2 * Copyright (C) 1999,2000 Erik Walthinsen <omega@cse.ogi.edu>
3 * 2000 Wim Taymans <wtay@chello.be>
5 * gstbuffer.c: Buffer operations
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., 51 Franklin St, Fifth Floor,
20 * Boston, MA 02110-1301, USA.
25 * @short_description: Data-passing buffer type
26 * @see_also: #GstPad, #GstMiniObject, #GstMemory, #GstMeta, #GstBufferPool
28 * Buffers are the basic unit of data transfer in GStreamer. They contain the
29 * timing and offset along with other arbitrary metadata that is associated
30 * with the #GstMemory blocks that the buffer contains.
32 * Buffers are usually created with gst_buffer_new(). After a buffer has been
33 * created one will typically allocate memory for it and add it to the buffer.
34 * The following example creates a buffer that can hold a given video frame
35 * with a given width, height and bits per plane.
39 * gint size, width, height, bpp;
41 * size = width * height * bpp;
42 * buffer = gst_buffer_new ();
43 * memory = gst_allocator_alloc (NULL, size, NULL);
44 * gst_buffer_insert_memory (buffer, -1, memory);
48 * Alternatively, use gst_buffer_new_allocate() to create a buffer with
49 * preallocated data of a given size.
51 * Buffers can contain a list of #GstMemory objects. You can retrieve how many
52 * memory objects with gst_buffer_n_memory() and you can get a pointer
53 * to memory with gst_buffer_peek_memory()
55 * A buffer will usually have timestamps, and a duration, but neither of these
56 * are guaranteed (they may be set to #GST_CLOCK_TIME_NONE). Whenever a
57 * meaningful value can be given for these, they should be set. The timestamps
58 * and duration are measured in nanoseconds (they are #GstClockTime values).
60 * The buffer DTS refers to the timestamp when the buffer should be decoded and
61 * is usually monotonically increasing. The buffer PTS refers to the timestamp when
62 * the buffer content should be presented to the user and is not always
63 * monotonically increasing.
65 * A buffer can also have one or both of a start and an end offset. These are
66 * media-type specific. For video buffers, the start offset will generally be
67 * the frame number. For audio buffers, it will be the number of samples
68 * produced so far. For compressed data, it could be the byte offset in a
69 * source or destination file. Likewise, the end offset will be the offset of
70 * the end of the buffer. These can only be meaningfully interpreted if you
71 * know the media type of the buffer (the preceding CAPS event). Either or both
72 * can be set to #GST_BUFFER_OFFSET_NONE.
74 * gst_buffer_ref() is used to increase the refcount of a buffer. This must be
75 * done when you want to keep a handle to the buffer after pushing it to the
76 * next element. The buffer refcount determines the writability of the buffer, a
77 * buffer is only writable when the refcount is exactly 1, i.e. when the caller
78 * has the only reference to the buffer.
80 * To efficiently create a smaller buffer out of an existing one, you can
81 * use gst_buffer_copy_region(). This method tries to share the memory objects
82 * between the two buffers.
84 * If a plug-in wants to modify the buffer data or metadata in-place, it should
85 * first obtain a buffer that is safe to modify by using
86 * gst_buffer_make_writable(). This function is optimized so that a copy will
87 * only be made when it is necessary.
89 * Several flags of the buffer can be set and unset with the
90 * GST_BUFFER_FLAG_SET() and GST_BUFFER_FLAG_UNSET() macros. Use
91 * GST_BUFFER_FLAG_IS_SET() to test if a certain #GstBufferFlags flag is set.
93 * Buffers can be efficiently merged into a larger buffer with
94 * gst_buffer_append(). Copying of memory will only be done when absolutely
97 * Arbitrary extra metadata can be set on a buffer with gst_buffer_add_meta().
98 * Metadata can be retrieved with gst_buffer_get_meta(). See also #GstMeta
100 * An element should either unref the buffer or push it out on a src pad
101 * using gst_pad_push() (see #GstPad).
103 * Buffers are usually freed by unreffing them with gst_buffer_unref(). When
104 * the refcount drops to 0, any memory and metadata pointed to by the buffer is
105 * unreffed as well. Buffers allocated from a #GstBufferPool will be returned to
106 * the pool when the refcount drops to 0.
108 * The #GstParentBufferMeta is a meta which can be attached to a #GstBuffer
109 * to hold a reference to another buffer that is only released when the child
110 * #GstBuffer is released.
112 * Typically, #GstParentBufferMeta is used when the child buffer is directly
113 * using the #GstMemory of the parent buffer, and wants to prevent the parent
114 * buffer from being returned to a buffer pool until the #GstMemory is available
115 * for re-use. (Since 1.6)
118 #include "gst_private.h"
127 #include "gstbuffer.h"
128 #include "gstbufferpool.h"
130 #include "gstutils.h"
131 #include "gstversion.h"
133 GType _gst_buffer_type = 0;
135 typedef struct _GstMetaItem GstMetaItem;
142 #define ITEM_SIZE(info) ((info)->size + sizeof (GstMetaItem))
144 #define GST_BUFFER_MEM_MAX 16
146 #define GST_BUFFER_SLICE_SIZE(b) (((GstBufferImpl *)(b))->slice_size)
147 #define GST_BUFFER_MEM_LEN(b) (((GstBufferImpl *)(b))->len)
148 #define GST_BUFFER_MEM_ARRAY(b) (((GstBufferImpl *)(b))->mem)
149 #define GST_BUFFER_MEM_PTR(b,i) (((GstBufferImpl *)(b))->mem[i])
150 #define GST_BUFFER_BUFMEM(b) (((GstBufferImpl *)(b))->bufmem)
151 #define GST_BUFFER_META(b) (((GstBufferImpl *)(b))->item)
159 /* the memory blocks */
161 GstMemory *mem[GST_BUFFER_MEM_MAX];
163 /* memory of the buffer when allocated from 1 chunk */
166 /* FIXME, make metadata allocation more efficient by using part of the
173 _is_span (GstMemory ** mem, gsize len, gsize * poffset, GstMemory ** parent)
175 GstMemory *mcur, *mprv;
176 gboolean have_offset = FALSE;
181 for (i = 0; i < len; i++) {
189 /* check if memory is contiguous */
190 if (!gst_memory_is_span (mprv, mcur, &poffs))
197 *parent = mprv->parent;
207 _get_merged_memory (GstBuffer * buffer, guint idx, guint length)
209 GstMemory **mem, *result = NULL;
211 GST_CAT_LOG (GST_CAT_BUFFER, "buffer %p, idx %u, length %u", buffer, idx,
214 mem = GST_BUFFER_MEM_ARRAY (buffer);
216 if (G_UNLIKELY (length == 0)) {
218 } else if (G_LIKELY (length == 1)) {
219 result = gst_memory_ref (mem[idx]);
221 GstMemory *parent = NULL;
222 gsize size, poffset = 0;
224 size = gst_buffer_get_sizes_range (buffer, idx, length, NULL, NULL);
226 if (G_UNLIKELY (_is_span (mem + idx, length, &poffset, &parent))) {
227 if (!GST_MEMORY_IS_NO_SHARE (parent))
228 result = gst_memory_share (parent, poffset, size);
230 GST_CAT_DEBUG (GST_CAT_PERFORMANCE, "copy for merge %p", parent);
231 result = gst_memory_copy (parent, poffset, size);
234 gsize i, tocopy, left;
235 GstMapInfo sinfo, dinfo;
238 result = gst_allocator_alloc (NULL, size, NULL);
239 gst_memory_map (result, &dinfo, GST_MAP_WRITE);
244 for (i = idx; i < (idx + length) && left > 0; i++) {
245 gst_memory_map (mem[i], &sinfo, GST_MAP_READ);
246 tocopy = MIN (sinfo.size, left);
247 GST_CAT_DEBUG (GST_CAT_PERFORMANCE,
248 "memcpy %" G_GSIZE_FORMAT " bytes for merge %p from memory %p",
249 tocopy, result, mem[i]);
250 memcpy (ptr, (guint8 *) sinfo.data, tocopy);
253 gst_memory_unmap (mem[i], &sinfo);
255 gst_memory_unmap (result, &dinfo);
262 _replace_memory (GstBuffer * buffer, guint len, guint idx, guint length,
269 GST_CAT_LOG (GST_CAT_BUFFER,
270 "buffer %p replace %u-%" G_GSIZE_FORMAT " with memory %p", buffer, idx,
273 /* unref old memory */
274 for (i = idx; i < end; i++) {
275 GstMemory *old = GST_BUFFER_MEM_PTR (buffer, i);
277 gst_memory_unlock (old, GST_LOCK_FLAG_EXCLUSIVE);
278 gst_memory_unref (old);
282 /* replace with single memory */
283 gst_memory_lock (mem, GST_LOCK_FLAG_EXCLUSIVE);
284 GST_BUFFER_MEM_PTR (buffer, idx) = mem;
290 memmove (&GST_BUFFER_MEM_PTR (buffer, idx),
291 &GST_BUFFER_MEM_PTR (buffer, end), (len - end) * sizeof (gpointer));
293 GST_BUFFER_MEM_LEN (buffer) = len - length;
294 GST_BUFFER_FLAG_SET (buffer, GST_BUFFER_FLAG_TAG_MEMORY);
297 /* transfer full for return and transfer none for @mem */
298 static inline GstMemory *
299 _memory_get_exclusive_reference (GstMemory * mem)
301 GstMemory *ret = NULL;
303 if (gst_memory_lock (mem, GST_LOCK_FLAG_EXCLUSIVE)) {
304 ret = gst_memory_ref (mem);
306 /* we cannot take another exclusive lock as the memory is already
307 * locked WRITE + EXCLUSIVE according to part-miniobject.txt */
308 ret = gst_memory_copy (mem, 0, -1);
311 if (!gst_memory_lock (ret, GST_LOCK_FLAG_EXCLUSIVE)) {
312 gst_memory_unref (ret);
319 GST_CAT_WARNING (GST_CAT_BUFFER, "Failed to acquire an exclusive lock for "
326 _memory_add (GstBuffer * buffer, gint idx, GstMemory * mem)
328 guint i, len = GST_BUFFER_MEM_LEN (buffer);
330 GST_CAT_LOG (GST_CAT_BUFFER, "buffer %p, idx %d, mem %p", buffer, idx, mem);
332 if (G_UNLIKELY (len >= GST_BUFFER_MEM_MAX)) {
333 /* too many buffer, span them. */
334 /* FIXME, there is room for improvement here: We could only try to merge
335 * 2 buffers to make some room. If we can't efficiently merge 2 buffers we
336 * could try to only merge the two smallest buffers to avoid memcpy, etc. */
337 GST_CAT_DEBUG (GST_CAT_PERFORMANCE, "memory array overflow in buffer %p",
339 _replace_memory (buffer, len, 0, len, _get_merged_memory (buffer, 0, len));
340 /* we now have 1 single spanned buffer */
347 for (i = len; i > idx; i--) {
348 /* move buffers to insert, FIXME, we need to insert first and then merge */
349 GST_BUFFER_MEM_PTR (buffer, i) = GST_BUFFER_MEM_PTR (buffer, i - 1);
351 /* and insert the new buffer */
352 GST_BUFFER_MEM_PTR (buffer, idx) = mem;
353 GST_BUFFER_MEM_LEN (buffer) = len + 1;
355 GST_BUFFER_FLAG_SET (buffer, GST_BUFFER_FLAG_TAG_MEMORY);
358 GST_DEFINE_MINI_OBJECT_TYPE (GstBuffer, gst_buffer);
361 _priv_gst_buffer_initialize (void)
363 _gst_buffer_type = gst_buffer_get_type ();
367 * gst_buffer_get_max_memory:
369 * Get the maximum amount of memory blocks that a buffer can hold. This is a
370 * compile time constant that can be queried with the function.
