gi/pygi-struct.c

   1 /* -*- Mode: C; c-basic-offset: 4 -*-
   2  * vim: tabstop=4 shiftwidth=4 expandtab
   3  *
   4  * Copyright (C) 2009 Simon van der Linden <svdlinden@src.gnome.org>
   5  *
   6  *   pygi-struct.c: wrapper to handle non-registered structures.
   7  *
   8  * This library is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU Lesser General Public
  10  * License as published by the Free Software Foundation; either
  11  * version 2.1 of the License, or (at your option) any later version.
  12  *
  13  * This library is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  * Lesser General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU Lesser General Public
  19  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
  20  */
  21
  22 #include "pygi-struct.h"
  23 #include "pygi-foreign.h"
  24 #include "pygi-info.h"
  25 #include "pygi-type.h"
  26 #include "pygtype.h"
  27 #include "pygpointer.h"
  28
  29 #include <girepository.h>
  30 #include <pyglib-python-compat.h>
  31
  32
  33 static GIBaseInfo *
  34 _struct_get_info (PyObject *self)
  35 {
  36     PyObject *py_info;
  37     GIBaseInfo *info = NULL;
  38
  39     py_info = PyObject_GetAttrString (self, "__info__");
  40     if (py_info == NULL) {
  41         return NULL;
  42     }
  43     if (!PyObject_TypeCheck (py_info, &PyGIStructInfo_Type) &&
  44             !PyObject_TypeCheck (py_info, &PyGIUnionInfo_Type)) {
  45         PyErr_Format (PyExc_TypeError, "attribute '__info__' must be %s or %s, not %s",
  46                       PyGIStructInfo_Type.tp_name,
  47                       PyGIUnionInfo_Type.tp_name,
  48                       Py_TYPE(py_info)->tp_name);
  49         goto out;
  50     }
  51
  52     info = ( (PyGIBaseInfo *) py_info)->info;
  53     g_base_info_ref (info);
  54
  55 out:
  56     Py_DECREF (py_info);
  57
  58     return info;
  59 }
  60
  61 static void
  62 _struct_dealloc (PyGIStruct *self)
  63 {
  64     GIBaseInfo *info = _struct_get_info ( (PyObject *) self );
  65
  66     if (info != NULL && g_struct_info_is_foreign ( (GIStructInfo *) info)) {
  67         pygi_struct_foreign_release (info, pyg_pointer_get_ptr (self));
  68     } else if (self->free_on_dealloc) {
  69         g_free (pyg_pointer_get_ptr (self));
  70     }
  71
  72     if (info != NULL) {
  73         g_base_info_unref (info);
  74     }
  75
  76     Py_TYPE (self)->tp_free ((PyObject *)self);
  77 }
  78
  79 static PyObject *
  80 _struct_new (PyTypeObject *type,
  81              PyObject     *args,
  82              PyObject     *kwargs)
  83 {
  84     static char *kwlist[] = { NULL };
  85
  86     GIBaseInfo *info;
  87     gsize size;
  88     gpointer pointer;
  89     PyObject *self = NULL;
  90
  91     if (!PyArg_ParseTupleAndKeywords (args, kwargs, "", kwlist)) {
  92         return NULL;
  93     }
  94
  95     info = _struct_get_info ( (PyObject *) type );
  96     if (info == NULL) {
  97         if (PyErr_ExceptionMatches (PyExc_AttributeError)) {
  98             PyErr_Format (PyExc_TypeError, "missing introspection information");
  99         }
 100         return NULL;
 101     }
 102
 103     size = g_struct_info_get_size ( (GIStructInfo *) info);
 104     if (size == 0) {
 105         PyErr_Format (PyExc_TypeError,
 106             "struct cannot be created directly; try using a constructor, see: help(%s.%s)",
 107             g_base_info_get_namespace (info),
 108             g_base_info_get_name (info));
 109         goto out;
 110     }
 111     pointer = g_try_malloc0 (size);
 112     if (pointer == NULL) {
 113         PyErr_NoMemory();
 114         goto out;
 115     }
 116
