId;
+int32_t source;
+int32_t action;
+int32_t flags;
+int32_t keyCode;
+int32_t scanCode;
+int32_t metaState;
+int32_t repeatCount;
+nsecs_t downTime;
+inline size_t size() const {
+return sizeof(Key);
+}
+} key;
+struct Motion {
+uint32_t seq;
+nsecs_t eventTime;
+int32_t deviceId;
+int32_t source;
+int32_t action;
+int32_t flags;
+int32_t metaState;
+int32_t buttonState;
+int32_t edgeFlags;
+nsecs_t downTime;
+float xOffset;
+float yOffset;
+float xPrecision;
+float yPrecision;
+size_t pointerCount;
+struct Pointer {
+PointerProperties properties;
+PointerCoords coords;
+} pointers[MAX_POINTERS];
+int32_t getActionId() const {
+uint32_t index = (action & AMOTION_EVENT_ACTION_POINTER_INDEX_MASK)
+>> AMOTION_EVENT_ACTION_POINTER_INDEX_SHIFT;
+return pointers[index].properties.id;
+}
+inline size_t size() const {
+return sizeof(Motion) - sizeof(Pointer) * MAX_POINTERS
++ sizeof(Pointer) * pointerCount;
+}
+} motion;
+struct Finished {
+uint32_t seq;
+bool handled;
+inline size_t size() const {
+return sizeof(Finished);
+}
+} finished;
+} body;
+bool isValid(size_t actualSize) const;
+size_t size() const;
+};
+/*
+* An input channel consists of a local unix domain socket used to send and receive
+* input messages across processes.  Each channel has a descriptive name for debugging purposes.
+*
+* Each endpoint has its own InputChannel object that specifies its file descriptor.
+*
+* The input channel is closed when all references to it are released.
+*/
+class InputChannel : public RefBase {
+protected:
+virtual ~InputChannel();
+public:
+InputChannel(const String8& name, int fd);
+/* Creates a pair of input channels.
+*
+* Returns OK on success.
+*/
+static status_t openInputChannelPair(const String8& name,
+sp<InputChannel>& outServerChannel, sp<InputChannel>& outClientChannel);
+inline String8 getName() const { return mName; }
+inline int getFd() const { return mFd; }
+/* Sends a message to the other endpoint.
+*
+* If the channel is full then the message is guaranteed not to have been sent at all.
+* Try again after the consumer has sent a finished signal indicating that it has
+* consumed some of the pending messages from the channel.
+*
+* Returns OK on success.
+* Returns WOULD_BLOCK if the channel is full.
+* Returns DEAD_OBJECT if the channel's peer has been closed.
+* Other errors probably indicate that the channel is broken.
+*/
+status_t sendMessage(const InputMessage* msg);
+/* Receives a message sent by the other endpoint.
+*
+* If there is no message present, try again after poll() indicates that the fd
+* is readable.
+*
+* Returns OK on success.
+* Returns WOULD_BLOCK if there is no message present.
+* Returns DEAD_OBJECT if the channel's peer has been closed.
+* Other errors probably indicate that the channel is broken.
+*/
+status_t receiveMessage(InputMessage* msg);
+/* Returns a new object that has a duplicate of this channel's fd. */
+sp<InputChannel> dup() const;
+private:
+String8 mName;
+int mFd;
+};
+/*
+* Publishes input events to an input channel.
+*/
+class InputPublisher {
+public:
+/* Creates a publisher associated with an input channel. */
+explicit InputPublisher(const sp<InputChannel>& channel);
+/* Destroys the publisher and releases its input channel. */
+~InputPublisher();
+/* Gets the underlying input channel. */
+inline sp<InputChannel> getChannel() { return mChannel; }
+/* Publishes a key event to the input channel.
+*
+* Returns OK on success.
+* Returns WOULD_BLOCK if the channel is full.
+* Returns DEAD_OBJECT if the channel's peer has been closed.
+* Returns BAD_VALUE if seq is 0.
+* Other errors probably indicate that the channel is broken.
+*/
+status_t publishKeyEvent(
+uint32_t seq,
+int32_t deviceId,
+int32_t source,
+int32_t action,
+int32_t flags,
+int32_t keyCode,
+int32_t scanCode,
+int32_t metaState,
+int32_t repeatCount,
+nsecs_t downTime,
+nsecs_t eventTime);
+/* Publishes a motion event to the input channel.
