Implement Bus and ObjectProxy classes for our D-Bus library.

dbus/exported_object.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 DBUS_EXPORTED_OBJECT_H_
+#define DBUS_EXPORTED_OBJECT_H_
+#pragma once
+
+#include <string>
+#include <map>
+#include <utility>
+
+#include <dbus/dbus.h>
+
+#include "base/callback.h"
+#include "base/memory/ref_counted.h"
+#include "base/synchronization/condition_variable.h"
+#include "base/threading/platform_thread.h"
+
+class MessageLoop;
+
+namespace dbus {
+
+class Bus;
+class MethodCall;
+class Response;
+
+// ExportedObject is used to export objects and methods to other D-Bus
+// clients.
+//
+// ExportedObject is a ref counted object, to ensure that |this| of the
+// object is alive when callbacks referencing |this| are called.
+class ExportedObject : public base::RefCountedThreadSafe<ExportedObject> {
+ public:
+  // Client code should use Bus::GetExportedObject() instead of this
+  // constructor.
+  ExportedObject(Bus* bus,
+                 const std::string& service_name,
+                 const std::string& object_path);
+
+  // Called when an exported method is called. MethodCall* is the request
+  // message.
+  typedef base::Callback<Response* (MethodCall*)> MethodCallCallback;
+
+  // Called when method exporting is done.
+  // Parameters:
+  // - the interface name.
+  // - the method name.
+  // - whether exporting was successful or not.
+  typedef base::Callback<void (const std::string&, const std::string&, bool)>
+      OnExportedCallback;
+
+  // Exports the method specified by |interface_name| and |method_name|,
+  // and blocks until exporting is done. Returns true on success.
+  //
+  // |method_call_callback| will be called in the origin thread, when the
+  // exported method is called. As it's called in the origin thread,
+  // callback| can safely reference objects in the origin thread (i.e. UI
+  // thread in most cases).
+  //
+  // BLOCKING CALL.
+  virtual bool ExportMethodAndBlock(const std::string& interface_name,
+                                    const std::string& method_name,
+                                    MethodCallCallback method_call_callback);
+
+  // Requests to export the method specified by |interface_name| and
+  // |method_name|. See Also ExportMethodAndBlock().
+  //
+  // |on_exported_callback| is called when the method is exported or
+  // failed to be exported, in the origin thread.
+  //
+  // Must be called in the origin thread.
+  virtual void ExportMethod(const std::string& interface_name,
+                            const std::string& method_name,
+                            MethodCallCallback method_call_callback,
+                            OnExportedCallback on_exported_callback);
+
+  // Unregisters the object from the bus. The Bus object will take care of
+  // unregistering so you don't have to do this manually.
+  //
+  // BLOCKING CALL.
+  virtual void Unregister();
+
+ private:
+  friend class base::RefCountedThreadSafe<ExportedObject>;
+  virtual ~ExportedObject();
+
+  // Helper function for ExportMethod().
+  void ExportMethodInternal(const std::string& interface_name,
+                            const std::string& method_name,
+                            MethodCallCallback method_call_callback,
+                            OnExportedCallback exported_callback);
+
+  // Called when the object is exported.
+  void OnExported(OnExportedCallback on_exported_callback,
+                  const std::string& interface_name,
+                  const std::string& method_name,
+                  bool success);
+
+  // Registers this object to the bus.
+  // Returns true on success, or the object is already registered.
+  //
+  // BLOCKING CALL.
+  bool Register();
+
+  // Handles the incoming request messages and dispatches to the exported
+  // methods.
+  DBusHandlerResult HandleMessage(DBusConnection* connection,
+                                  DBusMessage* raw_message);
+
+  // Runs the method. Helper function for HandleMessage().
+  void RunMethod(MethodCallCallback method_call_callback,
+                 MethodCall* method_call);
+
+  // Called when the object is unregistered.
+  void OnUnregistered(DBusConnection* connection);
+
+  // Redirects the function call to HandleMessage().
+  static DBusHandlerResult HandleMessageThunk(DBusConnection* connection,
+                                              DBusMessage* raw_message,
+                                              void* user_data);
+
+  // Redirects the function call to OnUnregistered().
+  static void OnUnregisteredThunk(DBusConnection* connection,
+                                  void* user_data);
+
+  Bus* bus_;
+  std::string service_name_;
+  std::string object_path_;
+  bool object_is_registered_;
+  bool method_is_called_;
+  dbus::Response* response_from_method_;
+  base::Lock method_is_called_lock_;
+  base::ConditionVariable on_method_is_called_;
+
+  // The method table where keys are absolute method names (i.e. interface
+  // name + method name), and values are the corresponding callbacks.
+  typedef std::map<std::string, MethodCallCallback> MethodTable;
+  MethodTable method_table_;
+};
+
+}  // namespace dbus
+
+#endif  // DBUS_EXPORTED_OBJECT_H_