1/*
2 * Copyright (C) 2011 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#define LOG_TAG "InputEventReceiver"
18
19//#define LOG_NDEBUG 0
20
21// Log debug messages about the dispatch cycle.
22#define DEBUG_DISPATCH_CYCLE 0
23
24
25#include "JNIHelp.h"
26
27#include <android_runtime/AndroidRuntime.h>
28#include <utils/Log.h>
29#include <utils/Looper.h>
30#include <utils/threads.h>
31#include <androidfw/InputTransport.h>
32#include "android_os_MessageQueue.h"
33#include "android_view_InputChannel.h"
34#include "android_view_KeyEvent.h"
35#include "android_view_MotionEvent.h"
36
37namespace android {
38
39static struct {
40    jclass clazz;
41
42    jmethodID dispatchInputEvent;
43    jmethodID dispatchBatchedInputEventPending;
44} gInputEventReceiverClassInfo;
45
46
47class NativeInputEventReceiver : public LooperCallback {
48public:
49    NativeInputEventReceiver(JNIEnv* env,
50            jobject receiverObj, const sp<InputChannel>& inputChannel,
51            const sp<MessageQueue>& messageQueue);
52
53    status_t initialize();
54    void dispose();
55    status_t finishInputEvent(uint32_t seq, bool handled);
56    status_t consumeEvents(JNIEnv* env, bool consumeBatches, nsecs_t frameTime);
57
58protected:
59    virtual ~NativeInputEventReceiver();
60
61private:
62    jobject mReceiverObjGlobal;
63    InputConsumer mInputConsumer;
64    sp<MessageQueue> mMessageQueue;
65    PreallocatedInputEventFactory mInputEventFactory;
66    bool mBatchedInputEventPending;
67
68    const char* getInputChannelName() {
69        return mInputConsumer.getChannel()->getName().string();
70    }
71
72    virtual int handleEvent(int receiveFd, int events, void* data);
73};
74
75
76NativeInputEventReceiver::NativeInputEventReceiver(JNIEnv* env,
77        jobject receiverObj, const sp<InputChannel>& inputChannel,
78        const sp<MessageQueue>& messageQueue) :
79        mReceiverObjGlobal(env->NewGlobalRef(receiverObj)),
80        mInputConsumer(inputChannel), mMessageQueue(messageQueue),
81        mBatchedInputEventPending(false) {
82#if DEBUG_DISPATCH_CYCLE
83    ALOGD("channel '%s' ~ Initializing input event receiver.", getInputChannelName());
84#endif
85}
86
87NativeInputEventReceiver::~NativeInputEventReceiver() {
88    JNIEnv* env = AndroidRuntime::getJNIEnv();
89    env->DeleteGlobalRef(mReceiverObjGlobal);
90}
91
92status_t NativeInputEventReceiver::initialize() {
93    int receiveFd = mInputConsumer.getChannel()->getFd();
94    mMessageQueue->getLooper()->addFd(receiveFd, 0, ALOOPER_EVENT_INPUT, this, NULL);
95    return OK;
96}
97
98void NativeInputEventReceiver::dispose() {
99#if DEBUG_DISPATCH_CYCLE
100    ALOGD("channel '%s' ~ Disposing input event receiver.", getInputChannelName());
101#endif
102
103    mMessageQueue->getLooper()->removeFd(mInputConsumer.getChannel()->getFd());
104}
105
106status_t NativeInputEventReceiver::finishInputEvent(uint32_t seq, bool handled) {
107#if DEBUG_DISPATCH_CYCLE
108    ALOGD("channel '%s' ~ Finished input event.", getInputChannelName());
109#endif
110
111    status_t status = mInputConsumer.sendFinishedSignal(seq, handled);
112    if (status) {
113        ALOGW("Failed to send finished signal on channel '%s'.  status=%d",
114                getInputChannelName(), status);
115    }
116    return status;
117}
118
119int NativeInputEventReceiver::handleEvent(int receiveFd, int events, void* data) {
120    if (events & (ALOOPER_EVENT_ERROR | ALOOPER_EVENT_HANGUP)) {
121        ALOGE("channel '%s' ~ Publisher closed input channel or an error occurred.  "
122                "events=0x%x", getInputChannelName(), events);
123        return 0; // remove the callback
124    }
125
126    if (!(events & ALOOPER_EVENT_INPUT)) {
127        ALOGW("channel '%s' ~ Received spurious callback for unhandled poll event.  "
128                "events=0x%x", getInputChannelName(), events);
129        return 1;
130    }
131
132    JNIEnv* env = AndroidRuntime::getJNIEnv();
133    status_t status = consumeEvents(env, false /*consumeBatches*/, -1);
134    mMessageQueue->raiseAndClearException(env, "handleReceiveCallback");
