/* GStreamer
* Copyright (C) 2004 Benjamin Otte <otte@gnome.org>
* 2005 Wim Taymans <wim@fluendo.com>
*
* 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.
*/
/**
* SECTION:gstadapter
* @title: GstAdapter
* @short_description: adapts incoming data on a sink pad into chunks of N bytes
*
* This class is for elements that receive buffers in an undesired size.
* While for example raw video contains one image per buffer, the same is not
* true for a lot of other formats, especially those that come directly from
* a file. So if you have undefined buffer sizes and require a specific size,
* this object is for you.
*
* An adapter is created with gst_adapter_new(). It can be freed again with
* g_object_unref().
*
* The theory of operation is like this: All buffers received are put
* into the adapter using gst_adapter_push() and the data is then read back
* in chunks of the desired size using gst_adapter_map()/gst_adapter_unmap()
* and/or gst_adapter_copy(). After the data has been processed, it is freed
* using gst_adapter_unmap().
*
* Other methods such as gst_adapter_take() and gst_adapter_take_buffer()
* combine gst_adapter_map() and gst_adapter_unmap() in one method and are
* potentially more convenient for some use cases.
*
* For example, a sink pad's chain function that needs to pass data to a library
* in 512-byte chunks could be implemented like this:
* |[<!-- language="C" -->
* static GstFlowReturn
* sink_pad_chain (GstPad *pad, GstObject *parent, GstBuffer *buffer)
* {
* MyElement *this;
* GstAdapter *adapter;
* GstFlowReturn ret = GST_FLOW_OK;
*
* this = MY_ELEMENT (parent);
*
* adapter = this->adapter;
*
* // put buffer into adapter
* gst_adapter_push (adapter, buffer);
*
* // while we can read out 512 bytes, process them
* while (gst_adapter_available (adapter) >= 512 && ret == GST_FLOW_OK) {
* const guint8 *data = gst_adapter_map (adapter, 512);
* // use flowreturn as an error value
* ret = my_library_foo (data);
* gst_adapter_unmap (adapter);
* gst_adapter_flush (adapter, 512);
* }
* return ret;
* }
* ]|
*
* For another example, a simple element inside GStreamer that uses #GstAdapter
* is the libvisual element.
*
* An element using #GstAdapter in its sink pad chain function should ensure that
* when the FLUSH_STOP event is received, that any queued data is cleared using
* gst_adapter_clear(). Data should also be cleared or processed on EOS and
* when changing state from %GST_STATE_PAUSED to %GST_STATE_READY.
*
* Also check the GST_BUFFER_FLAG_DISCONT flag on the buffer. Some elements might
* need to clear the adapter after a discontinuity.
*
* The adapter will keep track of the timestamps of the buffers
* that were pushed. The last seen timestamp before the current position
* can be queried with gst_adapter_prev_pts(). This function can
* optionally return the number of bytes between the start of the buffer that
* carried the timestamp and the current adapter position. The distance is
* useful when dealing with, for example, raw audio samples because it allows
* you to calculate the timestamp of the current adapter position by using the
* last seen timestamp and the amount of bytes since. Additionally, the
* gst_adapter_prev_pts_at_offset() can be used to determine the last
* seen timestamp at a particular offset in the adapter.
*
* The adapter will also keep track of the offset of the buffers
* (#GST_BUFFER_OFFSET) that were pushed. The last seen offset before the
* current position can be queried with gst_adapter_prev_offset(). This function
* can optionally return the number of bytes between the start of the buffer
* that carried the offset and the current adapter position.
*
* Additionally the adapter also keeps track of the PTS, DTS and buffer offset
* at the last discontinuity, which can be retrieved with
* gst_adapter_pts_at_discont(), gst_adapter_dts_at_discont() and
* gst_adapter_offset_at_discont(). The number of bytes that were consumed
* since then can be queried with gst_adapter_distance_from_discont().
