Add an API for deleting databases.

Add SQLiteDatabase.deleteDatabase to delete a database and all
of its auxiliary files.

This method is also used by Context.deleteDatabase and resolves issues
where auxiliary files would get left behind.

Bug: 5972489
Change-Id: I3633b9b4978972a1d240ac0a9861420ecf989149

2 files changed, 36 insertions, 1 deletions

diff --git a/core/java/android/app/ContextImpl.java b/core/java/android/app/ContextImpl.java
index 6d5cce5..e348b87 100644
--- a/core/java/android/app/ContextImpl.java
+++ b/core/java/android/app/ContextImpl.java
@@ -785,7 +785,7 @@ class ContextImpl extends Context {
     public boolean deleteDatabase(String name) {
         try {
             File f = validateFilePath(name, false);
-            return f.delete();
+            return SQLiteDatabase.deleteDatabase(f);
         } catch (Exception e) {
         }
         return false;
diff --git a/core/java/android/database/sqlite/SQLiteDatabase.java b/core/java/android/database/sqlite/SQLiteDatabase.java
index 515658f..2f3dc06 100644
--- a/core/java/android/database/sqlite/SQLiteDatabase.java
+++ b/core/java/android/database/sqlite/SQLiteDatabase.java
@@ -36,6 +36,7 @@ import android.util.Printer;
 import dalvik.system.CloseGuard;
 
 import java.io.File;
+import java.io.FileFilter;
 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.List;
@@ -678,6 +679,40 @@ public class SQLiteDatabase extends SQLiteClosable {
     }
 
     /**
+     * Deletes a database including its journal file and other auxiliary files
+     * that may have been created by the database engine.
+     *
+     * @param file The database file path.
+     * @return True if the database was successfully deleted.
+     */
+    public static boolean deleteDatabase(File file) {
+        if (file == null) {
+            throw new IllegalArgumentException("file must not be null");
+        }
+
+        boolean deleted = false;
+        deleted |= file.delete();
+        deleted |= new File(file.getPath() + "-journal").delete();
+        deleted |= new File(file.getPath() + "-shm").delete();
+        deleted |= new File(file.getPath() + "-wal").delete();
+
+        File dir = file.getParentFile();
+        if (dir != null) {
+            final String prefix = file.getName() + "-mj";
+            final FileFilter filter = new FileFilter() {
+                @Override
+                public boolean accept(File candidate) {
+                    return candidate.getName().startsWith(prefix);
+                }
+            };
+            for (File masterJournal : dir.listFiles(filter)) {
+                deleted |= masterJournal.delete();
+            }
+        }
+        return deleted;
+    }
+
+    /**
      * Reopens the database in read-write mode.
      * If the database is already read-write, does nothing.
      *