135    return status == OK || status == NO_MEMORY ? 1 : 0;
136}
137
138status_t NativeInputEventReceiver::consumeEvents(JNIEnv* env,
139        bool consumeBatches, nsecs_t frameTime) {
140#if DEBUG_DISPATCH_CYCLE
141    ALOGD("channel '%s' ~ Consuming input events, consumeBatches=%s, frameTime=%lld.",
142            getInputChannelName(), consumeBatches ? "true" : "false", frameTime);
143#endif
144
145    if (consumeBatches) {
146        mBatchedInputEventPending = false;
147    }
148
149    bool skipCallbacks = false;
150    for (;;) {
151        uint32_t seq;
152        InputEvent* inputEvent;
153        status_t status = mInputConsumer.consume(&mInputEventFactory,
154                consumeBatches, frameTime, &seq, &inputEvent);
155        if (status) {
156            if (status == WOULD_BLOCK) {
157                if (!skipCallbacks && !mBatchedInputEventPending
158                        && mInputConsumer.hasPendingBatch()) {
159                    // There is a pending batch.  Come back later.
160                    mBatchedInputEventPending = true;
161#if DEBUG_DISPATCH_CYCLE
162                    ALOGD("channel '%s' ~ Dispatching batched input event pending notification.",
163                            getInputChannelName());
164#endif
165                    env->CallVoidMethod(mReceiverObjGlobal,
166                            gInputEventReceiverClassInfo.dispatchBatchedInputEventPending);
167                    if (env->ExceptionCheck()) {
168                        ALOGE("Exception dispatching batched input events.");
169                        mBatchedInputEventPending = false; // try again later
170                    }
171                }
172                return OK;
173            }
174            ALOGE("channel '%s' ~ Failed to consume input event.  status=%d",
175                    getInputChannelName(), status);
176            return status;
177        }
178        assert(inputEvent);
179
180        if (!skipCallbacks) {
181            jobject inputEventObj;
182            switch (inputEvent->getType()) {
183            case AINPUT_EVENT_TYPE_KEY:
184#if DEBUG_DISPATCH_CYCLE
185                ALOGD("channel '%s' ~ Received key event.", getInputChannelName());
186#endif
187                inputEventObj = android_view_KeyEvent_fromNative(env,
188                        static_cast<KeyEvent*>(inputEvent));
189                break;
190
191            case AINPUT_EVENT_TYPE_MOTION:
192#if DEBUG_DISPATCH_CYCLE
193                ALOGD("channel '%s' ~ Received motion event.", getInputChannelName());
194#endif
195                inputEventObj = android_view_MotionEvent_obtainAsCopy(env,
196                        static_cast<MotionEvent*>(inputEvent));
197                break;
198
199            default:
200                assert(false); // InputConsumer should prevent this from ever happening
201                inputEventObj = NULL;
202            }
203
204            if (inputEventObj) {
205#if DEBUG_DISPATCH_CYCLE
206                ALOGD("channel '%s' ~ Dispatching input event.", getInputChannelName());
207#endif
208                env->CallVoidMethod(mReceiverObjGlobal,
209                        gInputEventReceiverClassInfo.dispatchInputEvent, seq, inputEventObj);
210                if (env->ExceptionCheck()) {
211                    ALOGE("Exception dispatching input event.");
212                    skipCallbacks = true;
213                }
214            } else {
215                ALOGW("channel '%s' ~ Failed to obtain event object.", getInputChannelName());
216                skipCallbacks = true;
217            }
218        }
219
220        if (skipCallbacks) {
221            mInputConsumer.sendFinishedSignal(seq, false);
222        }
223    }
224}
225
226
227static jint nativeInit(JNIEnv* env, jclass clazz, jobject receiverObj,
228        jobject inputChannelObj, jobject messageQueueObj) {
229    sp<InputChannel> inputChannel = android_view_InputChannel_getInputChannel(env,
230            inputChannelObj);
231    if (inputChannel == NULL) {
232        jniThrowRuntimeException(env, "InputChannel is not initialized.");