*
* A last thing to note is that while #GstAdapter is pretty optimized,
* merging buffers still might be an operation that requires a malloc() and
* memcpy() operation, and these operations are not the fastest. Because of
* this, some functions like gst_adapter_available_fast() are provided to help
* speed up such cases should you want to. To avoid repeated memory allocations,
* gst_adapter_copy() can be used to copy data into a (statically allocated)
* user provided buffer.
*
* #GstAdapter is not MT safe. All operations on an adapter must be serialized by
* the caller. This is not normally a problem, however, as the normal use case
* of #GstAdapter is inside one pad's chain function, in which case access is
* serialized via the pad's STREAM_LOCK.
*
* Note that gst_adapter_push() takes ownership of the buffer passed. Use
* gst_buffer_ref() before pushing it into the adapter if you still want to
* access the buffer later. The adapter will never modify the data in the
* buffer pushed in it.
*/
#include <gst/gst_private.h>
#include "gstadapter.h"
#include <string.h>
/* default size for the assembled data buffer */
#define DEFAULT_SIZE 4096
static void gst_adapter_flush_unchecked (GstAdapter * adapter, gsize flush);
GST_DEBUG_CATEGORY_STATIC (gst_adapter_debug);
#define GST_CAT_DEFAULT gst_adapter_debug
struct _GstAdapter
{
GObject object;
/*< private > */
GSList *buflist;
GSList *buflist_end;
gsize size;
gsize skip;
guint count;
/* we keep state of assembled pieces */
gpointer assembled_data;
gsize assembled_size;
gsize assembled_len;
GstClockTime pts;
guint64 pts_distance;
GstClockTime dts;
guint64 dts_distance;
guint64 offset;
guint64 offset_distance;
gsize scan_offset;
GSList *scan_entry;
GstClockTime pts_at_discont;
GstClockTime dts_at_discont;
guint64 offset_at_discont;
guint64 distance_from_discont;
GstMapInfo info;
};
struct _GstAdapterClass
{
GObjectClass parent_class;
};
#define _do_init \
GST_DEBUG_CATEGORY_INIT (gst_adapter_debug, "adapter", 0, "object to splice and merge buffers to desired size")
#define gst_adapter_parent_class parent_class
G_DEFINE_TYPE_WITH_CODE (GstAdapter, gst_adapter, G_TYPE_OBJECT, _do_init);
static void gst_adapter_dispose (GObject * object);
static void gst_adapter_finalize (GObject * object);
static void
gst_adapter_class_init (GstAdapterClass * klass)
{
GObjectClass *object = G_OBJECT_CLASS (klass);
object->dispose = gst_adapter_dispose;
object->finalize = gst_adapter_finalize;
}
static void
gst_adapter_init (GstAdapter * adapter)
{
adapter->assembled_data = g_malloc (DEFAULT_SIZE);
adapter->assembled_size = DEFAULT_SIZE;
adapter->pts = GST_CLOCK_TIME_NONE;
adapter->pts_distance = 0;
adapter->dts = GST_CLOCK_TIME_NONE;
adapter->dts_distance = 0;
adapter->offset = GST_BUFFER_OFFSET_NONE;
adapter->offset_distance = 0;
adapter->pts_at_discont = GST_CLOCK_TIME_NONE;
adapter->dts_at_discont = GST_CLOCK_TIME_NONE;
adapter->offset_at_discont = GST_BUFFER_OFFSET_NONE;
adapter->distance_from_discont = 0;
}
static void
gst_adapter_dispose (GObject * object)
{
GstAdapter *adapter = GST_ADAPTER (object);
gst_adapter_clear (adapter);
GST_CALL_PARENT (G_OBJECT_CLASS, dispose, (object));
}
static void
gst_adapter_finalize (GObject * object)
{
GstAdapter *adapter = GST_ADAPTER (object);
g_free (adapter->assembled_data);
GST_CALL_PARENT (G_OBJECT_CLASS, finalize, (object));
}
/**
* gst_adapter_new:
*
* Creates a new #GstAdapter. Free with g_object_unref().
