Add functionality to overwrite the /etc/preloaded-classes file.

* Requires root, disable-verity, reboot, root before use.

Test: manual through UI and sequencing
Change-Id: I68965334776e130b8220a5814b2525109cf96800

3 files changed, 144 insertions, 38 deletions

diff --git a/tools/preload2/src/com/android/preload/DeviceUtils.java b/tools/preload2/src/com/android/preload/DeviceUtils.java
index 803a7f195a59..18cab7bee12d 100644
--- a/tools/preload2/src/com/android/preload/DeviceUtils.java
+++ b/tools/preload2/src/com/android/preload/DeviceUtils.java
@@ -16,13 +16,18 @@
 
 package com.android.preload;
 
+import com.android.ddmlib.AdbCommandRejectedException;
 import com.android.ddmlib.AndroidDebugBridge;
 import com.android.ddmlib.AndroidDebugBridge.IDeviceChangeListener;
 import com.android.preload.classdataretrieval.hprof.Hprof;
 import com.android.ddmlib.DdmPreferences;
 import com.android.ddmlib.IDevice;
 import com.android.ddmlib.IShellOutputReceiver;
+import com.android.ddmlib.SyncException;
+import com.android.ddmlib.TimeoutException;
 
+import java.io.File;
+import java.io.IOException;
 import java.util.Date;
 import java.util.concurrent.Future;
 import java.util.concurrent.TimeUnit;
@@ -32,6 +37,18 @@ import java.util.concurrent.TimeUnit;
  */
 public class DeviceUtils {
 
+  // Locations
+  private static final String PRELOADED_CLASSES_FILE = "/etc/preloaded-classes";
+  // Shell commands
+  private static final String CREATE_EMPTY_PRELOADED_CMD = "touch " + PRELOADED_CLASSES_FILE;
+  private static final String DELETE_CACHE_CMD = "rm /data/dalvik-cache/*/*boot.art";
+  private static final String DELETE_PRELOADED_CMD = "rm " + PRELOADED_CLASSES_FILE;
+  private static final String READ_PRELOADED_CMD = "cat " + PRELOADED_CLASSES_FILE;
+  private static final String START_SHELL_CMD = "start";
+  private static final String STOP_SHELL_CMD = "stop";
+  private static final String REMOUNT_SYSTEM_CMD = "mount -o rw,remount /system";
+  private static final String UNSET_BOOTCOMPLETE_CMD = "setprop dev.bootcomplete \"0\"";
+
   public static void init(int debugPort) {
     DdmPreferences.setSelectedDebugPort(debugPort);
 
@@ -119,43 +136,56 @@ public class DeviceUtils {
     return !ret.contains("No such file or directory");
   }
 