+*
+* Returns OK on success.
+* Returns WOULD_BLOCK if the channel is full.
+* Returns DEAD_OBJECT if the channel's peer has been closed.
+* Returns BAD_VALUE if seq is 0 or if pointerCount is less than 1 or greater than MAX_POINTERS.
+* Other errors probably indicate that the channel is broken.
+*/
+status_t publishMotionEvent(
+uint32_t seq,
+int32_t deviceId,
+int32_t source,
+int32_t action,
+int32_t flags,
+int32_t edgeFlags,
+int32_t metaState,
+int32_t buttonState,
+float xOffset,
+float yOffset,
+float xPrecision,
+float yPrecision,
+nsecs_t downTime,
+nsecs_t eventTime,
+size_t pointerCount,
+const PointerProperties* pointerProperties,
+const PointerCoords* pointerCoords);
+/* Receives the finished signal from the consumer in reply to the original dispatch signal.
+* If a signal was received, returns the message sequence number,
+* and whether the consumer handled the message.
+*
+* The returned sequence number is never 0 unless the operation failed.
+*
+* Returns OK on success.
+* Returns WOULD_BLOCK if there is no signal present.
+* Returns DEAD_OBJECT if the channel's peer has been closed.
+* Other errors probably indicate that the channel is broken.
+*/
+status_t receiveFinishedSignal(uint32_t* outSeq, bool* outHandled);
+private:
+sp<InputChannel> mChannel;
+};
+/*
+* Consumes input events from an input channel.
+*/
+class InputConsumer {
+public:
+/* Creates a consumer associated with an input channel. */
+explicit InputConsumer(const sp<InputChannel>& channel);
+/* Destroys the consumer and releases its input channel. */
+~InputConsumer();
+/* Gets the underlying input channel. */
+inline sp<InputChannel> getChannel() { return mChannel; }
+/* Consumes an input event from the input channel and copies its contents into
+* an InputEvent object created using the specified factory.
+*
+* Tries to combine a series of move events into larger batches whenever possible.
+*
+* If consumeBatches is false, then defers consuming pending batched events if it
+* is possible for additional samples to be added to them later.  Call hasPendingBatch()
+* to determine whether a pending batch is available to be consumed.
+*
+* If consumeBatches is true, then events are still batched but they are consumed
+* immediately as soon as the input channel is exhausted.
+*
+* The frameTime parameter specifies the time when the current display frame started
+* rendering in the CLOCK_MONOTONIC time base, or -1 if unknown.
+*
+* The returned sequence number is never 0 unless the operation failed.
+*
+* Returns OK on success.
+* Returns WOULD_BLOCK if there is no event present.
+* Returns DEAD_OBJECT if the channel's peer has been closed.
+* Returns NO_MEMORY if the event could not be created.
+* Other errors probably indicate that the channel is broken.
+*/
+status_t consume(InputEventFactoryInterface* factory, bool consumeBatches,
+nsecs_t frameTime, uint32_t* outSeq, InputEvent** outEvent);
+/* Sends a finished signal to the publisher to inform it that the message
+* with the specified sequence number has finished being process and whether
+* the message was handled by the consumer.
+*
+* Returns OK on success.
+* Returns BAD_VALUE if seq is 0.
+* Other errors probably indicate that the channel is broken.
+*/
+status_t sendFinishedSignal(uint32_t seq, bool handled);
+/* Returns true if there is a deferred event waiting.
+*
+* Should be called after calling consume() to determine whether the consumer
+* has a deferred event to be processed.  Deferred events are somewhat special in
+* that they have already been removed from the input channel.  If the input channel
+* becomes empty, the client may need to do extra work to ensure that it processes
+* the deferred event despite the fact that the input channel's file descriptor
+* is not readable.
+*
+* One option is simply to call consume() in a loop until it returns WOULD_BLOCK.
+* This guarantees that all deferred events will be processed.
+*
+* Alternately, the caller can call hasDeferredEvent() to determine whether there is
+* a deferred event waiting and then ensure that its event loop wakes up at least
+* one more time to consume the deferred event.