*
* Returns: (transfer full): a new #GstAdapter
*/
GstAdapter *
gst_adapter_new (void)
{
return g_object_new (GST_TYPE_ADAPTER, NULL);
}
/**
* gst_adapter_clear:
* @adapter: a #GstAdapter
*
* Removes all buffers from @adapter.
*/
void
gst_adapter_clear (GstAdapter * adapter)
{
g_return_if_fail (GST_IS_ADAPTER (adapter));
if (adapter->info.memory)
gst_adapter_unmap (adapter);
g_slist_foreach (adapter->buflist, (GFunc) gst_mini_object_unref, NULL);
g_slist_free (adapter->buflist);
adapter->buflist = NULL;
adapter->buflist_end = NULL;
adapter->count = 0;
adapter->size = 0;
adapter->skip = 0;
adapter->assembled_len = 0;
adapter->pts = GST_CLOCK_TIME_NONE;
adapter->pts_distance = 0;
adapter->dts = GST_CLOCK_TIME_NONE;
adapter->dts_distance = 0;
adapter->offset = GST_BUFFER_OFFSET_NONE;
adapter->offset_distance = 0;
adapter->pts_at_discont = GST_CLOCK_TIME_NONE;
adapter->dts_at_discont = GST_CLOCK_TIME_NONE;
adapter->offset_at_discont = GST_BUFFER_OFFSET_NONE;
adapter->distance_from_discont = 0;
adapter->scan_offset = 0;
adapter->scan_entry = NULL;
}
static inline void
update_timestamps_and_offset (GstAdapter * adapter, GstBuffer * buf)
{
GstClockTime pts, dts;
guint64 offset;
pts = GST_BUFFER_PTS (buf);
if (GST_CLOCK_TIME_IS_VALID (pts)) {
GST_LOG_OBJECT (adapter, "new pts %" GST_TIME_FORMAT, GST_TIME_ARGS (pts));
adapter->pts = pts;
adapter->pts_distance = 0;
}
dts = GST_BUFFER_DTS (buf);
if (GST_CLOCK_TIME_IS_VALID (dts)) {
GST_LOG_OBJECT (adapter, "new dts %" GST_TIME_FORMAT, GST_TIME_ARGS (dts));
adapter->dts = dts;
adapter->dts_distance = 0;
}
offset = GST_BUFFER_OFFSET (buf);
if (offset != GST_BUFFER_OFFSET_NONE) {
GST_LOG_OBJECT (adapter, "new offset %" G_GUINT64_FORMAT, offset);
adapter->offset = offset;
adapter->offset_distance = 0;
}
if (GST_BUFFER_IS_DISCONT (buf)) {
/* Take values as-is (might be NONE) */
adapter->pts_at_discont = pts;
adapter->dts_at_discont = dts;
adapter->offset_at_discont = offset;
adapter->distance_from_discont = 0;
}
}
/* copy data into @dest, skipping @skip bytes from the head buffers */
static void
copy_into_unchecked (GstAdapter * adapter, guint8 * dest, gsize skip,
gsize size)
{
GSList *g;
GstBuffer *buf;
gsize bsize, csize;
/* first step, do skipping */
/* we might well be copying where we were scanning */
if (adapter->scan_entry && (adapter->scan_offset <= skip)) {
g = adapter->scan_entry;
skip -= adapter->scan_offset;
} else {
g = adapter->buflist;
}
buf = g->data;
bsize = gst_buffer_get_size (buf);
while (G_UNLIKELY (skip >= bsize)) {
skip -= bsize;
g = g_slist_next (g);
buf = g->data;
bsize = gst_buffer_get_size (buf);
}
/* copy partial buffer */
csize = MIN (bsize - skip, size);
GST_DEBUG ("bsize %" G_GSIZE_FORMAT ", skip %" G_GSIZE_FORMAT ", csize %"
G_GSIZE_FORMAT, bsize, skip, csize);
GST_CAT_LOG_OBJECT (GST_CAT_PERFORMANCE, adapter, "extract %" G_GSIZE_FORMAT
" bytes", csize);
gst_buffer_extract (buf, skip, dest, csize);
size -= csize;
dest += csize;
/* second step, copy remainder */
while (size > 0) {
g = g_slist_next (g);
buf = g->data;
bsize = gst_buffer_get_size (buf);
if (G_LIKELY (bsize > 0)) {
csize = MIN (bsize, size);
GST_CAT_LOG_OBJECT (GST_CAT_PERFORMANCE, adapter,
"extract %" G_GSIZE_FORMAT " bytes", csize);
gst_buffer_extract (buf, 0, dest, csize);
size -= csize;
dest += csize;
}
}
}
/**
* gst_adapter_push:
* @adapter: a #GstAdapter
* @buf: (transfer full): a #GstBuffer to add to queue in the adapter
*
* Adds the data from @buf to the data stored inside @adapter and takes
* ownership of the buffer.
