1 files changed, 494 insertions, 0 deletions
diff --git a/services/core/java/com/android/server/dreams/DreamManagerService.java b/services/core/java/com/android/server/dreams/DreamManagerService.java
new file mode 100644
index 0000000..ffb113c
--- /dev/null
+++ b/services/core/java/com/android/server/dreams/DreamManagerService.java
@@ -0,0 +1,494 @@
+/*
+ * Copyright (C) 2012 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.
+ */
+
+package com.android.server.dreams;
+
+import com.android.internal.util.DumpUtils;
+import com.android.server.FgThread;
+import com.android.server.SystemService;
+
+import android.Manifest;
+import android.app.ActivityManager;
+import android.content.BroadcastReceiver;
+import android.content.ComponentName;
+import android.content.Context;
+import android.content.Intent;
+import android.content.IntentFilter;
+import android.content.pm.PackageManager;
+import android.content.pm.PackageManager.NameNotFoundException;
+import android.os.Binder;
+import android.os.Handler;
+import android.os.IBinder;
+import android.os.Looper;
+import android.os.PowerManager;
+import android.os.SystemClock;
+import android.os.UserHandle;
+import android.provider.Settings;
+import android.service.dreams.DreamManagerInternal;
+import android.service.dreams.DreamService;
+import android.service.dreams.IDreamManager;
+import android.util.Slog;
+
+import java.io.FileDescriptor;
+import java.io.PrintWriter;
+import java.util.ArrayList;
+import java.util.List;
+
+import libcore.util.Objects;
+
+/**
+ * Service api for managing dreams.
+ *
+ * @hide
+ */
+public final class DreamManagerService extends SystemService {
+    private static final boolean DEBUG = false;
+    private static final String TAG = "DreamManagerService";
+
+    private final Object mLock = new Object();
+
+    private final Context mContext;
+    private final DreamHandler mHandler;
+    private final DreamController mController;
+    private final PowerManager mPowerManager;
+
+    private Binder mCurrentDreamToken;
+    private ComponentName mCurrentDreamName;
+    private int mCurrentDreamUserId;
+    private boolean mCurrentDreamIsTest;
+
+    public DreamManagerService(Context context) {
+        super(context);
+        mContext = context;
+        mHandler = new DreamHandler(FgThread.get().getLooper());
+        mController = new DreamController(context, mHandler, mControllerListener);
+
+        mPowerManager = (PowerManager)context.getSystemService(Context.POWER_SERVICE);
+    }
+
+    @Override
+    public void onStart() {
+        publishBinderService(DreamService.DREAM_SERVICE, new BinderService());
+        publishLocalService(DreamManagerInternal.class, new LocalService());
+    }
+
+    @Override
+    public void onBootPhase(int phase) {
+        if (phase == SystemService.PHASE_THIRD_PARTY_APPS_CAN_START) {
+            mContext.registerReceiver(new BroadcastReceiver() {
+                @Override
+                public void onReceive(Context context, Intent intent) {
+                    synchronized (mLock) {
+                        stopDreamLocked();
+                    }
+                }
+            }, new IntentFilter(Intent.ACTION_USER_SWITCHED), null, mHandler);
+        }
+    }
+
+    private void dumpInternal(PrintWriter pw) {
+        pw.println("DREAM MANAGER (dumpsys dreams)");
+        pw.println();
+
+        pw.println("mCurrentDreamToken=" + mCurrentDreamToken);
+        pw.println("mCurrentDreamName=" + mCurrentDreamName);
+        pw.println("mCurrentDreamUserId=" + mCurrentDreamUserId);
+        pw.println("mCurrentDreamIsTest=" + mCurrentDreamIsTest);
+        pw.println();
+
+        DumpUtils.dumpAsync(mHandler, new DumpUtils.Dump() {
+            @Override
+            public void dump(PrintWriter pw) {
+                mController.dump(pw);
+            }
+        }, pw, 200);
+    }
+
+    private boolean isDreamingInternal() {
+        synchronized (mLock) {
+            return mCurrentDreamToken != null && !mCurrentDreamIsTest;
+        }
+    }
+
+    private void requestDreamInternal() {
+        // Ask the power manager to nap.  It will eventually call back into
+        // startDream() if/when it is appropriate to start dreaming.
