gi/pygi-boxed.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-boxed.c: wrapper to handle 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-boxed.h"
  23 #include "pygi-info.h"
  24 #include "pygboxed.h"
  25 #include "pygi-type.h"
  26 #include "pygi-basictype.h"
  27 #include "pygi-python-compat.h"
  28
  29 #include <girepository.h>
  30
  31 static void
  32 boxed_dealloc (PyGIBoxed *self)
  33 {
  34     Py_TYPE (self)->tp_free ((PyObject *)self);
  35 }
  36
  37 static PyObject *
  38 boxed_del (PyGIBoxed *self)
  39 {
  40     GType g_type;
  41     gpointer boxed = pyg_boxed_get_ptr (self);
  42
  43     if ( ( (PyGBoxed *) self)->free_on_dealloc && boxed != NULL) {
  44         if (self->slice_allocated) {
  45             g_slice_free1 (self->size, boxed);
  46             self->slice_allocated = FALSE;
  47             self->size = 0;
  48         } else {
  49             g_type = pyg_type_from_object ( (PyObject *) self);
  50             g_boxed_free (g_type, boxed);
  51         }
  52     }
  53     pyg_boxed_set_ptr (self, NULL);
  54
  55     Py_RETURN_NONE;
  56 }
  57
  58 void *
  59 pygi_boxed_alloc (GIBaseInfo *info, gsize *size_out)
  60 {
  61     gpointer boxed = NULL;
  62     gsize size = 0;
  63
  64     switch (g_base_info_get_type (info)) {
  65         case GI_INFO_TYPE_UNION:
  66             size = g_union_info_get_size ( (GIUnionInfo *) info);
  67             break;
  68         case GI_INFO_TYPE_BOXED:
  69         case GI_INFO_TYPE_STRUCT:
  70             size = g_struct_info_get_size ( (GIStructInfo *) info);
  71             break;
  72         default:
  73             PyErr_Format (PyExc_TypeError,
  74                           "info should be Boxed or Union, not '%d'",
  75                           g_base_info_get_type (info));
  76             return NULL;
  77     }
  78
  79     if (size == 0) {
  80         PyErr_Format (PyExc_TypeError,
  81             "boxed cannot be created directly; try using a constructor, see: help(%s.%s)",
  82             g_base_info_get_namespace (info),
  83             g_base_info_get_name (info));
  84         return NULL;
  85     }
  86
  87     if( size_out != NULL)
  88         *size_out = size;
  89
  90     boxed = g_slice_alloc0 (size);
  91     if (boxed == NULL)
  92         PyErr_NoMemory();
  93     return boxed;
  94 }
  95
  96 static PyObject *
  97 boxed_new (PyTypeObject *type,
  98             PyObject     *args,
  99             PyObject     *kwargs)
 100 {
 101     GIBaseInfo *info;
 102     gsize size = 0;
 103     gpointer boxed;
 104     PyGIBoxed *self = NULL;
 105
 106     info = _pygi_object_get_gi_info ( (PyObject *) type, &PyGIBaseInfo_Type);
 107     if (info == NULL) {
 108         if (PyErr_ExceptionMatches (PyExc_AttributeError)) {
 109             PyErr_Format (PyExc_TypeError, "missing introspection information");
 110         }
 111         return NULL;
 112     }
 113
 114     boxed = pygi_boxed_alloc (info, &size);
 115     if (boxed == NULL) {
 116         goto out;
 117     }
 118
 119     self = (PyGIBoxed *) pygi_boxed_new (type, boxed, TRUE, size);
 120     if (self == NULL) {
 121         g_slice_free1 (size, boxed);
 122         goto out;
 123     }
 124
 125     self->size = size;
 126     self->slice_allocated = TRUE;
 127
 128 out:
 129     g_base_info_unref (info);
 130
 131     return (PyObject *) self;
 132 }
 133
 134 static int
 135 boxed_init (PyObject *self,
 136              PyObject *args,
 137              PyObject *kwargs)
 138 {
 139     static char *kwlist[] = { NULL };
 140
 141     if (!PyArg_ParseTupleAndKeywords (args, kwargs, "", kwlist)) {
 142         PyErr_Clear ();
 143         PyErr_Warn (PyExc_DeprecationWarning,
 144                 "Passing arguments to gi.types.Boxed.__init__() is deprecated. "