*/
void
gst_adapter_push (GstAdapter * adapter, GstBuffer * buf)
{
gsize size;
g_return_if_fail (GST_IS_ADAPTER (adapter));
g_return_if_fail (GST_IS_BUFFER (buf));
size = gst_buffer_get_size (buf);
adapter->size += size;
/* Note: merging buffers at this point is premature. */
if (G_UNLIKELY (adapter->buflist == NULL)) {
GST_LOG_OBJECT (adapter, "pushing %p first %" G_GSIZE_FORMAT " bytes",
buf, size);
adapter->buflist = adapter->buflist_end = g_slist_append (NULL, buf);
update_timestamps_and_offset (adapter, buf);
} else {
/* Otherwise append to the end, and advance our end pointer */
GST_LOG_OBJECT (adapter, "pushing %p %" G_GSIZE_FORMAT " bytes at end, "
"size now %" G_GSIZE_FORMAT, buf, size, adapter->size);
adapter->buflist_end = g_slist_append (adapter->buflist_end, buf);
adapter->buflist_end = g_slist_next (adapter->buflist_end);
}
++adapter->count;
}
#if 0
/* Internal method only. Tries to merge buffers at the head of the queue
* to form a single larger buffer of size 'size'.
*
* Returns %TRUE if it managed to merge anything.
*/
static gboolean
gst_adapter_try_to_merge_up (GstAdapter * adapter, gsize size)
{
GstBuffer *cur, *head;
GSList *g;
gboolean ret = FALSE;
gsize hsize;
g = adapter->buflist;
if (g == NULL)
return FALSE;
head = g->data;
hsize = gst_buffer_get_size (head);
/* Remove skipped part from the buffer (otherwise the buffer might grow indefinitely) */
head = gst_buffer_make_writable (head);
gst_buffer_resize (head, adapter->skip, hsize - adapter->skip);
hsize -= adapter->skip;
adapter->skip = 0;
g->data = head;
g = g_slist_next (g);
while (g != NULL && hsize < size) {
cur = g->data;
/* Merge the head buffer and the next in line */
GST_LOG_OBJECT (adapter, "Merging buffers of size %" G_GSIZE_FORMAT " & %"
G_GSIZE_FORMAT " in search of target %" G_GSIZE_FORMAT,
hsize, gst_buffer_get_size (cur), size);
head = gst_buffer_append (head, cur);
hsize = gst_buffer_get_size (head);
ret = TRUE;
/* Delete the front list item, and store our new buffer in the 2nd list
* item */
adapter->buflist = g_slist_delete_link (adapter->buflist, adapter->buflist);
g->data = head;
/* invalidate scan position */
adapter->scan_offset = 0;
adapter->scan_entry = NULL;
g = g_slist_next (g);
}
return ret;
}
#endif
/**
* gst_adapter_map:
* @adapter: a #GstAdapter
* @size: the number of bytes to map/peek
*
* Gets the first @size bytes stored in the @adapter. The returned pointer is
* valid until the next function is called on the adapter.
*
* Note that setting the returned pointer as the data of a #GstBuffer is
* incorrect for general-purpose plugins. The reason is that if a downstream
* element stores the buffer so that it has access to it outside of the bounds
* of its chain function, the buffer will have an invalid data pointer after
* your element flushes the bytes. In that case you should use
* gst_adapter_take(), which returns a freshly-allocated buffer that you can set
* as #GstBuffer memory or the potentially more performant
* gst_adapter_take_buffer().
