/* 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., 51 Franklin St, Fifth Floor,

 * Boston, MA 02110-1301, USA.

 */

#ifndef __GST_MINI_OBJECT_H__

#define __GST_MINI_OBJECT_H__

#include <gst/gstconfig.h>

#include <glib-object.h>

G_BEGIN_DECLS

#define GST_IS_MINI_OBJECT_TYPE(obj,type)  ((obj) && GST_MINI_OBJECT_TYPE(obj) == (type))

#define GST_MINI_OBJECT_CAST(obj)          ((GstMiniObject*)(obj))

#define GST_MINI_OBJECT_CONST_CAST(obj)    ((const GstMiniObject*)(obj))

#define GST_MINI_OBJECT(obj)               (GST_MINI_OBJECT_CAST(obj))

typedef struct _GstMiniObject GstMiniObject;

/**

 * GstMiniObjectCopyFunction:

 * @obj: MiniObject to copy

 *

 * Function prototype for methods to create copies of instances.

 *

 * Returns: reference to cloned instance.

 */

typedef GstMiniObject * (*GstMiniObjectCopyFunction) (const GstMiniObject *obj);

/**

 * GstMiniObjectDisposeFunction:

 * @obj: MiniObject to dispose

 *

 * Function prototype for when a miniobject has lost its last refcount.

 * Implementation 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 dispose function, the function should return %TRUE

 * and the memory associated with the object is freed.

 *

 * Returns: %TRUE if the object should be cleaned up.

 */

typedef gboolean (*GstMiniObjectDisposeFunction) (GstMiniObject *obj);

/**

 * GstMiniObjectFreeFunction:

 * @obj: MiniObject to free

 *

 * Virtual function prototype for methods to free resources used by

 * mini-objects.

 */

typedef void (*GstMiniObjectFreeFunction) (GstMiniObject *obj);

 /**

 * GstMiniObjectNotify:

 * @user_data: data that was provided when the notify was added

 * @obj: the mini object

 *

 * A #GstMiniObjectNotify function can be added to a mini object as a

 * callback that gets triggered when gst_mini_object_unref() drops the

 * last ref and @obj is about to be freed.

 */

typedef void (*GstMiniObjectNotify) (gpointer user_data, GstMiniObject * obj);

/**

 * GST_MINI_OBJECT_TYPE:

 * @obj: MiniObject to return type for.

 *

 * This macro returns the type of the mini-object.

 */

#define GST_MINI_OBJECT_TYPE(obj)  (GST_MINI_OBJECT_CAST(obj)->type)

/**

 * 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 unsets the given bits.

 */

#define GST_MINI_OBJECT_FLAG_UNSET(obj,flag)         (GST_MINI_OBJECT_FLAGS (obj) &= ~(flag))

/**

 * GstMiniObjectFlags:

 * @GST_MINI_OBJECT_FLAG_LOCKABLE: the object can be locked and unlocked with

 * gst_mini_object_lock() and gst_mini_object_unlock().

 * @GST_MINI_OBJECT_FLAG_LOCK_READONLY: the object is permanently locked in

 * READONLY mode. Only read locks can be performed on the object.

 * @GST_MINI_OBJECT_FLAG_MAY_BE_LEAKED: the object is expected to stay alive

 * even after gst_deinit() has been called and so should be ignored by leak

 * detection tools. (Since 1.10)

 * @GST_MINI_OBJECT_FLAG_LAST: first flag that can be used by subclasses.

 *

 * Flags for the mini object

 */

typedef enum

{

  GST_MINI_OBJECT_FLAG_LOCKABLE      = (1 << 0),

  GST_MINI_OBJECT_FLAG_LOCK_READONLY = (1 << 1),

  GST_MINI_OBJECT_FLAG_MAY_BE_LEAKED = (1 << 2),

  /* padding */

  GST_MINI_OBJECT_FLAG_LAST          = (1 << 4)

} GstMiniObjectFlags;

/**

 * GST_MINI_OBJECT_IS_LOCKABLE:

 * @obj: a #GstMiniObject

 *

 * Check if @obj is lockable. A lockable object can be locked and unlocked with

 * gst_mini_object_lock() and gst_mini_object_unlock().

