From c4bab9843ab936f9a9f134e2088a5bd891eb55c2 Mon Sep 17 00:00:00 2001
From: Jeff Sharkey <jsharkey@android.com>
Date: Mon, 1 Feb 2016 10:16:01 -0700
Subject: [PATCH] Only create custom database paths.

If the getDatabasePath() caller is using the default getDatabasesDir()
path, that method already handles possible path creation, so no
need for us to retry.

Also fix two small bugs that would have NPE'ed when listing files in
a directory that wasn't created.

Bug: 26895777
Change-Id: Iced16b05cfe95062717da8d0414c48daefcb5648
---
 core/java/android/app/ContextImpl.java | 20 ++++++++------------
 core/java/android/os/FileUtils.java    | 22 ++++++++++++++++++----
 2 files changed, 26 insertions(+), 16 deletions(-)

diff --git a/core/java/android/app/ContextImpl.java b/core/java/android/app/ContextImpl.java
index c5b5b0883774..89d4931b9fcb 100644
--- a/core/java/android/app/ContextImpl.java
+++ b/core/java/android/app/ContextImpl.java
@@ -182,8 +182,6 @@ class ContextImpl extends Context {
     @GuardedBy("mSync")
     private File[] mExternalMediaDirs;
 
-    private static final String[] EMPTY_STRING_ARRAY = {};
-
     // The system service cache for the system services that are cached per-ContextImpl.
     final Object[] mServiceCache = SystemServiceRegistry.createServiceCache();
 
@@ -627,8 +625,7 @@ class ContextImpl extends Context {
 
     @Override
     public String[] fileList() {
-        final String[] list = getFilesDir().list();
-        return (list != null) ? list : EMPTY_STRING_ARRAY;
+        return FileUtils.listOrEmpty(getFilesDir());
     }
 
     @Override
@@ -682,24 +679,23 @@ class ContextImpl extends Context {
             dir = new File(dirPath);
             name = name.substring(name.lastIndexOf(File.separatorChar));
             f = new File(dir, name);
+
+            if (!dir.isDirectory() && dir.mkdir()) {
+                FileUtils.setPermissions(dir.getPath(),
+                    FileUtils.S_IRWXU|FileUtils.S_IRWXG|FileUtils.S_IXOTH,
+                    -1, -1);
+            }
         } else {
             dir = getDatabasesDir();
             f = makeFilename(dir, name);
         }
 
-        if (!dir.isDirectory() && dir.mkdir()) {
-            FileUtils.setPermissions(dir.getPath(),
-                FileUtils.S_IRWXU|FileUtils.S_IRWXG|FileUtils.S_IXOTH,
-                -1, -1);
-        }
-
         return f;
     }
 
     @Override
     public String[] databaseList() {
-        final String[] list = getDatabasesDir().list();
-        return (list != null) ? list : EMPTY_STRING_ARRAY;
+        return FileUtils.listOrEmpty(getDatabasesDir());
     }
 
     private File getDatabasesDir() {
diff --git a/core/java/android/os/FileUtils.java b/core/java/android/os/FileUtils.java
index 290f7b3f16b8..c2aca419836a 100644
--- a/core/java/android/os/FileUtils.java
+++ b/core/java/android/os/FileUtils.java
@@ -29,6 +29,8 @@ import android.webkit.MimeTypeMap;
 
 import com.android.internal.annotations.VisibleForTesting;
 
+import libcore.util.EmptyArray;
+
 import java.io.BufferedInputStream;
 import java.io.ByteArrayOutputStream;
 import java.io.File;
@@ -658,8 +660,19 @@ public class FileUtils {
         }
     }
 
-    public static @NonNull File[] listFilesOrEmpty(File dir) {
-        File[] res = dir.listFiles();
+    public static @NonNull String[] listOrEmpty(@Nullable File dir) {
+        if (dir == null) return EmptyArray.STRING;
+        final String[] res = dir.list();
+        if (res != null) {
+            return res;
+        } else {
+            return EmptyArray.STRING;
+        }
+    }
+
+    public static @NonNull File[] listFilesOrEmpty(@Nullable File dir) {
+        if (dir == null) return EMPTY;
+        final File[] res = dir.listFiles();
         if (res != null) {
             return res;
         } else {
@@ -667,8 +680,9 @@ public class FileUtils {
         }
     }
 
-    public static @NonNull File[] listFilesOrEmpty(File dir, FilenameFilter filter) {
-        File[] res = dir.listFiles(filter);
+    public static @NonNull File[] listFilesOrEmpty(@Nullable File dir, FilenameFilter filter) {
+        if (dir == null) return EMPTY;
+        final File[] res = dir.listFiles(filter);
         if (res != null) {
             return res;
         } else {
-- 
2.11.0