1/* GStreamer
2 * Copyright (C) 2009 Axis Communications <dev-gstreamer at axis dot com>
3 * @author Jonas Holmberg <jonas dot holmberg at axis dot com>
4 *
5 * gstbufferlist.h: Header for GstBufferList object
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., 51 Franklin St, Fifth Floor,
20 * Boston, MA 02110-1301, USA.
21 */
22
23#ifndef __GST_BUFFER_LIST_H__
24#define __GST_BUFFER_LIST_H__
25
26#include <gst/gstbuffer.h>
27
28G_BEGIN_DECLS
29
30GST_API GType _gst_buffer_list_type;
31
32#define GST_TYPE_BUFFER_LIST (_gst_buffer_list_type)
33#define GST_IS_BUFFER_LIST(obj) (GST_IS_MINI_OBJECT_TYPE(obj, GST_TYPE_BUFFER_LIST))
34#define GST_BUFFER_LIST_CAST(obj) ((GstBufferList *)obj)
35#define GST_BUFFER_LIST(obj) (GST_BUFFER_LIST_CAST(obj))
36
37typedef struct _GstBufferList GstBufferList;
38
39/**
40 * GstBufferListFunc:
41 * @buffer: (out) (nullable): pointer the buffer
42 * @idx: the index of @buffer
43 * @user_data: user data passed to gst_buffer_list_foreach()
44 *
45 * A function that will be called from gst_buffer_list_foreach(). The @buffer
46 * field will point to a the reference of the buffer at @idx.
47 *
48 * When this function returns %TRUE, the next buffer will be
49 * returned. When %FALSE is returned, gst_buffer_list_foreach() will return.
50 *
51 * When @buffer is set to %NULL, the item will be removed from the bufferlist.
52 * When @buffer has been made writable, the new buffer reference can be assigned
53 * to @buffer. This function is responsible for unreffing the old buffer when
54 * removing or modifying.
55 *
56 * Returns: %FALSE when gst_buffer_list_foreach() should stop
57 */
58typedef gboolean (*GstBufferListFunc) (GstBuffer **buffer, guint idx,
59 gpointer user_data);
60
61
62/* refcounting */
63/**
64 * gst_buffer_list_ref:
65 * @list: a #GstBufferList
66 *
67 * Increases the refcount of the given buffer list by one.
68 *
69 * Note that the refcount affects the writability of @list and its data, see
70 * gst_buffer_list_make_writable(). It is important to note that keeping
71 * additional references to GstBufferList instances can potentially increase
72 * the number of memcpy operations in a pipeline.
73 *
74 * Returns: (transfer full): @list
75 */
76static inline GstBufferList *
77gst_buffer_list_ref (GstBufferList * list)
78{
79 return GST_BUFFER_LIST_CAST (gst_mini_object_ref (GST_MINI_OBJECT_CAST (
80 list)));
81}
82
83/**
84 * gst_buffer_list_unref:
85 * @list: (transfer full): a #GstBufferList
86 *
87 * Decreases the refcount of the buffer list. If the refcount reaches 0, the
88 * buffer list will be freed.
89 */
90static inline void
91gst_buffer_list_unref (GstBufferList * list)
92{
93 gst_mini_object_unref (GST_MINI_OBJECT_CAST (list));
94}
95
96/**
97 * gst_clear_buffer_list: (skip)
98 * @list_ptr: a pointer to a #GstBufferList reference
99 *
100 * Clears a reference to a #GstBufferList.
101 *
102 * @list_ptr must not be %NULL.
103 *
104 * If the reference is %NULL then this function does nothing. Otherwise, the
105 * reference count of the list is decreased and the pointer is set to %NULL.
106 *
107 * Since: 1.16
108 */
109static inline void
110gst_clear_buffer_list (GstBufferList ** list_ptr)
111{
112 gst_clear_mini_object ((GstMiniObject **) list_ptr);
113}
114
115/* copy */
116/**
117 * gst_buffer_list_copy:
118 * @list: a #GstBufferList
119 *
120 * Create a shallow copy of the given buffer list. This will make a newly
121 * allocated copy of the source list with copies of buffer pointers. The
122 * refcount of buffers pointed to will be increased by one.
123 *
124 * Returns: (transfer full): a new copy of @list.
125 */
126static inline GstBufferList *
127gst_buffer_list_copy (const GstBufferList * list)
128{
129 return GST_BUFFER_LIST_CAST (gst_mini_object_copy (GST_MINI_OBJECT_CONST_CAST (list)));
130}
131
132/**
133 * gst_buffer_list_replace:
134 * @old_list: (inout) (transfer full) (nullable): pointer to a pointer to a
135 * #GstBufferList to be replaced.
