Prevent events from getting backlogged.

This change implements two heuristics.

1. When events are older than 10 seconds, they are dropped.

2. If the application is currently busy processing an event and
   the user touches a window belonging to a different application
   then we drop the currently queued events so the other application
   can start processing the gesture immediately.

Note that the system takes care of synthesizing cancelation events
automatically for any events that it drops.

Added some new handle types to allow the native dispatcher to
indirectly refer to the WindowManager's window state and app window
token.  This was done to enable the dispatcher to identify the
application to which each window belongs but it also eliminates
some lookup tables and linear searches through the window list
on each key press.

Bug: 3224911
Change-Id: I9dae8dfe23d195d76865f97011fe2f1d351e2940

1 files changed, 240 insertions, 0 deletions

diff --git a/services/jni/com_android_server_InputWindow.cpp b/services/jni/com_android_server_InputWindow.cpp
new file mode 100644
index 0000000..a4609a0
--- /dev/null
+++ b/services/jni/com_android_server_InputWindow.cpp
@@ -0,0 +1,240 @@
+/*
+ * Copyright (C) 2011 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 "InputWindow"
+
+#include "JNIHelp.h"
+#include "jni.h"
+#include <android_runtime/AndroidRuntime.h>
+
+#include <android_view_InputChannel.h>
+#include "com_android_server_InputWindow.h"
+#include "com_android_server_InputWindowHandle.h"
+
+namespace android {
+
+static struct {
+    jclass clazz;
+
+    jfieldID inputWindowHandle;
+    jfieldID inputChannel;
+    jfieldID name;
+    jfieldID layoutParamsFlags;
+    jfieldID layoutParamsType;
+    jfieldID dispatchingTimeoutNanos;
+    jfieldID frameLeft;
+    jfieldID frameTop;
+    jfieldID frameRight;
+    jfieldID frameBottom;
+    jfieldID visibleFrameLeft;
+    jfieldID visibleFrameTop;
+    jfieldID visibleFrameRight;
+    jfieldID visibleFrameBottom;
+    jfieldID touchableAreaLeft;
+    jfieldID touchableAreaTop;
+    jfieldID touchableAreaRight;
+    jfieldID touchableAreaBottom;
+    jfieldID visible;
+    jfieldID canReceiveKeys;
+    jfieldID hasFocus;
+    jfieldID hasWallpaper;
+    jfieldID paused;
+    jfieldID layer;
+    jfieldID ownerPid;
+    jfieldID ownerUid;
+} gInputWindowClassInfo;
+
+
+// --- Global functions ---
+
+void android_server_InputWindow_toNative(
+        JNIEnv* env, jobject inputWindowObj, InputWindow* outInputWindow) {
+    jobject inputWindowHandleObj = env->GetObjectField(inputWindowObj,
+            gInputWindowClassInfo.inputWindowHandle);
+    if (inputWindowHandleObj) {
+        outInputWindow->inputWindowHandle =
+                android_server_InputWindowHandle_getHandle(env, inputWindowHandleObj);
+        env->DeleteLocalRef(inputWindowHandleObj);
+    } else {
+        outInputWindow->inputWindowHandle = NULL;
+    }
+
+    jobject inputChannelObj = env->GetObjectField(inputWindowObj,
+            gInputWindowClassInfo.inputChannel);
+    if (inputChannelObj) {
+        outInputWindow->inputChannel =
+                android_view_InputChannel_getInputChannel(env, inputChannelObj);
+        env->DeleteLocalRef(inputChannelObj);
+    } else {
+        outInputWindow->inputChannel = NULL;
+    }
+
+    jstring nameObj = jstring(env->GetObjectField(inputWindowObj,
+            gInputWindowClassInfo.name));
+    if (nameObj) {
