4 /* Copyright 2002 The gtkmm Development Team
6 * This library is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Library General Public
8 * License as published by the Free Software Foundation; either
9 * version 2 of the License, or (at your option) any later version.
11 * This library is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Library General Public License for more details.
16 * You should have received a copy of the GNU Library General Public
17 * License along with this library; if not, write to the Free
18 * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
21 #include <glib-object.h>
23 #include <glibmm/quark.h>
24 #include <glibmm/objectbase.h>
30 // Used by the Glib::ObjectBase default ctor. Using an explicitly defined
31 // char array rather than a string literal allows for fast pointer comparison,
32 // which is otherwise not guaranteed to work.
34 const char anonymous_custom_type_name[] = "gtkmm__anonymous_custom_type";
36 } // anonymous namespace
42 /**** Glib::ObjectBase *****************************************************/
44 ObjectBase::ObjectBase()
47 custom_type_name_ (anonymous_custom_type_name),
48 cpp_destruction_in_progress_ (false)
51 ObjectBase::ObjectBase(const char* custom_type_name)
54 custom_type_name_ (custom_type_name),
55 cpp_destruction_in_progress_ (false)
58 ObjectBase::ObjectBase(const std::type_info& custom_type_info)
61 custom_type_name_ (custom_type_info.name()),
62 cpp_destruction_in_progress_ (false)
65 // initialize() actually initializes the wrapper. Glib::ObjectBase is used
66 // as virtual base class, which means the most-derived class' ctor invokes
67 // the Glib::ObjectBase ctor -- thus it's useless for Glib::Object.
69 void ObjectBase::initialize(GObject* castitem)
73 // initialize() might be called twice when used with MI, e.g. by the ctors
74 // of Glib::Object and Glib::Interface. However, they must both refer to
75 // the same underlying GObject instance.
77 g_assert(gobject_ == castitem);
79 // TODO: Think about it. Will this really be called twice?
80 g_printerr("ObjectBase::initialize() called twice for the same GObject\n");
82 return; // Don't initialize the wrapper twice.
85 //g_print("%s : %s\n", G_GNUC_PRETTY_FUNCTION, G_OBJECT_TYPE_NAME(castitem));
88 _set_current_wrapper(castitem);
91 ObjectBase::~ObjectBase()
93 // Normally, gobject_ should always be 0 at this point, because:
95 // a) Gtk::Object handles memory management on its own and always resets
96 // the gobject_ pointer in its destructor.
98 // b) Glib::Object instances that aren't Gtk::Objects will always be
99 // deleted by the destroy_notify_() virtual method. Calling delete
100 // on a Glib::Object is a programming error.
102 // The *only* situation where gobject_ is validly not 0 at this point
103 // happens if a derived class's ctor throws an exception. In that case
104 // we have to call g_object_unref() on our own.
106 if(GObject *const gobject = gobject_)
108 #ifdef GLIBMM_DEBUG_REFCOUNTING
109 g_warning("(Glib::ObjectBase::~ObjectBase): gobject_ = %p", (void*) gobject_);
114 #ifdef GLIBMM_DEBUG_REFCOUNTING
115 g_warning("(Glib::ObjectBase::~ObjectBase): before g_object_steal_qdata()");
118 // Remove the pointer to the wrapper from the underlying instance.
119 // This does _not_ cause invocation of the destroy_notify callback.
