// -*- c++ -*- /* $Id: objectbase.cc 530 2008-01-20 18:54:44Z murrayc $ */ /* Copyright 2002 The gtkmm Development Team * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Library General Public * License as published by the Free Software Foundation; either * version 2 of the License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Library General Public License for more details. * * You should have received a copy of the GNU Library General Public * License along with this library; if not, write to the Free * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ #include #include #include #include //For PropertyProxyConnectionNode namespace { // Used by the Glib::ObjectBase default ctor. Using an explicitly defined // char array rather than a string literal allows for fast pointer comparison, // which is otherwise not guaranteed to work. static const char anonymous_custom_type_name[] = "gtkmm__anonymous_custom_type"; } // anonymous namespace namespace Glib { /**** Glib::ObjectBase *****************************************************/ ObjectBase::ObjectBase() : gobject_ (0), custom_type_name_ (anonymous_custom_type_name), cpp_destruction_in_progress_ (false) {} ObjectBase::ObjectBase(const char* custom_type_name) : gobject_ (0), custom_type_name_ (custom_type_name), cpp_destruction_in_progress_ (false) {} ObjectBase::ObjectBase(const std::type_info& custom_type_info) : gobject_ (0), custom_type_name_ (custom_type_info.name()), cpp_destruction_in_progress_ (false) {} // initialize() actually initializes the wrapper. Glib::ObjectBase is used // as virtual base class, which means the most-derived class' ctor invokes // the Glib::ObjectBase ctor -- thus it's useless for Glib::Object. // void ObjectBase::initialize(GObject* castitem) { if(gobject_) { // initialize() might be called twice when used with MI, e.g. by the ctors // of Glib::Object and Glib::Interface. However, they must both refer to // the same underlying GObject instance. // g_assert(gobject_ == castitem); // TODO: Think about it. Will this really be called twice? g_printerr("ObjectBase::initialize() called twice for the same GObject\n"); return; // Don't initialize the wrapper twice. } //g_print("%s : %s\n", G_GNUC_PRETTY_FUNCTION, G_OBJECT_TYPE_NAME(castitem)); gobject_ = castitem; _set_current_wrapper(castitem); } ObjectBase::~ObjectBase() { // Normally, gobject_ should always be 0 at this point, because: // // a) Gtk::Object handles memory management on its own and always resets // the gobject_ pointer in its destructor. // // b) Glib::Object instances that aren't Gtk::Objects will always be // deleted by the destroy_notify_() virtual method. Calling delete // on a Glib::Object is a programming error. // // The *only* situation where gobject_ is validly not 0 at this point // happens if a derived class's ctor throws an exception. In that case // we have to call g_object_unref() on our own. // if(GObject *const gobject = gobject_) { #ifdef GLIBMM_DEBUG_REFCOUNTING g_warning("(Glib::ObjectBase::~ObjectBase): gobject_ = %p", (void*) gobject_); #endif gobject_ = 0; #ifdef GLIBMM_DEBUG_REFCOUNTING g_warning("(Glib::ObjectBase::~ObjectBase): before g_object_steal_qdata()"); #endif // Remove the pointer to the wrapper from the underlying instance. // This does _not_ cause invocation of the destroy_notify callback. g_object_steal_qdata(gobject, quark_); #ifdef GLIBMM_DEBUG_REFCOUNTING g_warning("(Glib::ObjectBase::~ObjectBase): calling g_object_unref()"); #endif g_object_unref(gobject); } } void ObjectBase::reference() const { GLIBMM_DEBUG_REFERENCE(this, gobject_); g_object_ref(gobject_); } void ObjectBase::unreference() const { GLIBMM_DEBUG_UNREFERENCE(this, gobject_); g_object_unref(gobject_); } GObject* ObjectBase::gobj_copy() const { reference(); return gobject_; } void ObjectBase::_set_current_wrapper(GObject* object) { // Store a pointer to this wrapper in the underlying instance, so that we // never create a second wrapper for the same underlying instance. Also, // specify a callback that will tell us when it's time to delete this C++ // wrapper instance: if(object) { if(!g_object_get_qdata(object, Glib::quark_)) { g_object_set_qdata_full(object, Glib::quark_, this, &destroy_notify_callback_); } else { g_warning("This object, of type %s, already has a wrapper.