Rewrite input handling for native applications
Bug: 8473020
Change-Id: Ic4353d8924ab877bec21aff8c2dba9fe725bf906
diff --git a/core/jni/android_view_InputQueue.cpp b/core/jni/android_view_InputQueue.cpp
new file mode 100644
index 0000000..ec56afa
--- /dev/null
+++ b/core/jni/android_view_InputQueue.cpp
@@ -0,0 +1,282 @@
+/*
+ * Copyright (C) 2013 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.
+ */
+
+#define LOG_TAG "InputQueue"
+
+#include <fcntl.h>
+#include <string.h>
+#include <unistd.h>
+
+#include <android/input.h>
+#include <android_runtime/AndroidRuntime.h>
+#include <android_runtime/android_view_InputQueue.h>
+#include <androidfw/Input.h>
+#include <utils/Looper.h>
+#include <utils/TypeHelpers.h>
+#include <ScopedLocalRef.h>
+
+#include "JNIHelp.h"
+#include "android_os_MessageQueue.h"
+#include "android_view_KeyEvent.h"
+#include "android_view_MotionEvent.h"
+
+namespace android {
+
+static struct {
+ jmethodID finishInputEvent;
+} gInputQueueClassInfo;
+
+enum {
+ MSG_FINISH_INPUT = 1,
+};
+
+InputQueue::InputQueue(jobject inputQueueObj, const sp<Looper>& looper,
+ int dispatchReadFd, int dispatchWriteFd) :
+ mDispatchReadFd(dispatchReadFd), mDispatchWriteFd(dispatchWriteFd),
+ mDispatchLooper(looper), mHandler(new WeakMessageHandler(this)) {
+ JNIEnv* env = AndroidRuntime::getJNIEnv();
+ mInputQueueWeakGlobal = env->NewGlobalRef(inputQueueObj);
+}
+
+InputQueue::~InputQueue() {
+ mDispatchLooper->removeMessages(mHandler);
+ JNIEnv* env = AndroidRuntime::getJNIEnv();
+ env->DeleteGlobalRef(mInputQueueWeakGlobal);
+ close(mDispatchReadFd);
+ close(mDispatchWriteFd);
+}
+
+void InputQueue::attachLooper(Looper* looper, int ident,
+ ALooper_callbackFunc callback, void* data) {
+ Mutex::Autolock _l(mLock);
+ for (size_t i = 0; i < mAppLoopers.size(); i++) {
+ if (looper == mAppLoopers[i]) {
+ return;
+ }
+ }
+ mAppLoopers.push(looper);
+ looper->addFd(mDispatchReadFd, ident, ALOOPER_EVENT_INPUT, callback, data);
+}
+
+void InputQueue::detachLooper() {
+ Mutex::Autolock _l(mLock);
+ detachLooperLocked();
+}
+
+void InputQueue::detachLooperLocked() {
+ for (size_t i = 0; i < mAppLoopers.size(); i++) {
+ mAppLoopers[i]->removeFd(mDispatchReadFd);
+ }
+ mAppLoopers.clear();
+}
+
+bool InputQueue::hasEvents() {
+ Mutex::Autolock _l(mLock);
+ return mPendingEvents.size() > 0;
+}
+
+status_t InputQueue::getEvent(InputEvent** outEvent) {
+ Mutex::Autolock _l(mLock);
+ *outEvent = NULL;
+ if (!mPendingEvents.isEmpty()) {
+ *outEvent = mPendingEvents[0];
+ mPendingEvents.removeAt(0);
+ }
+
+ if (mPendingEvents.isEmpty()) {
+ char byteread[16];
+ ssize_t nRead;
+ do {
+ nRead = TEMP_FAILURE_RETRY(read(mDispatchReadFd, &byteread, sizeof(byteread)));
+ if (nRead < 0 && errno != EAGAIN) {
+ ALOGW("Failed to read from native dispatch pipe: %s", strerror(errno));
+ }
+ } while (nRead > 0);
+ }
+
+ return *outEvent != NULL ? OK : WOULD_BLOCK;
+}
+
+bool InputQueue::preDispatchEvent(InputEvent* e) {
+ if (e->getType() == AINPUT_EVENT_TYPE_KEY) {
+ KeyEvent* keyEvent = static_cast<KeyEvent*>(e);
+ if (keyEvent->getFlags() & AKEY_EVENT_FLAG_PREDISPATCH) {
+ finishEvent(e, false);
+ return true;
+ }
+ }
+ return false;
+}
+
+void InputQueue::finishEvent(InputEvent* event, bool handled) {
+ Mutex::Autolock _l(mLock);
+ mFinishedEvents.push(key_value_pair_t<InputEvent*, bool>(event, handled));
+ if (mFinishedEvents.size() == 1) {
+ mDispatchLooper->sendMessage(this, Message(MSG_FINISH_INPUT));
+ }
+}
+
+void InputQueue::handleMessage(const Message& message) {
+ switch(message.what) {
+ case MSG_FINISH_INPUT:
+ JNIEnv* env = AndroidRuntime::getJNIEnv();
+ ScopedLocalRef<jobject> inputQueueObj(env, jniGetReferent(env, mInputQueueWeakGlobal));
+ if (!inputQueueObj.get()) {
+ ALOGW("InputQueue was finalized without being disposed");
+ return;
+ }
+ while (true) {
+ InputEvent* event;
+ bool handled;
+ {
+ Mutex::Autolock _l(mLock);
+ if (mFinishedEvents.isEmpty()) {
+ break;
+ }
+ event = mFinishedEvents[0].getKey();
+ handled = mFinishedEvents[0].getValue();
+ mFinishedEvents.removeAt(0);
+ }
+ env->CallVoidMethod(inputQueueObj.get(), gInputQueueClassInfo.finishInputEvent,
+ reinterpret_cast<jint>(event), handled);
+ recycleInputEvent(event);