+        // Because napping could cause the screen to turn off immediately if the dream
+        // cannot be started, we keep one eye open and gently poke user activity.
+        long time = SystemClock.uptimeMillis();
+        mPowerManager.userActivity(time, true /*noChangeLights*/);
+        mPowerManager.nap(time);
+    }
+
+    private void requestAwakenInternal() {
+        // Treat an explicit request to awaken as user activity so that the
+        // device doesn't immediately go to sleep if the timeout expired,
+        // for example when being undocked.
+        long time = SystemClock.uptimeMillis();
+        mPowerManager.userActivity(time, false /*noChangeLights*/);
+        stopDreamInternal();
+    }
+
+    private void finishSelfInternal(IBinder token) {
+        if (DEBUG) {
+            Slog.d(TAG, "Dream finished: " + token);
+        }
+
+        // Note that a dream finishing and self-terminating is not
+        // itself considered user activity.  If the dream is ending because
+        // the user interacted with the device then user activity will already
+        // have been poked so the device will stay awake a bit longer.
+        // If the dream is ending on its own for other reasons and no wake
+        // locks are held and the user activity timeout has expired then the
+        // device may simply go to sleep.
+        synchronized (mLock) {
+            if (mCurrentDreamToken == token) {
+                stopDreamLocked();
+            }
+        }
+    }
+
+    private void testDreamInternal(ComponentName dream, int userId) {
+        synchronized (mLock) {
+            startDreamLocked(dream, true /*isTest*/, userId);
+        }
+    }
+
+    private void startDreamInternal() {
+        int userId = ActivityManager.getCurrentUser();
+        ComponentName dream = chooseDreamForUser(userId);
+        if (dream != null) {
+            synchronized (mLock) {
+                startDreamLocked(dream, false /*isTest*/, userId);
+            }
+        }
+    }
+
+    private void stopDreamInternal() {
+        synchronized (mLock) {
+            stopDreamLocked();
+        }
+    }
+
+    private ComponentName chooseDreamForUser(int userId) {
+        ComponentName[] dreams = getDreamComponentsForUser(userId);
+        return dreams != null && dreams.length != 0 ? dreams[0] : null;
+    }
+
+    private ComponentName[] getDreamComponentsForUser(int userId) {
+        String names = Settings.Secure.getStringForUser(mContext.getContentResolver(),
+                Settings.Secure.SCREENSAVER_COMPONENTS,
+                userId);
+        ComponentName[] components = componentsFromString(names);
+
+        // first, ensure components point to valid services
+        List<ComponentName> validComponents = new ArrayList<ComponentName>();
+        if (components != null) {
+            for (ComponentName component : components) {
+                if (serviceExists(component)) {
+                    validComponents.add(component);
+                } else {
+                    Slog.w(TAG, "Dream " + component + " does not exist");
+                }
+            }
+        }
+
+        // fallback to the default dream component if necessary
+        if (validComponents.isEmpty()) {
+            ComponentName defaultDream = getDefaultDreamComponentForUser(userId);
+            if (defaultDream != null) {
+                Slog.w(TAG, "Falling back to default dream " + defaultDream);
+                validComponents.add(defaultDream);
+            }
+        }
+        return validComponents.toArray(new ComponentName[validComponents.size()]);
+    }
+
+    private void setDreamComponentsForUser(int userId, ComponentName[] componentNames) {
+        Settings.Secure.putStringForUser(mContext.getContentResolver(),
+                Settings.Secure.SCREENSAVER_COMPONENTS,