 145                 "All arguments passed will be ignored.");
 146     }
 147
 148     /* Don't call PyGBoxed's init, which raises an exception. */
 149     return 0;
 150 }
 151
 152 PYGLIB_DEFINE_TYPE("gi.Boxed", PyGIBoxed_Type, PyGIBoxed);
 153
 154 PyObject *
 155 pygi_boxed_new (PyTypeObject *type,
 156                 gpointer      boxed,
 157                 gboolean      free_on_dealloc,
 158                 gsize         allocated_slice)
 159 {
 160     PyGIBoxed *self;
 161
 162     if (!boxed) {
 163         Py_RETURN_NONE;
 164     }
 165
 166     if (!PyType_IsSubtype (type, &PyGIBoxed_Type)) {
 167         PyErr_SetString (PyExc_TypeError, "must be a subtype of gi.Boxed");
 168         return NULL;
 169     }
 170
 171     self = (PyGIBoxed *) type->tp_alloc (type, 0);
 172     if (self == NULL) {
 173         return NULL;
 174     }
 175
 176     ( (PyGBoxed *) self)->gtype = pyg_type_from_object ( (PyObject *) type);
 177     ( (PyGBoxed *) self)->free_on_dealloc = free_on_dealloc;
 178     pyg_boxed_set_ptr (self, boxed);
 179     if (allocated_slice > 0) {
 180         self->size = allocated_slice;
 181         self->slice_allocated = TRUE;
 182     } else {
 183         self->size = 0;
 184         self->slice_allocated = FALSE;
 185     }
 186
 187     return (PyObject *) self;
 188 }
 189
 190 static PyObject *
 191 boxed_get_free_on_dealloc(PyGIBoxed *self, void *closure)
 192 {
 193   return pygi_gboolean_to_py( ((PyGBoxed *)self)->free_on_dealloc );
 194 }
 195
 196 static PyObject *
 197 boxed_get_is_valid (PyGIBoxed *self, void *closure)
 198 {
 199   return pygi_gboolean_to_py (pyg_boxed_get_ptr (self) != NULL);
 200 }
 201
 202 /**
 203  * pygi_boxed_copy_in_place:
 204  *
 205  * Replace the boxed pointer held by this wrapper with a boxed copy
 206  * freeing the previously held pointer (when free_on_dealloc is TRUE).
 207  * This can be used in cases where Python is passed a reference which
 208  * it does not own and the wrapper is held by the Python program
 209  * longer than the duration of a callback it was passed to.
 210  */
 211 void
 212 pygi_boxed_copy_in_place (PyGIBoxed *self)
 213 {
 214     PyGBoxed *pygboxed = (PyGBoxed *)self;
 215     gpointer ptr = pyg_boxed_get_ptr (self);
 216     gpointer copy = NULL;
 217
 218     if (ptr)
 219         copy = g_boxed_copy (pygboxed->gtype, ptr);
 220
 221     boxed_del (self);
 222     pyg_boxed_set_ptr (pygboxed, copy);
 223     pygboxed->free_on_dealloc = TRUE;
 224 }
 225
 226 static PyGetSetDef pygi_boxed_getsets[] = {
 227     { "_free_on_dealloc", (getter)boxed_get_free_on_dealloc, (setter)0 },
 228     { "_is_valid", (getter)boxed_get_is_valid, (setter)0 },
 229     { NULL, 0, 0 }
 230 };
 231
 232 static PyMethodDef boxed_methods[] = {
 233     { "__del__", (PyCFunction)boxed_del, METH_NOARGS },
 234     { NULL, NULL, 0 }
 235 };
 236
 237 /**
 238  * Returns 0 on success, or -1 and sets an exception.
 239  */
 240 int
 241 pygi_boxed_register_types (PyObject *m)
 242 {
 243     Py_TYPE(&PyGIBoxed_Type) = &PyType_Type;
 244     g_assert (Py_TYPE (&PyGBoxed_Type) != NULL);
 245     PyGIBoxed_Type.tp_base = &PyGBoxed_Type;
 246     PyGIBoxed_Type.tp_new = (newfunc) boxed_new;
 247     PyGIBoxed_Type.tp_init = (initproc) boxed_init;
 248     PyGIBoxed_Type.tp_dealloc = (destructor) boxed_dealloc;
 249     PyGIBoxed_Type.tp_flags = (Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE);
 250     PyGIBoxed_Type.tp_getset = pygi_boxed_getsets;
 251     PyGIBoxed_Type.tp_methods = boxed_methods;
 252
 253     if (PyType_Ready (&PyGIBoxed_Type) < 0)
 254         return -1;
 255     Py_INCREF ((PyObject *) &PyGIBoxed_Type);
 256     if (PyModule_AddObject (m, "Boxed", (PyObject *) &PyGIBoxed_Type) < 0) {
 257         Py_DECREF ((PyObject *) &PyGIBoxed_Type);
 258         return -1;
 259     }
 260
 261     return 0;
 262 }