-  /**
-   * Remove files involved in a standard build that interfere with collecting data. This will
-   * remove /etc/preloaded-classes, which determines which classes are allocated already in the
-   * boot image. It also deletes any compiled boot image on the device. Then it restarts the
-   * device.
-   *
-   * This is a potentially long-running operation, as the boot after the deletion may take a while.
-   * The method will abort after the given timeout.
-   */
-  public static boolean removePreloaded(IDevice device, long preloadedWaitTimeInSeconds) {
-    String oldContent =
-        DeviceUtils.doShellReturnString(device, "cat /etc/preloaded-classes", 1, TimeUnit.SECONDS);
-    if (oldContent.trim().equals("")) {
-      System.out.println("Preloaded-classes already empty.");
-      return true;
-    }
-
-    // Stop the system server etc.
-    doShell(device, "stop", 100, TimeUnit.MILLISECONDS);
-
-    // Remount /system, delete /etc/preloaded-classes. It would be nice to use "adb remount,"
-    // but AndroidDebugBridge doesn't expose it.
-    doShell(device, "mount -o remount,rw /system", 500, TimeUnit.MILLISECONDS);
-    doShell(device, "rm /etc/preloaded-classes", 100, TimeUnit.MILLISECONDS);
-    // We do need an empty file.
-    doShell(device, "touch /etc/preloaded-classes", 100, TimeUnit.MILLISECONDS);
-
-    // Delete the files in the dalvik cache.
-    doShell(device, "rm /data/dalvik-cache/*/*boot.art", 500, TimeUnit.MILLISECONDS);
-
-    // We'll try to use dev.bootcomplete to know when the system server is back up. But stop
-    // doesn't reset it, so do it manually.
-    doShell(device, "setprop dev.bootcomplete \"0\"", 500, TimeUnit.MILLISECONDS);
+    /**
+     * Write over the preloaded-classes file with an empty or existing file and regenerate the boot
+     * image as necessary.
+     *
+     * @param device
+     * @param pcFile
+     * @param bootTimeout
+     * @throws AdbCommandRejectedException
+     * @throws IOException
+     * @throws TimeoutException
+     * @throws SyncException
+     * @return true if successfully overwritten, false otherwise
+     */
+    public static boolean overwritePreloaded(IDevice device, File pcFile, long bootTimeout)
+            throws AdbCommandRejectedException, IOException, TimeoutException, SyncException {
+        boolean writeEmpty = (pcFile == null);
+        if (writeEmpty) {
+            // Check if the preloaded-classes file is already empty.
+            String oldContent =
+                    doShellReturnString(device, READ_PRELOADED_CMD, 1, TimeUnit.SECONDS);
+            if (oldContent.trim().equals("")) {
+                System.out.println("Preloaded-classes already empty.");
+                return true;
+            }
+        }
 
-    // Start the system server.
-    doShell(device, "start", 100, TimeUnit.MILLISECONDS);
+        // Stop the system server etc.
+        doShell(device, STOP_SHELL_CMD, 1, TimeUnit.SECONDS);
+        // Remount the read-only system partition
+        doShell(device, REMOUNT_SYSTEM_CMD, 1, TimeUnit.SECONDS);
+        // Delete the preloaded-classes file
+        doShell(device, DELETE_PRELOADED_CMD, 1, TimeUnit.SECONDS);
+        // Delete the dalvik cache files
+        doShell(device, DELETE_CACHE_CMD, 1, TimeUnit.SECONDS);
+        if (writeEmpty) {
+            // Write an empty preloaded-classes file
+            doShell(device, CREATE_EMPTY_PRELOADED_CMD, 500, TimeUnit.MILLISECONDS);
+        } else {
+            // Push the new preloaded-classes file
+            device.pushFile(pcFile.getAbsolutePath(), PRELOADED_CLASSES_FILE);
+        }
+        // Manually reset the boot complete flag
+        doShell(device, UNSET_BOOTCOMPLETE_CMD, 1, TimeUnit.SECONDS);
+        // Restart system server on the device
+        doShell(device, START_SHELL_CMD, 1, TimeUnit.SECONDS);
+        // Wait for the boot complete flag and return the outcome.
+        return waitForBootComplete(device, bootTimeout);
+  }
 
+  private static boolean waitForBootComplete(IDevice device, long timeout) {
     // Do a loop checking each second whether bootcomplete. Wait for at most the given
     // threshold.
     Date startDate = new Date();
@@ -178,7 +208,7 @@ public class DeviceUtils {
       Date endDate = new Date();
       long seconds =
           TimeUnit.SECONDS.convert(endDate.getTime() - startDate.getTime(), TimeUnit.MILLISECONDS);
-      if (seconds > preloadedWaitTimeInSeconds) {
+      if (seconds > timeout) {
         return false;
       }
     }
diff --git a/tools/preload2/src/com/android/preload/Main.java b/tools/preload2/src/com/android/preload/Main.java
index c42a19b58811..2265e9557c4b 100644
--- a/tools/preload2/src/com/android/preload/Main.java
+++ b/tools/preload2/src/com/android/preload/Main.java
@@ -29,6 +29,7 @@ import com.android.preload.actions.RunMonkeyAction;
 import com.android.preload.actions.ScanAllPackagesAction;
 import com.android.preload.actions.ScanPackageAction;
 import com.android.preload.actions.ShowDataAction;
+import com.android.preload.actions.WritePreloadedClassesAction;
 import com.android.preload.classdataretrieval.ClassDataRetriever;
 import com.android.preload.classdataretrieval.hprof.Hprof;
 import com.android.preload.classdataretrieval.jdwp.JDWPClassDataRetriever;
@@ -96,6 +97,7 @@ public class Main {
     public final static String COMPUTE_FILE_CMD = "comp";
     public final static String EXPORT_CMD = "export";
     public final static String IMPORT_CMD = "import";
+    public final static String WRITE_CMD = "write";
 