372 * When more memory blocks are added, existing memory blocks will be merged
373 * together to make room for the new block.
375 * Returns: the maximum amount of memory blocks that a buffer can hold.
380 gst_buffer_get_max_memory (void)
382 return GST_BUFFER_MEM_MAX;
386 * gst_buffer_copy_into:
387 * @dest: a destination #GstBuffer
388 * @src: a source #GstBuffer
389 * @flags: flags indicating what metadata fields should be copied.
390 * @offset: offset to copy from
391 * @size: total size to copy. If -1, all data is copied.
393 * Copies the information from @src into @dest.
395 * If @dest already contains memory and @flags contains GST_BUFFER_COPY_MEMORY,
396 * the memory from @src will be appended to @dest.
398 * @flags indicate which fields will be copied.
400 * Returns: %TRUE if the copying succeeded, %FALSE otherwise.
403 gst_buffer_copy_into (GstBuffer * dest, GstBuffer * src,
404 GstBufferCopyFlags flags, gsize offset, gsize size)
408 gboolean region = FALSE;
409 gboolean shared_memory;
411 g_return_val_if_fail (dest != NULL, FALSE);
412 g_return_val_if_fail (src != NULL, FALSE);
414 /* nothing to copy if the buffers are the same */
415 if (G_UNLIKELY (dest == src))
418 g_return_val_if_fail (gst_buffer_is_writable (dest), FALSE);
420 bufsize = gst_buffer_get_size (src);
421 g_return_val_if_fail (bufsize >= offset, FALSE);
425 size = bufsize - offset;
428 g_return_val_if_fail (bufsize >= offset + size, FALSE);
430 GST_CAT_LOG (GST_CAT_BUFFER, "copy %p to %p, offset %" G_GSIZE_FORMAT
431 "-%" G_GSIZE_FORMAT "/%" G_GSIZE_FORMAT, src, dest, offset, size,
434 if (flags & GST_BUFFER_COPY_FLAGS) {
436 guint flags_mask = ~GST_BUFFER_FLAG_TAG_MEMORY;
438 GST_MINI_OBJECT_FLAGS (dest) =
439 (GST_MINI_OBJECT_FLAGS (src) & flags_mask) |
440 (GST_MINI_OBJECT_FLAGS (dest) & ~flags_mask);
443 if (flags & GST_BUFFER_COPY_TIMESTAMPS) {
445 GST_BUFFER_PTS (dest) = GST_BUFFER_PTS (src);
446 GST_BUFFER_DTS (dest) = GST_BUFFER_DTS (src);
447 GST_BUFFER_OFFSET (dest) = GST_BUFFER_OFFSET (src);
448 if (size == bufsize) {
449 GST_BUFFER_DURATION (dest) = GST_BUFFER_DURATION (src);
450 GST_BUFFER_OFFSET_END (dest) = GST_BUFFER_OFFSET_END (src);
453 GST_BUFFER_PTS (dest) = GST_CLOCK_TIME_NONE;
454 GST_BUFFER_DTS (dest) = GST_CLOCK_TIME_NONE;
455 GST_BUFFER_DURATION (dest) = GST_CLOCK_TIME_NONE;
456 GST_BUFFER_OFFSET (dest) = GST_BUFFER_OFFSET_NONE;
457 GST_BUFFER_OFFSET_END (dest) = GST_BUFFER_OFFSET_NONE;
461 if (flags & GST_BUFFER_COPY_MEMORY) {
462 gsize skip, left, len, dest_len, i, bsize;
465 deep = flags & GST_BUFFER_COPY_DEEP;
467 len = GST_BUFFER_MEM_LEN (src);
468 dest_len = GST_BUFFER_MEM_LEN (dest);
472 shared_memory = TRUE;
474 /* copy and make regions of the memory */
475 for (i = 0; i < len && left > 0; i++) {
476 GstMemory *mem = GST_BUFFER_MEM_PTR (src, i);
478 bsize = gst_memory_get_sizes (mem, NULL, NULL);
481 /* don't copy buffer */
484 GstMemory *newmem = NULL;
487 tocopy = MIN (bsize - skip, left);
489 if (tocopy < bsize && !deep && !GST_MEMORY_IS_NO_SHARE (mem)) {
490 /* we need to clip something */
491 newmem = gst_memory_share (mem, skip, tocopy);
493 gst_memory_lock (newmem, GST_LOCK_FLAG_EXCLUSIVE);
498 if (deep || GST_MEMORY_IS_NO_SHARE (mem) || (!newmem && tocopy < bsize)) {
499 /* deep copy or we're not allowed to share this memory
500 * between buffers, always copy then */
501 newmem = gst_memory_copy (mem, skip, tocopy);
502 shared_memory = FALSE;
504 gst_memory_lock (newmem, GST_LOCK_FLAG_EXCLUSIVE);
507 } else if (!newmem) {
508 newmem = _memory_get_exclusive_reference (mem);
509 shared_memory = shared_memory && (newmem == mem);
513 gst_buffer_remove_memory_range (dest, dest_len, -1);
517 _memory_add (dest, -1, newmem);
522 if (flags & GST_BUFFER_COPY_MERGE) {
525 len = GST_BUFFER_MEM_LEN (dest);
526 mem = _get_merged_memory (dest, 0, len);
528 gst_buffer_remove_memory_range (dest, dest_len, -1);
531 _replace_memory (dest, len, 0, len, mem);
532 shared_memory = FALSE;
535 shared_memory = FALSE;
538 if (flags & GST_BUFFER_COPY_META) {
539 /* NOTE: GstGLSyncMeta copying relies on the meta
540 * being copied now, after the buffer data,
541 * so this has to happen last */
542 for (walk = GST_BUFFER_META (src); walk; walk = walk->next) {
543 GstMeta *meta = &walk->meta;
544 const GstMetaInfo *info = meta->info;
546 if (GST_META_FLAG_IS_SET (meta, GST_META_FLAG_POOLED)) {
547 GST_CAT_DEBUG (GST_CAT_BUFFER,
548 "don't copy POOLED meta %p of API type %s", meta,
549 g_type_name (info->api));
550 } else if (!shared_memory
551 && gst_meta_api_type_has_tag (info->api, _gst_meta_tag_memory)) {
552 GST_CAT_DEBUG (GST_CAT_BUFFER,
553 "don't copy memory meta %p of API type %s", meta,
554 g_type_name (info->api));
555 } else if (info->transform_func) {
556 GstMetaTransformCopy copy_data;
558 copy_data.region = region;
559 copy_data.offset = offset;
560 copy_data.size = size;
562 if (!info->transform_func (dest, meta, src,
563 _gst_meta_transform_copy, ©_data)) {
564 GST_CAT_ERROR (GST_CAT_BUFFER,
565 "failed to copy meta %p of API type %s", meta,
566 g_type_name (info->api));
576 gst_buffer_copy_with_flags (const GstBuffer * buffer, GstBufferCopyFlags flags)
580 g_return_val_if_fail (buffer != NULL, NULL);
582 /* create a fresh new buffer */
583 copy = gst_buffer_new ();
585 /* copy what the 'flags' want from our parent */
586 /* FIXME why we can't pass const to gst_buffer_copy_into() ? */
587 if (!gst_buffer_copy_into (copy, (GstBuffer *) buffer, flags, 0, -1))
588 gst_buffer_replace (©, NULL);
591 GST_BUFFER_FLAG_UNSET (copy, GST_BUFFER_FLAG_TAG_MEMORY);
597 _gst_buffer_copy (const GstBuffer * buffer)
599 return gst_buffer_copy_with_flags (buffer, GST_BUFFER_COPY_ALL);
603 * gst_buffer_copy_deep:
604 * @buf: a #GstBuffer.
