int NativeInputEventReceiver::handleEvent(int receiveFd, int events, void* data)

gistfile1.cpp

int NativeInputEventReceiver::handleEvent(int receiveFd, int events, void* data) {
....

    if (events & ALOOPER_EVENT_INPUT) {
        JNIEnv* env = AndroidRuntime::getJNIEnv();
        status_t status = consumeEvents(env, false /*consumeBatches*/, -1, NULL);
        mMessageQueue->raiseAndClearException(env, "handleReceiveCallback");
        return status == OK || status == NO_MEMORY ? 1 : 0;
    }

    if (events & ALOOPER_EVENT_OUTPUT) {
        for (size_t i = 0; i < mFinishQueue.size(); i++) {
            const Finish& finish = mFinishQueue.itemAt(i);
            status_t status = mInputConsumer.sendFinishedSignal(finish.seq, finish.handled);
            ...
        }

        mFinishQueue.clear();
        setFdEvents(ALOOPER_EVENT_INPUT);
        return 1;
    }
}

status_t NativeInputEventReceiver::consumeEvents(JNIEnv* env,
        bool consumeBatches, nsecs_t frameTime, bool* outConsumedBatch) {
#if DEBUG_DISPATCH_CYCLE
    ALOGD("channel '%s' ~ Consuming input events, consumeBatches=%s, frameTime=%lld.",
            getInputChannelName(), consumeBatches ? "true" : "false", frameTime);
#endif

    if (consumeBatches) {
        mBatchedInputEventPending = false;
    }
    if (outConsumedBatch) {
        *outConsumedBatch = false;
    }

    ScopedLocalRef<jobject> receiverObj(env, NULL);
    bool skipCallbacks = false;
    for (;;) {
        uint32_t seq;
        InputEvent* inputEvent;
        status_t status = mInputConsumer.consume(&mInputEventFactory,
                consumeBatches, frameTime, &seq, &inputEvent);
        if (status) {
            if (status == WOULD_BLOCK) {
                if (!skipCallbacks && !mBatchedInputEventPending
                        && mInputConsumer.hasPendingBatch()) {
                    // There is a pending batch.  Come back later.
                    if (!receiverObj.get()) {
                        receiverObj.reset(jniGetReferent(env, mReceiverWeakGlobal));
                        if (!receiverObj.get()) {
                            ALOGW("channel '%s' ~ Receiver object was finalized "
                                    "without being disposed.", getInputChannelName());
                            return DEAD_OBJECT;
                        }
                    }

                    mBatchedInputEventPending = true;
#if DEBUG_DISPATCH_CYCLE
                    ALOGD("channel '%s' ~ Dispatching batched input event pending notification.",
                            getInputChannelName());
#endif
                    env->CallVoidMethod(receiverObj.get(),
                            gInputEventReceiverClassInfo.dispatchBatchedInputEventPending);
                    if (env->ExceptionCheck()) {
                        ALOGE("Exception dispatching batched input events.");
                        mBatchedInputEventPending = false; // try again later
                    }
                }
                return OK;
            }
            ALOGE("channel '%s' ~ Failed to consume input event.  status=%d",
                    getInputChannelName(), status);
            return status;
        }
        assert(inputEvent);

        if (!skipCallbacks) {
            if (!receiverObj.get()) {
                receiverObj.reset(jniGetReferent(env, mReceiverWeakGlobal));
                if (!receiverObj.get()) {
                    ALOGW("channel '%s' ~ Receiver object was finalized "
                            "without being disposed.", getInputChannelName());
                    return DEAD_OBJECT;
                }
            }

            jobject inputEventObj;
            switch (inputEvent->getType()) {
            case AINPUT_EVENT_TYPE_KEY:
#if DEBUG_DISPATCH_CYCLE
                ALOGD("channel '%s' ~ Received key event.", getInputChannelName());
#endif
                inputEventObj = android_view_KeyEvent_fromNative(env,
                        static_cast<KeyEvent*>(inputEvent));
                break;

            case AINPUT_EVENT_TYPE_MOTION: {
#if DEBUG_DISPATCH_CYCLE
                ALOGD("channel '%s' ~ Received motion event.", getInputChannelName());
#endif
                MotionEvent* motionEvent = static_cast<MotionEvent*>(inputEvent);
                if ((motionEvent->getAction() & AMOTION_EVENT_ACTION_MOVE) && outConsumedBatch) {
                    *outConsumedBatch = true;
                }
                inputEventObj = android_view_MotionEvent_obtainAsCopy(env, motionEvent);
                break;
            }

            default:
                assert(false); // InputConsumer should prevent this from ever happening
                inputEventObj = NULL;
            }

            if (inputEventObj) {
#if DEBUG_DISPATCH_CYCLE
                ALOGD("channel '%s' ~ Dispatching input event.", getInputChannelName());
#endif
                env->CallVoidMethod(receiverObj.get(),
                        gInputEventReceiverClassInfo.dispatchInputEvent, seq, inputEventObj);
                if (env->ExceptionCheck()) {
                    ALOGE("Exception dispatching input event.");
                    skipCallbacks = true;
                }
                env->DeleteLocalRef(inputEventObj);
            } else {
                ALOGW("channel '%s' ~ Failed to obtain event object.", getInputChannelName());
                skipCallbacks = true;
            }
        }

        if (skipCallbacks) {
            mInputConsumer.sendFinishedSignal(seq, false);
        }
    }
}