+ }
+ break;
+ }
+}
+
+void InputQueue::recycleInputEvent(InputEvent* event) {
+ mPooledInputEventFactory.recycle(event);
+}
+
+KeyEvent* InputQueue::createKeyEvent() {
+ return mPooledInputEventFactory.createKeyEvent();
+}
+
+MotionEvent* InputQueue::createMotionEvent() {
+ return mPooledInputEventFactory.createMotionEvent();
+}
+
+void InputQueue::enqueueEvent(InputEvent* event) {
+ Mutex::Autolock _l(mLock);
+ mPendingEvents.push(event);
+ if (mPendingEvents.size() == 1) {
+ char dummy = 0;
+ int res = TEMP_FAILURE_RETRY(write(mDispatchWriteFd, &dummy, sizeof(dummy)));
+ if (res < 0 && errno != EAGAIN) {
+ ALOGW("Failed writing to dispatch fd: %s", strerror(errno));
+ }
+ }
+}
+
+InputQueue* InputQueue::createQueue(jobject inputQueueObj, const sp<Looper>& looper) {
+ int pipeFds[2];
+ if (pipe(pipeFds)) {
+ ALOGW("Could not create native input dispatching pipe: %s", strerror(errno));
+ return NULL;
+ }
+ fcntl(pipeFds[0], F_SETFL, O_NONBLOCK);
+ fcntl(pipeFds[1], F_SETFL, O_NONBLOCK);
+ return new InputQueue(inputQueueObj, looper, pipeFds[0], pipeFds[1]);
+}
+
+static jint nativeInit(JNIEnv* env, jobject clazz, jobject queueWeak, jobject jMsgQueue) {
+ sp<MessageQueue> messageQueue = android_os_MessageQueue_getMessageQueue(env, jMsgQueue);
+ if (messageQueue == NULL) {
+ jniThrowRuntimeException(env, "MessageQueue is not initialized.");
+ return 0;
+ }
+ sp<InputQueue> queue = InputQueue::createQueue(queueWeak, messageQueue->getLooper());
+ if (!queue.get()) {
+ jniThrowRuntimeException(env, "InputQueue failed to initialize");
+ return 0;
+ }
+ queue->incStrong(&gInputQueueClassInfo);
+ return reinterpret_cast<jint>(queue.get());
+}
+
+static void nativeDispose(JNIEnv* env, jobject clazz, jint ptr) {
+ sp<InputQueue> queue = reinterpret_cast<InputQueue*>(ptr);
+ queue->detachLooper();
+ queue->decStrong(&gInputQueueClassInfo);
+}
+
+static jint nativeSendKeyEvent(JNIEnv* env, jobject clazz, jint ptr, jobject eventObj,
+ jboolean predispatch) {
+ InputQueue* queue = reinterpret_cast<InputQueue*>(ptr);
+ KeyEvent* event = queue->createKeyEvent();
+ status_t status = android_view_KeyEvent_toNative(env, eventObj, event);
+ if (status) {
+ queue->recycleInputEvent(event);
+ jniThrowRuntimeException(env, "Could not read contents of KeyEvent object.");
+ return -1;
+ }
+
+ if (predispatch) {
+ event->setFlags(event->getFlags() | AKEY_EVENT_FLAG_PREDISPATCH);
+ }
+
+ queue->enqueueEvent(event);
+ return reinterpret_cast<jint>(event);
+}
+
+static jint nativeSendMotionEvent(JNIEnv* env, jobject clazz, jint ptr, jobject eventObj) {
+ sp<InputQueue> queue = reinterpret_cast<InputQueue*>(ptr);
+ MotionEvent* originalEvent = android_view_MotionEvent_getNativePtr(env, eventObj);
+ if (!originalEvent) {
+ jniThrowRuntimeException(env, "Could not obtain MotionEvent pointer.");
+ return -1;
+ }
+ MotionEvent* event = queue->createMotionEvent();
+ event->copyFrom(originalEvent, true /* keepHistory */);
+ queue->enqueueEvent(event);
+ return reinterpret_cast<jint>(event);
+}
+
+static const JNINativeMethod g_methods[] = {
+ { "nativeInit", "(Ljava/lang/ref/WeakReference;Landroid/os/MessageQueue;)I",
+ (void*) nativeInit },
+ { "nativeDispose", "(I)V", (void*) nativeDispose },
+ { "nativeSendKeyEvent", "(ILandroid/view/KeyEvent;Z)I", (void*) nativeSendKeyEvent },
+ { "nativeSendMotionEvent", "(ILandroid/view/MotionEvent;)I", (void*) nativeSendMotionEvent },
+};
+
+static const char* const kInputQueuePathName = "android/view/InputQueue";
+
+#define FIND_CLASS(var, className) \
+ do { \
+ var = env->FindClass(className); \
+ LOG_FATAL_IF(! var, "Unable to find class %s", className); \
+ } while(0)
+
+#define GET_METHOD_ID(var, clazz, methodName, fieldDescriptor) \
+ do { \
+ var = env->GetMethodID(clazz, methodName, fieldDescriptor); \
+ LOG_FATAL_IF(! var, "Unable to find method" methodName); \
+ } while(0)
+
+int register_android_view_InputQueue(JNIEnv* env)
+{
+ jclass clazz;
+ FIND_CLASS(clazz, kInputQueuePathName);
+ GET_METHOD_ID(gInputQueueClassInfo.finishInputEvent, clazz, "finishInputEvent", "(IZ)V");
+
+ return AndroidRuntime::registerNativeMethods(
+ env, kInputQueuePathName,
+ g_methods, NELEM(g_methods));
+}
+
+} // namespace android