606 * Create a copy of the given buffer. This will make a newly allocated
607 * copy of the data the source buffer contains.
609 * Returns: (transfer full): a new copy of @buf.
614 gst_buffer_copy_deep (const GstBuffer * buffer)
616 return gst_buffer_copy_with_flags (buffer,
617 GST_BUFFER_COPY_ALL | GST_BUFFER_COPY_DEEP);
620 /* the default dispose function revives the buffer and returns it to the
621 * pool when there is a pool */
623 _gst_buffer_dispose (GstBuffer * buffer)
627 /* no pool, do free */
628 if ((pool = buffer->pool) == NULL)
631 /* keep the buffer alive */
632 gst_buffer_ref (buffer);
633 /* return the buffer to the pool */
634 GST_CAT_LOG (GST_CAT_BUFFER, "release %p to pool %p", buffer, pool);
635 gst_buffer_pool_release_buffer (pool, buffer);
641 _gst_buffer_free (GstBuffer * buffer)
643 GstMetaItem *walk, *next;
647 g_return_if_fail (buffer != NULL);
649 GST_CAT_LOG (GST_CAT_BUFFER, "finalize %p", buffer);
652 for (walk = GST_BUFFER_META (buffer); walk; walk = next) {
653 GstMeta *meta = &walk->meta;
654 const GstMetaInfo *info = meta->info;
656 /* call free_func if any */
658 info->free_func (meta, buffer);
661 /* and free the slice */
662 g_slice_free1 (ITEM_SIZE (info), walk);
665 /* get the size, when unreffing the memory, we could also unref the buffer
667 msize = GST_BUFFER_SLICE_SIZE (buffer);
669 /* free our memory */
670 len = GST_BUFFER_MEM_LEN (buffer);
671 for (i = 0; i < len; i++) {
672 gst_memory_unlock (GST_BUFFER_MEM_PTR (buffer, i), GST_LOCK_FLAG_EXCLUSIVE);
673 gst_memory_unref (GST_BUFFER_MEM_PTR (buffer, i));
676 /* we set msize to 0 when the buffer is part of the memory block */
679 memset (buffer, 0xff, msize);
681 g_slice_free1 (msize, buffer);
683 gst_memory_unref (GST_BUFFER_BUFMEM (buffer));
688 gst_buffer_init (GstBufferImpl * buffer, gsize size)
690 gst_mini_object_init (GST_MINI_OBJECT_CAST (buffer), 0, _gst_buffer_type,
691 (GstMiniObjectCopyFunction) _gst_buffer_copy,
692 (GstMiniObjectDisposeFunction) _gst_buffer_dispose,
693 (GstMiniObjectFreeFunction) _gst_buffer_free);
695 GST_BUFFER_SLICE_SIZE (buffer) = size;
697 GST_BUFFER (buffer)->pool = NULL;
698 GST_BUFFER_PTS (buffer) = GST_CLOCK_TIME_NONE;
699 GST_BUFFER_DTS (buffer) = GST_CLOCK_TIME_NONE;
700 GST_BUFFER_DURATION (buffer) = GST_CLOCK_TIME_NONE;
701 GST_BUFFER_OFFSET (buffer) = GST_BUFFER_OFFSET_NONE;
702 GST_BUFFER_OFFSET_END (buffer) = GST_BUFFER_OFFSET_NONE;
704 GST_BUFFER_MEM_LEN (buffer) = 0;
705 GST_BUFFER_META (buffer) = NULL;
711 * Creates a newly allocated buffer without any data.
715 * Returns: (transfer full): the new #GstBuffer.
718 gst_buffer_new (void)
720 GstBufferImpl *newbuf;
722 newbuf = g_slice_new (GstBufferImpl);
723 GST_CAT_LOG (GST_CAT_BUFFER, "new %p", newbuf);
725 gst_buffer_init (newbuf, sizeof (GstBufferImpl));
727 return GST_BUFFER_CAST (newbuf);
731 * gst_buffer_new_allocate:
732 * @allocator: (transfer none) (allow-none): the #GstAllocator to use, or %NULL to use the
734 * @size: the size in bytes of the new buffer's data.
735 * @params: (transfer none) (allow-none): optional parameters
737 * Tries to create a newly allocated buffer with data of the given size and
738 * extra parameters from @allocator. If the requested amount of memory can't be
739 * allocated, %NULL will be returned. The allocated buffer memory is not cleared.
741 * When @allocator is %NULL, the default memory allocator will be used.
743 * Note that when @size == 0, the buffer will not have memory associated with it.
747 * Returns: (transfer full) (nullable): a new #GstBuffer, or %NULL if
748 * the memory couldn't be allocated.
751 gst_buffer_new_allocate (GstAllocator * allocator, gsize size,
752 GstAllocationParams * params)
763 mem = gst_allocator_alloc (allocator, size, params);
764 if (G_UNLIKELY (mem == NULL))
770 newbuf = gst_buffer_new ();
773 gst_memory_lock (mem, GST_LOCK_FLAG_EXCLUSIVE);
774 _memory_add (newbuf, -1, mem);
777 GST_CAT_LOG (GST_CAT_BUFFER,
778 "new buffer %p of size %" G_GSIZE_FORMAT " from allocator %p", newbuf,
783 asize = sizeof (GstBufferImpl) + size;
784 data = g_slice_alloc (asize);
785 if (G_UNLIKELY (data == NULL))
788 newbuf = GST_BUFFER_CAST (data);
790 gst_buffer_init ((GstBufferImpl *) data, asize);
792 mem = gst_memory_new_wrapped (0, data + sizeof (GstBufferImpl), NULL,
794 _memory_add (newbuf, -1, mem, TRUE);
799 /* allocate memory and buffer, it might be interesting to do this but there
800 * are many complications. We need to keep the memory mapped to access the
801 * buffer fields and the memory for the buffer might be just very slow. We
802 * also need to do some more magic to get the alignment right. */
803 asize = sizeof (GstBufferImpl) + size;
804 mem = gst_allocator_alloc (allocator, asize, align);
805 if (G_UNLIKELY (mem == NULL))
808 /* map the data part and init the buffer in it, set the buffer size to 0 so
809 * that a finalize won't free the buffer */
810 data = gst_memory_map (mem, &asize, NULL, GST_MAP_WRITE);
811 gst_buffer_init ((GstBufferImpl *) data, 0);
812 gst_memory_unmap (mem);
814 /* strip off the buffer */
815 gst_memory_resize (mem, sizeof (GstBufferImpl), size);
817 newbuf = GST_BUFFER_CAST (data);
818 GST_BUFFER_BUFMEM (newbuf) = mem;
821 _memory_add (newbuf, -1, gst_memory_ref (mem), TRUE);
823 GST_BUFFER_FLAG_UNSET (newbuf, GST_BUFFER_FLAG_TAG_MEMORY);
830 GST_CAT_WARNING (GST_CAT_BUFFER,
831 "failed to allocate %" G_GSIZE_FORMAT " bytes", size);
837 * gst_buffer_new_wrapped_full:
838 * @flags: #GstMemoryFlags
839 * @data: (array length=size) (element-type guint8) (transfer none): data to wrap
840 * @maxsize: allocated size of @data
841 * @offset: offset in @data
842 * @size: size of valid data
843 * @user_data: (allow-none): user_data
844 * @notify: (allow-none) (scope async) (closure user_data): called with @user_data when the memory is freed
846 * Allocate a new buffer that wraps the given memory. @data must point to
847 * @maxsize of memory, the wrapped buffer will have the region from @offset and
850 * When the buffer is destroyed, @notify will be called with @user_data.
852 * The prefix/padding must be filled with 0 if @flags contains
853 * #GST_MEMORY_FLAG_ZERO_PREFIXED and #GST_MEMORY_FLAG_ZERO_PADDED respectively.
