From c05d87817a26488ea0989f17cae3fac2a2b884b7 Mon Sep 17 00:00:00 2001
From: Lucas Rocha <lucasr@mozilla.com>
Date: Tue, 24 Apr 2012 16:34:03 -0400
Subject: [PATCH] Bug 746444 - Force unlock database file when database is
 opened in read-only mode (r=blassey)

---
 .../android/base/db/BrowserProvider.java.in   | 32 +++++++++++++++++++
 1 file changed, 32 insertions(+)

diff --git a/mobile/android/base/db/BrowserProvider.java.in b/mobile/android/base/db/BrowserProvider.java.in
index c3cbb1ee04e..a2f908b5732 100644
--- a/mobile/android/base/db/BrowserProvider.java.in
+++ b/mobile/android/base/db/BrowserProvider.java.in
@@ -21,6 +21,7 @@ import java.util.Random;
 import java.util.regex.Pattern;
 import java.util.regex.Matcher;
 
+import org.mozilla.gecko.GeckoAppShell;
 import org.mozilla.gecko.GeckoBackgroundThread;
 import org.mozilla.gecko.GeckoProfile;
 import org.mozilla.gecko.R;
@@ -946,6 +947,35 @@ public class BrowserProvider extends ContentProvider {
         }
     }
 
+    private void ensureDatabaseIsNotLocked(DatabaseHelper dbHelper, String profile, boolean isTest) {
+        SQLiteDatabase db = dbHelper.getWritableDatabase();
+
+        // The returned writable database is read-only, this probably means that the
+        // database is permanently locked due to a crash or a non-clean quit in Fennec.
+        // We can assume it's safe to forcefully unlock the database file in this case
+        // as all database access happens through this content provider (see bug 741718).
+        if (db.isReadOnly()) {
+            debug("Database is in read-only mode, trying to forcefully unlock the database file");
+
+            // Close read-only connection, we don't want to use it
+            dbHelper.close();
+
+            // When running inside a test or on Android releases older than 8,
+            // the returned database path is just filename, not the full path.
+            // We need to full path when unlocking the database.
+            String databasePath = getDatabasePath(profile, false);
+            if (isTest || Build.VERSION.SDK_INT <= 8) {
+                databasePath = mContext.getDatabasePath(databasePath).getAbsolutePath();
+            }
+
+            // Forcefully unlock the database file
+            GeckoAppShell.unlockDatabaseFile(databasePath);
+
+            // TODO: maybe check if the connection is still read-only and let the
+            // user know that the device needs rebooting?
+        }
+    }
+
     private DatabaseHelper getDatabaseHelperForProfile(String profile, boolean isTest) {
         // Each profile has a separate browser.db database. The target
         // profile is provided using a URI query argument in each request
@@ -964,6 +994,8 @@ public class BrowserProvider extends ContentProvider {
             }
             dbHelper = new DatabaseHelper(getContext(), getDatabasePath(profile, isTest));
             mDatabasePerProfile.put(profile, dbHelper);
+
+            ensureDatabaseIsNotLocked(dbHelper, profile, isTest);
         }
 
         debug("Created database helper for profile: " + profile);