136 * @new_list: (transfer none) (allow-none): pointer to a #GstBufferList that
137 * will replace the buffer list pointed to by @old_list.
138 *
139 * Modifies a pointer to a #GstBufferList to point to a different
140 * #GstBufferList. The modification is done atomically (so this is useful for
141 * ensuring thread safety in some cases), and the reference counts are updated
142 * appropriately (the old buffer list is unreffed, the new is reffed).
143 *
144 * Either @new_list or the #GstBufferList pointed to by @old_list may be %NULL.
145 *
146 * Returns: %TRUE if @new_list was different from @old_list
147 *
148 * Since: 1.16
149 */
150static inline gboolean
151gst_buffer_list_replace (GstBufferList **old_list, GstBufferList *new_list)
152{
153 return gst_mini_object_replace ((GstMiniObject **) old_list,
154 (GstMiniObject *) new_list);
155}
156
157/**
158 * gst_buffer_list_take:
159 * @old_list: (inout) (transfer full): pointer to a pointer to a #GstBufferList
160 * to be replaced.
161 * @new_list: (transfer full) (allow-none): pointer to a #GstBufferList
162 * that will replace the bufferlist pointed to by @old_list.
163 *
164 * Modifies a pointer to a #GstBufferList to point to a different
165 * #GstBufferList. This function is similar to gst_buffer_list_replace() except
166 * that it takes ownership of @new_list.
167 *
168 * Returns: %TRUE if @new_list was different from @old_list
169 *
170 * Since: 1.16
171 */
172static inline gboolean
173gst_buffer_list_take (GstBufferList **old_list, GstBufferList *new_list)
174{
175 return gst_mini_object_take ((GstMiniObject **) old_list,
176 (GstMiniObject *) new_list);
177}
178
179/**
180 * gst_buffer_list_is_writable:
181 * @list: a #GstBufferList
182 *
183 * Tests if you can safely add buffers and groups into a buffer list.
184 */
185#define gst_buffer_list_is_writable(list) gst_mini_object_is_writable (GST_MINI_OBJECT_CAST (list))
186
187/**
188 * gst_buffer_list_make_writable:
189 * @list: (transfer full): a #GstBufferList
190 *
191 * Makes a writable buffer list from the given buffer list. If the source buffer
192 * list is already writable, this will simply return the same buffer list. A
193 * copy will otherwise be made using gst_buffer_list_copy().
194 *
195 * Returns: (transfer full): a writable list, which may or may not be the
196 * same as @list
197 */
198#define gst_buffer_list_make_writable(list) GST_BUFFER_LIST_CAST (gst_mini_object_make_writable (GST_MINI_OBJECT_CAST (list)))
199
200GST_API
201GType gst_buffer_list_get_type (void);
202
203/* allocation */
204
205GST_API
206GstBufferList * gst_buffer_list_new (void) G_GNUC_MALLOC;
207
208GST_API
209GstBufferList * gst_buffer_list_new_sized (guint size) G_GNUC_MALLOC;
210
211GST_API
212guint gst_buffer_list_length (GstBufferList *list);
213
214GST_API
215GstBuffer * gst_buffer_list_get (GstBufferList *list, guint idx);
216
217GST_API
218GstBuffer * gst_buffer_list_get_writable (GstBufferList *list, guint idx);
219
220GST_API
221void gst_buffer_list_insert (GstBufferList *list, gint idx, GstBuffer *buffer);
222
223GST_API
224void gst_buffer_list_remove (GstBufferList *list, guint idx, guint length);
225
226GST_API
227gboolean gst_buffer_list_foreach (GstBufferList *list,
228 GstBufferListFunc func,
229 gpointer user_data);
230GST_API
231GstBufferList * gst_buffer_list_copy_deep (const GstBufferList * list);
232
233GST_API
234gsize gst_buffer_list_calculate_size (GstBufferList * list);
235
236#define gst_buffer_list_add(l,b) gst_buffer_list_insert((l),-1,(b));
237
238#ifdef G_DEFINE_AUTOPTR_CLEANUP_FUNC
239G_DEFINE_AUTOPTR_CLEANUP_FUNC(GstBufferList, gst_buffer_list_unref)
240#endif
241
242G_END_DECLS
243
244#endif /* __GST_BUFFER_LIST_H__ */
245