855 * Returns: (transfer full): a new #GstBuffer
858 gst_buffer_new_wrapped_full (GstMemoryFlags flags, gpointer data,
859 gsize maxsize, gsize offset, gsize size, gpointer user_data,
860 GDestroyNotify notify)
865 newbuf = gst_buffer_new ();
867 gst_memory_new_wrapped (flags, data, maxsize, offset, size, user_data,
869 gst_memory_lock (mem, GST_LOCK_FLAG_EXCLUSIVE);
870 _memory_add (newbuf, -1, mem);
871 GST_BUFFER_FLAG_UNSET (newbuf, GST_BUFFER_FLAG_TAG_MEMORY);
877 * gst_buffer_new_wrapped:
878 * @data: (array length=size) (element-type guint8) (transfer full): data to wrap
879 * @size: allocated size of @data
881 * Creates a new buffer that wraps the given @data. The memory will be freed
882 * with g_free and will be marked writable.
886 * Returns: (transfer full): a new #GstBuffer
889 gst_buffer_new_wrapped (gpointer data, gsize size)
891 return gst_buffer_new_wrapped_full (0, data, size, 0, size, data, g_free);
895 * gst_buffer_n_memory:
896 * @buffer: a #GstBuffer.
898 * Get the amount of memory blocks that this buffer has. This amount is never
899 * larger than what gst_buffer_get_max_memory() returns.
901 * Returns: (transfer full): the amount of memory block in this buffer.
904 gst_buffer_n_memory (GstBuffer * buffer)
906 g_return_val_if_fail (GST_IS_BUFFER (buffer), 0);
908 return GST_BUFFER_MEM_LEN (buffer);
912 * gst_buffer_prepend_memory:
913 * @buffer: a #GstBuffer.
914 * @mem: (transfer full): a #GstMemory.
916 * Prepend the memory block @mem to @buffer. This function takes
917 * ownership of @mem and thus doesn't increase its refcount.
919 * This function is identical to gst_buffer_insert_memory() with an index of 0.
920 * See gst_buffer_insert_memory() for more details.
923 gst_buffer_prepend_memory (GstBuffer * buffer, GstMemory * mem)
925 gst_buffer_insert_memory (buffer, 0, mem);
929 * gst_buffer_append_memory:
930 * @buffer: a #GstBuffer.
931 * @mem: (transfer full): a #GstMemory.
933 * Append the memory block @mem to @buffer. This function takes
934 * ownership of @mem and thus doesn't increase its refcount.
936 * This function is identical to gst_buffer_insert_memory() with an index of -1.
937 * See gst_buffer_insert_memory() for more details.
940 gst_buffer_append_memory (GstBuffer * buffer, GstMemory * mem)
942 gst_buffer_insert_memory (buffer, -1, mem);
946 * gst_buffer_insert_memory:
947 * @buffer: a #GstBuffer.
948 * @idx: the index to add the memory at, or -1 to append it to the end
949 * @mem: (transfer full): a #GstMemory.
951 * Insert the memory block @mem to @buffer at @idx. This function takes ownership
952 * of @mem and thus doesn't increase its refcount.
954 * Only gst_buffer_get_max_memory() can be added to a buffer. If more memory is
955 * added, existing memory blocks will automatically be merged to make room for
959 gst_buffer_insert_memory (GstBuffer * buffer, gint idx, GstMemory * mem)
963 g_return_if_fail (GST_IS_BUFFER (buffer));
964 g_return_if_fail (gst_buffer_is_writable (buffer));
965 g_return_if_fail (mem != NULL);
966 g_return_if_fail (idx == -1 ||
967 (idx >= 0 && idx <= GST_BUFFER_MEM_LEN (buffer)));
969 tmp = _memory_get_exclusive_reference (mem);
970 g_return_if_fail (tmp != NULL);
971 gst_memory_unref (mem);
972 _memory_add (buffer, idx, tmp);
976 _get_mapped (GstBuffer * buffer, guint idx, GstMapInfo * info,
979 GstMemory *mem, *mapped;
981 mem = gst_memory_ref (GST_BUFFER_MEM_PTR (buffer, idx));
983 mapped = gst_memory_make_mapped (mem, info, flags);
986 /* memory changed, lock new memory */
987 gst_memory_lock (mapped, GST_LOCK_FLAG_EXCLUSIVE);
988 GST_BUFFER_MEM_PTR (buffer, idx) = mapped;
989 /* unlock old memory */
990 gst_memory_unlock (mem, GST_LOCK_FLAG_EXCLUSIVE);
991 GST_BUFFER_FLAG_SET (buffer, GST_BUFFER_FLAG_TAG_MEMORY);
993 gst_memory_unref (mem);
999 * gst_buffer_peek_memory:
1000 * @buffer: a #GstBuffer.
1003 * Get the memory block at @idx in @buffer. The memory block stays valid until
1004 * the memory block in @buffer is removed, replaced or merged, typically with
1005 * any call that modifies the memory in @buffer.
1007 * Returns: (transfer none): the #GstMemory at @idx.
1010 gst_buffer_peek_memory (GstBuffer * buffer, guint idx)
1014 g_return_val_if_fail (GST_IS_BUFFER (buffer), NULL);
1015 len = GST_BUFFER_MEM_LEN (buffer);
1016 g_return_val_if_fail (idx < len, NULL);
1018 return GST_BUFFER_MEM_PTR (buffer, idx);
1022 * gst_buffer_get_memory:
1023 * @buffer: a #GstBuffer.
1026 * Get the memory block at index @idx in @buffer.
1028 * Returns: (transfer full): a #GstMemory that contains the data of the
1029 * memory block at @idx. Use gst_memory_unref () after usage.
1032 gst_buffer_get_memory (GstBuffer * buffer, guint idx)
1034 return gst_buffer_get_memory_range (buffer, idx, 1);
1038 * gst_buffer_get_all_memory:
1039 * @buffer: a #GstBuffer.
1041 * Get all the memory block in @buffer. The memory blocks will be merged
1042 * into one large #GstMemory.
1044 * Returns: (transfer full): a #GstMemory that contains the merged memory.
1045 * Use gst_memory_unref () after usage.
1048 gst_buffer_get_all_memory (GstBuffer * buffer)
1050 return gst_buffer_get_memory_range (buffer, 0, -1);
1054 * gst_buffer_get_memory_range:
1055 * @buffer: a #GstBuffer.
1059 * Get @length memory blocks in @buffer starting at @idx. The memory blocks will
1060 * be merged into one large #GstMemory.
1062 * If @length is -1, all memory starting from @idx is merged.
1064 * Returns: (transfer full): a #GstMemory that contains the merged data of @length
1065 * blocks starting at @idx. Use gst_memory_unref () after usage.
1068 gst_buffer_get_memory_range (GstBuffer * buffer, guint idx, gint length)
1072 GST_CAT_DEBUG (GST_CAT_BUFFER, "idx %u, length %d", idx, length);
1074 g_return_val_if_fail (GST_IS_BUFFER (buffer), NULL);
1075 len = GST_BUFFER_MEM_LEN (buffer);
1076 g_return_val_if_fail ((len == 0 && idx == 0 && length == -1) ||
1077 (length == -1 && idx < len) || (length > 0 && length + idx <= len), NULL);
1082 return _get_merged_memory (buffer, idx, length);
1086 * gst_buffer_replace_memory:
1087 * @buffer: a #GstBuffer.
1089 * @mem: (transfer full): a #GstMemory
1091 * Replaces the memory block at index @idx in @buffer with @mem.
1094 gst_buffer_replace_memory (GstBuffer * buffer, guint idx, GstMemory * mem)
1096 gst_buffer_replace_memory_range (buffer, idx, 1, mem);
1100 * gst_buffer_replace_all_memory:
1101 * @buffer: a #GstBuffer.
1102 * @mem: (transfer full): a #GstMemory
1104 * Replaces all memory in @buffer with @mem.
1107 gst_buffer_replace_all_memory (GstBuffer * buffer, GstMemory * mem)
1109 gst_buffer_replace_memory_range (buffer, 0, -1, mem);
1113 * gst_buffer_replace_memory_range:
1114 * @buffer: a #GstBuffer.
1116 * @length: a length should not be 0
1117 * @mem: (transfer full): a #GstMemory
1119 * Replaces @length memory blocks in @buffer starting at @idx with @mem.
1121 * If @length is -1, all memory starting from @idx will be removed and
1122 * replaced with @mem.
1124 * @buffer should be writable.
1127 gst_buffer_replace_memory_range (GstBuffer * buffer, guint idx, gint length,
1132 g_return_if_fail (GST_IS_BUFFER (buffer));
1133 g_return_if_fail (gst_buffer_is_writable (buffer));
1135 GST_CAT_DEBUG (GST_CAT_BUFFER, "idx %u, length %d, %p", idx, length, mem);
1137 len = GST_BUFFER_MEM_LEN (buffer);
1138 g_return_if_fail ((len == 0 && idx == 0 && length == -1) ||
1139 (length == -1 && idx < len) || (length > 0 && length + idx <= len));
1144 _replace_memory (buffer, len, idx, length, mem);
1148 * gst_buffer_remove_memory:
1149 * @buffer: a #GstBuffer.
1152 * Remove the memory block in @b at index @i.
1155 gst_buffer_remove_memory (GstBuffer * buffer, guint idx)
1157 gst_buffer_remove_memory_range (buffer, idx, 1);
1161 * gst_buffer_remove_all_memory:
1162 * @buffer: a #GstBuffer.
