/* * 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 _UI_INPUT_DISPATCHER_H #define _UI_INPUT_DISPATCHER_H #include #include #include #include #include #include #include #include #include #include #include #include namespace android { /* * Constants used to report the outcome of input event injection. */ enum { /* (INTERNAL USE ONLY) Specifies that injection is pending and its outcome is unknown. */ INPUT_EVENT_INJECTION_PENDING = -1, /* Injection succeeded. */ INPUT_EVENT_INJECTION_SUCCEEDED = 0, /* Injection failed because the injector did not have permission to inject * into the application with input focus. */ INPUT_EVENT_INJECTION_PERMISSION_DENIED = 1, /* Injection failed because there were no available input targets. */ INPUT_EVENT_INJECTION_FAILED = 2, /* Injection failed due to a timeout. */ INPUT_EVENT_INJECTION_TIMED_OUT = 3 }; /* * Constants used to determine the input event injection synchronization mode. */ enum { /* Injection is asynchronous and is assumed always to be successful. */ INPUT_EVENT_INJECTION_SYNC_NONE = 0, /* Waits for previous events to be dispatched so that the input dispatcher can determine * whether input event injection willbe permitted based on the current input focus. * Does not wait for the input event to finish processing. */ INPUT_EVENT_INJECTION_SYNC_WAIT_FOR_RESULT = 1, /* Waits for the input event to be completely processed. */ INPUT_EVENT_INJECTION_SYNC_WAIT_FOR_FINISHED = 2, }; /* * An input target specifies how an input event is to be dispatched to a particular window * including the window's input channel, control flags, a timeout, and an X / Y offset to * be added to input event coordinates to compensate for the absolute position of the * window area. */ struct InputTarget { enum { /* This flag indicates that subsequent event delivery should be held until the * current event is delivered to this target or a timeout occurs. */ FLAG_SYNC = 0x01, /* This flag indicates that a MotionEvent with AMOTION_EVENT_ACTION_DOWN falls outside * of the area of this target and so should instead be delivered as an * AMOTION_EVENT_ACTION_OUTSIDE to this target. */ FLAG_OUTSIDE = 0x02, /* This flag indicates that a KeyEvent or MotionEvent is being canceled. * In the case of a key event, it should be delivered with flag * AKEY_EVENT_FLAG_CANCELED set. * In the case of a motion event, it should be delivered with action * AMOTION_EVENT_ACTION_CANCEL instead. */ FLAG_CANCEL = 0x04, /* This flag indicates that the target of a MotionEvent is partly or wholly * obscured by another visible window above it. The motion event should be * delivered with flag AMOTION_EVENT_FLAG_WINDOW_IS_OBSCURED. */ FLAG_WINDOW_IS_OBSCURED = 0x08, }; // The input channel to be targeted. sp inputChannel; // Flags for the input target. int32_t flags; // The timeout for event delivery to this target in nanoseconds. Or -1 if none. nsecs_t timeout; // The x and y offset to add to a MotionEvent as it is delivered. // (ignored for KeyEvents) float xOffset, yOffset; }; /* * Input dispatcher policy interface. * * The input reader policy is used by the input reader to interact with the Window Manager * and other system components. * * The actual implementation is partially supported by callbacks into the DVM * via JNI. This interface is also mocked in the unit tests. */ class InputDispatcherPolicyInterface : public virtual RefBase { protected: InputDispatcherPolicyInterface() { } virtual ~InputDispatcherPolicyInterface() { } public: /* Notifies the system that a configuration change has occurred. */ virtual void notifyConfigurationChanged(nsecs_t when) = 0; /* Notifies the system that an input channel is unrecoverably broken. */ virtual void notifyInputChannelBroken(const sp& inputChannel) = 0; /* Notifies the system that an input channel is not responding. * Returns true and a new timeout value if the dispatcher should keep waiting. * Otherwise