gstreamer/gst/gstbufferlist.h
Jeffrey S. Smith 4375e998ee Fix casts in a bunch of inline functions to maintain correct const-ness
Make code including GStreamer headers compile with -Wcast-qual by
maintaining const-ness when casting. Also fix function signature of
gst_byte_writer_set_pos(): the byte writer should not be marked as
const.

https://bugzilla.gnome.org/show_bug.cgi?id=627910
2010-09-02 00:09:08 +01:00

236 lines
8.5 KiB
C

/* GStreamer
* Copyright (C) 2009 Axis Communications <dev-gstreamer at axis dot com>
* @author Jonas Holmberg <jonas dot holmberg at axis dot com>
*
* gstbufferlist.h: Header for GstBufferList object
*
* 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_BUFFER_LIST_H__
#define __GST_BUFFER_LIST_H__
#include <gst/gstbuffer.h>
G_BEGIN_DECLS
#define GST_TYPE_BUFFER_LIST (gst_buffer_list_get_type ())
#define GST_IS_BUFFER_LIST(obj) (G_TYPE_CHECK_INSTANCE_TYPE ((obj), GST_TYPE_BUFFER_LIST))
#define GST_IS_BUFFER_LIST_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE ((klass), GST_TYPE_BUFFER_LIST))
#define GST_BUFFER_LIST_GET_CLASS(obj) (G_TYPE_INSTANCE_GET_CLASS ((obj), GST_TYPE_BUFFER_LIST, GstBufferListClass))
#define GST_BUFFER_LIST(obj) (G_TYPE_CHECK_INSTANCE_CAST ((obj), GST_TYPE_BUFFER_LIST, GstBufferList))
#define GST_BUFFER_LIST_CLASS(klass) (G_TYPE_CHECK_CLASS_CAST ((klass), GST_TYPE_BUFFER_LIST, GstBufferListClass))
#define GST_BUFFER_LIST_CAST(obj) ((GstBufferList *)obj)
typedef struct _GstBufferList GstBufferList;
typedef struct _GstBufferListClass GstBufferListClass;
typedef struct _GstBufferListIterator GstBufferListIterator;
/**
* GstBufferListDoFunction:
* @buffer: the #GstBuffer
* @user_data: user data
*
* A function for accessing the last buffer returned by
* gst_buffer_list_iterator_next(). The function can leave @buffer in the list,
* replace @buffer in the list or remove @buffer from the list, depending on
* the return value. If the function returns NULL, @buffer will be removed from
* the list, otherwise @buffer will be replaced with the returned buffer.
*
* The last buffer returned by gst_buffer_list_iterator_next() will be replaced
* with the buffer returned from the function. The function takes ownership of
* @buffer and if a different value than @buffer is returned, @buffer must be
* unreffed. If NULL is returned, the buffer will be removed from the list. The
* list must be writable.
*
* Returns: the buffer to replace @buffer in the list, or NULL to remove @buffer
* from the list
*
* Since: 0.10.24
*/
typedef GstBuffer* (*GstBufferListDoFunction) (GstBuffer * buffer, gpointer user_data);
/**
* GstBufferListItem:
* @GST_BUFFER_LIST_CONTINUE: Retrieve next buffer
* @GST_BUFFER_LIST_SKIP_GROUP: Skip to next group
* @GST_BUFFER_LIST_END: End iteration
*
* The result of the #GstBufferListFunc.
*
* Since: 0.10.24
*/
typedef enum {
GST_BUFFER_LIST_CONTINUE,
GST_BUFFER_LIST_SKIP_GROUP,
GST_BUFFER_LIST_END
} GstBufferListItem;
/**
* GstBufferListFunc:
* @buffer: pointer the buffer
* @group: the group index of @buffer
* @idx: the index in @group of @buffer
* @user_data: user data passed to gst_buffer_list_foreach()
*
* A function that will be called from gst_buffer_list_foreach(). The @buffer
* field will point to a the reference of the buffer at @idx in @group.
*
* When this function returns #GST_BUFFER_LIST_CONTINUE, the next buffer will be
* returned. When #GST_BUFFER_LIST_SKIP_GROUP is returned, all remaining buffers
* in the current group will be skipped and the first buffer of the next group
* is returned (if any). When GST_BUFFER_LIST_END is returned,
* gst_buffer_list_foreach() will return.
*
* When @buffer is set to NULL, the item will be removed from the bufferlist.
* When @buffer has been made writable, the new buffer reference can be assigned
* to @buffer. This function is responsible for unreffing the old buffer when
* removing or modifying.
*
