1/*
2 * Copyright 2016 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
17package android.os;
18
19import android.content.Context;
20import android.content.pm.ApplicationInfo;
21import android.content.pm.PackageManager;
22import android.opengl.EGL14;
23import android.os.Build;
24import android.os.SystemProperties;
25import android.provider.Settings;
26import android.util.Log;
27
28import dalvik.system.VMRuntime;
29
30import java.io.File;
31
32/** @hide */
33public class GraphicsEnvironment {
34
35    private static final GraphicsEnvironment sInstance = new GraphicsEnvironment();
36
37    /**
38     * Returns the shared {@link GraphicsEnvironment} instance.
39     */
40    public static GraphicsEnvironment getInstance() {
41        return sInstance;
42    }
43
44    private static final boolean DEBUG = false;
45    private static final String TAG = "GraphicsEnvironment";
46    private static final String PROPERTY_GFX_DRIVER = "ro.gfx.driver.0";
47
48    private ClassLoader mClassLoader;
49    private String mLayerPath;
50    private String mDebugLayerPath;
51
52    /**
53     * Set up GraphicsEnvironment
54     */
55    public void setup(Context context) {
56        setupGpuLayers(context);
57        chooseDriver(context);
58    }
59
60    /**
61     * Check whether application is debuggable
62     */
63    private static boolean isDebuggable(Context context) {
64        return (context.getApplicationInfo().flags & ApplicationInfo.FLAG_DEBUGGABLE) > 0;
65    }
66
67    /**
68     * Store the layer paths available to the loader.
69     */
70    public void setLayerPaths(ClassLoader classLoader,
71                              String layerPath,
72                              String debugLayerPath) {
73        // We have to store these in the class because they are set up before we
74        // have access to the Context to properly set up GraphicsEnvironment
75        mClassLoader = classLoader;
76        mLayerPath = layerPath;
77        mDebugLayerPath = debugLayerPath;
78    }
79
80    /**
81     * Set up layer search paths for all apps
82     * If debuggable, check for additional debug settings
83     */
84    private void setupGpuLayers(Context context) {
85
86        String layerPaths = "";
87
88        // Only enable additional debug functionality if the following conditions are met:
89        // 1. App is debuggable
90        // 2. ENABLE_GPU_DEBUG_LAYERS is true
91        // 3. Package name is equal to GPU_DEBUG_APP
92
93        if (isDebuggable(context)) {
94
95            int enable = Settings.Global.getInt(context.getContentResolver(),
96                                                Settings.Global.ENABLE_GPU_DEBUG_LAYERS, 0);
97
98            if (enable != 0) {
99
100                String gpuDebugApp = Settings.Global.getString(context.getContentResolver(),
101                                                               Settings.Global.GPU_DEBUG_APP);
102
103                String packageName = context.getPackageName();
104
105                if ((gpuDebugApp != null && packageName != null)
106                        && (!gpuDebugApp.isEmpty() && !packageName.isEmpty())
107                        && gpuDebugApp.equals(packageName)) {
108                    Log.i(TAG, "GPU debug layers enabled for " + packageName);
109
110                    // Prepend the debug layer path as a searchable path.
111                    // This will ensure debug layers added will take precedence over
112                    // the layers specified by the app.
113                    layerPaths = mDebugLayerPath + ":";
114
115                    String layers = Settings.Global.getString(context.getContentResolver(),
116                                                              Settings.Global.GPU_DEBUG_LAYERS);
117
118                    Log.i(TAG, "Debug layer list: " + layers);
119                    if (layers != null && !layers.isEmpty()) {
120                        setDebugLayers(layers);
121                    }
122                }
123            }
124
125        }
126
127        // Include the app's lib directory in all cases
128        layerPaths += mLayerPath;
129
130        setLayerPaths(mClassLoader, layerPaths);
131    }
132
133    /**
134     * Choose whether the current process should use the builtin or an updated driver.
135     */
136    private static void chooseDriver(Context context) {
137        String driverPackageName = SystemProperties.get(PROPERTY_GFX_DRIVER);
138        if (driverPackageName == null || driverPackageName.isEmpty()) {
139            return;
140        }
141        // To minimize risk of driver updates crippling the device beyond user repair, never use an
142        // updated driver for privileged or non-updated system apps. Presumably pre-installed apps
143        // were tested thoroughly with the pre-installed driver.
144        ApplicationInfo ai = context.getApplicationInfo();
145        if (ai.isPrivilegedApp() || (ai.isSystemApp() && !ai.isUpdatedSystemApp())) {
146            if (DEBUG) Log.v(TAG, "ignoring driver package for privileged/non-updated system app");
147            return;
148        }
149        ApplicationInfo driverInfo;
150        try {
151            driverInfo = context.getPackageManager().getApplicationInfo(driverPackageName,
152                    PackageManager.MATCH_SYSTEM_ONLY);
153        } catch (PackageManager.NameNotFoundException e) {
154            Log.w(TAG, "driver package '" + driverPackageName + "' not installed");
155            return;
156        }
157        String abi = chooseAbi(driverInfo);
158        if (abi == null) {
159            if (DEBUG) {
160                // This is the normal case for the pre-installed empty driver package, don't spam
161                if (driverInfo.isUpdatedSystemApp()) {
162                    Log.w(TAG, "updated driver package has no compatible native libraries");
163                }
164            }
165            return;
166        }
167        if (driverInfo.targetSdkVersion < Build.VERSION_CODES.O) {
168            // O drivers are restricted to the sphal linker namespace, so don't try to use
169            // packages unless they declare they're compatible with that restriction.
170            Log.w(TAG, "updated driver package is not known to be compatible with O");
171            return;
172        }
173
174        StringBuilder sb = new StringBuilder();
175        sb.append(driverInfo.nativeLibraryDir)
176          .append(File.pathSeparator);
177        sb.append(driverInfo.sourceDir)
178          .append("!/lib/")
179          .append(abi);
180        String paths = sb.toString();
181
182        if (DEBUG) Log.v(TAG, "gfx driver package libs: " + paths);
183        setDriverPath(paths);
184    }
185
186    /**
187     * Start a background thread to initialize EGL.
188     *
189     * Initializing EGL involves loading and initializing the graphics driver. Some drivers take
190     * several 10s of milliseconds to do this, so doing it on-demand when an app tries to render
191     * its first frame adds directly to user-visible app launch latency. By starting it earlier
192     * on a separate thread, it can usually be finished well before the UI is ready to be drawn.
193     *
194     * Should only be called after chooseDriver().
195     */
196    public static void earlyInitEGL() {
197        Thread eglInitThread = new Thread(
198                () -> {
199                    EGL14.eglGetDisplay(EGL14.EGL_DEFAULT_DISPLAY);
200                },
201                "EGL Init");
202        eglInitThread.start();
203    }
204
205    private static String chooseAbi(ApplicationInfo ai) {
206        String isa = VMRuntime.getCurrentInstructionSet();
207        if (ai.primaryCpuAbi != null &&
208                isa.equals(VMRuntime.getInstructionSet(ai.primaryCpuAbi))) {
209            return ai.primaryCpuAbi;
210        }
211        if (ai.secondaryCpuAbi != null &&
212                isa.equals(VMRuntime.getInstructionSet(ai.secondaryCpuAbi))) {
213            return ai.secondaryCpuAbi;
214        }
215        return null;
216    }
217
218    private static native void setLayerPaths(ClassLoader classLoader, String layerPaths);
219    private static native void setDebugLayers(String layers);
220    private static native void setDriverPath(String path);
221}
222