\n" "You should use wrap() instead of a constructor.", G_OBJECT_TYPE_NAME(object)); } } } // static ObjectBase* ObjectBase::_get_current_wrapper(GObject* object) { if(object) return static_cast(g_object_get_qdata(object, Glib::quark_)); else return 0; } // static void ObjectBase::destroy_notify_callback_(void* data) { //GLIBMM_LIFECYCLE // This method is called (indirectly) from g_object_run_dispose(). // Get the C++ instance associated with the C instance: ObjectBase* cppObject = static_cast(data); //Previously set with g_object_set_qdata_full(). #ifdef GLIBMM_DEBUG_REFCOUNTING g_warning("ObjectBase::destroy_notify_callback_: cppObject = %p, gobject_ = %p, gtypename = %s", (void*) cppObject, (void*) cppObject->gobject_, cppObject->gobject_); #endif if(cppObject) //This will be 0 if the C++ destructor has already run. { cppObject->destroy_notify_(); //Virtual - it does different things for GObject and GtkObject. } } void ObjectBase::destroy_notify_() { // The C instance is about to be disposed, making it unusable. Now is a // good time to delete the C++ wrapper of the C instance. There is no way // to force the disposal of the GObject (though GtkObject has // gtk_object_destroy()), So this is the *only* place where we delete the // C++ wrapper. // // This will only happen after the last unreference(), which will be done by // the RefPtr<> destructor. There should be no way to access the wrapper or // the undobjecterlying instance after that, so it's OK to delete this. #ifdef GLIBMM_DEBUG_REFCOUNTING g_warning("Glib::ObjectBase::destroy_notify_: gobject_ = %p", (void*) gobject_); #endif gobject_ = 0; // Make sure we don't unref it again in the dtor. delete this; } bool ObjectBase::is_anonymous_custom_() const { // Doing high-speed pointer comparison is OK here. return (custom_type_name_ == anonymous_custom_type_name); } bool ObjectBase::is_derived_() const { // gtkmmproc-generated classes initialize this to 0 by default. return (custom_type_name_ != 0); } void ObjectBase::set_manage() { // This is a private method and Gtk::manage() is a template function. // Thus this will probably never run, unless you do something like: // // manage(static_cast(refptr.operator->())); g_error("Glib::ObjectBase::set_manage(): " "only Gtk::Object instances can be managed"); } bool ObjectBase::_cpp_destruction_is_in_progress() const { return cpp_destruction_in_progress_; } void ObjectBase::set_property_value(const Glib::ustring& property_name, const Glib::ValueBase& value) { g_object_set_property(gobj(), property_name.c_str(), value.gobj()); } void ObjectBase::get_property_value(const Glib::ustring& property_name, Glib::ValueBase& value) const { g_object_get_property(const_cast(gobj()), property_name.c_str(), value.gobj()); } void ObjectBase::connect_property_changed(const Glib::ustring& property_name, const sigc::slot& slot) { connect_property_changed_with_return(property_name, slot); } sigc::connection ObjectBase::connect_property_changed_with_return(const Glib::ustring& property_name, const sigc::slot& slot) { // Create a proxy to hold our connection info // This will be deleted by destroy_notify_handler. PropertyProxyConnectionNode* pConnectionNode = new PropertyProxyConnectionNode(slot, gobj()); // connect it to gtk+ // pConnectionNode will be passed as the data argument to the callback. // The callback will then call the virtual Object::property_change_notify() method, // which will contain a switch/case statement which will examine the property name. const Glib::ustring notify_signal_name = "notify::" + property_name; pConnectionNode->connection_id_ = g_signal_connect_data(gobj(), notify_signal_name.c_str(), (GCallback)(&PropertyProxyConnectionNode::callback), pConnectionNode, &PropertyProxyConnectionNode::destroy_notify_handler, G_CONNECT_AFTER); return sigc::connection(pConnectionNode->slot_); } bool _gobject_cppinstance_already_deleted(GObject* gobject) { //This function is used to prevent calling wrap() on a GTK+ instance whose gtkmm instance has been deleted. if(gobject) return (bool)g_object_get_qdata(gobject, Glib::quark_cpp_wrapper_deleted_); //true means that something is odd. else return false; //Nothing is particularly wrong. } } // namespace Glib