gi/pygpointer.c

   1 /* -*- Mode: C; c-basic-offset: 4 -*-
   2  * pygtk- Python bindings for the GTK toolkit.
   3  * Copyright (C) 1998-2003  James Henstridge
   4  *
   5  *   pygpointer.c: wrapper for GPointer
   6  *
   7  * This library is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * This library is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
  19  */
  20
  21 #ifdef HAVE_CONFIG_H
  22 #  include <config.h>
  23 #endif
  24
  25 #include <pyglib.h>
  26 #include "pygobject-private.h"
  27 #include "pygpointer.h"
  28
  29 #include "pygi-type.h"
  30
  31
  32 GQuark pygpointer_class_key;
  33
  34 PYGLIB_DEFINE_TYPE("gobject.GPointer", PyGPointer_Type, PyGPointer);
  35
  36 static void
  37 pyg_pointer_dealloc(PyGPointer *self)
  38 {
  39     Py_TYPE(self)->tp_free((PyObject *)self);
  40 }
  41
  42 static PyObject*
  43 pyg_pointer_richcompare(PyObject *self, PyObject *other, int op)
  44 {
  45     if (Py_TYPE(self) == Py_TYPE(other))
  46         return _pyglib_generic_ptr_richcompare (pyg_pointer_get_ptr (self),
  47                                                 pyg_pointer_get_ptr (other),
  48                                                 op);
  49     else {
  50         Py_INCREF(Py_NotImplemented);
  51         return Py_NotImplemented;
  52     }
  53 }
  54
  55 static long
  56 pyg_pointer_hash(PyGPointer *self)
  57 {
  58     return (long)pyg_pointer_get_ptr (self);
  59 }
  60
  61 static PyObject *
  62 pyg_pointer_repr(PyGPointer *self)
  63 {
  64     gchar buf[128];
  65
  66     g_snprintf(buf, sizeof(buf), "<%s at 0x%lx>", g_type_name(self->gtype),
  67                (long)pyg_pointer_get_ptr (self));
  68     return PYGLIB_PyUnicode_FromString(buf);
  69 }
  70
  71 static int
  72 pyg_pointer_init(PyGPointer *self, PyObject *args, PyObject *kwargs)
  73 {
  74     gchar buf[512];
  75
  76     if (!PyArg_ParseTuple(args, ":GPointer.__init__"))
  77         return -1;
  78
  79     pyg_pointer_set_ptr (self, NULL);
  80     self->gtype = 0;
  81
  82     g_snprintf(buf, sizeof(buf), "%s can not be constructed",
  83                Py_TYPE(self)->tp_name);
  84     PyErr_SetString(PyExc_NotImplementedError, buf);
  85     return -1;
  86 }
  87
  88 static void
  89 pyg_pointer_free(PyObject *op)
  90 {
  91   PyObject_FREE(op);
  92 }
  93
  94 /**
  95  * pyg_register_pointer:
  96  * @dict: the module dictionary to store the wrapper class.
  97  * @class_name: the Python name for the wrapper class.
  98  * @pointer_type: the GType of the pointer type being wrapped.
  99  * @type: the wrapper class.
 100  *
 101  * Registers a wrapper for a pointer type.  The wrapper class will be
 102  * a subclass of gobject.GPointer, and a reference to the wrapper
 103  * class will be stored in the provided module dictionary.
 104  */
 105 void
 106 pyg_register_pointer(PyObject *dict, const gchar *class_name,
 107                      GType pointer_type, PyTypeObject *type)
 108 {
 109     PyObject *o;
 110
 111     g_return_if_fail(dict != NULL);
 112     g_return_if_fail(class_name != NULL);
 113     g_return_if_fail(pointer_type != 0);
 114
 115     if (!type->tp_dealloc) type->tp_dealloc = (destructor)pyg_pointer_dealloc;
 116
 117     Py_TYPE(type) = &PyType_Type;
 118     type->tp_base = &PyGPointer_Type;
 119
 120     if (PyType_Ready(type) < 0) {
 121         g_warning("could not get type `%s' ready", type->tp_name);
 122         return;
 123     }
 124
 125     PyDict_SetItemString(type->tp_dict, "__gtype__",
 126                          o=pyg_type_wrapper_new(pointer_type));
 127     Py_DECREF(o);
 128
 129     g_type_set_qdata(pointer_type, pygpointer_class_key, type);
 130
 131     PyDict_SetItemString(dict, (char *)class_name, (PyObject *)type);
 132 }
 133
 134 /**
 135  * pyg_pointer_new:
 136  * @pointer_type: the GType of the pointer value.
 137  * @pointer: the pointer value.
 138  *
 139  * Creates a wrapper for a pointer value.  Since G_TYPE_POINTER types
 140  * don't register any information about how to copy/free them, there
 141  * is no guarantee that the pointer will remain valid, and there is
 142  * nothing registered to release the pointer when the pointer goes out
 143  * of scope.  This is why we don't recommend people use these types.
 144  *
 145  * Returns: the boxed wrapper.
 146  */
 147 PyObject *
 148 pyg_pointer_new(GType pointer_type, gpointer pointer)
 149 {
 150     PyGILState_STATE state;
 151     PyGPointer *self;
 152     PyTypeObject *tp;
 153     g_return_val_if_fail(pointer_type != 0, NULL);
 154
 155     state = pyglib_gil_state_ensure();
 156
 157     if (!pointer) {
 158         Py_INCREF(Py_None);
 159         pyglib_gil_state_release(state);
 160         return Py_None;
 161     }
 162
 163     tp = g_type_get_qdata(pointer_type, pygpointer_class_key);
 164
 165     if (!tp)
 166         tp = (PyTypeObject *)pygi_type_import_by_g_type(pointer_type);
 167
 168     if (!tp)
 169         tp = (PyTypeObject *)&PyGPointer_Type; /* fallback */
 170     self = PyObject_NEW(PyGPointer, tp);
 171
 172     pyglib_gil_state_release(state);
 173
 174     if (self == NULL)
 175         return NULL;
 176
 177     pyg_pointer_set_ptr (self, pointer);
 178     self->gtype = pointer_type;
 179
 180     return (PyObject *)self;
 181 }
 182
 183 void
 184 pygobject_pointer_register_types(PyObject *d)
 185 {
 186     pygpointer_class_key     = g_quark_from_static_string("PyGPointer::class");
 187
 188     PyGPointer_Type.tp_dealloc = (destructor)pyg_pointer_dealloc;
 189     PyGPointer_Type.tp_richcompare = pyg_pointer_richcompare;
 190     PyGPointer_Type.tp_repr = (reprfunc)pyg_pointer_repr;
 191     PyGPointer_Type.tp_hash = (hashfunc)pyg_pointer_hash;
 192     PyGPointer_Type.tp_flags = Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE;
 193     PyGPointer_Type.tp_init = (initproc)pyg_pointer_init;
 194     PyGPointer_Type.tp_free = (freefunc)pyg_pointer_free;
 195     PYGOBJECT_REGISTER_GTYPE(d, PyGPointer_Type, "GPointer", G_TYPE_POINTER);
 196 }