1164 * Remove all the memory blocks in @buffer.
1167 gst_buffer_remove_all_memory (GstBuffer * buffer)
1169 gst_buffer_remove_memory_range (buffer, 0, -1);
1173 * gst_buffer_remove_memory_range:
1174 * @buffer: a #GstBuffer.
1178 * Remove @length memory blocks in @buffer starting from @idx.
1180 * @length can be -1, in which case all memory starting from @idx is removed.
1183 gst_buffer_remove_memory_range (GstBuffer * buffer, guint idx, gint length)
1187 g_return_if_fail (GST_IS_BUFFER (buffer));
1188 g_return_if_fail (gst_buffer_is_writable (buffer));
1190 GST_CAT_DEBUG (GST_CAT_BUFFER, "idx %u, length %d", idx, length);
1192 len = GST_BUFFER_MEM_LEN (buffer);
1193 g_return_if_fail ((len == 0 && idx == 0 && length == -1) ||
1194 (length == -1 && idx < len) || length + idx <= len);
1199 _replace_memory (buffer, len, idx, length, NULL);
1203 * gst_buffer_find_memory:
1204 * @buffer: a #GstBuffer.
1205 * @offset: an offset
1207 * @idx: (out): pointer to index
1208 * @length: (out): pointer to length
1209 * @skip: (out): pointer to skip
1211 * Find the memory blocks that span @size bytes starting from @offset
1214 * When this function returns %TRUE, @idx will contain the index of the first
1215 * memory block where the byte for @offset can be found and @length contains the
1216 * number of memory blocks containing the @size remaining bytes. @skip contains
1217 * the number of bytes to skip in the memory block at @idx to get to the byte
1220 * @size can be -1 to get all the memory blocks after @idx.
1222 * Returns: %TRUE when @size bytes starting from @offset could be found in
1223 * @buffer and @idx, @length and @skip will be filled.
1226 gst_buffer_find_memory (GstBuffer * buffer, gsize offset, gsize size,
1227 guint * idx, guint * length, gsize * skip)
1229 guint i, len, found;
1231 g_return_val_if_fail (GST_IS_BUFFER (buffer), FALSE);
1232 g_return_val_if_fail (idx != NULL, FALSE);
1233 g_return_val_if_fail (length != NULL, FALSE);
1234 g_return_val_if_fail (skip != NULL, FALSE);
1236 len = GST_BUFFER_MEM_LEN (buffer);
1239 for (i = 0; i < len; i++) {
1243 mem = GST_BUFFER_MEM_PTR (buffer, i);
1244 s = gst_memory_get_sizes (mem, NULL, NULL);
1247 /* block before offset, or empty block, skip */
1250 /* block after offset */
1252 /* first block, remember index and offset */
1256 /* return remaining blocks */
1263 /* count the amount of found bytes */
1265 if (found >= size) {
1266 /* we have enough bytes */
1267 *length = i - *idx + 1;
1276 * gst_buffer_is_memory_range_writable:
1277 * @buffer: a #GstBuffer.
1279 * @length: a length should not be 0
1281 * Check if @length memory blocks in @buffer starting from @idx are writable.
1283 * @length can be -1 to check all the memory blocks after @idx.
1285 * Note that this function does not check if @buffer is writable, use
1286 * gst_buffer_is_writable() to check that if needed.
1288 * Returns: %TRUE if the memory range is writable
1293 gst_buffer_is_memory_range_writable (GstBuffer * buffer, guint idx, gint length)
1297 g_return_val_if_fail (GST_IS_BUFFER (buffer), FALSE);
1299 GST_CAT_DEBUG (GST_CAT_BUFFER, "idx %u, length %d", idx, length);
1301 len = GST_BUFFER_MEM_LEN (buffer);
1302 g_return_val_if_fail ((len == 0 && idx == 0 && length == -1) ||
1303 (length == -1 && idx < len) || (length > 0 && length + idx <= len),
1311 for (i = 0; i < len; i++) {
1312 if (!gst_memory_is_writable (GST_BUFFER_MEM_PTR (buffer, i + idx)))
1319 * gst_buffer_is_all_memory_writable:
1320 * @buffer: a #GstBuffer.
1322 * Check if all memory blocks in @buffer are writable.
1324 * Note that this function does not check if @buffer is writable, use
1325 * gst_buffer_is_writable() to check that if needed.
1327 * Returns: %TRUE if all memory blocks in @buffer are writable
1332 gst_buffer_is_all_memory_writable (GstBuffer * buffer)
1334 return gst_buffer_is_memory_range_writable (buffer, 0, -1);
1338 * gst_buffer_get_sizes:
1339 * @buffer: a #GstBuffer.
1340 * @offset: (out) (allow-none): a pointer to the offset
1341 * @maxsize: (out) (allow-none): a pointer to the maxsize
1343 * Get the total size of the memory blocks in @b.
1345 * When not %NULL, @offset will contain the offset of the data in the
1346 * first memory block in @buffer and @maxsize will contain the sum of
1347 * the size and @offset and the amount of extra padding on the last
1348 * memory block. @offset and @maxsize can be used to resize the
1349 * buffer memory blocks with gst_buffer_resize().
1351 * Returns: total size of the memory blocks in @buffer.
1354 gst_buffer_get_sizes (GstBuffer * buffer, gsize * offset, gsize * maxsize)
1356 return gst_buffer_get_sizes_range (buffer, 0, -1, offset, maxsize);
1360 * gst_buffer_get_size:
1361 * @buffer: a #GstBuffer.
1363 * Get the total size of the memory blocks in @buffer.
1365 * Returns: total size of the memory blocks in @buffer.
1368 gst_buffer_get_size (GstBuffer * buffer)
1370 return gst_buffer_get_sizes_range (buffer, 0, -1, NULL, NULL);
1374 * gst_buffer_get_sizes_range:
1375 * @buffer: a #GstBuffer.
1378 * @offset: (out) (allow-none): a pointer to the offset
1379 * @maxsize: (out) (allow-none): a pointer to the maxsize
1381 * Get the total size of @length memory blocks stating from @idx in @buffer.
1383 * When not %NULL, @offset will contain the offset of the data in the
1384 * memory block in @buffer at @idx and @maxsize will contain the sum of the size
1385 * and @offset and the amount of extra padding on the memory block at @idx +
1387 * @offset and @maxsize can be used to resize the buffer memory blocks with
1388 * gst_buffer_resize_range().
1390 * Returns: total size of @length memory blocks starting at @idx in @buffer.
1393 gst_buffer_get_sizes_range (GstBuffer * buffer, guint idx, gint length,
1394 gsize * offset, gsize * maxsize)
1400 g_return_val_if_fail (GST_IS_BUFFER (buffer), 0);
1401 len = GST_BUFFER_MEM_LEN (buffer);
1402 g_return_val_if_fail ((len == 0 && idx == 0 && length == -1) ||
1403 (length == -1 && idx < len) || (length + idx <= len), 0);
1408 if (G_LIKELY (length == 1)) {
1410 mem = GST_BUFFER_MEM_PTR (buffer, idx);
1411 size = gst_memory_get_sizes (mem, offset, maxsize);
1417 size = offs = extra = 0;
1418 for (i = idx; i < end; i++) {
1421 mem = GST_BUFFER_MEM_PTR (buffer, i);
1422 s = gst_memory_get_sizes (mem, &o, &ms);
1426 /* first size, take accumulated data before as the offset */
1430 /* save the amount of data after this block */
1431 extra = ms - (o + s);
1433 /* empty block, add as extra */
1440 *maxsize = offs + size + extra;
1446 * gst_buffer_resize:
1447 * @buffer: a #GstBuffer.
1448 * @offset: the offset adjustment
1449 * @size: the new size or -1 to just adjust the offset
1451 * Set the offset and total size of the memory blocks in @buffer.
1454 gst_buffer_resize (GstBuffer * buffer, gssize offset, gssize size)
1456 gst_buffer_resize_range (buffer, 0, -1, offset, size);
1460 * gst_buffer_set_size:
1461 * @buffer: a #GstBuffer.
1462 * @size: the new size
1464 * Set the total size of the memory blocks in @buffer.
1467 gst_buffer_set_size (GstBuffer * buffer, gssize size)
1469 gst_buffer_resize_range (buffer, 0, -1, 0, size);
1473 * gst_buffer_resize_range:
1474 * @buffer: a #GstBuffer.
1477 * @offset: the offset adjustment
1478 * @size: the new size or -1 to just adjust the offset
1480 * Set the total size of the @length memory blocks starting at @idx in
1483 * Returns: %TRUE if resizing succeeded, %FALSE otherwise.
