1 /* GStreamer

     2  * Copyright (C) 1999,2000 Erik Walthinsen <omega@cse.ogi.edu>

     3  *                    2000 Wim Taymans <wtay@chello.be>

     4  *

     5  * gstinterface.h: Declarations of interface stuff

     6  *

     7  * This library is free software; you can redistribute it and/or

     8  * modify it under the terms of the GNU Library General Public

     9  * License as published by the Free Software Foundation; either

    10  * version 2 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  * Library General Public License for more details.

    16  *

    17  * You should have received a copy of the GNU Library General Public

    18  * License along with this library; if not, write to the

    19  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,

    20  * Boston, MA 02111-1307, USA.

    21  */

    22 

    23 #ifndef __GST_IMPLEMENTS_INTERFACE_H__

    24 #define __GST_IMPLEMENTS_INTERFACE_H__

    25 

    26 #include <gst/gstelement.h>

    27 

    28 G_BEGIN_DECLS

    29 

    30 #define GST_TYPE_IMPLEMENTS_INTERFACE \

    31   (gst_implements_interface_get_type ())

    32 #define GST_IMPLEMENTS_INTERFACE(obj) \

    33   (G_TYPE_CHECK_INSTANCE_CAST ((obj), GST_TYPE_IMPLEMENTS_INTERFACE, \

    34 				      GstImplementsInterface))

    35 #define GST_IMPLEMENTS_INTERFACE_CLASS(klass) \

    36   (G_TYPE_CHECK_CLASS_CAST ((klass), GST_TYPE_IMPLEMENTS_INTERFACE, \

    37 			    GstImplementsInterfaceClass))

    38 #define GST_IS_IMPLEMENTS_INTERFACE(obj) \

    39   (G_TYPE_CHECK_INSTANCE_TYPE ((obj), GST_TYPE_IMPLEMENTS_INTERFACE))

    40 #define GST_IS_IMPLEMENTS_INTERFACE_CLASS(klass) \

    41   (G_TYPE_CHECK_CLASS_TYPE ((klass), GST_TYPE_IMPLEMENTS_INTERFACE))

    42 #define GST_IMPLEMENTS_INTERFACE_GET_CLASS(inst) \

    43   (G_TYPE_INSTANCE_GET_INTERFACE ((inst), GST_TYPE_IMPLEMENTS_INTERFACE, \

    44 				  GstImplementsInterfaceClass))

    45 

    46 /**

    47  * GstImplementsInterface:

    48  *

    49  * Opaque #GstImplementsInterface structure.

    50  */

    51 typedef struct _GstImplementsInterface GstImplementsInterface;

    52 

    53 typedef struct _GstImplementsInterfaceClass GstImplementsInterfaceClass;

    54 

    55 /* This small extra virtual function is here to provide an

    56  * interface functionality on a per-instance basis rather

    57  * than a per-class basis, which is the case for glib.

    58  */

    59 struct _GstImplementsInterfaceClass {

    60   GTypeInterface parent;

    61 

    62   /* virtual functions */

    63   gboolean (* supported) (GstImplementsInterface *iface,

    64 			  GType                   iface_type);

    65 

    66   gpointer _gst_reserved[GST_PADDING];

    67 };

    68 

    69 #define GST_IMPLEMENTS_INTERFACE_CHECK_INSTANCE_CAST(obj, type, cast_t) \

    70   ((cast_t *) gst_implements_interface_cast ((obj), (type)))

    71 #define GST_IMPLEMENTS_INTERFACE_CHECK_INSTANCE_TYPE(obj, type) \

    72   (gst_implements_interface_check ((obj), (type)))

    73 

    74 GType	 gst_implements_interface_get_type    (void);

    75 

    76 /* wrapper functions to check for functionality implementation */

    77 #ifdef __SYMBIAN32__

    78 IMPORT_C

    79 #endif

    80 

    81 gboolean gst_element_implements_interface     (GstElement *element,

    82 					       GType       iface_type);

    83 #ifdef __SYMBIAN32__

    84 IMPORT_C

    85 #endif

    86 

    87 gpointer gst_implements_interface_cast	      (gpointer    from,

    88 					       GType       type);

    89 #ifdef __SYMBIAN32__

    90 IMPORT_C

    91 #endif

    92 

    93 gboolean gst_implements_interface_check	      (gpointer    from,

    94 					       GType       type);

    95 

    96 G_END_DECLS

    97 

    98 #endif /* __GST_IMPLEMENTS_INTERFACE_H__ */