233        return 0;
234    }
235
236    sp<MessageQueue> messageQueue = android_os_MessageQueue_getMessageQueue(env, messageQueueObj);
237    if (messageQueue == NULL) {
238        jniThrowRuntimeException(env, "MessageQueue is not initialized.");
239        return 0;
240    }
241
242    sp<NativeInputEventReceiver> receiver = new NativeInputEventReceiver(env,
243            receiverObj, inputChannel, messageQueue);
244    status_t status = receiver->initialize();
245    if (status) {
246        String8 message;
247        message.appendFormat("Failed to initialize input event receiver.  status=%d", status);
248        jniThrowRuntimeException(env, message.string());
249        return 0;
250    }
251
252    receiver->incStrong(gInputEventReceiverClassInfo.clazz); // retain a reference for the object
253    return reinterpret_cast<jint>(receiver.get());
254}
255
256static void nativeDispose(JNIEnv* env, jclass clazz, jint receiverPtr) {
257    sp<NativeInputEventReceiver> receiver =
258            reinterpret_cast<NativeInputEventReceiver*>(receiverPtr);
259    receiver->dispose();
260    receiver->decStrong(gInputEventReceiverClassInfo.clazz); // drop reference held by the object
261}
262
263static void nativeFinishInputEvent(JNIEnv* env, jclass clazz, jint receiverPtr,
264        jint seq, jboolean handled) {
265    sp<NativeInputEventReceiver> receiver =
266            reinterpret_cast<NativeInputEventReceiver*>(receiverPtr);
267    status_t status = receiver->finishInputEvent(seq, handled);
268    if (status && status != DEAD_OBJECT) {
269        String8 message;
270        message.appendFormat("Failed to finish input event.  status=%d", status);
271        jniThrowRuntimeException(env, message.string());
272    }
273}
274
275static void nativeConsumeBatchedInputEvents(JNIEnv* env, jclass clazz, jint receiverPtr,
276        jlong frameTimeNanos) {
277    sp<NativeInputEventReceiver> receiver =
278            reinterpret_cast<NativeInputEventReceiver*>(receiverPtr);
279    status_t status = receiver->consumeEvents(env, true /*consumeBatches*/, frameTimeNanos);
280    if (status && status != DEAD_OBJECT && !env->ExceptionCheck()) {
281        String8 message;
282        message.appendFormat("Failed to consume batched input event.  status=%d", status);
283        jniThrowRuntimeException(env, message.string());
284    }
285}
286
287
288static JNINativeMethod gMethods[] = {
289    /* name, signature, funcPtr */
290    { "nativeInit",
291            "(Landroid/view/InputEventReceiver;Landroid/view/InputChannel;Landroid/os/MessageQueue;)I",
292            (void*)nativeInit },
293    { "nativeDispose", "(I)V",
294            (void*)nativeDispose },
295    { "nativeFinishInputEvent", "(IIZ)V",
296            (void*)nativeFinishInputEvent },
297    { "nativeConsumeBatchedInputEvents", "(IJ)V",
298            (void*)nativeConsumeBatchedInputEvents },
299};
300
301#define FIND_CLASS(var, className) \
302        var = env->FindClass(className); \
303        LOG_FATAL_IF(! var, "Unable to find class " className); \
304        var = jclass(env->NewGlobalRef(var));
305
306#define GET_METHOD_ID(var, clazz, methodName, methodDescriptor) \
307        var = env->GetMethodID(clazz, methodName, methodDescriptor); \
308        LOG_FATAL_IF(! var, "Unable to find method " methodName);
309
310int register_android_view_InputEventReceiver(JNIEnv* env) {
311    int res = jniRegisterNativeMethods(env, "android/view/InputEventReceiver",
312            gMethods, NELEM(gMethods));
313    LOG_FATAL_IF(res < 0, "Unable to register native methods.");
314
315    FIND_CLASS(gInputEventReceiverClassInfo.clazz, "android/view/InputEventReceiver");
316
317    GET_METHOD_ID(gInputEventReceiverClassInfo.dispatchInputEvent,
318            gInputEventReceiverClassInfo.clazz,
319            "dispatchInputEvent", "(ILandroid/view/InputEvent;)V");
320    GET_METHOD_ID(gInputEventReceiverClassInfo.dispatchBatchedInputEventPending,
321            gInputEventReceiverClassInfo.clazz,
322            "dispatchBatchedInputEventPending", "()V");
323    return 0;
324}
325
326} // namespace android
327