 */

#define GST_MINI_OBJECT_IS_LOCKABLE(obj)  GST_MINI_OBJECT_FLAG_IS_SET(obj, GST_MINI_OBJECT_FLAG_LOCKABLE)

/**

 * GstLockFlags:

 * @GST_LOCK_FLAG_READ: lock for read access

 * @GST_LOCK_FLAG_WRITE: lock for write access

 * @GST_LOCK_FLAG_EXCLUSIVE: lock for exclusive access

 * @GST_LOCK_FLAG_LAST: first flag that can be used for custom purposes

 *

 * Flags used when locking miniobjects

 */

typedef enum {

  GST_LOCK_FLAG_READ      = (1 << 0),

  GST_LOCK_FLAG_WRITE     = (1 << 1),

  GST_LOCK_FLAG_EXCLUSIVE = (1 << 2),

  GST_LOCK_FLAG_LAST      = (1 << 8)

} GstLockFlags;

/**

 * GST_LOCK_FLAG_READWRITE: (value 3) (type GstLockFlags)

 *

 * GstLockFlags value alias for GST_LOCK_FLAG_READ | GST_LOCK_FLAG_WRITE

 */

#define GST_LOCK_FLAG_READWRITE  ((GstLockFlags) (GST_LOCK_FLAG_READ | GST_LOCK_FLAG_WRITE))

/**

 * 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))

/**

 * GstMiniObject: (ref-func gst_mini_object_ref) (unref-func gst_mini_object_unref) (set-value-func g_value_set_boxed) (get-value-func g_value_get_boxed)

 * @type: the GType of the object

 * @refcount: atomic refcount

 * @lockstate: atomic state of the locks

 * @flags: extra flags.

 * @copy: a copy function

 * @dispose: a dispose function

 * @free: the free function

 *

 * Base class for refcounted lightweight objects.

 */

struct _GstMiniObject {

  GType   type;

  /*< public >*/ /* with COW */

  gint    refcount;

  gint    lockstate;

  guint   flags;

  GstMiniObjectCopyFunction copy;

  GstMiniObjectDisposeFunction dispose;

  GstMiniObjectFreeFunction free;

  /* < private > */

  /* Used to keep track of weak ref notifies and qdata */

  guint n_qdata;

  gpointer qdata;

};

GST_API

void            gst_mini_object_init (GstMiniObject *mini_object,

                                      guint flags, GType type,

                                      GstMiniObjectCopyFunction copy_func,

                                      GstMiniObjectDisposeFunction dispose_func,

                                      GstMiniObjectFreeFunction free_func);

/* refcounting */

GST_API

GstMiniObject * gst_mini_object_ref		(GstMiniObject *mini_object);

GST_API

void            gst_mini_object_unref		(GstMiniObject *mini_object);

GST_API

void            gst_mini_object_weak_ref        (GstMiniObject *object,

					         GstMiniObjectNotify notify,

					         gpointer data);

GST_API

void            gst_mini_object_weak_unref	(GstMiniObject *object,

					         GstMiniObjectNotify notify,

					         gpointer data);

/* locking */

GST_API

gboolean        gst_mini_object_lock            (GstMiniObject *object, GstLockFlags flags);

GST_API

void            gst_mini_object_unlock          (GstMiniObject *object, GstLockFlags flags);

GST_API

gboolean        gst_mini_object_is_writable     (const GstMiniObject *mini_object);

GST_API

GstMiniObject * gst_mini_object_make_writable	(GstMiniObject *mini_object) G_GNUC_WARN_UNUSED_RESULT;

/* copy */

GST_API

GstMiniObject * gst_mini_object_copy		(const GstMiniObject *mini_object) G_GNUC_MALLOC G_GNUC_WARN_UNUSED_RESULT;

GST_API

void            gst_mini_object_set_qdata       (GstMiniObject *object, GQuark quark,

                                                 gpointer data, GDestroyNotify destroy);

GST_API

gpointer        gst_mini_object_get_qdata       (GstMiniObject *object, GQuark quark);

GST_API

gpointer        gst_mini_object_steal_qdata     (GstMiniObject *object, GQuark quark);

GST_API

gboolean        gst_mini_object_replace         (GstMiniObject **olddata, GstMiniObject *newdata);

GST_API

gboolean        gst_mini_object_take            (GstMiniObject **olddata, GstMiniObject *newdata);

GST_API

GstMiniObject * gst_mini_object_steal           (GstMiniObject **olddata) G_GNUC_WARN_UNUSED_RESULT;

/**

 * GST_DEFINE_MINI_OBJECT_TYPE:

 * @TypeName: name of the new type in CamelCase

 * @type_name: name of the new type

 *

 * Define a new mini-object type with the given name

 */

#define GST_DEFINE_MINI_OBJECT_TYPE(TypeName,type_name) \

   G_DEFINE_BOXED_TYPE(TypeName,type_name,              \

       (GBoxedCopyFunc) gst_mini_object_ref,            \

       (GBoxedFreeFunc) gst_mini_object_unref)

G_END_DECLS

#endif