*
* Returns %NULL if @size bytes are not available.
*
* Returns: (transfer none) (array length=size) (element-type guint8) (nullable):
* a pointer to the first @size bytes of data, or %NULL
*/
gconstpointer
gst_adapter_map (GstAdapter * adapter, gsize size)
{
GstBuffer *cur;
gsize skip, csize;
gsize toreuse, tocopy;
guint8 *data;
g_return_val_if_fail (GST_IS_ADAPTER (adapter), NULL);
g_return_val_if_fail (size > 0, NULL);
if (adapter->info.memory)
gst_adapter_unmap (adapter);
/* we don't have enough data, return NULL. This is unlikely
* as one usually does an _available() first instead of peeking a
* random size. */
if (G_UNLIKELY (size > adapter->size))
return NULL;
/* we have enough assembled data, return it */
if (adapter->assembled_len >= size)
return adapter->assembled_data;
#if 0
do {
#endif
cur = adapter->buflist->data;
skip = adapter->skip;
csize = gst_buffer_get_size (cur);
if (csize >= size + skip) {
if (!gst_buffer_map (cur, &adapter->info, GST_MAP_READ))
return FALSE;
return (guint8 *) adapter->info.data + skip;
}
/* We may be able to efficiently merge buffers in our pool to
* gather a big enough chunk to return it from the head buffer directly */
#if 0
} while (gst_adapter_try_to_merge_up (adapter, size));
#endif
/* see how much data we can reuse from the assembled memory and how much
* we need to copy */
toreuse = adapter->assembled_len;
tocopy = size - toreuse;
/* Gonna need to copy stuff out */
if (G_UNLIKELY (adapter->assembled_size < size)) {
adapter->assembled_size = (size / DEFAULT_SIZE + 1) * DEFAULT_SIZE;
GST_DEBUG_OBJECT (adapter, "resizing internal buffer to %" G_GSIZE_FORMAT,
adapter->assembled_size);
if (toreuse == 0) {
GST_CAT_DEBUG (GST_CAT_PERFORMANCE, "alloc new buffer");
/* no g_realloc to avoid a memcpy that is not desired here since we are
* not going to reuse any data here */
g_free (adapter->assembled_data);
adapter->assembled_data = g_malloc (adapter->assembled_size);
} else {
/* we are going to reuse all data, realloc then */
GST_CAT_DEBUG (GST_CAT_PERFORMANCE, "reusing %" G_GSIZE_FORMAT " bytes",
toreuse);
adapter->assembled_data =
g_realloc (adapter->assembled_data, adapter->assembled_size);
}
}
GST_CAT_DEBUG (GST_CAT_PERFORMANCE, "copy remaining %" G_GSIZE_FORMAT
" bytes from adapter", tocopy);
data = adapter->assembled_data;
copy_into_unchecked (adapter, data + toreuse, skip + toreuse, tocopy);
adapter->assembled_len = size;
return adapter->assembled_data;
}
/**
* gst_adapter_unmap:
* @adapter: a #GstAdapter
*
* Releases the memory obtained with the last gst_adapter_map().
*/
void
gst_adapter_unmap (GstAdapter * adapter)
{
g_return_if_fail (GST_IS_ADAPTER (adapter));
if (adapter->info.memory) {
GstBuffer *cur = adapter->buflist->data;
GST_LOG_OBJECT (adapter, "unmap memory buffer %p", cur);
gst_buffer_unmap (cur, &adapter->info);
adapter->info.memory = NULL;
}
}
/**
* gst_adapter_copy: (skip)
* @adapter: a #GstAdapter
* @dest: (out caller-allocates) (array length=size) (element-type guint8):
* the memory to copy into
* @offset: the bytes offset in the adapter to start from
* @size: the number of bytes to copy
*
* Copies @size bytes of data starting at @offset out of the buffers
* contained in #GstAdapter into an array @dest provided by the caller.