returns false. */ virtual bool notifyInputChannelANR(const sp& inputChannel, nsecs_t& outNewTimeout) = 0; /* Notifies the system that an input channel recovered from ANR. */ virtual void notifyInputChannelRecoveredFromANR(const sp& inputChannel) = 0; /* Gets the key repeat initial timeout or -1 if automatic key repeating is disabled. */ virtual nsecs_t getKeyRepeatTimeout() = 0; /* Gets the key repeat inter-key delay. */ virtual nsecs_t getKeyRepeatDelay() = 0; /* Waits for key event input targets to become available. * If the event is being injected, injectorPid and injectorUid should specify the * process id and used id of the injecting application, otherwise they should both * be -1. * Returns one of the INPUT_EVENT_INJECTION_XXX constants. */ virtual int32_t waitForKeyEventTargets(KeyEvent* keyEvent, uint32_t policyFlags, int32_t injectorPid, int32_t injectorUid, Vector& outTargets) = 0; /* Waits for motion event targets to become available. * If the event is being injected, injectorPid and injectorUid should specify the * process id and used id of the injecting application, otherwise they should both * be -1. * Returns one of the INPUT_EVENT_INJECTION_XXX constants. */ virtual int32_t waitForMotionEventTargets(MotionEvent* motionEvent, uint32_t policyFlags, int32_t injectorPid, int32_t injectorUid, Vector& outTargets) = 0; /* Gets the maximum suggested event delivery rate per second. * This value is used to throttle motion event movement actions on a per-device * basis. It is not intended to be a hard limit. */ virtual int32_t getMaxEventsPerSecond() = 0; }; /* Notifies the system about input events generated by the input reader. * The dispatcher is expected to be mostly asynchronous. */ class InputDispatcherInterface : public virtual RefBase { protected: InputDispatcherInterface() { } virtual ~InputDispatcherInterface() { } public: /* Runs a single iteration of the dispatch loop. * Nominally processes one queued event, a timeout, or a response from an input consumer. * * This method should only be called on the input dispatcher thread. */ virtual void dispatchOnce() = 0; /* Notifies the dispatcher about new events. * * These methods should only be called on the input reader thread. */ virtual void notifyConfigurationChanged(nsecs_t eventTime) = 0; virtual void notifyAppSwitchComing(nsecs_t eventTime) = 0; virtual void notifyKey(nsecs_t eventTime, int32_t deviceId, int32_t source, uint32_t policyFlags, int32_t action, int32_t flags, int32_t keyCode, int32_t scanCode, int32_t metaState, nsecs_t downTime) = 0; virtual void notifyMotion(nsecs_t eventTime, int32_t deviceId, int32_t source, uint32_t policyFlags, int32_t action, int32_t flags, int32_t metaState, int32_t edgeFlags, uint32_t pointerCount, const int32_t* pointerIds, const PointerCoords* pointerCoords, float xPrecision, float yPrecision, nsecs_t downTime) = 0; /* Injects an input event and optionally waits for sync. * The synchronization mode determines whether the method blocks while waiting for * input injection to proceed. * Returns one of the INPUT_EVENT_INJECTION_XXX constants. * * This method may be called on any thread (usually by the input manager). */ virtual int32_t injectInputEvent(const InputEvent* event, int32_t injectorPid, int32_t injectorUid, int32_t syncMode, int32_t timeoutMillis) = 0; /* Preempts input dispatch in progress by making pending synchronous * dispatches asynchronous instead. This method is generally called during a focus * transition from one application to the next so as to enable the new application * to start receiving input as soon as possible without having to wait for the * old application to finish up. * * This method may be called on any thread (usually by the input manager). */ virtual void preemptInputDispatch() = 0; /* Registers or unregister input channels that may be used as targets for input events. * * These methods