Refactoring of SessionService to get componentized.

chrome/browser/sessions/base_session_service_commands.cc

+// 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.
+
+#include "chrome/browser/sessions/base_session_service_commands.h"
+
+#include "base/pickle.h"
+#include "chrome/browser/sessions/session_backend.h"
+#include "chrome/browser/sessions/session_types.h"
+
+namespace BaseSessionServiceCommands {
+
+namespace {
+
+// Helper used by CreateUpdateTabNavigationCommand(). It writes |str| to
+// |pickle|, if and only if |str| fits within (|max_bytes| - |*bytes_written|).
+// |bytes_written| is incremented to reflect the data written.
+void WriteStringToPickle(Pickle& pickle, int* bytes_written, int max_bytes,
+                         const std::string& str) {
+  int num_bytes = str.size() * sizeof(char);
+  if (*bytes_written + num_bytes < max_bytes) {
+    *bytes_written += num_bytes;
+    pickle.WriteString(str);
+  } else {
+    pickle.WriteString(std::string());
+  }
+}
+
+}  // namespace
+
+scoped_ptr<SessionCommand> CreateUpdateTabNavigationCommand(
+    SessionID::id_type command_id,
+    SessionID::id_type tab_id,
+    const sessions::SerializedNavigationEntry& navigation) {
+  // Use pickle to handle marshalling.
+  Pickle pickle;
+  pickle.WriteInt(tab_id);
+  // We only allow navigations up to 63k (which should be completely
+  // reasonable).
+  static const size_t max_state_size =
+      std::numeric_limits<SessionCommand::size_type>::max() - 1024;
+  navigation.WriteToPickle(max_state_size, &pickle);
+  return scoped_ptr<SessionCommand>(new SessionCommand(command_id, pickle));
+}
+
+scoped_ptr<SessionCommand> CreateSetTabExtensionAppIDCommand(
+    SessionID::id_type command_id,
+    SessionID::id_type tab_id,
+    const std::string& extension_id) {
+  // Use pickle to handle marshalling.
+  Pickle pickle;
+  pickle.WriteInt(tab_id);
+
+  // Enforce a max for ids. They should never be anywhere near this size.
+  static const SessionCommand::size_type max_id_size =
+      std::numeric_limits<SessionCommand::size_type>::max() - 1024;
+
+  int bytes_written = 0;
+
+  WriteStringToPickle(pickle, &bytes_written, max_id_size, extension_id);
+
+  return scoped_ptr<SessionCommand>(new SessionCommand(command_id, pickle));
+}
+
+scoped_ptr<SessionCommand> CreateSetTabUserAgentOverrideCommand(
+    SessionID::id_type command_id,
+    SessionID::id_type tab_id,
+    const std::string& user_agent_override) {
+  // Use pickle to handle marshalling.
+  Pickle pickle;
+  pickle.WriteInt(tab_id);
+
+  // Enforce a max for the user agent length.  They should never be anywhere
+  // near this size.
+  static const SessionCommand::size_type max_user_agent_size =
+      std::numeric_limits<SessionCommand::size_type>::max() - 1024;
+
+  int bytes_written = 0;
+
+  WriteStringToPickle(pickle, &bytes_written, max_user_agent_size,
+      user_agent_override);
+
+  return scoped_ptr<SessionCommand>(new SessionCommand(command_id, pickle));
+}
+
+scoped_ptr<SessionCommand> CreateSetWindowAppNameCommand(
+    SessionID::id_type command_id,
+    SessionID::id_type window_id,
+    const std::string& app_name) {
+  // Use pickle to handle marshalling.
+  Pickle pickle;
+  pickle.WriteInt(window_id);
+
+  // Enforce a max for ids. They should never be anywhere near this size.
+  static const SessionCommand::size_type max_id_size =
+      std::numeric_limits<SessionCommand::size_type>::max() - 1024;
+
+  int bytes_written = 0;
+
+  WriteStringToPickle(pickle, &bytes_written, max_id_size, app_name);
+
+  return scoped_ptr<SessionCommand>(new SessionCommand(command_id, pickle));
+}
+
+bool RestoreUpdateTabNavigationCommand(
+    const SessionCommand& command,
+    sessions::SerializedNavigationEntry* navigation,
+    SessionID::id_type* tab_id) {
+  scoped_ptr<Pickle> pickle(command.PayloadAsPickle());
+  if (!pickle.get())
+    return false;
+  PickleIterator iterator(*pickle);
+  return pickle->ReadInt(&iterator, tab_id) &&
+         navigation->ReadFromPickle(&iterator);
+}
+
+bool RestoreSetTabExtensionAppIDCommand(const SessionCommand& command,
+                                        SessionID::id_type* tab_id,
+                                        std::string* extension_app_id) {
+  scoped_ptr<Pickle> pickle(command.PayloadAsPickle());
+  if (!pickle.get())
+    return false;
+
+  PickleIterator iterator(*pickle);
+  return pickle->ReadInt(&iterator, tab_id) &&
+      pickle->ReadString(&iterator, extension_app_id);
+}
+
+bool RestoreSetTabUserAgentOverrideCommand(const SessionCommand& command,
+                                           SessionID::id_type* tab_id,
+                                           std::string* user_agent_override) {
+  scoped_ptr<Pickle> pickle(command.PayloadAsPickle());
+  if (!pickle.get())
+    return false;
+
+  PickleIterator iterator(*pickle);
+  return pickle->ReadInt(&iterator, tab_id) &&
+      pickle->ReadString(&iterator, user_agent_override);
+}
+
+bool RestoreSetWindowAppNameCommand(const SessionCommand& command,
+                                    SessionID::id_type* window_id,
+                                    std::string* app_name) {
+  scoped_ptr<Pickle> pickle(command.PayloadAsPickle());
+  if (!pickle.get())
+    return false;
+
+  PickleIterator iterator(*pickle);
+  return pickle->ReadInt(&iterator, window_id) &&
+      pickle->ReadString(&iterator, app_name);
+}
+
+}  // namespace BaseSessionServiceCommands