cp preopted files from B partition during PM init.

This allows us to save space on the system partition while still
having access to the preopted files.

We do this on first boot when the "ro.cp_system_other_odex" property
is set to 1. We do this during package manager initialization before
scanning the system to see which apks need to be optimized again.

Note that a separate script, run by init, is actually responsible for
finding and copying the files. We simply request that it runs.

Bug: 29278988

Change-Id: I8d7c790ad35b32a0ce1d87939f043419bae4d88a
diff --git a/services/core/java/com/android/server/pm/PackageManagerService.java b/services/core/java/com/android/server/pm/PackageManagerService.java
index fe492c7..410ec38 100644
--- a/services/core/java/com/android/server/pm/PackageManagerService.java
+++ b/services/core/java/com/android/server/pm/PackageManagerService.java
@@ -629,7 +629,7 @@
 
     final ProtectedPackages mProtectedPackages = new ProtectedPackages();
 
-    boolean mRestoredSettings;
+    boolean mFirstBoot;
 
     // System configuration read by SystemConfig.
     final int[] mGlobalGids;
@@ -2220,6 +2220,34 @@
         displayManager.getDisplay(Display.DEFAULT_DISPLAY).getMetrics(metrics);
     }
 
+    /**
+     * Requests that files preopted on a secondary system partition be copied to the data partition
+     * if possible.  Note that the actual copying of the files is accomplished by init for security
+     * reasons. This simply requests that the copy takes place and awaits confirmation of its
+     * completion. See platform/system/extras/cppreopt/ for the implementation of the actual copy.
+     */
+    private static void requestCopyPreoptedFiles() {
+        final int WAIT_TIME_MS = 100;
+        final String CP_PREOPT_PROPERTY = "sys.cppreopt";
+        if (SystemProperties.getInt("ro.cp_system_other_odex", 0) == 1) {
+            SystemProperties.set(CP_PREOPT_PROPERTY, "requested");
+            // We will wait for up to 100 seconds.
+            final long timeEnd = SystemClock.uptimeMillis() + 100 * 1000;
+            while (!SystemProperties.get(CP_PREOPT_PROPERTY).equals("finished")) {
+                try {
+                    Thread.sleep(WAIT_TIME_MS);
+                } catch (InterruptedException e) {
+                    // Do nothing
+                }
+                if (SystemClock.uptimeMillis() > timeEnd) {
+                    SystemProperties.set(CP_PREOPT_PROPERTY, "timed-out");
+                    Slog.wtf(TAG, "cppreopt did not finish!");
+                    break;
+                }
+            }
+        }
+    }
+
     public PackageManagerService(Context context, Installer installer,
             boolean factoryTest, boolean onlyCore) {
         EventLog.writeEvent(EventLogTags.BOOT_PROGRESS_PMS_START,
@@ -2321,7 +2349,11 @@
 
             mFoundPolicyFile = SELinuxMMAC.readInstallPolicy();
 
-            mRestoredSettings = mSettings.readLPw(sUserManager.getUsers(false));
+            mFirstBoot = !mSettings.readLPw(sUserManager.getUsers(false));
+
+            if (mFirstBoot) {
+                requestCopyPreoptedFiles();
+            }
 
             String customResolverActivity = Resources.getSystem().getString(
                     R.string.config_customResolverActivity);
@@ -2698,7 +2730,7 @@
             // If this is the first boot or an update from pre-M, and it is a normal
             // boot, then we need to initialize the default preferred apps across
             // all defined users.
-            if (!onlyCore && (mPromoteSystemApps || !mRestoredSettings)) {
+            if (!onlyCore && (mPromoteSystemApps || mFirstBoot)) {
                 for (UserInfo user : sUserManager.getUsers(true)) {
                     mSettings.applyDefaultPreferredAppsLPw(this, user.id);
                     applyFactoryDefaultBrowserLPw(user.id);
@@ -2856,7 +2888,7 @@
 
     @Override
     public boolean isFirstBoot() {
-        return !mRestoredSettings;
+        return mFirstBoot;
     }
 
     @Override