1486 gst_buffer_resize_range (GstBuffer * buffer, guint idx, gint length,
1487 gssize offset, gssize size)
1490 gsize bsize, bufsize, bufoffs, bufmax;
1492 g_return_val_if_fail (gst_buffer_is_writable (buffer), FALSE);
1493 g_return_val_if_fail (size >= -1, FALSE);
1495 len = GST_BUFFER_MEM_LEN (buffer);
1496 g_return_val_if_fail ((len == 0 && idx == 0 && length == -1) ||
1497 (length == -1 && idx < len) || (length + idx <= len), FALSE);
1502 bufsize = gst_buffer_get_sizes_range (buffer, idx, length, &bufoffs, &bufmax);
1504 GST_CAT_LOG (GST_CAT_BUFFER, "trim %p %" G_GSSIZE_FORMAT "-%" G_GSSIZE_FORMAT
1505 " size:%" G_GSIZE_FORMAT " offs:%" G_GSIZE_FORMAT " max:%"
1506 G_GSIZE_FORMAT, buffer, offset, size, bufsize, bufoffs, bufmax);
1508 /* we can't go back further than the current offset or past the end of the
1510 g_return_val_if_fail ((offset < 0 && bufoffs >= -offset) || (offset >= 0
1511 && bufoffs + offset <= bufmax), FALSE);
1513 g_return_val_if_fail (bufsize >= offset, FALSE);
1514 size = bufsize - offset;
1516 g_return_val_if_fail (bufmax >= bufoffs + offset + size, FALSE);
1519 if (offset == 0 && size == bufsize)
1524 for (i = idx; i < end; i++) {
1528 mem = GST_BUFFER_MEM_PTR (buffer, i);
1529 bsize = gst_memory_get_sizes (mem, NULL, NULL);
1532 /* last buffer always gets resized to the remaining size */
1535 /* shrink buffers before the offset */
1536 else if ((gssize) bsize <= offset) {
1538 noffs = offset - bsize;
1541 /* clip other buffers */
1543 left = MIN (bsize - offset, size);
1545 if (offset != 0 || left != bsize) {
1546 if (gst_memory_is_writable (mem)) {
1547 gst_memory_resize (mem, offset, left);
1549 GstMemory *newmem = NULL;
1551 if (!GST_MEMORY_IS_NO_SHARE (mem))
1552 newmem = gst_memory_share (mem, offset, left);
1555 newmem = gst_memory_copy (mem, offset, left);
1560 gst_memory_lock (newmem, GST_LOCK_FLAG_EXCLUSIVE);
1561 GST_BUFFER_MEM_PTR (buffer, i) = newmem;
1562 gst_memory_unlock (mem, GST_LOCK_FLAG_EXCLUSIVE);
1563 gst_memory_unref (mem);
1565 GST_BUFFER_FLAG_SET (buffer, GST_BUFFER_FLAG_TAG_MEMORY);
1578 * @buffer: a #GstBuffer.
1579 * @info: (out): info about the mapping
1580 * @flags: flags for the mapping
1582 * This function fills @info with the #GstMapInfo of all merged memory
1583 * blocks in @buffer.
1585 * @flags describe the desired access of the memory. When @flags is
1586 * #GST_MAP_WRITE, @buffer should be writable (as returned from
1587 * gst_buffer_is_writable()).
1589 * When @buffer is writable but the memory isn't, a writable copy will
1590 * automatically be created and returned. The readonly copy of the
1591 * buffer memory will then also be replaced with this writable copy.
1593 * The memory in @info should be unmapped with gst_buffer_unmap() after
1596 * Returns: %TRUE if the map succeeded and @info contains valid data.
1599 gst_buffer_map (GstBuffer * buffer, GstMapInfo * info, GstMapFlags flags)
1601 return gst_buffer_map_range (buffer, 0, -1, info, flags);
1605 * gst_buffer_map_range:
1606 * @buffer: a #GstBuffer.
1609 * @info: (out): info about the mapping
1610 * @flags: flags for the mapping
1612 * This function fills @info with the #GstMapInfo of @length merged memory blocks
1613 * starting at @idx in @buffer. When @length is -1, all memory blocks starting
1614 * from @idx are merged and mapped.
1616 * @flags describe the desired access of the memory. When @flags is
1617 * #GST_MAP_WRITE, @buffer should be writable (as returned from
1618 * gst_buffer_is_writable()).
1620 * When @buffer is writable but the memory isn't, a writable copy will
1621 * automatically be created and returned. The readonly copy of the buffer memory
1622 * will then also be replaced with this writable copy.
1624 * The memory in @info should be unmapped with gst_buffer_unmap() after usage.
1626 * Returns: %TRUE if the map succeeded and @info contains valid
1630 gst_buffer_map_range (GstBuffer * buffer, guint idx, gint length,
1631 GstMapInfo * info, GstMapFlags flags)
1633 GstMemory *mem, *nmem;
1634 gboolean write, writable;
1637 g_return_val_if_fail (GST_IS_BUFFER (buffer), FALSE);
1638 g_return_val_if_fail (info != NULL, FALSE);
1639 len = GST_BUFFER_MEM_LEN (buffer);
1640 g_return_val_if_fail ((len == 0 && idx == 0 && length == -1) ||
1641 (length == -1 && idx < len) || (length > 0
1642 && length + idx <= len), FALSE);
1644 GST_CAT_LOG (GST_CAT_BUFFER, "buffer %p, idx %u, length %d, flags %04x",
1645 buffer, idx, length, flags);
1647 write = (flags & GST_MAP_WRITE) != 0;
1648 writable = gst_buffer_is_writable (buffer);
1650 /* check if we can write when asked for write access */
1651 if (G_UNLIKELY (write && !writable))
1657 mem = _get_merged_memory (buffer, idx, length);
1658 if (G_UNLIKELY (mem == NULL))
1661 /* now try to map */
1662 nmem = gst_memory_make_mapped (mem, info, flags);
1663 if (G_UNLIKELY (nmem == NULL))
1666 /* if we merged or when the map returned a different memory, we try to replace
1667 * the memory in the buffer */
1668 if (G_UNLIKELY (length > 1 || nmem != mem)) {
1669 /* if the buffer is writable, replace the memory */
1671 _replace_memory (buffer, len, idx, length, gst_memory_ref (nmem));
1674 GST_CAT_DEBUG (GST_CAT_PERFORMANCE,
1675 "temporary mapping for memory %p in buffer %p", nmem, buffer);
1684 GST_WARNING_OBJECT (buffer, "write map requested on non-writable buffer");
1685 g_critical ("write map requested on non-writable buffer");
1686 memset (info, 0, sizeof (GstMapInfo));
1691 /* empty buffer, we need to return NULL */
1692 GST_DEBUG_OBJECT (buffer, "can't get buffer memory");
1693 memset (info, 0, sizeof (GstMapInfo));
1698 GST_DEBUG_OBJECT (buffer, "cannot map memory");
1699 memset (info, 0, sizeof (GstMapInfo));
1706 * @buffer: a #GstBuffer.
1707 * @info: a #GstMapInfo
1709 * Release the memory previously mapped with gst_buffer_map().
1712 gst_buffer_unmap (GstBuffer * buffer, GstMapInfo * info)
1714 g_return_if_fail (GST_IS_BUFFER (buffer));
1715 g_return_if_fail (info != NULL);
1717 /* we need to check for NULL, it is possible that we tried to map a buffer
1718 * without memory and we should be able to unmap that fine */
1719 if (G_LIKELY (info->memory)) {
1720 gst_memory_unmap (info->memory, info);
1721 gst_memory_unref (info->memory);
1727 * @buffer: a #GstBuffer.
1728 * @offset: the offset to fill
1729 * @src: (array length=size) (element-type guint8): the source address
1730 * @size: the size to fill
1732 * Copy @size bytes from @src to @buffer at @offset.
1734 * Returns: The amount of bytes copied. This value can be lower than @size
1735 * when @buffer did not contain enough data.
1738 gst_buffer_fill (GstBuffer * buffer, gsize offset, gconstpointer src,
1742 const guint8 *ptr = src;
1744 g_return_val_if_fail (GST_IS_BUFFER (buffer), 0);
1745 g_return_val_if_fail (gst_buffer_is_writable (buffer), 0);
1746 g_return_val_if_fail (src != NULL || size == 0, 0);
1748 GST_CAT_LOG (GST_CAT_BUFFER,
1749 "buffer %p, offset %" G_GSIZE_FORMAT ", size %" G_GSIZE_FORMAT, buffer,
1752 len = GST_BUFFER_MEM_LEN (buffer);
1755 for (i = 0; i < len && left > 0; i++) {
1760 mem = _get_mapped (buffer, i, &info, GST_MAP_WRITE);
1761 if (info.size > offset) {
1762 /* we have enough */
1763 tocopy = MIN (info.size - offset, left);
1764 memcpy ((guint8 *) info.data + offset, ptr, tocopy);
1769 /* offset past buffer, skip */
1770 offset -= info.size;
1772 gst_memory_unmap (mem, &info);
1778 * gst_buffer_extract:
1779 * @buffer: a #GstBuffer.
1780 * @offset: the offset to extract
1781 * @dest: the destination address
1782 * @size: the size to extract
1784 * Copy @size bytes starting from @offset in @buffer to @dest.
1786 * Returns: The amount of bytes extracted. This value can be lower than @size
1787 * when @buffer did not contain enough data.