+        const char* nameStr = env->GetStringUTFChars(nameObj, NULL);
+        outInputWindow->name.setTo(nameStr);
+        env->ReleaseStringUTFChars(nameObj, nameStr);
+        env->DeleteLocalRef(nameObj);
+    } else {
+        LOGE("InputWindow.name should not be null.");
+        outInputWindow->name.setTo("unknown");
+    }
+
+    outInputWindow->layoutParamsFlags = env->GetIntField(inputWindowObj,
+            gInputWindowClassInfo.layoutParamsFlags);
+    outInputWindow->layoutParamsType = env->GetIntField(inputWindowObj,
+            gInputWindowClassInfo.layoutParamsType);
+    outInputWindow->dispatchingTimeout = env->GetLongField(inputWindowObj,
+            gInputWindowClassInfo.dispatchingTimeoutNanos);
+    outInputWindow->frameLeft = env->GetIntField(inputWindowObj,
+            gInputWindowClassInfo.frameLeft);
+    outInputWindow->frameTop = env->GetIntField(inputWindowObj,
+            gInputWindowClassInfo.frameTop);
+    outInputWindow->frameRight = env->GetIntField(inputWindowObj,
+            gInputWindowClassInfo.frameRight);
+    outInputWindow->frameBottom = env->GetIntField(inputWindowObj,
+            gInputWindowClassInfo.frameBottom);
+    outInputWindow->visibleFrameLeft = env->GetIntField(inputWindowObj,
+            gInputWindowClassInfo.visibleFrameLeft);
+    outInputWindow->visibleFrameTop = env->GetIntField(inputWindowObj,
+            gInputWindowClassInfo.visibleFrameTop);
+    outInputWindow->visibleFrameRight = env->GetIntField(inputWindowObj,
+            gInputWindowClassInfo.visibleFrameRight);
+    outInputWindow->visibleFrameBottom = env->GetIntField(inputWindowObj,
+            gInputWindowClassInfo.visibleFrameBottom);
+    outInputWindow->touchableAreaLeft = env->GetIntField(inputWindowObj,
+            gInputWindowClassInfo.touchableAreaLeft);
+    outInputWindow->touchableAreaTop = env->GetIntField(inputWindowObj,
+            gInputWindowClassInfo.touchableAreaTop);
+    outInputWindow->touchableAreaRight = env->GetIntField(inputWindowObj,
+            gInputWindowClassInfo.touchableAreaRight);
+    outInputWindow->touchableAreaBottom = env->GetIntField(inputWindowObj,
+            gInputWindowClassInfo.touchableAreaBottom);
+    outInputWindow->visible = env->GetBooleanField(inputWindowObj,
+            gInputWindowClassInfo.visible);
+    outInputWindow->canReceiveKeys = env->GetBooleanField(inputWindowObj,
+            gInputWindowClassInfo.canReceiveKeys);
+    outInputWindow->hasFocus = env->GetBooleanField(inputWindowObj,
+            gInputWindowClassInfo.hasFocus);
+    outInputWindow->hasWallpaper = env->GetBooleanField(inputWindowObj,
+            gInputWindowClassInfo.hasWallpaper);
+    outInputWindow->paused = env->GetBooleanField(inputWindowObj,
+            gInputWindowClassInfo.paused);
+    outInputWindow->layer = env->GetIntField(inputWindowObj,
+            gInputWindowClassInfo.layer);
+    outInputWindow->ownerPid = env->GetIntField(inputWindowObj,
+            gInputWindowClassInfo.ownerPid);
+    outInputWindow->ownerUid = env->GetIntField(inputWindowObj,
+            gInputWindowClassInfo.ownerUid);
+}
+
+
+// --- JNI ---
+
+#define FIND_CLASS(var, className) \
+        var = env->FindClass(className); \
+        LOG_FATAL_IF(! var, "Unable to find class " className); \
+        var = jclass(env->NewGlobalRef(var));
+
+#define GET_FIELD_ID(var, clazz, fieldName, fieldDescriptor) \
+        var = env->GetFieldID(clazz, fieldName, fieldDescriptor); \