may be called on any thread (usually by the input manager). */ virtual status_t registerInputChannel(const sp& inputChannel) = 0; virtual status_t unregisterInputChannel(const sp& inputChannel) = 0; }; /* Dispatches events to input targets. Some functions of the input dispatcher, such as * identifying input targets, are controlled by a separate policy object. * * IMPORTANT INVARIANT: * Because the policy can potentially block or cause re-entrance into the input dispatcher, * the input dispatcher never calls into the policy while holding its internal locks. * The implementation is also carefully designed to recover from scenarios such as an * input channel becoming unregistered while identifying input targets or processing timeouts. * * Methods marked 'Locked' must be called with the lock acquired. * * Methods marked 'LockedInterruptible' must be called with the lock acquired but * may during the course of their execution release the lock, call into the policy, and * then reacquire the lock. The caller is responsible for recovering gracefully. * * A 'LockedInterruptible' method may called a 'Locked' method, but NOT vice-versa. */ class InputDispatcher : public InputDispatcherInterface { protected: virtual ~InputDispatcher(); public: explicit InputDispatcher(const sp& policy); virtual void dispatchOnce(); virtual void notifyConfigurationChanged(nsecs_t eventTime); virtual void notifyAppSwitchComing(nsecs_t eventTime); virtual void notifyKey(nsecs_t eventTime, int32_t deviceId, int32_t source, uint32_t policyFlags, int32_t action, int32_t flags, int32_t keyCode, int32_t scanCode, int32_t metaState, nsecs_t downTime); virtual void notifyMotion(nsecs_t eventTime, int32_t deviceId, int32_t source, uint32_t policyFlags, int32_t action, int32_t flags, int32_t metaState, int32_t edgeFlags, uint32_t pointerCount, const int32_t* pointerIds, const PointerCoords* pointerCoords, float xPrecision, float yPrecision, nsecs_t downTime); virtual int32_t injectInputEvent(const InputEvent* event, int32_t injectorPid, int32_t injectorUid, int32_t syncMode, int32_t timeoutMillis); virtual void preemptInputDispatch(); virtual status_t registerInputChannel(const sp& inputChannel); virtual status_t unregisterInputChannel(const sp& inputChannel); private: template struct Link { T* next; T* prev; }; struct EventEntry : Link { enum { TYPE_SENTINEL, TYPE_CONFIGURATION_CHANGED, TYPE_KEY, TYPE_MOTION }; int32_t refCount; int32_t type; nsecs_t eventTime; int32_t injectionResult; // initially INPUT_EVENT_INJECTION_PENDING bool injectionIsAsync; // set to true if injection is not waiting for the result int32_t injectorPid; // -1 if not injected int32_t injectorUid; // -1 if not injected bool dispatchInProgress; // initially false, set to true while dispatching int32_t pendingSyncDispatches; // the number of synchronous dispatches in progress inline bool isInjected() { return injectorPid >= 0; } }; struct ConfigurationChangedEntry : EventEntry { }; struct KeyEntry : EventEntry { int32_t deviceId; int32_t source; uint32_t policyFlags; int32_t action; int32_t flags; int32_t keyCode; int32_t scanCode; int32_t metaState; int32_t repeatCount; nsecs_t downTime; }; struct MotionSample { MotionSample* next; nsecs_t eventTime; PointerCoords pointerCoords[MAX_POINTERS]; }; struct MotionEntry : EventEntry { int32_t deviceId; int32_t source; uint32_t policyFlags; int32_t action; int32_t flags; int32_t metaState; int32_t edgeFlags; float xPrecision; float yPrecision; nsecs_t downTime; uint32_t pointerCount; int32_t pointerIds[MAX_POINTERS]; // Linked list of motion samples associated with this motion event. MotionSample firstSample; MotionSample* lastSample; uint32_t countSamples() const; }; // Tracks the progress of dispatching a particular event to a particular connection. struct DispatchEntry : Link { EventEntry* eventEntry; // the event to dispatch int32_t targetFlags; float