Implement async verision of FileSystemFileUtil and in-memory file system for testing purposes.

webkit/chromeos/fileapi/file_util_async.h

+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef WEBKIT_FILEAPI_FILE_SYSTEM_FILE_UTIL_ASYNC_H_
+#define WEBKIT_FILEAPI_FILE_SYSTEM_FILE_UTIL_ASYNC_H_
+
+#include "base/callback.h"
+#include "base/file_util_proxy.h"
+#include "base/platform_file.h"
+#include "webkit/chromeos/fileapi/async_file_stream.h"
+
+namespace fileapi {
+
+using base::PlatformFileError;
+
+// The implementation of this base class should override all the pure virtual
+// methods and one of the following 3 choices:
+// - Read() & Write()
+// - OpenVerifiedFile()
+// - Open()
+// Read() & Write() are the easiest to implement, but in that case
+// the FileUtilAsync implementation does not have any "opened file" entity.
+// OpenVerifiedFile() will allow to overload FileSystemAsyncFileStream, making
+// it possible to hold some handle for an open file, like PlatformFile*.
+// Open() is the same as OpenVerifiedFile(), but in its case the implementation
+// is responsible for all the checks. It is preferrable in the case of remote
+// operation when it is possible to batch several checks into one query.
+class FileUtilAsync {
+ public:
+  typedef base::FileUtilProxy::Entry DirectoryEntry;
+
+  typedef base::Callback<void(
+      PlatformFileError,
+      const base::PlatformFileInfo&)> GetFileInfoCallback;
+
+  // AsyncFileStream is reference-counted.
+  typedef base::Callback<void(
+      PlatformFileError,
+      AsyncFileStream*)> OpenCallback;
+
+  typedef std::vector<DirectoryEntry> FileList;
+
+  typedef base::Callback<void(
+      PlatformFileError,
+      const FileList&,
+      bool  // true if completed
+    )> ReadDirectoryCallback;

[kinuko, 2011/12/14 03:39:22]

nit: weird indentation

[satorux1, 2011/12/14 04:43:26]

Done.

+
+  virtual void GetFileInfo(
+      const FilePath& file_path,
+      const GetFileInfoCallback& callback) = 0;
+
+  virtual void Create(
+      const FilePath& file_path,
+      const StatusCallback& callback) = 0;
+
+  virtual void Truncate(
+      const FilePath& file_path,
+      int64 length,
+      const StatusCallback& callback) = 0;
+
+  virtual void Touch(
+      const FilePath& file_path,
+      const base::Time& last_access_time,
+      const base::Time& last_modified_time,
+      const StatusCallback& callback) = 0;
+
+  virtual void Remove(
+      const FilePath& file_path,
+      bool recursive,
+      const StatusCallback& callback) = 0;
+
+  virtual void Open(
+      const FilePath& file_path,
+      int file_flags,  // PlatformFileFlags
+      const OpenCallback& callback);
+
+  virtual void CreateDirectory(
+      const FilePath& dir_path,
+      const StatusCallback& callback) = 0;
+
+  // The ReadDirectoryCallback may be called several times, returning the
+  // portions of the whole directory listing. The reference to vector with
+  // DirectoryEntry objects, passed to callback is guaranteed to contain the
+  // reults of the operation only while callback is running.
+  //
+  // The implementations of FileUtilAsync should be careful to populate the
+  // vector on the same thread, on which the callback is called. Otherwise,
+  // if callback is called through PostTask, the data might get overwritten
+  // before callback is actually called.
+  //
+  // TODO(olege): Maybe make it possible to read only a part of the directory.
+  virtual void ReadDirectory(
+      const FilePath& dir_path,
+      const ReadDirectoryCallback& callback) = 0;
+
+  // TODO(olege): Add LocalCopy and LocalMove.
+
+ protected:
+  FileUtilAsync();
+
+  virtual void Write(
+      const FilePath& file_path,
+      int64 offset,
+      const char* data,
+      int64 length,
+      const ReadWriteCallback& callback) {
+    NOTREACHED();
+  }
+
+  virtual void Read(
+      const FilePath& file_path,
+      int64 offset,
+      char* buffer,
+      int64 length,
+      const ReadWriteCallback& callback) {
+    NOTREACHED();
+  }
+
+  virtual void OpenVerifiedFile(
+      const FilePath& file_path,
+      int flags,
+      const OpenCallback& callback);
+
+ private:
+  friend class FileUtilAsyncFileStream;
+
+  void DidGetFileInfoForOpen(
+      const FilePath& file_path,
+      int flags,
+      const OpenCallback& callback,
+      PlatformFileError get_info_res,
+      const base::PlatformFileInfo& file_info);
+
+  void OpenTruncatedFileOrCreate(
+      const FilePath& file_path,
+      int flags,
+      const OpenCallback& callback,
+      PlatformFileError res);
+
+  void DidCreateOrTruncateForOpen(
+      const FilePath& file_path,
+      int flags,
+      int64 size,
+      const OpenCallback& callback,
+      PlatformFileError res);
+
+  void ReturnOpenError(PlatformFileError error,
+                       const OpenCallback& callback);
+
+  DISALLOW_COPY_AND_ASSIGN(FileUtilAsync);
+};
+
+}
+
+#endif  // WEBKIT_FILEAPI_FILE_SYSTEM_FILE_UTIL_ASYNC_H_