120 g_object_steal_qdata(gobject, quark_);
122 #ifdef GLIBMM_DEBUG_REFCOUNTING
123 g_warning("(Glib::ObjectBase::~ObjectBase): calling g_object_unref()");
126 g_object_unref(gobject);
130 void ObjectBase::reference() const
132 GLIBMM_DEBUG_REFERENCE(this, gobject_);
133 g_object_ref(gobject_);
136 void ObjectBase::unreference() const
138 GLIBMM_DEBUG_UNREFERENCE(this, gobject_);
139 g_object_unref(gobject_);
142 GObject* ObjectBase::gobj_copy() const
148 void ObjectBase::_set_current_wrapper(GObject* object)
150 // Store a pointer to this wrapper in the underlying instance, so that we
151 // never create a second wrapper for the same underlying instance. Also,
152 // specify a callback that will tell us when it's time to delete this C++
157 if(!g_object_get_qdata(object, Glib::quark_))
159 g_object_set_qdata_full(object, Glib::quark_, this, &destroy_notify_callback_);
163 g_warning("This object, of type %s, already has a wrapper.\n"
164 "You should use wrap() instead of a constructor.",
165 G_OBJECT_TYPE_NAME(object));
171 ObjectBase* ObjectBase::_get_current_wrapper(GObject* object)
174 return static_cast<ObjectBase*>(g_object_get_qdata(object, Glib::quark_));
180 void ObjectBase::destroy_notify_callback_(void* data)
184 // This method is called (indirectly) from g_object_run_dispose().
185 // Get the C++ instance associated with the C instance:
186 ObjectBase* cppObject = static_cast<ObjectBase*>(data); //Previously set with g_object_set_qdata_full().
188 #ifdef GLIBMM_DEBUG_REFCOUNTING
189 g_warning("ObjectBase::destroy_notify_callback_: cppObject = %p, gobject_ = %p, gtypename = %s",
190 (void*) cppObject, (void*) cppObject->gobject_, cppObject->gobject_);
193 if(cppObject) //This will be 0 if the C++ destructor has already run.
195 cppObject->destroy_notify_(); //Virtual - it does different things for GObject and GtkObject.
199 void ObjectBase::destroy_notify_()
201 // The C instance is about to be disposed, making it unusable. Now is a
202 // good time to delete the C++ wrapper of the C instance. There is no way
203 // to force the disposal of the GObject (though GtkObject has
204 // gtk_object_destroy()), So this is the *only* place where we delete the
207 // This will only happen after the last unreference(), which will be done by
208 // the RefPtr<> destructor. There should be no way to access the wrapper or
209 // the undobjecterlying instance after that, so it's OK to delete this.
211 #ifdef GLIBMM_DEBUG_REFCOUNTING
212 g_warning("Glib::ObjectBase::destroy_notify_: gobject_ = %p", (void*) gobject_);
215 gobject_ = 0; // Make sure we don't unref it again in the dtor.
220 bool ObjectBase::is_anonymous_custom_() const
222 // Doing high-speed pointer comparison is OK here.
223 return (custom_type_name_ == anonymous_custom_type_name);
226 bool ObjectBase::is_derived_() const
228 // gtkmmproc-generated classes initialize this to 0 by default.
229 return (custom_type_name_ != 0);
232 void ObjectBase::set_manage()
234 // This is a private method and Gtk::manage() is a template function.
235 // Thus this will probably never run, unless you do something like:
237 // manage(static_cast<Gtk::Object*>(refptr.operator->()));
239 g_error("Glib::ObjectBase::set_manage(): "
240 "only Gtk::Object instances can be managed");
243 bool ObjectBase::_cpp_destruction_is_in_progress() const
245 return cpp_destruction_in_progress_;
248 void ObjectBase::set_property_value(const Glib::ustring& property_name, const Glib::ValueBase& value)
250 g_object_set_property(gobj(), property_name.c_str(), value.gobj());
253 void ObjectBase::get_property_value(const Glib::ustring& property_name, Glib::ValueBase& value) const
255 g_object_get_property(const_cast<GObject*>(gobj()), property_name.c_str(), value.gobj());
259 bool _gobject_cppinstance_already_deleted(GObject* gobject)
261 //This function is used to prevent calling wrap() on a GTK+ instance whose gtkmm instance has been deleted.
264 return (bool)g_object_get_qdata(gobject, Glib::quark_cpp_wrapper_deleted_); //true means that something is odd.
266 return false; //Nothing is particularly wrong.