+                componentsToString(componentNames),
+                userId);
+    }
+
+    private ComponentName getDefaultDreamComponentForUser(int userId) {
+        String name = Settings.Secure.getStringForUser(mContext.getContentResolver(),
+                Settings.Secure.SCREENSAVER_DEFAULT_COMPONENT,
+                userId);
+        return name == null ? null : ComponentName.unflattenFromString(name);
+    }
+
+    private boolean serviceExists(ComponentName name) {
+        try {
+            return name != null && mContext.getPackageManager().getServiceInfo(name, 0) != null;
+        } catch (NameNotFoundException e) {
+            return false;
+        }
+    }
+
+    private void startDreamLocked(final ComponentName name,
+            final boolean isTest, final int userId) {
+        if (Objects.equal(mCurrentDreamName, name)
+                && mCurrentDreamIsTest == isTest
+                && mCurrentDreamUserId == userId) {
+            return;
+        }
+
+        stopDreamLocked();
+
+        if (DEBUG) Slog.i(TAG, "Entering dreamland.");
+
+        final Binder newToken = new Binder();
+        mCurrentDreamToken = newToken;
+        mCurrentDreamName = name;
+        mCurrentDreamIsTest = isTest;
+        mCurrentDreamUserId = userId;
+
+        mHandler.post(new Runnable() {
+            @Override
+            public void run() {
+                mController.startDream(newToken, name, isTest, userId);
+            }
+        });
+    }
+
+    private void stopDreamLocked() {
+        if (mCurrentDreamToken != null) {
+            if (DEBUG) Slog.i(TAG, "Leaving dreamland.");
+
+            cleanupDreamLocked();
+
+            mHandler.post(new Runnable() {
+                @Override
+                public void run() {
+                    mController.stopDream();
+                }
+            });
+        }
+    }
+
+    private void cleanupDreamLocked() {
+        mCurrentDreamToken = null;
+        mCurrentDreamName = null;
+        mCurrentDreamIsTest = false;
+        mCurrentDreamUserId = 0;
+    }
+
+    private void checkPermission(String permission) {
+        if (mContext.checkCallingOrSelfPermission(permission)
+                != PackageManager.PERMISSION_GRANTED) {
+            throw new SecurityException("Access denied to process: " + Binder.getCallingPid()
+                    + ", must have permission " + permission);
+        }
+    }
+
+    private static String componentsToString(ComponentName[] componentNames) {
+        StringBuilder names = new StringBuilder();
+        if (componentNames != null) {
+            for (ComponentName componentName : componentNames) {
+                if (names.length() > 0) {
+                    names.append(',');
+                }
+                names.append(componentName.flattenToString());
+            }
+        }
+        return names.toString();
+    }
+
+    private static ComponentName[] componentsFromString(String names) {
+        if (names == null) {
+            return null;
+        }
+        String[] namesArray = names.split(",");
+        ComponentName[] componentNames = new ComponentName[namesArray.length];
+        for (int i = 0; i < namesArray.length; i++) {
+            componentNames[i] = ComponentName.unflattenFromString(namesArray[i]);
+        }
+        return componentNames;
+    }
+
+    private final DreamController.Listener mControllerListener = new DreamController.Listener() {
+        @Override
+        public void onDreamStopped(Binder token) {
+            synchronized (mLock) {
+                if (mCurrentDreamToken == token) {
+                    cleanupDreamLocked();
+                }
+            }
+        }
+    };
+
+    /**
+     * Handler for asynchronous operations performed by the dream manager.
+     * Ensures operations to {@link DreamController} are single-threaded.