1790 gst_buffer_extract (GstBuffer * buffer, gsize offset, gpointer dest, gsize size)
1795 g_return_val_if_fail (GST_IS_BUFFER (buffer), 0);
1796 g_return_val_if_fail (dest != NULL, 0);
1798 GST_CAT_LOG (GST_CAT_BUFFER,
1799 "buffer %p, offset %" G_GSIZE_FORMAT ", size %" G_GSIZE_FORMAT, buffer,
1802 len = GST_BUFFER_MEM_LEN (buffer);
1805 for (i = 0; i < len && left > 0; i++) {
1810 mem = _get_mapped (buffer, i, &info, GST_MAP_READ);
1811 if (info.size > offset) {
1812 /* we have enough */
1813 tocopy = MIN (info.size - offset, left);
1814 memcpy (ptr, (guint8 *) info.data + offset, tocopy);
1819 /* offset past buffer, skip */
1820 offset -= info.size;
1822 gst_memory_unmap (mem, &info);
1828 * gst_buffer_memcmp:
1829 * @buffer: a #GstBuffer.
1830 * @offset: the offset in @buffer
1831 * @mem: (array length=size) (element-type guint8): the memory to compare
1832 * @size: the size to compare
1834 * Compare @size bytes starting from @offset in @buffer with the memory in @mem.
1836 * Returns: 0 if the memory is equal.
1839 gst_buffer_memcmp (GstBuffer * buffer, gsize offset, gconstpointer mem,
1843 const guint8 *ptr = mem;
1846 g_return_val_if_fail (GST_IS_BUFFER (buffer), 0);
1847 g_return_val_if_fail (mem != NULL, 0);
1849 GST_CAT_LOG (GST_CAT_BUFFER,
1850 "buffer %p, offset %" G_GSIZE_FORMAT ", size %" G_GSIZE_FORMAT, buffer,
1853 if (G_UNLIKELY (gst_buffer_get_size (buffer) < offset + size))
1856 len = GST_BUFFER_MEM_LEN (buffer);
1858 for (i = 0; i < len && size > 0 && res == 0; i++) {
1863 mem = _get_mapped (buffer, i, &info, GST_MAP_READ);
1864 if (info.size > offset) {
1865 /* we have enough */
1866 tocmp = MIN (info.size - offset, size);
1867 res = memcmp (ptr, (guint8 *) info.data + offset, tocmp);
1872 /* offset past buffer, skip */
1873 offset -= info.size;
1875 gst_memory_unmap (mem, &info);
1881 * gst_buffer_memset:
1882 * @buffer: a #GstBuffer.
1883 * @offset: the offset in @buffer
1884 * @val: the value to set
1885 * @size: the size to set
1887 * Fill @buf with @size bytes with @val starting from @offset.
1889 * Returns: The amount of bytes filled. This value can be lower than @size
1890 * when @buffer did not contain enough data.
1893 gst_buffer_memset (GstBuffer * buffer, gsize offset, guint8 val, gsize size)
1897 g_return_val_if_fail (GST_IS_BUFFER (buffer), 0);
1898 g_return_val_if_fail (gst_buffer_is_writable (buffer), 0);
1900 GST_CAT_LOG (GST_CAT_BUFFER,
1901 "buffer %p, offset %" G_GSIZE_FORMAT ", val %02x, size %" G_GSIZE_FORMAT,
1902 buffer, offset, val, size);
1904 len = GST_BUFFER_MEM_LEN (buffer);
1907 for (i = 0; i < len && left > 0; i++) {
1912 mem = _get_mapped (buffer, i, &info, GST_MAP_WRITE);
1913 if (info.size > offset) {
1914 /* we have enough */
1915 toset = MIN (info.size - offset, left);
1916 memset ((guint8 *) info.data + offset, val, toset);
1920 /* offset past buffer, skip */
1921 offset -= info.size;
1923 gst_memory_unmap (mem, &info);
1929 * gst_buffer_copy_region:
1930 * @parent: a #GstBuffer.
1931 * @flags: the #GstBufferCopyFlags
1932 * @offset: the offset into parent #GstBuffer at which the new sub-buffer
1934 * @size: the size of the new #GstBuffer sub-buffer, in bytes. If -1, all
1937 * Creates a sub-buffer from @parent at @offset and @size.
1938 * This sub-buffer uses the actual memory space of the parent buffer.
1939 * This function will copy the offset and timestamp fields when the
1940 * offset is 0. If not, they will be set to #GST_CLOCK_TIME_NONE and
1941 * #GST_BUFFER_OFFSET_NONE.
1942 * If @offset equals 0 and @size equals the total size of @buffer, the
1943 * duration and offset end fields are also copied. If not they will be set
1944 * to #GST_CLOCK_TIME_NONE and #GST_BUFFER_OFFSET_NONE.
1948 * Returns: (transfer full): the new #GstBuffer or %NULL if the arguments were
1952 gst_buffer_copy_region (GstBuffer * buffer, GstBufferCopyFlags flags,
1953 gsize offset, gsize size)
1957 g_return_val_if_fail (buffer != NULL, NULL);
1959 /* create the new buffer */
1960 copy = gst_buffer_new ();
1962 GST_CAT_LOG (GST_CAT_BUFFER, "new region copy %p of %p %" G_GSIZE_FORMAT
1963 "-%" G_GSIZE_FORMAT, copy, buffer, offset, size);
1965 if (!gst_buffer_copy_into (copy, buffer, flags, offset, size))
1966 gst_buffer_replace (©, NULL);
1972 * gst_buffer_append:
1973 * @buf1: (transfer full): the first source #GstBuffer to append.
1974 * @buf2: (transfer full): the second source #GstBuffer to append.
1976 * Append all the memory from @buf2 to @buf1. The result buffer will contain a
1977 * concatenation of the memory of @buf1 and @buf2.
1979 * Returns: (transfer full): the new #GstBuffer that contains the memory
1980 * of the two source buffers.
1983 gst_buffer_append (GstBuffer * buf1, GstBuffer * buf2)
1985 return gst_buffer_append_region (buf1, buf2, 0, -1);
1989 * gst_buffer_append_region:
1990 * @buf1: (transfer full): the first source #GstBuffer to append.
1991 * @buf2: (transfer full): the second source #GstBuffer to append.
1992 * @offset: the offset in @buf2
1993 * @size: the size or -1 of @buf2
1995 * Append @size bytes at @offset from @buf2 to @buf1. The result buffer will
1996 * contain a concatenation of the memory of @buf1 and the requested region of
1999 * Returns: (transfer full): the new #GstBuffer that contains the memory
2000 * of the two source buffers.
2003 gst_buffer_append_region (GstBuffer * buf1, GstBuffer * buf2, gssize offset,
2008 g_return_val_if_fail (GST_IS_BUFFER (buf1), NULL);
2009 g_return_val_if_fail (GST_IS_BUFFER (buf2), NULL);
2011 buf1 = gst_buffer_make_writable (buf1);
2012 buf2 = gst_buffer_make_writable (buf2);
2014 gst_buffer_resize (buf2, offset, size);
2016 len = GST_BUFFER_MEM_LEN (buf2);
2017 for (i = 0; i < len; i++) {
2020 mem = GST_BUFFER_MEM_PTR (buf2, i);
2021 GST_BUFFER_MEM_PTR (buf2, i) = NULL;
2022 _memory_add (buf1, -1, mem);
2025 GST_BUFFER_MEM_LEN (buf2) = 0;
2026 GST_BUFFER_FLAG_SET (buf2, GST_BUFFER_FLAG_TAG_MEMORY);
2027 gst_buffer_unref (buf2);
2033 * gst_buffer_get_meta:
2034 * @buffer: a #GstBuffer
2035 * @api: the #GType of an API
2037 * Get the metadata for @api on buffer. When there is no such metadata, %NULL is
2038 * returned. If multiple metadata with the given @api are attached to this
2039 * buffer only the first one is returned. To handle multiple metadata with a
2040 * given API use gst_buffer_iterate_meta() or gst_buffer_foreach_meta() instead
2041 * and check the meta->info.api member for the API type.
2043 * Returns: (transfer none) (nullable): the metadata for @api on
2047 gst_buffer_get_meta (GstBuffer * buffer, GType api)
2050 GstMeta *result = NULL;
2052 g_return_val_if_fail (buffer != NULL, NULL);
2053 g_return_val_if_fail (api != 0, NULL);
2055 /* find GstMeta of the requested API */
2056 for (item = GST_BUFFER_META (buffer); item; item = item->next) {
2057 GstMeta *meta = &item->meta;
2058 if (meta->info->api == api) {
2067 * gst_buffer_add_meta:
2068 * @buffer: a #GstBuffer
2069 * @info: a #GstMetaInfo
2070 * @params: params for @info
2072 * Add metadata for @info to @buffer using the parameters in @params.
2074 * Returns: (transfer none): the metadata for the api in @info on @buffer.
2077 gst_buffer_add_meta (GstBuffer * buffer, const GstMetaInfo * info,
2081 GstMeta *result = NULL;
2084 g_return_val_if_fail (buffer != NULL, NULL);
2085 g_return_val_if_fail (info != NULL, NULL);
2086 g_return_val_if_fail (gst_buffer_is_writable (buffer), NULL);
2088 /* create a new slice */
2089 size = ITEM_SIZE (info);
2090 item = g_slice_alloc (size);
2091 result = &item->meta;
2092 result->info = info;
2093 result->flags = GST_META_FLAG_NONE;
2095 GST_CAT_DEBUG (GST_CAT_BUFFER,
2096 "alloc metadata %p (%s) of size %" G_GSIZE_FORMAT, result,
2097 g_type_name (info->type), info->size);
2099 /* call the init_func when needed */
2100 if (info->init_func)
2101 if (!info->init_func (result, params, buffer))
2104 /* and add to the list of metadata */
2105 item->next = GST_BUFFER_META (buffer);
2106 GST_BUFFER_META (buffer) = item;
2112 g_slice_free1 (size, item);
2118 * gst_buffer_remove_meta:
2119 * @buffer: a #GstBuffer
2122 * Remove the metadata for @meta on @buffer.
