2 * Copyright (C) 2009 Axis Communications <dev-gstreamer at axis dot com>
3 * @author Jonas Holmberg <jonas dot holmberg at axis dot com>
5 * gstbufferlist.c: Buffer list
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.
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.
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., 59 Temple Place - Suite 330,
20 * Boston, MA 02111-1307, USA.
24 * SECTION:gstbufferlist
25 * @short_description: Lists of buffers for data-passing
26 * @see_also: #GstPad, #GstMiniObject
28 * Buffer lists are an object containing a list of buffers.
30 * Buffer lists are created with gst_buffer_list_new() and filled with data
31 * using a gst_buffer_list_insert().
33 * Buffer lists can be pushed on a srcpad with gst_pad_push_list(). This is
34 * interesting when multiple buffers need to be pushed in one go because it
35 * can reduce the amount of overhead for pushing each buffer individually.
37 * Last reviewed on 2012-03-28 (0.11.3)
39 #include "gst_private.h"
41 #include "gstbuffer.h"
42 #include "gstbufferlist.h"
44 #define GST_CAT_DEFAULT GST_CAT_BUFFER_LIST
49 * Opaque list of grouped buffers.
55 GstMiniObject mini_object;
60 GType _gst_buffer_list_type = 0;
62 GST_DEFINE_MINI_OBJECT_TYPE (GstBufferList, gst_buffer_list);
65 _priv_gst_buffer_list_initialize (void)
67 _gst_buffer_list_type = gst_buffer_list_get_type ();
70 static GstBufferList *
71 _gst_buffer_list_copy (GstBufferList * list)
76 len = list->array->len;
77 copy = gst_buffer_list_new_sized (len);
79 /* add and ref all buffers in the array */
80 for (i = 0; i < len; i++) {
81 GstBuffer *buf = g_array_index (list->array, GstBuffer *, i);
82 buf = gst_buffer_ref (buf);
83 g_array_append_val (copy->array, buf);
89 _gst_buffer_list_free (GstBufferList * list)
92 GST_LOG ("free %p", list);
94 /* unrefs all buffers too */
95 len = list->array->len;
96 for (i = 0; i < len; i++)
97 gst_buffer_unref (g_array_index (list->array, GstBuffer *, i));
98 g_array_free (list->array, TRUE);
100 g_slice_free1 (GST_MINI_OBJECT_SIZE (list), list);
104 gst_buffer_list_init (GstBufferList * list, gsize size, guint asize)
106 gst_mini_object_init (GST_MINI_OBJECT_CAST (list), _gst_buffer_list_type,
109 list->mini_object.copy = (GstMiniObjectCopyFunction) _gst_buffer_list_copy;
110 list->mini_object.free = (GstMiniObjectFreeFunction) _gst_buffer_list_free;
112 list->array = g_array_sized_new (FALSE, FALSE, sizeof (GstBuffer *), asize);
114 GST_LOG ("init %p", list);
118 * gst_buffer_list_new_sized:
119 * @size: an initial reserved size
121 * Creates a new, empty #GstBufferList. The caller is responsible for unreffing
122 * the returned #GstBufferList. The list will have @size space preallocated so
123 * that memory reallocations can be avoided.
125 * Free-function: gst_buffer_list_unref
127 * Returns: (transfer full): the new #GstBufferList. gst_buffer_list_unref()
133 gst_buffer_list_new_sized (guint size)
137 list = g_slice_new0 (GstBufferList);
139 GST_LOG ("new %p", list);
141 gst_buffer_list_init (list, sizeof (GstBufferList), size);
147 * gst_buffer_list_new:
149 * Creates a new, empty #GstBufferList. The caller is responsible for unreffing
150 * the returned #GstBufferList.
152 * Free-function: gst_buffer_list_unref
154 * Returns: (transfer full): the new #GstBufferList. gst_buffer_list_unref()
160 gst_buffer_list_new (void)
162 return gst_buffer_list_new_sized (8);
166 * gst_buffer_list_length:
167 * @list: a #GstBufferList
169 * Returns the number of buffers in @list.
171 * Returns: the number of buffers in the buffer list
176 gst_buffer_list_length (GstBufferList * list)
178 g_return_val_if_fail (GST_IS_BUFFER_LIST (list), 0);
180 return list->array->len;
184 * gst_buffer_list_foreach:
185 * @list: a #GstBufferList
186 * @func: (scope call): a #GstBufferListFunc to call
187 * @user_data: (closure): user data passed to @func
189 * Call @func with @data for each buffer in @list.
191 * @func can modify the passed buffer pointer or its contents. The return value
192 * of @func define if this function returns or if the remaining buffers in
193 * the list should be skipped.
198 gst_buffer_list_foreach (GstBufferList * list, GstBufferListFunc func,
203 g_return_if_fail (GST_IS_BUFFER_LIST (list));
204 g_return_if_fail (func != NULL);
206 len = list->array->len;
207 for (i = 0; i < len;) {
208 GstBuffer *buf, *buf_ret;
211 buf = buf_ret = g_array_index (list->array, GstBuffer *, i);
212 ret = func (&buf_ret, i, user_data);
214 /* Check if the function changed the buffer */
215 if (buf != buf_ret) {
216 if (buf_ret == NULL) {
217 g_array_remove_index (list->array, i);
220 g_array_index (list->array, GstBuffer *, i) = buf_ret;
227 /* If the buffer was not removed by func go to the next buffer */
234 * gst_buffer_list_get:
235 * @list: a #GstBufferList
238 * Get the buffer at @idx.
240 * Returns: (transfer none): the buffer at @idx in @group or NULL when there
241 * is no buffer. The buffer remains valid as long as @list is valid.
246 gst_buffer_list_get (GstBufferList * list, guint idx)
250 g_return_val_if_fail (GST_IS_BUFFER_LIST (list), NULL);
251 g_return_val_if_fail (idx < list->array->len, NULL);
253 buf = g_array_index (list->array, GstBuffer *, idx);
259 * gst_buffer_list_insert:
260 * @list: a #GstBufferList
262 * @buffer: a #GstBuffer
264 * Insert @buffer at @idx in @list. Other buffers are moved to make room for
267 * A -1 value for @idx will append the buffer at the end.
270 gst_buffer_list_insert (GstBufferList * list, guint idx, GstBuffer * buffer)
272 g_return_if_fail (GST_IS_BUFFER_LIST (list));
273 g_return_if_fail (buffer != NULL);
276 g_array_append_val (list->array, buffer);
278 g_return_if_fail (idx < list->array->len);
279 g_array_insert_val (list->array, idx, buffer);
284 * gst_buffer_list_remove:
285 * @list: a #GstBufferList
287 * @length: the amount to remove
289 * Remove @length buffers starting from @idx in @list. The following buffers are
290 * moved to close the gap.
293 gst_buffer_list_remove (GstBufferList * list, guint idx, guint length)
295 g_return_if_fail (GST_IS_BUFFER_LIST (list));
296 g_return_if_fail (idx < list->array->len);
298 g_array_remove_range (list->array, idx, length);