+*/
+bool hasDeferredEvent() const;
+/* Returns true if there is a pending batch.
+*
+* Should be called after calling consume() with consumeBatches == false to determine
+* whether consume() should be called again later on with consumeBatches == true.
+*/
+bool hasPendingBatch() const;
+private:
+// True if touch resampling is enabled.
+const bool mResampleTouch;
+// The input channel.
+sp<InputChannel> mChannel;
+// The current input message.
+InputMessage mMsg;
+// True if mMsg contains a valid input message that was deferred from the previous
+// call to consume and that still needs to be handled.
+bool mMsgDeferred;
+// Batched motion events per device and source.
+struct Batch {
+Vector<InputMessage> samples;
+};
+Vector<Batch> mBatches;
+// Touch state per device and source, only for sources of class pointer.
+struct History {
+nsecs_t eventTime;
+BitSet32 idBits;
+int32_t idToIndex[MAX_POINTER_ID + 1];
+PointerCoords pointers[MAX_POINTERS];
+void initializeFrom(const InputMessage* msg) {
+eventTime = msg->body.motion.eventTime;
+idBits.clear();
+for (size_t i = 0; i < msg->body.motion.pointerCount; i++) {
+uint32_t id = msg->body.motion.pointers[i].properties.id;
+idBits.markBit(id);
+idToIndex[id] = i;
+pointers[i].copyFrom(msg->body.motion.pointers[i].coords);
+}
+}
+const PointerCoords& getPointerById(uint32_t id) const {
+return pointers[idToIndex[id]];
+}
+};
+struct TouchState {
+int32_t deviceId;
+int32_t source;
+size_t historyCurrent;
+size_t historySize;
+History history[2];
+History lastResample;
+void initialize(int32_t deviceId, int32_t source) {
+this->deviceId = deviceId;
+this->source = source;
+historyCurrent = 0;
+historySize = 0;
+lastResample.eventTime = 0;
+lastResample.idBits.clear();
+}
+void addHistory(const InputMessage* msg) {
+historyCurrent ^= 1;
+if (historySize < 2) {
+historySize += 1;
+}
+history[historyCurrent].initializeFrom(msg);
+}
+const History* getHistory(size_t index) const {
+return &history[(historyCurrent + index) & 1];
+}
+};
+Vector<TouchState> mTouchStates;
+// Chain of batched sequence numbers.  When multiple input messages are combined into
+// a batch, we append a record here that associates the last sequence number in the
+// batch with the previous one.  When the finished signal is sent, we traverse the
+// chain to individually finish all input messages that were part of the batch.
+struct SeqChain {
+uint32_t seq;   // sequence number of batched input message
+uint32_t chain; // sequence number of previous batched input message
+};
+Vector<SeqChain> mSeqChains;
+status_t consumeBatch(InputEventFactoryInterface* factory,
+nsecs_t frameTime, uint32_t* outSeq, InputEvent** outEvent);
+status_t consumeSamples(InputEventFactoryInterface* factory,
+Batch& batch, size_t count, uint32_t* outSeq, InputEvent** outEvent);
+void updateTouchState(InputMessage* msg);
+void rewriteMessage(const TouchState& state, InputMessage* msg);
+void resampleTouchState(nsecs_t frameTime, MotionEvent* event,
+const InputMessage *next);
+ssize_t findBatch(int32_t deviceId, int32_t source) const;
+ssize_t findTouchState(int32_t deviceId, int32_t source) const;
+status_t sendUnchainedFinishedSignal(uint32_t seq, bool handled);
+static void initializeKeyEvent(KeyEvent* event, const InputMessage* msg);
+static void initializeMotionEvent(MotionEvent* event, const InputMessage* msg);
+static void addSample(MotionEvent* event, const InputMessage* msg);
+static bool canAddSample(const Batch& batch, const InputMessage* msg);
+static ssize_t findSampleNoLaterThan(const Batch& batch, nsecs_t time);
+static bool shouldResampleTool(int32_t toolType);
+static bool isTouchResamplingEnabled();
+};
+} // namespace android
+#endif // _ANDROIDFW_INPUT_TRANSPORT_H

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comparison: widget/gonk/libui/InputTransport.h

widget/gonk/libui/InputTransport.h