2124 * Returns: %TRUE if the metadata existed and was removed, %FALSE if no such
2125 * metadata was on @buffer.
2128 gst_buffer_remove_meta (GstBuffer * buffer, GstMeta * meta)
2130 GstMetaItem *walk, *prev;
2132 g_return_val_if_fail (buffer != NULL, FALSE);
2133 g_return_val_if_fail (meta != NULL, FALSE);
2134 g_return_val_if_fail (gst_buffer_is_writable (buffer), FALSE);
2135 g_return_val_if_fail (!GST_META_FLAG_IS_SET (meta, GST_META_FLAG_LOCKED),
2138 /* find the metadata and delete */
2139 prev = GST_BUFFER_META (buffer);
2140 for (walk = prev; walk; walk = walk->next) {
2141 GstMeta *m = &walk->meta;
2143 const GstMetaInfo *info = meta->info;
2145 /* remove from list */
2146 if (GST_BUFFER_META (buffer) == walk)
2147 GST_BUFFER_META (buffer) = walk->next;
2149 prev->next = walk->next;
2150 /* call free_func if any */
2151 if (info->free_func)
2152 info->free_func (m, buffer);
2154 /* and free the slice */
2155 g_slice_free1 (ITEM_SIZE (info), walk);
2160 return walk != NULL;
2164 * gst_buffer_iterate_meta:
2165 * @buffer: a #GstBuffer
2166 * @state: an opaque state pointer
2168 * Retrieve the next #GstMeta after @current. If @state points
2169 * to %NULL, the first metadata is returned.
2171 * @state will be updated with an opaque state pointer
2173 * Returns: (transfer none) (nullable): The next #GstMeta or %NULL
2174 * when there are no more items.
2177 gst_buffer_iterate_meta (GstBuffer * buffer, gpointer * state)
2181 g_return_val_if_fail (buffer != NULL, NULL);
2182 g_return_val_if_fail (state != NULL, NULL);
2184 meta = (GstMetaItem **) state;
2186 /* state NULL, move to first item */
2187 *meta = GST_BUFFER_META (buffer);
2189 /* state !NULL, move to next item in list */
2190 *meta = (*meta)->next;
2193 return &(*meta)->meta;
2199 * gst_buffer_foreach_meta:
2200 * @buffer: a #GstBuffer
2201 * @func: (scope call): a #GstBufferForeachMetaFunc to call
2202 * @user_data: (closure): user data passed to @func
2204 * Call @func with @user_data for each meta in @buffer.
2206 * @func can modify the passed meta pointer or its contents. The return value
2207 * of @func define if this function returns or if the remaining metadata items
2208 * in the buffer should be skipped.
2210 * Returns: %FALSE when @func returned %FALSE for one of the metadata.
2213 gst_buffer_foreach_meta (GstBuffer * buffer, GstBufferForeachMetaFunc func,
2216 GstMetaItem *walk, *prev, *next;
2217 gboolean res = TRUE;
2219 g_return_val_if_fail (buffer != NULL, FALSE);
2220 g_return_val_if_fail (func != NULL, FALSE);
2222 /* find the metadata and delete */
2223 prev = GST_BUFFER_META (buffer);
2224 for (walk = prev; walk; walk = next) {
2227 m = new = &walk->meta;
2230 res = func (buffer, &new, user_data);
2233 const GstMetaInfo *info = m->info;
2235 GST_CAT_DEBUG (GST_CAT_BUFFER, "remove metadata %p (%s)", m,
2236 g_type_name (info->type));
2238 g_return_val_if_fail (gst_buffer_is_writable (buffer), FALSE);
2239 g_return_val_if_fail (!GST_META_FLAG_IS_SET (m, GST_META_FLAG_LOCKED),
2242 /* remove from list */
2243 if (GST_BUFFER_META (buffer) == walk)
2244 GST_BUFFER_META (buffer) = next;
2248 /* call free_func if any */
2249 if (info->free_func)
2250 info->free_func (m, buffer);
2252 /* and free the slice */
2253 g_slice_free1 (ITEM_SIZE (info), walk);
2262 * gst_buffer_extract_dup:
2263 * @buffer: a #GstBuffer
2264 * @offset: the offset to extract
2265 * @size: the size to extract
2266 * @dest: (array length=dest_size) (element-type guint8) (out): A pointer where
2267 * the destination array will be written.
2268 * @dest_size: (out): A location where the size of @dest can be written
2270 * Extracts a copy of at most @size bytes the data at @offset into a #GBytes.
2271 * @dest must be freed using g_free() when done.
2277 gst_buffer_extract_dup (GstBuffer * buffer, gsize offset, gsize size,
2278 gpointer * dest, gsize * dest_size)
2282 real_size = gst_buffer_get_size (buffer);
2284 *dest = g_malloc (MIN (real_size - offset, size));
2286 *dest_size = gst_buffer_extract (buffer, offset, *dest, size);
2289 GST_DEBUG_CATEGORY (gst_parent_buffer_meta_debug);
2292 * gst_buffer_add_parent_buffer_meta:
2293 * @buffer: (transfer none): a #GstBuffer
2294 * @ref: (transfer none): a #GstBuffer to ref
2296 * Add a #GstParentBufferMeta to @buffer that holds a reference on
2297 * @ref until the buffer is freed.
2299 * Returns: (transfer none): The #GstParentBufferMeta that was added to the buffer
2303 GstParentBufferMeta *
2304 gst_buffer_add_parent_buffer_meta (GstBuffer * buffer, GstBuffer * ref)
2306 GstParentBufferMeta *meta;
2308 g_return_val_if_fail (GST_IS_BUFFER (ref), NULL);
2311 (GstParentBufferMeta *) gst_buffer_add_meta (buffer,
2312 GST_PARENT_BUFFER_META_INFO, NULL);
2317 meta->buffer = gst_buffer_ref (ref);
2323 _gst_parent_buffer_meta_transform (GstBuffer * dest, GstMeta * meta,
2324 GstBuffer * buffer, GQuark type, gpointer data)
2326 GstParentBufferMeta *dmeta, *smeta;
2328 smeta = (GstParentBufferMeta *) meta;
2330 if (GST_META_TRANSFORM_IS_COPY (type)) {
2331 /* copy over the reference to the parent buffer.
2332 * Usually, this meta means we need to keep the parent buffer
2333 * alive because one of the child memories is in use, which
2334 * might not be the case if memory is deep copied or sub-regioned,
2335 * but we can't tell, so keep the meta */
2336 dmeta = gst_buffer_add_parent_buffer_meta (dest, smeta->buffer);
2340 GST_CAT_DEBUG (gst_parent_buffer_meta_debug,
2341 "copy buffer reference metadata");
2347 _gst_parent_buffer_meta_free (GstParentBufferMeta * parent_meta,
2350 GST_CAT_DEBUG (gst_parent_buffer_meta_debug,
2351 "Dropping reference on buffer %p", parent_meta->buffer);
2352 gst_buffer_unref (parent_meta->buffer);
2356 _gst_parent_buffer_meta_init (GstParentBufferMeta * parent_meta,
2357 gpointer params, GstBuffer * buffer)
2359 static volatile gsize _init;
2361 if (g_once_init_enter (&_init)) {
2362 GST_DEBUG_CATEGORY_INIT (gst_parent_buffer_meta_debug, "glbufferrefmeta", 0,
2364 g_once_init_leave (&_init, 1);
2367 parent_meta->buffer = NULL;
2373 gst_parent_buffer_meta_api_get_type (void)
2375 static volatile GType type = 0;
2376 static const gchar *tags[] = { NULL };
2378 if (g_once_init_enter (&type)) {
2379 GType _type = gst_meta_api_type_register ("GstParentBufferMetaAPI", tags);
2380 g_once_init_leave (&type, _type);
2387 * gst_parent_buffer_meta_get_info:
2389 * Get the global #GstMetaInfo describing the #GstParentBufferMeta meta.
2391 * Returns: (transfer none): The #GstMetaInfo
2396 gst_parent_buffer_meta_get_info (void)
2398 static const GstMetaInfo *meta_info = NULL;
2400 if (g_once_init_enter (&meta_info)) {
2401 const GstMetaInfo *meta =
2402 gst_meta_register (gst_parent_buffer_meta_api_get_type (),
2403 "GstParentBufferMeta",
2404 sizeof (GstParentBufferMeta),
2405 (GstMetaInitFunction) _gst_parent_buffer_meta_init,
2406 (GstMetaFreeFunction) _gst_parent_buffer_meta_free,
2407 _gst_parent_buffer_meta_transform);
2408 g_once_init_leave (&meta_info, meta);