text: /* GStreamer
   * Copyright (C) 2005 David Schleef <ds@schleef.org>
   *
   * gstminiobject.h: Header for GstMiniObject
   *
   * 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.
   */
  
  
  #ifndef __GST_MINI_OBJECT_H__
  #define __GST_MINI_OBJECT_H__
  
  #include <gst/gstconfig.h>
  
  #include <glib-object.h>
  
  G_BEGIN_DECLS
  
  #define GST_TYPE_MINI_OBJECT          (gst_mini_object_get_type())
  #define GST_IS_MINI_OBJECT(obj)       (G_TYPE_CHECK_INSTANCE_TYPE ((obj), GST_TYPE_MINI_OBJECT))
  #define GST_IS_MINI_OBJECT_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE ((klass), GST_TYPE_MINI_OBJECT))
  #define GST_MINI_OBJECT_GET_CLASS(obj) (G_TYPE_INSTANCE_GET_CLASS ((obj), GST_TYPE_MINI_OBJECT, GstMiniObjectClass))
  #define GST_MINI_OBJECT(obj)          (G_TYPE_CHECK_INSTANCE_CAST ((obj), GST_TYPE_MINI_OBJECT, GstMiniObject))
  #define GST_MINI_OBJECT_CLASS(klass)  (G_TYPE_CHECK_CLASS_CAST ((klass), GST_TYPE_MINI_OBJECT, GstMiniObjectClass))
  #define GST_MINI_OBJECT_CAST(obj)     ((GstMiniObject*)(obj))
  #define GST_MINI_OBJECT_CONST_CAST(obj) ((const GstMiniObject*)(obj))
  
  typedef struct _GstMiniObject GstMiniObject;
  typedef struct _GstMiniObjectClass GstMiniObjectClass;
  
  /**
   * GstMiniObjectCopyFunction:
   * @obj: MiniObject to copy
   *
   * Virtual function prototype for methods to create copies of instances.
   *
   * Returns: reference to cloned instance.
   */
  typedef GstMiniObject * (*GstMiniObjectCopyFunction) (const GstMiniObject *obj);
  /**
   * GstMiniObjectFinalizeFunction:
   * @obj: MiniObject to finalize
   *
   * Virtual function prototype for methods to free ressources used by
   * mini-objects. Subclasses of the mini object are allowed to revive the
   * passed object by doing a gst_mini_object_ref(). If the object is not
   * revived after the finalize function, the memory associated with the
   * object is freed.
   */
  typedef void (*GstMiniObjectFinalizeFunction) (GstMiniObject *obj);
  
  /**
   * GST_MINI_OBJECT_FLAGS:
   * @obj: MiniObject to return flags for.
   *
   * This macro returns the entire set of flags for the mini-object.
   */
  #define GST_MINI_OBJECT_FLAGS(obj)  (GST_MINI_OBJECT_CAST(obj)->flags)
  /**
   * GST_MINI_OBJECT_FLAG_IS_SET:
   * @obj: MiniObject to check for flags.
   * @flag: Flag to check for
   *
   * This macro checks to see if the given flag is set.
   */
  #define GST_MINI_OBJECT_FLAG_IS_SET(obj,flag)        !!(GST_MINI_OBJECT_FLAGS (obj) & (flag))
  /**
   * GST_MINI_OBJECT_FLAG_SET:
   * @obj: MiniObject to set flag in.
   * @flag: Flag to set, can by any number of bits in guint32.
   *
   * This macro sets the given bits.
   */
  #define GST_MINI_OBJECT_FLAG_SET(obj,flag)           (GST_MINI_OBJECT_FLAGS (obj) |= (flag))
  /**
   * GST_MINI_OBJECT_FLAG_UNSET:
   * @obj: MiniObject to unset flag in.
   * @flag: Flag to set, must be a single bit in guint32.
   *
   * This macro usets the given bits.
   */
  #define GST_MINI_OBJECT_FLAG_UNSET(obj,flag)         (GST_MINI_OBJECT_FLAGS (obj) &= ~(flag))
  
  /**
   * GST_VALUE_HOLDS_MINI_OBJECT:
   * @value: the #GValue to check
   *
   * Checks if the given #GValue contains a #GST_TYPE_MINI_OBJECT value.
   */
  #define GST_VALUE_HOLDS_MINI_OBJECT(value)  (G_VALUE_HOLDS(value, GST_TYPE_MINI_OBJECT))
  
  /**
   * GstMiniObjectFlags:
   * @GST_MINI_OBJECT_FLAG_READONLY: is the miniobject readonly or writable
   * @GST_MINI_OBJECT_FLAG_RESERVED1: a flag reserved for internal use e.g. as
   *     GST_BUFFER_FLAG_MEDIA4. Since: 0.10.33.
   * @GST_MINI_OBJECT_FLAG_LAST: first flag that can be used by subclasses.
   *
   * Flags for the mini object
   */
  
  typedef enum
  {
    GST_MINI_OBJECT_FLAG_READONLY = (1<<0),
    GST_MINI_OBJECT_FLAG_RESERVED1 = (1<<1),
    /* padding */
    GST_MINI_OBJECT_FLAG_LAST = (1<<4)
  } GstMiniObjectFlags;
  