+     */
+    private final class DreamHandler extends Handler {
+        public DreamHandler(Looper looper) {
+            super(looper, null, true /*async*/);
+        }
+    }
+
+    private final class BinderService extends IDreamManager.Stub {
+        @Override // Binder call
+        protected void dump(FileDescriptor fd, PrintWriter pw, String[] args) {
+            if (mContext.checkCallingOrSelfPermission(Manifest.permission.DUMP)
+                    != PackageManager.PERMISSION_GRANTED) {
+                pw.println("Permission Denial: can't dump DreamManager from from pid="
+                        + Binder.getCallingPid()
+                        + ", uid=" + Binder.getCallingUid());
+                return;
+            }
+
+            final long ident = Binder.clearCallingIdentity();
+            try {
+                dumpInternal(pw);
+            } finally {
+                Binder.restoreCallingIdentity(ident);
+            }
+        }
+
+        @Override // Binder call
+        public ComponentName[] getDreamComponents() {
+            checkPermission(android.Manifest.permission.READ_DREAM_STATE);
+
+            final int userId = UserHandle.getCallingUserId();
+            final long ident = Binder.clearCallingIdentity();
+            try {
+                return getDreamComponentsForUser(userId);
+            } finally {
+                Binder.restoreCallingIdentity(ident);
+            }
+        }
+
+        @Override // Binder call
+        public void setDreamComponents(ComponentName[] componentNames) {
+            checkPermission(android.Manifest.permission.WRITE_DREAM_STATE);
+
+            final int userId = UserHandle.getCallingUserId();
+            final long ident = Binder.clearCallingIdentity();
+            try {
+                setDreamComponentsForUser(userId, componentNames);
+            } finally {
+                Binder.restoreCallingIdentity(ident);
+            }
+        }
+
+        @Override // Binder call
+        public ComponentName getDefaultDreamComponent() {
+            checkPermission(android.Manifest.permission.READ_DREAM_STATE);
+
+            final int userId = UserHandle.getCallingUserId();
+            final long ident = Binder.clearCallingIdentity();
+            try {
+                return getDefaultDreamComponentForUser(userId);
+            } finally {
+                Binder.restoreCallingIdentity(ident);
+            }
+        }
+
+        @Override // Binder call
+        public boolean isDreaming() {
+            checkPermission(android.Manifest.permission.READ_DREAM_STATE);
+
+            final long ident = Binder.clearCallingIdentity();
+            try {
+                return isDreamingInternal();
+            } finally {
+                Binder.restoreCallingIdentity(ident);
+            }
+        }
+
+        @Override // Binder call
+        public void dream() {
+            checkPermission(android.Manifest.permission.WRITE_DREAM_STATE);
+
+            final long ident = Binder.clearCallingIdentity();
+            try {
+                requestDreamInternal();
+            } finally {
+                Binder.restoreCallingIdentity(ident);
+            }
+        }
+
+        @Override // Binder call
+        public void testDream(ComponentName dream) {
+            if (dream == null) {
+                throw new IllegalArgumentException("dream must not be null");
+            }
+            checkPermission(android.Manifest.permission.WRITE_DREAM_STATE);
+
+            final int callingUserId = UserHandle.getCallingUserId();
+            final int currentUserId = ActivityManager.getCurrentUser();
+            if (callingUserId != currentUserId) {
+                // This check is inherently prone to races but at least it's something.
+                Slog.w(TAG, "Aborted attempt to start a test dream while a different "
+                        + " user is active: callingUserId=" + callingUserId
+                        + ", currentUserId=" + currentUserId);
+                return;
+            }
+            final long ident = Binder.clearCallingIdentity();
+            try {
+                testDreamInternal(dream, callingUserId);
+            } finally {
+                Binder.restoreCallingIdentity(ident);
+            }
+        }
+
+        @Override // Binder call
+        public void awaken() {
+            checkPermission(android.Manifest.permission.WRITE_DREAM_STATE);
+
+            final long ident = Binder.clearCallingIdentity();
+            try {
+                requestAwakenInternal();
+            } finally {
+                Binder.restoreCallingIdentity(ident);
+            }
+        }
+
+        @Override // Binder call
+        public void finishSelf(IBinder token) {
+            // Requires no permission, called by Dream from an arbitrary process.
+            if (token == null) {
+                throw new IllegalArgumentException("token must not be null");
+            }
+
+            final long ident = Binder.clearCallingIdentity();
+            try {
+                finishSelfInternal(token);
+            } finally {
+                Binder.restoreCallingIdentity(ident);
+            }
+        }
+    }
+
+    private final class LocalService extends DreamManagerInternal {
+        @Override
+        public void startDream() {
+            startDreamInternal();
+        }
+
+        @Override
+        public void stopDream() {
+            stopDreamInternal();
+        }
+
+        @Override
+        public boolean isDreaming() {
+            return isDreamingInternal();
+        }
+    }
+}