Simple PMP reader to parse Picasa's metadata

webkit/fileapi/media/picasa/pmp_table_reader.h

+// Copyright 2013 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_MEDIA_PICASA_PMP_TABLE_READER_H_
+#define WEBKIT_FILEAPI_MEDIA_PICASA_PMP_TABLE_READER_H_
+
+#include <string>
+
+#include "base/basictypes.h"
+#include "base/memory/scoped_vector.h"
+
+namespace base {
+class FilePath;
+}
+
+namespace fileapi {
+
+class PmpColumnReader;
+
+class PmpTableReader {
+ public:
+  PmpTableReader(const std::string& table_name,
+                 const base::FilePath& directory_path,
+                 const std::vector<std::string>& columns);
+
+  virtual ~PmpTableReader();
+
+  // |columns| parameter will define, in-order, the columns returned by
+  // subsequent columns to GetColumns() if ReadFromDisk() succeeds.
+  // Warning: Invalidates previously obtained pointers from GetColumns().

[vandebo (ex-Chrome), 2013/03/28 00:56:04]

It seems that this class doesn't need to be reuseable.  Is there any reason to
call ReadFromDisk again?  Is the only purpose to be able to give an error?  How
about making this an Init method, putting everything from the constructor here,
and returning failure if multiple attempts to init are made?

[tommycli, 2013/03/29 00:16:01]

Done.

+  bool ReadFromDisk();
+
+  // Returns a const "view" of the current contents of |column_readers_|.
+  // Warning: Calling ReadFromDisk() will invalidate pointers returned here.
+  std::vector<const PmpColumnReader*> GetColumns() const;
+
+  uint32 RowCount() const;
+
+ private:
+  const std::string& table_name_;
+  const base::FilePath& directory_path_;
+  const std::vector<std::string>& columns_;
+
+  // Contains the last 'good' read of the disk.
+  ScopedVector<PmpColumnReader> column_readers_;
+  // Contains the number of rows obtained during the last 'good' read of disk.
+  uint32 max_row_count_;
+
+  DISALLOW_COPY_AND_ASSIGN(PmpTableReader);
+};
+
+}  // namespace fileapi
+
+#endif  // WEBKIT_FILEAPI_MEDIA_PICASA_PMP_TABLE_READER_H_