  /**
   * GST_MINI_OBJECT_REFCOUNT:
   * @obj: a #GstMiniObject
   *
   * Get access to the reference count field of the mini-object.
   */
  #define GST_MINI_OBJECT_REFCOUNT(obj)           ((GST_MINI_OBJECT_CAST(obj))->refcount)
  /**
   * GST_MINI_OBJECT_REFCOUNT_VALUE:
   * @obj: a #GstMiniObject
   *
   * Get the reference count value of the mini-object.
   */
  #define GST_MINI_OBJECT_REFCOUNT_VALUE(obj)     (g_atomic_int_get (&(GST_MINI_OBJECT_CAST(obj))->refcount))
  
  /**
   * GstMiniObjectWeakNotify:
   * @data: data that was provided when the weak reference was established
   * @where_the_mini_object_was: the mini object being finalized
   * 
   * A #GstMiniObjectWeakNotify function can be added to a mini object as a
   * callback that gets triggered when the mini object is finalized. Since the
   * mini object is already being finalized when the #GstMiniObjectWeakNotify is
   * called, there's not much you could do with the object, apart from e.g. using
   * its adress as hash-index or the like. 
   *
   * Since: 0.10.35
   *
   */
  typedef void (*GstMiniObjectWeakNotify) (gpointer data,
      GstMiniObject * where_the_mini_object_was);
  
  typedef struct _GstMiniObjectPrivate GstMiniObjectPrivate;
  
  /**
   * GstMiniObject:
   * @instance: type instance
   * @refcount: atomic refcount
   * @flags: extra flags.
   * 
   * Base class for refcounted lightweight objects.
   * Ref Func: gst_mini_object_ref
   * Unref Func: gst_mini_object_unref
   * Set Value Func: gst_value_set_mini_object
   * Get Value Func: gst_value_get_mini_object
   */
  struct _GstMiniObject {
    GTypeInstance instance;
    /*< public >*/ /* with COW */
    gint refcount;
    guint flags;
  
    /*< private >*/
    GstMiniObjectPrivate *priv;
  };
  
  struct _GstMiniObjectClass {
    GTypeClass type_class;
  
    GstMiniObjectCopyFunction copy;
    GstMiniObjectFinalizeFunction finalize;
  
    /*< private >*/
    gpointer _gst_reserved;
  };
  
  GType 		gst_mini_object_get_type 	(void);
  
  GstMiniObject* 	gst_mini_object_new 		(GType type) G_GNUC_MALLOC;
  GstMiniObject* 	gst_mini_object_copy 		(const GstMiniObject *mini_object) G_GNUC_MALLOC;
  gboolean 	gst_mini_object_is_writable 	(const GstMiniObject *mini_object);
  GstMiniObject*  gst_mini_object_make_writable 	(GstMiniObject *mini_object);
  
  /* refcounting */
  GstMiniObject* 	gst_mini_object_ref 		(GstMiniObject *mini_object);
  void 		gst_mini_object_unref 		(GstMiniObject *mini_object);
  void	        gst_mini_object_weak_ref        (GstMiniObject *object,
  					         GstMiniObjectWeakNotify notify,
  					         gpointer data);
  void	        gst_mini_object_weak_unref	(GstMiniObject *object,
  					         GstMiniObjectWeakNotify notify,
  					         gpointer data);
  void 		gst_mini_object_replace 	(GstMiniObject **olddata, GstMiniObject *newdata);
  
  /* GParamSpec */
  
  #define	GST_TYPE_PARAM_MINI_OBJECT	        (gst_param_spec_mini_object_get_type())
  #define GST_IS_PARAM_SPEC_MINI_OBJECT(pspec)    (G_TYPE_CHECK_INSTANCE_TYPE ((pspec), \
                                                   GST_TYPE_PARAM_MINI_OBJECT))
  #define GST_PARAM_SPEC_MINI_OBJECT(pspec)       (G_TYPE_CHECK_INSTANCE_CAST ((pspec), \
                                                   GST_TYPE_PARAM_MINI_OBJECT, \
  						 GstParamSpecMiniObject))
  
  typedef struct _GstParamSpecMiniObject GstParamSpecMiniObject;
  
  /**
   * GstParamSpecMiniObject:
   * @parent_instance: private %GParamSpec portion
   * 
   * A %GParamSpec derived structure that contains the meta data
   * for %GstMiniObject properties.
   */
  struct _GstParamSpecMiniObject
  {
    GParamSpec parent_instance;
  };
  
  
  GType gst_param_spec_mini_object_get_type (void);
  
  GParamSpec* 	gst_param_spec_mini_object 	(const char *name, const char *nick,
      						 const char *blurb, GType object_type, 
  						 GParamFlags flags) G_GNUC_MALLOC;
  
  /* GValue stuff */
  
  void 		gst_value_set_mini_object 	(GValue *value, GstMiniObject *mini_object);
  void 		gst_value_take_mini_object 	(GValue *value, GstMiniObject *mini_object);
  GstMiniObject* 	gst_value_get_mini_object 	(const GValue *value);
  GstMiniObject*  gst_value_dup_mini_object       (const GValue *value);
  
  
  G_END_DECLS
  
  #endif
  
  