Add function to document_loader to get PDF as pp::FileRef

pdf/file_writer.h

+// Copyright 2014 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 PDF_FILE_WRITER_H_
+#define PDF_FILE_WRITER_H_
+
+#include <string>
+
+#include "base/basictypes.h"
+#include "base/memory/scoped_ptr.h"
+#include "ppapi/cpp/file_io.h"
+#include "ppapi/cpp/file_ref.h"
+#include "ppapi/cpp/file_system.h"
+#include "ppapi/cpp/instance_handle.h"
+#include "ppapi/utility/completion_callback_factory.h"
+
+namespace chrome_pdf {
+
+class FileWriter {
+ public:
+  FileWriter(const pp::InstanceHandle& instance,
+             const std::string& filename,
+             const char* bytes,
+             size_t length);
+
+  void GetFile(pp::CompletionCallbackWithOutput<pp::FileRef> callback);
+
+ private:
+  void OnFileSystemOpen(int32_t result);
+  void OnWriteComplete(int32_t result);
+  void OnFlushComplete(int32_t result);
+
+  pp::InstanceHandle instance_;
+  std::string filename_;
+  const char* bytes_;
+  size_t length_;
+  scoped_ptr<pp::CompletionCallbackWithOutput<pp::FileRef> > callback_;
+
+  bool succeeded_;
+  size_t offset_;
+  pp::FileRef file_ref_;
+  pp::FileSystem fs_;
+  pp::FileIO io_;
+  pp::CompletionCallbackFactory<FileWriter> callback_factory_;
+};
+
+}  // namespace chrome_pdf
+
+#endif  // PDF_FILE_WRITER_H_