 117     self = _pygi_struct_new (type, pointer, TRUE);
 118     if (self == NULL) {
 119         g_free (pointer);
 120     }
 121
 122 out:
 123     g_base_info_unref (info);
 124
 125     return (PyObject *) self;
 126 }
 127
 128 static int
 129 _struct_init (PyObject *self,
 130               PyObject *args,
 131               PyObject *kwargs)
 132 {
 133     /* Don't call PyGPointer's init, which raises an exception. */
 134     return 0;
 135 }
 136
 137 PYGLIB_DEFINE_TYPE("gi.Struct", PyGIStruct_Type, PyGIStruct);
 138
 139
 140 PyObject *
 141 _pygi_struct_new_from_g_type (GType g_type,
 142                               gpointer      pointer,
 143                               gboolean      free_on_dealloc)
 144 {
 145     PyGIStruct *self;
 146     PyTypeObject *type;
 147
 148     type = (PyTypeObject *)pygi_type_import_by_g_type (g_type);
 149
 150     if (!type)
 151         type = (PyTypeObject *)&PyGIStruct_Type; /* fallback */
 152
 153     if (!PyType_IsSubtype (type, &PyGIStruct_Type)) {
 154         PyErr_SetString (PyExc_TypeError, "must be a subtype of gi.Struct");
 155         return NULL;
 156     }
 157
 158     self = (PyGIStruct *) type->tp_alloc (type, 0);
 159     if (self == NULL) {
 160         return NULL;
 161     }
 162
 163     pyg_pointer_set_ptr (self, pointer);
 164     ( (PyGPointer *) self)->gtype = g_type;
 165     self->free_on_dealloc = free_on_dealloc;
 166
 167     return (PyObject *) self;
 168 }
 169
 170
 171 PyObject *
 172 _pygi_struct_new (PyTypeObject *type,
 173                   gpointer      pointer,
 174                   gboolean      free_on_dealloc)
 175 {
 176     PyGIStruct *self;
 177     GType g_type;
 178
 179     if (!PyType_IsSubtype (type, &PyGIStruct_Type)) {
 180         PyErr_SetString (PyExc_TypeError, "must be a subtype of gi.Struct");
 181         return NULL;
 182     }
 183
 184     self = (PyGIStruct *) type->tp_alloc (type, 0);
 185     if (self == NULL) {
 186         return NULL;
 187     }
 188
 189     g_type = pyg_type_from_object ( (PyObject *) type);
 190
 191     pyg_pointer_set_ptr (self, pointer);
 192     ( (PyGPointer *) self)->gtype = g_type;
 193     self->free_on_dealloc = free_on_dealloc;
 194
 195     return (PyObject *) self;
 196 }
 197
 198 static PyObject *
 199 _struct_repr(PyGIStruct *self)
 200 {
 201     PyObject* repr;
 202     GIBaseInfo *info;
 203     PyGPointer *pointer = (PyGPointer *)self;
 204
 205     info = _struct_get_info ((PyObject *)self);
 206     if (info == NULL)
 207         return NULL;
 208
 209     repr = PYGLIB_PyUnicode_FromFormat ("<%s.%s object at %p (%s at %p)>",
 210                                         g_base_info_get_namespace (info),
 211                                         g_base_info_get_name (info),
 212                                         self, g_type_name (pointer->gtype),
 213                                         pointer->pointer);
 214
 215     g_base_info_unref (info);
 216
 217     return repr;
 218 }
 219
 220 void
 221 _pygi_struct_register_types (PyObject *m)
 222 {
 223     Py_TYPE(&PyGIStruct_Type) = &PyType_Type;
 224     PyGIStruct_Type.tp_base = &PyGPointer_Type;
 225     PyGIStruct_Type.tp_new = (newfunc) _struct_new;
 226     PyGIStruct_Type.tp_init = (initproc) _struct_init;
 227     PyGIStruct_Type.tp_dealloc = (destructor) _struct_dealloc;
 228     PyGIStruct_Type.tp_flags = (Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE);
 229     PyGIStruct_Type.tp_repr = (reprfunc)_struct_repr;
 230
 231     if (PyType_Ready (&PyGIStruct_Type))
 232         return;
 233     if (PyModule_AddObject (m, "Struct", (PyObject *) &PyGIStruct_Type))
 234         return;
 235 }