gstreamer/gst/pygstiterator.c

/* -*- Mode: C; c-basic-offset: 4 -*- */
/* gst-python
 * Copyright (C) 2005 Johan Dahlin
 *
 * 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., 59 Temple Place - Suite 330,
 * Boston, MA 02111-1307, USA.
 * 
 * Author: Johan Dahlin <johan@gnome.org>
 */
/* define this for all source files that don't run init_pygobject()
 * before including pygobject.h */
#define NO_IMPORT_PYGOBJECT

#include "common.h"

static void
pygst_iterator_dealloc (PyGstIterator * self)
{
  gst_iterator_free (self->iter);
  PyObject_Del ((PyObject *) self);
}

static PyObject *
pygst_iterator_iter_next (PyGstIterator * self)
{
  gpointer element;
  PyObject *retval = NULL;
  GstIteratorResult result;

  result = gst_iterator_next (self->iter, &element);
  switch (result) {
    case GST_ITERATOR_DONE:
      PyErr_SetNone (PyExc_StopIteration);
      break;
    case GST_ITERATOR_OK:
      if (g_type_is_a (self->iter->type, G_TYPE_OBJECT)) {
        retval = pygobject_new (G_OBJECT (element));
        g_object_unref (element);
      } else if (g_type_is_a (self->iter->type, GST_TYPE_MINI_OBJECT)) {
        retval = pygstminiobject_new (GST_MINI_OBJECT (element));
        gst_mini_object_unref (element);
      } else {
        const gchar *type_name;

        type_name = g_type_name (self->iter->type);
        PyErr_Format (PyExc_TypeError, "Unsupported child type: %s",
            type_name ? type_name : "unknown");
      }
      break;
    case GST_ITERATOR_RESYNC:
      /* XXX: add/raise gst.IteratorResync */
      PyErr_SetString (PyExc_TypeError, "Resync");
      break;
    case GST_ITERATOR_ERROR:
      PyErr_SetString (PyExc_TypeError, "Error");
      break;
    default:
      g_assert_not_reached ();
      break;
  }
  return retval;
}

static PyObject *
pygst_iterator_next (PyGstIterator * self)
{
  /* Be compatible with Pythons API rather than GStreamers */
  return pygst_iterator_iter_next (self);
}

static PyObject *
pygst_iterator_push (PyGstIterator * self, PyObject * args)
{
  PyGstIterator *other;

  if (!PyArg_ParseTuple (args, "O!:push", &PyGstIterator_Type, &other))
    return NULL;

  gst_iterator_push (self->iter, other->iter);

  Py_INCREF (Py_None);
  return Py_None;
}

static PyObject *
pygst_iterator_resync (PyGstIterator * self)
{
  gst_iterator_resync (self->iter);

  Py_INCREF (Py_None);
  return Py_None;
}

static PyMethodDef _PyGstIterator_methods[] = {
  {"next", (PyCFunction) pygst_iterator_next, METH_NOARGS},
  {"push", (PyCFunction) pygst_iterator_push, METH_VARARGS},
  {"resync", (PyCFunction) pygst_iterator_resync, METH_NOARGS},
  {NULL, NULL, 0}
};

PyTypeObject PyGstIterator_Type = {
  PyObject_HEAD_INIT (NULL)
      0,                        /* ob_size */
  "gst.Iterator",               /* tp_name */
  sizeof (PyGstIterator),       /* tp_basicsize */
  0,                            /* tp_itemsize */
  (destructor) pygst_iterator_dealloc,  /* tp_dealloc */
  0,                            /* tp_print */
  0,                            /* tp_getattr */
  0,                            /* tp_setattr */
  0,                            /* tp_compare */
  0,                            /* tp_repr */
  0,                            /* tp_as_number */
  0,                            /* tp_as_sequence */
  0,                            /* tp_as_mapping */
  0,                            /* tp_hash */
  0,                            /* tp_call */
  0,                            /* tp_str */
  0,                            /* tp_getattro */
  0,                            /* tp_setattro */
  0,                            /* tp_as_buffer */
  Py_TPFLAGS_DEFAULT,           /* tp_flags */
  "GstIterator wrapper",        /* tp_doc */
  0,                            /* tp_traverse */
  0,                            /* tp_clear */
  0,                            /* tp_richcompare */
  0,                            /* tp_weaklistoffset */
  PyObject_SelfIter,            /* tp_iter */
  (iternextfunc) pygst_iterator_iter_next,      /* tp_iternext */
  _PyGstIterator_methods,       /* tp_methods */
};

PyObject *
pygst_iterator_new (GstIterator * iter)
{
  PyGstIterator *self;

  if (iter == NULL) {
      PyErr_SetString (PyExc_TypeError, "Invalid GstIterator (NULL)");
      return NULL;
  }

  self = PyObject_NEW (PyGstIterator, &PyGstIterator_Type);
  self->iter = iter;
  GST_DEBUG ("self:%p , iterator:%p, type:%lu",
      self, self->iter, self->iter->type);
  return (PyObject *) self;
}