include/vlc_objects.h

   1 /*****************************************************************************
   2  * vlc_objects.h: vlc_object_t definition and manipulation methods
   3  *****************************************************************************
   4  * Copyright (C) 2002-2008 VLC authors and VideoLAN
   5  * $Id$
   6  *
   7  * Authors: Samuel Hocevar <sam@zoy.org>
   8  *
   9  * This program is free software; you can redistribute it and/or modify it
  10  * under the terms of the GNU Lesser General Public License as published by
  11  * the Free Software Foundation; either version 2.1 of the License, or
  12  * (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  17  * GNU Lesser General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU Lesser General Public License
  20  * along with this program; if not, write to the Free Software Foundation,
  21  * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  22  *****************************************************************************/
  23
  24 /**
  25  * \defgroup vlc_object VLC objects
  26  * @{
  27  * \file
  28  * Common VLC object defintions
  29  */
  30
  31 /**
  32  * VLC object common members
  33  *
  34  * Common public properties for all VLC objects.
  35  * Object also have private properties maintained by the core, see
  36  * \ref vlc_object_internals_t
  37  */
  38 struct vlc_common_members
  39 {
  40     /** Object type name
  41      *
  42      * A constant string identifying the type of the object (for logging)
  43      */
  44     const char *object_type;
  45
  46     /** Log messages header
  47      *
  48      * Human-readable header for log messages. This is not thread-safe and
  49      * only used by VLM and Lua interfaces.
  50      */
  51     char *header;
  52
  53     int  flags;
  54
  55     /** Module probe flag
  56      *
  57      * A boolean during module probing when the probe is "forced".
  58      * See \ref module_need().
  59      */
  60     bool force;
  61
  62     /** LibVLC instance
  63      *
  64      * Root VLC object of the objects tree that this object belongs in.
  65      */
  66     libvlc_int_t *libvlc;
  67
  68     /** Parent object
  69      *
  70      * The parent VLC object in the objects tree. For the root (the LibVLC
  71      * instance) object, this is NULL.
  72      */
  73     vlc_object_t *parent;
  74 };
  75
  76 /**
  77  * Type-safe vlc_object_t cast
  78  *
  79  * This macro attempts to cast a pointer to a compound type to a
  80  * \ref vlc_object_t pointer in a type-safe manner.
  81  * It checks if the compound type actually starts with an embedded
  82  * \ref vlc_object_t structure.
  83  */
  84 #if !defined(__cplusplus)
  85 # define VLC_OBJECT(x) \
  86     _Generic((x)->obj, \
  87         struct vlc_common_members: (vlc_object_t *)(&(x)->obj), \
  88         const struct vlc_common_members: (const vlc_object_t *)(&(x)->obj) \
  89     )
  90 #else
  91 # define VLC_OBJECT( x ) ((vlc_object_t *)&(x)->obj)
  92 #endif
  93
  94 /* Object flags */
  95 #define OBJECT_FLAGS_QUIET       0x0002
  96 #define OBJECT_FLAGS_NOINTERACT  0x0004
  97
  98 /*****************************************************************************
  99  * The vlc_object_t type. Yes, it's that simple :-)
 100  *****************************************************************************/
 101 /** The main vlc_object_t structure */
 102 struct vlc_object_t
 103 {
 104     struct vlc_common_members obj;
 105 };
 106
 107 /* The root object */
 108 struct libvlc_int_t
 109 {
 110     struct vlc_common_members obj;
 111 };
 112
 113 /*****************************************************************************
 114  * Prototypes
 115  *****************************************************************************/
 116 VLC_API void *vlc_object_create( vlc_object_t *, size_t ) VLC_MALLOC VLC_USED;
 117 VLC_API vlc_object_t *vlc_object_find_name( vlc_object_t *, const char * ) VLC_USED VLC_DEPRECATED;
 118 VLC_API void * vlc_object_hold( vlc_object_t * );
 119 VLC_API void vlc_object_release( vlc_object_t * );
 120 VLC_API vlc_list_t *vlc_list_children( vlc_object_t * ) VLC_USED;
 121 VLC_API void vlc_list_release( vlc_list_t * );
 122 VLC_API char *vlc_object_get_name( const vlc_object_t * ) VLC_USED;
 123 #define vlc_object_get_name(o) vlc_object_get_name(VLC_OBJECT(o))
 124
 125 #define vlc_object_create(a,b) vlc_object_create( VLC_OBJECT(a), b )
 126
 127 #define vlc_object_find_name(a,b) \
 128     vlc_object_find_name( VLC_OBJECT(a),b)
 129
 130 #define vlc_object_hold(a) \
 131     vlc_object_hold( VLC_OBJECT(a) )
 132
 133 #define vlc_object_release(a) \
 134     vlc_object_release( VLC_OBJECT(a) )
 135
 136 #define vlc_list_children(a) \
 137     vlc_list_children( VLC_OBJECT(a) )
 138
 139 VLC_API VLC_MALLOC void *vlc_obj_malloc(vlc_object_t *, size_t);
 140 VLC_API VLC_MALLOC void *vlc_obj_calloc(vlc_object_t *, size_t, size_t);
 141 VLC_API void vlc_obj_free(vlc_object_t *, void *);
 142
 143 /** @} */