+        LOG_FATAL_IF(! var, "Unable to find field " fieldName);
+
+int register_android_server_InputWindow(JNIEnv* env) {
+    FIND_CLASS(gInputWindowClassInfo.clazz, "com/android/server/InputWindow");
+
+    GET_FIELD_ID(gInputWindowClassInfo.inputWindowHandle, gInputWindowClassInfo.clazz,
+            "inputWindowHandle", "Lcom/android/server/InputWindowHandle;");
+
+    GET_FIELD_ID(gInputWindowClassInfo.inputChannel, gInputWindowClassInfo.clazz,
+            "inputChannel", "Landroid/view/InputChannel;");
+
+    GET_FIELD_ID(gInputWindowClassInfo.name, gInputWindowClassInfo.clazz,
+            "name", "Ljava/lang/String;");
+
+    GET_FIELD_ID(gInputWindowClassInfo.layoutParamsFlags, gInputWindowClassInfo.clazz,
+            "layoutParamsFlags", "I");
+
+    GET_FIELD_ID(gInputWindowClassInfo.layoutParamsType, gInputWindowClassInfo.clazz,
+            "layoutParamsType", "I");
+
+    GET_FIELD_ID(gInputWindowClassInfo.dispatchingTimeoutNanos, gInputWindowClassInfo.clazz,
+            "dispatchingTimeoutNanos", "J");
+
+    GET_FIELD_ID(gInputWindowClassInfo.frameLeft, gInputWindowClassInfo.clazz,
+            "frameLeft", "I");
+
+    GET_FIELD_ID(gInputWindowClassInfo.frameTop, gInputWindowClassInfo.clazz,
+            "frameTop", "I");
+
+    GET_FIELD_ID(gInputWindowClassInfo.frameRight, gInputWindowClassInfo.clazz,
+            "frameRight", "I");
+
+    GET_FIELD_ID(gInputWindowClassInfo.frameBottom, gInputWindowClassInfo.clazz,
+            "frameBottom", "I");
+
+    GET_FIELD_ID(gInputWindowClassInfo.visibleFrameLeft, gInputWindowClassInfo.clazz,
+            "visibleFrameLeft", "I");
+
+    GET_FIELD_ID(gInputWindowClassInfo.visibleFrameTop, gInputWindowClassInfo.clazz,
+            "visibleFrameTop", "I");
+
+    GET_FIELD_ID(gInputWindowClassInfo.visibleFrameRight, gInputWindowClassInfo.clazz,
+            "visibleFrameRight", "I");
+
+    GET_FIELD_ID(gInputWindowClassInfo.visibleFrameBottom, gInputWindowClassInfo.clazz,
+            "visibleFrameBottom", "I");
+
+    GET_FIELD_ID(gInputWindowClassInfo.touchableAreaLeft, gInputWindowClassInfo.clazz,
+            "touchableAreaLeft", "I");
+
+    GET_FIELD_ID(gInputWindowClassInfo.touchableAreaTop, gInputWindowClassInfo.clazz,
+            "touchableAreaTop", "I");
+
+    GET_FIELD_ID(gInputWindowClassInfo.touchableAreaRight, gInputWindowClassInfo.clazz,
+            "touchableAreaRight", "I");
+
+    GET_FIELD_ID(gInputWindowClassInfo.touchableAreaBottom, gInputWindowClassInfo.clazz,
+            "touchableAreaBottom", "I");
+
+    GET_FIELD_ID(gInputWindowClassInfo.visible, gInputWindowClassInfo.clazz,
+            "visible", "Z");
+
+    GET_FIELD_ID(gInputWindowClassInfo.canReceiveKeys, gInputWindowClassInfo.clazz,
+            "canReceiveKeys", "Z");
+
+    GET_FIELD_ID(gInputWindowClassInfo.hasFocus, gInputWindowClassInfo.clazz,
+            "hasFocus", "Z");
+
+    GET_FIELD_ID(gInputWindowClassInfo.hasWallpaper, gInputWindowClassInfo.clazz,
+            "hasWallpaper", "Z");
+
+    GET_FIELD_ID(gInputWindowClassInfo.paused, gInputWindowClassInfo.clazz,
+            "paused", "Z");
+
+    GET_FIELD_ID(gInputWindowClassInfo.layer, gInputWindowClassInfo.clazz,
+            "layer", "I");
+
+    GET_FIELD_ID(gInputWindowClassInfo.ownerPid, gInputWindowClassInfo.clazz,
+            "ownerPid", "I");
+
+    GET_FIELD_ID(gInputWindowClassInfo.ownerUid, gInputWindowClassInfo.clazz,
+            "ownerUid", "I");
+    return 0;
+}
+
+} /* namespace android */