* Returns: a #GstBufferListItem
*
* Since: 0.10.24
*/
typedef GstBufferListItem (*GstBufferListFunc) (GstBuffer **buffer, guint group, guint idx,
gpointer user_data);
GType gst_buffer_list_get_type (void);
/* allocation */
GstBufferList *gst_buffer_list_new (void);
/* refcounting */
/**
* gst_buffer_list_ref:
* @list: a #GstBufferList
*
* Increases the refcount of the given buffer list by one.
*
* Note that the refcount affects the writeability of @list and its data, see
* gst_buffer_list_make_writable(). It is important to note that keeping
* additional references to GstBufferList instances can potentially increase
* the number of memcpy operations in a pipeline.
*
* Returns: @list
*
* Since: 0.10.24
*/
#ifdef _FOOL_GTK_DOC_
G_INLINE_FUNC GstBufferList * gst_buffer_list_ref (GstBufferList * list);
#endif
static inline GstBufferList *
gst_buffer_list_ref (GstBufferList * list)
{
return GST_BUFFER_LIST_CAST (gst_mini_object_ref (GST_MINI_OBJECT_CAST (
list)));
}
/**
* gst_buffer_list_unref:
* @list: a #GstBufferList
*
* Decreases the refcount of the buffer list. If the refcount reaches 0, the
* buffer list will be freed.
*
* Since: 0.10.24
*/
#ifdef _FOOL_GTK_DOC_
G_INLINE_FUNC void gst_buffer_list_unref (GstBufferList * list);
#endif
static inline void
gst_buffer_list_unref (GstBufferList * list)
{
gst_mini_object_unref (GST_MINI_OBJECT_CAST (list));
}
/* copy */
/**
* gst_buffer_list_copy:
* @list: a #GstBufferList
*
* Create a shallow copy of the given buffer list. This will make a newly
* allocated copy of the source list with copies of buffer pointers. The
* refcount of buffers pointed to will be increased by one.
*
* Returns: a new copy of @list.
*
* Since: 0.10.24
*/
#ifdef _FOOL_GTK_DOC_
G_INLINE_FUNC GstBufferList * gst_buffer_list_copy (const GstBufferList * list);
#endif
static inline GstBufferList *
gst_buffer_list_copy (const GstBufferList * list)
{
return GST_BUFFER_LIST_CAST (gst_mini_object_copy (GST_MINI_OBJECT_CONST_CAST (list)));
}
/**
* gst_buffer_list_is_writable:
* @list: a #GstBufferList
*
* Tests if you can safely add buffers and groups into a buffer list.
*
* Since: 0.10.24
*/
#define gst_buffer_list_is_writable(list) gst_mini_object_is_writable (GST_MINI_OBJECT_CAST (list))
/**
* gst_buffer_list_make_writable:
* @list: a #GstBufferList
*
* Makes a writable buffer list from the given buffer list. If the source buffer
* list is already writable, this will simply return the same buffer list. A
* copy will otherwise be made using gst_buffer_list_copy().
*
* Since: 0.10.24
*/
#define gst_buffer_list_make_writable(list) GST_BUFFER_LIST_CAST (gst_mini_object_make_writable (GST_MINI_OBJECT_CAST (list)))
guint gst_buffer_list_n_groups (GstBufferList *list);
void gst_buffer_list_foreach (GstBufferList *list,
GstBufferListFunc func,
gpointer user_data);
GstBuffer * gst_buffer_list_get (GstBufferList *list, guint group, guint idx);
/* iterator */
GstBufferListIterator * gst_buffer_list_iterate (GstBufferList *list);
void gst_buffer_list_iterator_free (GstBufferListIterator *it);
guint gst_buffer_list_iterator_n_buffers (const GstBufferListIterator *it);
GstBuffer * gst_buffer_list_iterator_next (GstBufferListIterator *it);
gboolean gst_buffer_list_iterator_next_group (GstBufferListIterator *it);
void gst_buffer_list_iterator_add (GstBufferListIterator *it, GstBuffer *buffer);
void gst_buffer_list_iterator_add_group (GstBufferListIterator *it);
void gst_buffer_list_iterator_remove (GstBufferListIterator *it);
GstBuffer * gst_buffer_list_iterator_steal (GstBufferListIterator *it);
void gst_buffer_list_iterator_take (GstBufferListIterator *it, GstBuffer *buffer);
GstBuffer * gst_buffer_list_iterator_do (GstBufferListIterator *it, GstBufferListDoFunction do_func,
gpointer user_data);
/* conversion */
GstBuffer * gst_buffer_list_iterator_merge_group (const GstBufferListIterator *it);
G_END_DECLS
#endif /* __GST_BUFFER_LIST_H__ */