*
* The array @dest should be large enough to contain @size bytes.
* The user should check that the adapter has (@offset + @size) bytes
* available before calling this function.
*/
void
gst_adapter_copy (GstAdapter * adapter, gpointer dest, gsize offset, gsize size)
{
g_return_if_fail (GST_IS_ADAPTER (adapter));
g_return_if_fail (size > 0);
g_return_if_fail (offset + size <= adapter->size);
copy_into_unchecked (adapter, dest, offset + adapter->skip, size);
}
/**
* gst_adapter_copy_bytes: (rename-to gst_adapter_copy)
* @adapter: a #GstAdapter
* @offset: the bytes offset in the adapter to start from
* @size: the number of bytes to copy
*
* Similar to gst_adapter_copy, but more suitable for language bindings. @size
* bytes of data starting at @offset will be copied out of the buffers contained
* in @adapter and into a new #GBytes structure which is returned. Depending on
* the value of the @size argument an empty #GBytes structure may be returned.
*
* Returns: (transfer full): A new #GBytes structure containing the copied data.
*
* Since: 1.4
*/
GBytes *
gst_adapter_copy_bytes (GstAdapter * adapter, gsize offset, gsize size)
{
gpointer data;
data = g_malloc (size);
gst_adapter_copy (adapter, data, offset, size);
return g_bytes_new_take (data, size);
}
/*Flushes the first @flush bytes in the @adapter*/
static void
gst_adapter_flush_unchecked (GstAdapter * adapter, gsize flush)
{
GstBuffer *cur;
gsize size;
GSList *g;
GST_LOG_OBJECT (adapter, "flushing %" G_GSIZE_FORMAT " bytes", flush);
if (adapter->info.memory)
gst_adapter_unmap (adapter);
/* clear state */
adapter->size -= flush;
adapter->assembled_len = 0;
/* take skip into account */
flush += adapter->skip;
/* distance is always at least the amount of skipped bytes */
adapter->pts_distance -= adapter->skip;
adapter->dts_distance -= adapter->skip;
adapter->offset_distance -= adapter->skip;
adapter->distance_from_discont -= adapter->skip;
g = adapter->buflist;
cur = g->data;
size = gst_buffer_get_size (cur);
while (flush >= size) {
/* can skip whole buffer */
GST_LOG_OBJECT (adapter, "flushing out head buffer");
adapter->pts_distance += size;
adapter->dts_distance += size;
adapter->offset_distance += size;
adapter->distance_from_discont += size;
flush -= size;
gst_buffer_unref (cur);
g = g_slist_delete_link (g, g);
--adapter->count;
if (G_UNLIKELY (g == NULL)) {
GST_LOG_OBJECT (adapter, "adapter empty now");
adapter->buflist_end = NULL;
break;
}
/* there is a new head buffer, update the timestamps */
cur = g->data;
update_timestamps_and_offset (adapter, cur);
size = gst_buffer_get_size (cur);
}
adapter->buflist = g;
/* account for the remaining bytes */
adapter->skip = flush;
adapter->pts_distance += flush;
adapter->dts_distance += flush;
adapter->offset_distance += flush;
adapter->distance_from_discont += flush;
/* invalidate scan position */
adapter->scan_offset = 0;
adapter->scan_entry = NULL;
}
/**
* gst_adapter_flush:
* @adapter: a #GstAdapter
* @flush: the number of bytes to flush
*
* Flushes the first @flush bytes in the @adapter. The caller must ensure that
* at least this many bytes are available.