xOffset; float yOffset; nsecs_t timeout; // True if dispatch has started. bool inProgress; // For motion events: // Pointer to the first motion sample to dispatch in this cycle. // Usually NULL to indicate that the list of motion samples begins at // MotionEntry::firstSample. Otherwise, some samples were dispatched in a previous // cycle and this pointer indicates the location of the first remainining sample // to dispatch during the current cycle. MotionSample* headMotionSample; // Pointer to a motion sample to dispatch in the next cycle if the dispatcher was // unable to send all motion samples during this cycle. On the next cycle, // headMotionSample will be initialized to tailMotionSample and tailMotionSample // will be set to NULL. MotionSample* tailMotionSample; inline bool isSyncTarget() { return targetFlags & InputTarget::FLAG_SYNC; } }; // A command entry captures state and behavior for an action to be performed in the // dispatch loop after the initial processing has taken place. It is essentially // a kind of continuation used to postpone sensitive policy interactions to a point // in the dispatch loop where it is safe to release the lock (generally after finishing // the critical parts of the dispatch cycle). // // The special thing about commands is that they can voluntarily release and reacquire // the dispatcher lock at will. Initially when the command starts running, the // dispatcher lock is held. However, if the command needs to call into the policy to // do some work, it can release the lock, do the work, then reacquire the lock again // before returning. // // This mechanism is a bit clunky but it helps to preserve the invariant that the dispatch // never calls into the policy while holding its lock. // // Commands are implicitly 'LockedInterruptible'. struct CommandEntry; typedef void (InputDispatcher::*Command)(CommandEntry* commandEntry); class Connection; struct CommandEntry : Link { CommandEntry(); ~CommandEntry(); Command command; // parameters for the command (usage varies by command) sp connection; }; // Generic queue implementation. template struct Queue { T head; T tail; inline Queue() { head.prev = NULL; head.next = & tail; tail.prev = & head; tail.next = NULL; } inline bool isEmpty() { return head.next == & tail; } inline void enqueueAtTail(T* entry) { T* last = tail.prev; last->next = entry; entry->prev = last; entry->next = & tail; tail.prev = entry; } inline void enqueueAtHead(T* entry) { T* first = head.next; head.next = entry; entry->prev = & head; entry->next = first; first->prev = entry; } inline void dequeue(T* entry) { entry->prev->next = entry->next; entry->next->prev = entry->prev; } inline T* dequeueAtHead() { T* first = head.next; dequeue(first); return first; } }; /* Allocates queue entries and performs reference counting as needed. */ class Allocator { public: Allocator(); ConfigurationChangedEntry* obtainConfigurationChangedEntry(nsecs_t eventTime); KeyEntry* obtainKeyEntry(nsecs_t eventTime, int32_t deviceId, int32_t source, uint32_t policyFlags, int32_t action, int32_t flags, int32_t keyCode, int32_t scanCode, int32_t metaState, int32_t repeatCount, nsecs_t downTime); MotionEntry* obtainMotionEntry(nsecs_t eventTime, int32_t deviceId, int32_t source, uint32_t policyFlags, int32_t action, int32_t flags, int32_t metaState, int32_t edgeFlags, float xPrecision, float yPrecision, nsecs_t downTime, uint32_t pointerCount, const int32_t* pointerIds, const PointerCoords* pointerCoords); DispatchEntry* obtainDispatchEntry(EventEntry* eventEntry); CommandEntry* obtainCommandEntry(Command command); void releaseEventEntry(EventEntry* entry); void releaseConfigurationChangedEntry(ConfigurationChangedEntry* entry); void releaseKeyEntry(KeyEntry* entry); void releaseMotionEntry(MotionEntry* entry); void releaseDispatchEntry(DispatchEntry* entry); void releaseCommandEntry(CommandEntry* entry); void