| /* |
| * 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 _LIBINPUT_INPUT_TRANSPORT_H |
| #define _LIBINPUT_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/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. |
| * |
| * Note that this structure is used for IPCs so its layout must be identical |
| * on 64 and 32 bit processes. This is tested in StructLayout_test.cpp. |
| * |
| * Since the struct must be aligned to an 8-byte boundary, there could be uninitialized bytes |
| * in-between the defined fields. This padding data should be explicitly accounted for by adding |
| * "empty" fields into the struct. This data is memset to zero before sending the struct across |
| * the socket. Adding the explicit fields ensures that the memset is not optimized away by the |
| * compiler. When a new field is added to the struct, the corresponding change |
| * in StructLayout_test should be made. |
| */ |
| struct InputMessage { |
| enum { |
| TYPE_KEY = 1, |
| TYPE_MOTION = 2, |
| TYPE_FINISHED = 3, |
| }; |
| |
| struct Header { |
| uint32_t type; |
| // We don't need this field in order to align the body below but we |
| // leave it here because InputMessage::size() and other functions |
| // compute the size of this structure as sizeof(Header) + sizeof(Body). |
| uint32_t padding; |
| } header; |
| |
| // Body *must* be 8 byte aligned. |
| union Body { |
| struct Key { |
| uint32_t seq; |
| uint32_t empty1; |
| nsecs_t eventTime __attribute__((aligned(8))); |
| 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 __attribute__((aligned(8))); |
| |
| inline size_t size() const { |
| return sizeof(Key); |
| } |
| } key; |
| |
| struct Motion { |
| uint32_t seq; |
| uint32_t empty1; |
| nsecs_t eventTime __attribute__((aligned(8))); |
| int32_t deviceId; |
| int32_t source; |
| int32_t action; |
| int32_t actionButton; |
| int32_t flags; |
| int32_t metaState; |
| int32_t buttonState; |
| int32_t edgeFlags; |
| nsecs_t downTime __attribute__((aligned(8))); |
| float xOffset; |
| float yOffset; |
| float xPrecision; |
| float yPrecision; |
| uint32_t pointerCount; |
| uint32_t empty2; |
| // Note that PointerCoords requires 8 byte alignment. |
| 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; |
| } __attribute__((aligned(8))) body; |
| |
| bool isValid(size_t actualSize) const; |
| size_t size() const; |
| void getSanitizedCopy(InputMessage* msg) 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 actionButton, |
| 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, |
| uint32_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 (uint32_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 // _LIBINPUT_INPUT_TRANSPORT_H |