Add logging for error conditions when reading or writing backup enabled

state.

Also add debug logging when reading or writing backup enabled state to
be able to better investigate bugs.

Bug: 148587496
Bug: 147352819

Test: atest -v RunBackupFrameworksServicesRoboTests
Test: atest -v $(find frameworks/base/services/tests/servicestests/src/com/android/server/backup -name '\''*Test.java'\'')'
Change-Id: I3c9b158ce57558daa5437cebe6aa0a0c924692fc

1 files changed, 14 insertions, 6 deletions

diff --git a/services/backup/java/com/android/server/backup/UserBackupManagerFilePersistedSettings.java b/services/backup/java/com/android/server/backup/UserBackupManagerFilePersistedSettings.java
index 6a1de6378a5e..205b7dda267e 100644
--- a/services/backup/java/com/android/server/backup/UserBackupManagerFilePersistedSettings.java
+++ b/services/backup/java/com/android/server/backup/UserBackupManagerFilePersistedSettings.java
@@ -16,7 +16,6 @@
 
 package com.android.server.backup;
 
-import static com.android.server.backup.BackupManagerService.DEBUG;
 import static com.android.server.backup.BackupManagerService.TAG;
 
 import android.util.Slog;
@@ -33,10 +32,13 @@ final class UserBackupManagerFilePersistedSettings {
     private static final String BACKUP_ENABLE_FILE = "backup_enabled";
 
     static boolean readBackupEnableState(int userId) {
-        return readBackupEnableState(UserBackupManagerFiles.getBaseStateDir(userId));
+        boolean enabled = readBackupEnableState(UserBackupManagerFiles.getBaseStateDir(userId));
+        Slog.d(TAG, "user:" + userId + " readBackupEnableState enabled:" + enabled);
+        return enabled;
     }
 
     static void writeBackupEnableState(int userId, boolean enable) {
+        Slog.d(TAG, "user:" + userId + " writeBackupEnableState enable:" + enable);
         writeBackupEnableState(UserBackupManagerFiles.getBaseStateDir(userId), enable);
     }
 
@@ -45,15 +47,17 @@ final class UserBackupManagerFilePersistedSettings {
         if (enableFile.exists()) {
             try (FileInputStream fin = new FileInputStream(enableFile)) {
                 int state = fin.read();
+                if (state != 0 && state != 1) {
+                    // TODO (b/148587496) handle instead of only logging
+                    Slog.e(TAG, "Unexpected enabled state:" + state);
+                }
                 return state != 0;
             } catch (IOException e) {
                 // can't read the file; fall through to assume disabled
                 Slog.e(TAG, "Cannot read enable state; assuming disabled");
             }
         } else {
-            if (DEBUG) {
-                Slog.i(TAG, "isBackupEnabled() => false due to absent settings file");
-            }
+            Slog.i(TAG, "isBackupEnabled() => false due to absent settings file");
         }
         return false;
     }
@@ -64,7 +68,11 @@ final class UserBackupManagerFilePersistedSettings {
         try (FileOutputStream fout = new FileOutputStream(stage)) {
             fout.write(enable ? 1 : 0);
             fout.close();
-            stage.renameTo(enableFile);
+            boolean renamed = stage.renameTo(enableFile);
+            if (!renamed) {
+                // TODO (b/148587496) handle instead of only logging
+                Slog.e(TAG, "Write enable failed as could not rename staging file to actual");
+            }
             // will be synced immediately by the try-with-resources call to close()
         } catch (IOException | RuntimeException e) {
             Slog.e(