     /**
      * @param args
@@ -132,6 +134,7 @@ public class Main {
                 null));
         actions.add(new ComputeThresholdXAction("Compute(X)", dataTableModel,
                 CLASS_PRELOAD_BLACKLIST));
+        actions.add(new WritePreloadedClassesAction(clientUtils, null, dataTableModel));
         actions.add(new ShowDataAction(dataTableModel));
         actions.add(new ImportAction(dataTableModel));
         actions.add(new ExportAction(dataTableModel));
@@ -200,6 +203,11 @@ public class Main {
                     ui.input(it.next());
                     ui.confirmYes();
                     ui.output(new File(it.next()));
+                // Operation: Write preloaded classes from a specific file
+                } else if (WRITE_CMD.equals(op)) {
+                    System.out.println("Writing preloaded classes.");
+                    ui.action(WritePreloadedClassesAction.class);
+                    ui.input(new File(it.next()));
                 }
             }
         } catch (NoSuchElementException e) {
@@ -305,8 +313,16 @@ public class Main {
 
             Main.getUI().showMessageDialog("The device will reboot. This will potentially take a "
                     + "long time. Please be patient.");
-            if (!DeviceUtils.removePreloaded(device, 15 * 60) /* 15m timeout */) {
-                Main.getUI().showMessageDialog("Removing preloaded-classes failed unexpectedly!");
+            boolean success = false;
+            try {
+                success = DeviceUtils.overwritePreloaded(device, null, 15 * 60);
+            } catch (Exception e) {
+                System.err.println(e);
+            } finally {
+                if (!success) {
+                    Main.getUI().showMessageDialog(
+                            "Removing preloaded-classes failed unexpectedly!");
+                }
             }
         }
     }
diff --git a/tools/preload2/src/com/android/preload/actions/WritePreloadedClassesAction.java b/tools/preload2/src/com/android/preload/actions/WritePreloadedClassesAction.java
new file mode 100644
index 000000000000..9b97f1168df9
--- /dev/null
+++ b/tools/preload2/src/com/android/preload/actions/WritePreloadedClassesAction.java
@@ -0,0 +1,60 @@
+/*
+ * Copyright (C) 2015 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.preload.actions;
+
+import com.android.ddmlib.Client;
+import com.android.ddmlib.IDevice;
+import com.android.preload.ClientUtils;
+import com.android.preload.DeviceUtils;
+import com.android.preload.DumpData;
+import com.android.preload.DumpTableModel;
+import com.android.preload.Main;
+
+import java.awt.event.ActionEvent;
+import java.io.File;
+import java.util.Date;
+import java.util.Map;
+
+public class WritePreloadedClassesAction extends AbstractThreadedDeviceSpecificAction {
+    private File preloadedClassFile;
+
+    public WritePreloadedClassesAction(ClientUtils utils, IDevice device, DumpTableModel dataTableModel) {
+        super("Write preloaded classes action", device);
+    }
+
+    @Override
+    public void actionPerformed(ActionEvent e) {
+        File[] files = Main.getUI().showOpenDialog(true);
+        if (files != null && files.length > 0) {
+            preloadedClassFile = files[0];
+            super.actionPerformed(e);
+        }
+    }
+
+    @Override
+    public void run() {
+        Main.getUI().showWaitDialog();
+        try {
+            // Write the new file with a 5-minute timeout
+            DeviceUtils.overwritePreloaded(device, preloadedClassFile, 5 * 60);
+        } catch (Exception e) {
+            System.err.println(e);
+        } finally {
+            Main.getUI().hideWaitDialog();
+        }
+    }
+}