Code to migrate a single directory from the old sandbox to the new.

webkit/fileapi/obfuscated_file_system_file_util.h

Index: webkit/fileapi/obfuscated_file_system_file_util.h
diff --git a/webkit/fileapi/obfuscated_file_system_file_util.h b/webkit/fileapi/obfuscated_file_system_file_util.h
index c6a4498e338c31619437fc1eb34610a78561e530..529899ea0e5d482f461067bad188f815b14a93d2 100644
--- a/webkit/fileapi/obfuscated_file_system_file_util.h
+++ b/webkit/fileapi/obfuscated_file_system_file_util.h
@@ -41,6 +41,9 @@ class FileSystemOperationContext;
 // SandboxMountPointProvider [and the task it uses to drop the reference] and
 // SandboxMountPointProvider::GetFileSystemRootPathTask.  Without that last one,
 // we wouldn't need ref counting.
+//
+// TODO(ericu): We don't ever update directory mtimes; which operations should
+// do that?
 class ObfuscatedFileSystemFileUtil : public FileSystemFileUtil,
     public base::RefCountedThreadSafe<ObfuscatedFileSystemFileUtil> {
  public:
@@ -131,6 +134,21 @@ class ObfuscatedFileSystemFileUtil : public FileSystemFileUtil,
   // about migration; TODO(ericu): implement migration and fix these comments.
   FilePath GetDirectoryForOrigin(const GURL& origin, bool create);
 
+  // This will migrate a filesystem from the old passthrough sandbox into the
+  // new obfuscated one.  It won't obfuscate the old filenames [it will maintain
+  // the old structure, but move it to a new root], but any new files created
+  // will go into the new standard locations.  This will be completely
+  // transparent to the user.  This migration is atomic in that it won't alter
+  // the source data until it's done, and that will be with a single directory
+  // move [the directory with the unguessable name will move into the new
+  // filesystem storage directory].  However, if this fails partway through, it
+  // might leave a seemingly-valid database for this origin.  When it starts up,
+  // it will clear any such database, just in case.
+  bool MigrateFromOldSandbox(
+      const GURL& origin, FileSystemType type, const FilePath& root);
+
+  FilePath::StringType GetDirectoryNameForType(FileSystemType type) const;
+
  protected:
   virtual AbstractFileEnumerator* CreateFileEnumerator(
       FileSystemOperationContext* context,
@@ -153,18 +171,29 @@ class ObfuscatedFileSystemFileUtil : public FileSystemFileUtil,
   base::PlatformFileError CreateFile(
       FileSystemOperationContext* context,
       const GURL& origin_url, FileSystemType type,
-      FileInfo* file_info,
+      const FilePath& source_path, FileInfo* file_info,
       int file_flags, base::PlatformFile* handle);
   // Given the filesystem's root URL and a virtual path, produces a real, full
-  // local path to the underlying data file.
+  // local path to the underlying data file.  This does a database lookup, and
+  // verifies that the file exists.
   FilePath GetLocalPath(
       const GURL& origin_url,
       FileSystemType type,
       const FilePath& virtual_path);
+  // This converts from a relative path [as is stored in the FileInfo.data_path
+  // field] to an absolute local path that can be given to the operating system.
+  // It does no checks as to whether the file actually exists; it's pure path
+  // manipulation.
+  FilePath DataPathToLocalPath(
+      const GURL& origin, FileSystemType type, const FilePath& virtual_path);

[michaeln, 2011/05/20 02:15:16]

virtual_path s/b data_path in the arg list

[ericu, 2011/05/20 02:23:25]

Done.

+  // This does the reverse of DataPathToLocalPath.
+  FilePath LocalPathToDataPath(
+      const GURL& origin, FileSystemType type, const FilePath& data_path);
   FileSystemDirectoryDatabase* GetDirectoryDatabase(
       const GURL& origin_url, FileSystemType type);
   void MarkUsed();
   void DropDatabases();
+  bool DestroyDirectoryDatabase(const GURL& origin, FileSystemType type);
 
   typedef std::map<std::string, FileSystemDirectoryDatabase*> DirectoryMap;
   DirectoryMap directories_;