appendMotionSample(MotionEntry* motionEntry, nsecs_t eventTime, const PointerCoords* pointerCoords); private: Pool mConfigurationChangeEntryPool; Pool mKeyEntryPool; Pool mMotionEntryPool; Pool mMotionSamplePool; Pool mDispatchEntryPool; Pool mCommandEntryPool; void initializeEventEntry(EventEntry* entry, int32_t type, nsecs_t eventTime); }; /* Manages the dispatch state associated with a single input channel. */ class Connection : public RefBase { protected: virtual ~Connection(); public: enum Status { // Everything is peachy. STATUS_NORMAL, // An unrecoverable communication error has occurred. STATUS_BROKEN, // The client is not responding. STATUS_NOT_RESPONDING, // The input channel has been unregistered. STATUS_ZOMBIE }; Status status; sp inputChannel; InputPublisher inputPublisher; Queue outboundQueue; nsecs_t nextTimeoutTime; // next timeout time (LONG_LONG_MAX if none) nsecs_t lastEventTime; // the time when the event was originally captured nsecs_t lastDispatchTime; // the time when the last event was dispatched nsecs_t lastANRTime; // the time when the last ANR was recorded explicit Connection(const sp& inputChannel); inline const char* getInputChannelName() const { return inputChannel->getName().string(); } const char* getStatusLabel() const; // Finds a DispatchEntry in the outbound queue associated with the specified event. // Returns NULL if not found. DispatchEntry* findQueuedDispatchEntryForEvent(const EventEntry* eventEntry) const; // Determine whether this connection has a pending synchronous dispatch target. // Since there can only ever be at most one such target at a time, if there is one, // it must be at the tail because nothing else can be enqueued after it. inline bool hasPendingSyncTarget() { return ! outboundQueue.isEmpty() && outboundQueue.tail.prev->isSyncTarget(); } // Gets the time since the current event was originally obtained from the input driver. inline double getEventLatencyMillis(nsecs_t currentTime) { return (currentTime - lastEventTime) / 1000000.0; } // Gets the time since the current event entered the outbound dispatch queue. inline double getDispatchLatencyMillis(nsecs_t currentTime) { return (currentTime - lastDispatchTime) / 1000000.0; } // Gets the time since the current event ANR was declared, if applicable. inline double getANRLatencyMillis(nsecs_t currentTime) { return (currentTime - lastANRTime) / 1000000.0; } status_t initialize(); void setNextTimeoutTime(nsecs_t currentTime, nsecs_t timeout); }; sp mPolicy; Mutex mLock; Allocator mAllocator; sp mPollLoop; Queue mInboundQueue; Queue mCommandQueue; // All registered connections mapped by receive pipe file descriptor. KeyedVector > mConnectionsByReceiveFd; ssize_t getConnectionIndex(const sp& inputChannel); // Active connections are connections that have a non-empty outbound queue. // We don't use a ref-counted pointer here because we explicitly abort connections // during unregistration which causes the connection's outbound queue to be cleared // and the connection itself to be deactivated. Vector mActiveConnections; // List of connections that have timed out. Only used by dispatchOnce() // We don't use a ref-counted pointer here because it is not possible for a connection // to be unregistered while processing timed out connections since we hold the lock for // the duration. Vector mTimedOutConnections; // Preallocated key and motion event objects used only to ask the input dispatcher policy // for the targets of an event that is to be dispatched. KeyEvent mReusableKeyEvent; MotionEvent mReusableMotionEvent; // The input targets that were most recently identified for dispatch. // If there is a synchronous event dispatch in progress, the current input targets will // remain unchanged until the dispatch has completed or been aborted. Vector mCurrentInputTargets; bool mCurrentInputTargetsValid; // false while targets are being recomputed // Event injection and synchronization. Condition mInjectionResultAvailableCondition; EventEntry* createEntryFromInputEventLocked(const InputEvent* event); void setInjectionResultLocked(EventEntry* entry, int32_t injectionResult); Condition mInjectionSyncFinishedCondition; void decrementPendingSyncDispatchesLocked(EventEntry* entry); // Throttling state. struct ThrottleState { nsecs_t minTimeBetweenEvents; nsecs_t lastEventTime; int32_t lastDeviceId; uint32_t lastSource; uint32_t originalSampleCount; // only collected during debugging } mThrottleState; // Key repeat tracking. // XXX Move this up to the input reader instead. struct KeyRepeatState { KeyEntry* lastKeyEntry; // or null if no repeat nsecs_t nextRepeatTime; } mKeyRepeatState; void resetKeyRepeatLocked(); // Deferred command processing. bool runCommandsLockedInterruptible(); CommandEntry* postCommandLocked(Command command); // Process events that have just been dequeued from the head of the input queue. void processConfigurationChangedLockedInterruptible( nsecs_t currentTime, ConfigurationChangedEntry* entry); void processKeyLockedInterruptible( nsecs_t currentTime, KeyEntry* entry, nsecs_t keyRepeatTimeout); void processKeyRepeatLockedInterruptible( nsecs_t currentTime, nsecs_t keyRepeatTimeout); void processMotionLockedInterruptible( nsecs_t currentTime, MotionEntry* entry); // Identify input targets for an event and dispatch to them. void identifyInputTargetsAndDispatchKeyLockedInterruptible( nsecs_t currentTime, KeyEntry* entry); void identifyInputTargetsAndDispatchMotionLockedInterruptible( nsecs_t currentTime, MotionEntry* entry); void dispatchEventToCurrentInputTargetsLocked( nsecs_t currentTime, EventEntry* entry, bool resumeWithAppendedMotionSample); // Manage the dispatch cycle for a single connection. // These methods are deliberately not Interruptible because doing all of the work // with the mutex held makes it easier to ensure that connection invariants are maintained. // If needed, the methods post commands to run later once the critical bits are done. void prepareDispatchCycleLocked(nsecs_t currentTime, const sp& connection, EventEntry* eventEntry, const InputTarget* inputTarget, bool resumeWithAppendedMotionSample); void startDispatchCycleLocked(nsecs_t currentTime, const sp& connection); void finishDispatchCycleLocked(nsecs_t currentTime, const sp& connection); void timeoutDispatchCycleLocked(nsecs_t currentTime, const sp& connection); void resumeAfterTimeoutDispatchCycleLocked(nsecs_t currentTime, const sp& connection, nsecs_t newTimeout); void abortDispatchCycleLocked(nsecs_t currentTime, const sp& connection, bool broken); static bool handleReceiveCallback(int receiveFd, int events, void* data); // Add or remove a connection to the mActiveConnections vector. void activateConnectionLocked(Connection* connection); void deactivateConnectionLocked(Connection* connection); // Interesting events that we might like to log or tell the framework about. void onDispatchCycleStartedLocked( nsecs_t currentTime, const sp& connection); void onDispatchCycleFinishedLocked( nsecs_t currentTime, const sp& connection, bool recoveredFromANR); void onDispatchCycleANRLocked( nsecs_t currentTime, const sp& connection); void onDispatchCycleBrokenLocked( nsecs_t currentTime, const sp& connection); // Outbound policy interactions. void doNotifyInputChannelBrokenLockedInterruptible(CommandEntry* commandEntry); void doNotifyInputChannelANRLockedInterruptible(CommandEntry* commandEntry); void doNotifyInputChannelRecoveredFromANRLockedInterruptible(CommandEntry* commandEntry); }; /* Enqueues and dispatches input events, endlessly. */ class InputDispatcherThread : public Thread { public: explicit InputDispatcherThread(const sp& dispatcher); ~InputDispatcherThread(); private: virtual bool threadLoop(); sp mDispatcher; }; } // namespace android #endif // _UI_INPUT_DISPATCHER_PRIV_H