[fsp] Extract common code to FileSystemProvidedInternalFunction.

chrome/browser/chromeos/extensions/file_system_provider/provider_function.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 CHROME_BROWSER_CHROMEOS_EXTENSIONS_FILE_SYSTEM_PROVIDER_PROVIDER_FUNCTION_H_
+#define CHROME_BROWSER_CHROMEOS_EXTENSIONS_FILE_SYSTEM_PROVIDER_PROVIDER_FUNCTION_H_
+#include <string>
+
+#include "base/files/file.h"
+#include "base/memory/scoped_ptr.h"
+#include "chrome/browser/extensions/chrome_extension_function.h"
+#include "chrome/common/extensions/api/file_system_provider.h"
+
+namespace base {
+class DictionaryValue;
+}  // namespace base
+
+namespace chromeos {
+namespace file_system_provider {
+
+class RequestManager;
+class RequestValue;
+
+}  // namespace file_system_provider
+}  // namespace chromeos
+
+namespace extensions {
+
+// Error names from
+// http://www.w3.org/TR/file-system-api/#errors-and-exceptions
+extern const char kNotFoundErrorName[];
+extern const char kSecurityErrorName[];
+
+// Error messages.
+extern const char kEmptyNameErrorMessage[];
+extern const char kMountFailedErrorMessage[];
+extern const char kUnmountFailedErrorMessage[];
+extern const char kResponseFailedErrorMessage[];
+
+// Creates a dictionary, which looks like a DOMError. The returned dictionary
+// will be converted to a real DOMError object in
+// file_system_provier_custom_bindings.js.
+base::DictionaryValue* CreateError(const std::string& name,
+                                   const std::string& message);
+
+// Converts ProviderError to base::File::Error. This could be redundant, if it
+// was possible to create DOMError instances in Javascript easily.
+base::File::Error ProviderErrorToFileError(
+    api::file_system_provider::ProviderError error);
+
+// Base class for internal API functions handling request results, either
+// a success or a failure.
+class FileSystemProviderInternalFunction : public ChromeSyncExtensionFunction {
+ public:
+  FileSystemProviderInternalFunction();
+
+ protected:
+  virtual ~FileSystemProviderInternalFunction() {}
+
+  // Rejects the request and sets a response for this API function.
+  void RejectRequest(base::File::Error error);
+
+  // Fulfills the request with parsed arguments of this API function
+  // encapsulated as a RequestValue instance. Also, sets a response.
+  // If |has_next| is set to true, then the function will be called again for
+  // this request.
+  void FulfillRequest(
+      scoped_ptr<chromeos::file_system_provider::RequestValue> value,
+      bool has_next);
+
+  // ChromeSyncExtensionFunction overrides.
+  virtual bool RunImpl() OVERRIDE;
+
+ private:
+  // Parses the request in order to extract the request manager. If fails, then
+  // sets a response and returns false.
+  bool Parse();
+
+  // Sets an error message in case of a failure.
+  void SetErrorResponse(const std::string& name, const std::string& message);
+
+  int request_id_;
+  chromeos::file_system_provider::RequestManager* request_manager_;
+};
+
+}  // namespace extensions
+
+#endif  // CHROME_BROWSER_CHROMEOS_EXTENSIONS_FILE_SYSTEM_PROVIDER_PROVIDER_FUNCTION_H_