*
* See also: gst_adapter_map(), gst_adapter_unmap()
*/
void
gst_adapter_flush (GstAdapter * adapter, gsize flush)
{
g_return_if_fail (GST_IS_ADAPTER (adapter));
g_return_if_fail (flush <= adapter->size);
/* flushing out 0 bytes will do nothing */
if (G_UNLIKELY (flush == 0))
return;
gst_adapter_flush_unchecked (adapter, flush);
}
/* internal function, nbytes should be flushed if needed after calling this function */
static guint8 *
gst_adapter_get_internal (GstAdapter * adapter, gsize nbytes)
{
guint8 *data;
gsize toreuse, tocopy;
/* see how much data we can reuse from the assembled memory and how much
* we need to copy */
toreuse = MIN (nbytes, adapter->assembled_len);
tocopy = nbytes - toreuse;
/* find memory to return */
if (adapter->assembled_size >= nbytes && toreuse > 0) {
/* we reuse already allocated memory but only when we're going to reuse
* something from it because else we are worse than the malloc and copy
* case below */
GST_LOG_OBJECT (adapter, "reusing %" G_GSIZE_FORMAT " bytes of assembled"
" data", toreuse);
/* we have enough free space in the assembled array */
data = adapter->assembled_data;
/* flush after this function should set the assembled_size to 0 */
adapter->assembled_data = g_malloc (adapter->assembled_size);
} else {
GST_LOG_OBJECT (adapter, "allocating %" G_GSIZE_FORMAT " bytes", nbytes);
/* not enough bytes in the assembled array, just allocate new space */
data = g_malloc (nbytes);
/* reuse what we can from the already assembled data */
if (toreuse) {
GST_LOG_OBJECT (adapter, "reusing %" G_GSIZE_FORMAT " bytes", toreuse);
GST_CAT_LOG_OBJECT (GST_CAT_PERFORMANCE, adapter,
"memcpy %" G_GSIZE_FORMAT " bytes", toreuse);
memcpy (data, adapter->assembled_data, toreuse);
}
}
if (tocopy) {
/* copy the remaining data */
copy_into_unchecked (adapter, toreuse + data, toreuse + adapter->skip,
tocopy);
}
return data;
}
/**
* gst_adapter_take:
* @adapter: a #GstAdapter
* @nbytes: the number of bytes to take
*
* Returns a freshly allocated buffer containing the first @nbytes bytes of the
* @adapter. The returned bytes will be flushed from the adapter.
*
* Caller owns returned value. g_free after usage.
*
* Free-function: g_free
*
* Returns: (transfer full) (array length=nbytes) (element-type guint8) (nullable):
* oven-fresh hot data, or %NULL if @nbytes bytes are not available
*/
gpointer
gst_adapter_take (GstAdapter * adapter, gsize nbytes)
{
gpointer data;
g_return_val_if_fail (GST_IS_ADAPTER (adapter), NULL);
g_return_val_if_fail (nbytes > 0, NULL);
/* we don't have enough data, return NULL. This is unlikely
* as one usually does an _available() first instead of peeking a
* random size. */
if (G_UNLIKELY (nbytes > adapter->size))
return NULL;
data = gst_adapter_get_internal (adapter, nbytes);
gst_adapter_flush_unchecked (adapter, nbytes);
return data;
}
/**
* gst_adapter_get_buffer_fast:
* @adapter: a #GstAdapter
* @nbytes: the number of bytes to get
*
* Returns a #GstBuffer containing the first @nbytes of the @adapter, but
* does not flush them from the adapter. See gst_adapter_take_buffer_fast()
* for details.
*
* Caller owns a reference to the returned buffer. gst_buffer_unref() after
* usage.
*
* Free-function: gst_buffer_unref
*
* Returns: (transfer full) (nullable): a #GstBuffer containing the first
* @nbytes of the adapter, or %NULL if @nbytes bytes are not available.
* gst_buffer_unref() when no longer needed.
*
* Since: 1.6
*/
GstBuffer *
gst_adapter_get_buffer_fast (GstAdapter * adapter, gsize nbytes)
{
GstBuffer *buffer = NULL;
GstBuffer *cur;
GSList *item;
gsize skip;
gsize left = nbytes;
g_return_val_if_fail (GST_IS_ADAPTER (adapter), NULL);
g_return_val_if_fail (nbytes > 0, NULL);
GST_LOG_OBJECT (adapter, "getting buffer of %" G_GSIZE_FORMAT " bytes",
nbytes);
/* we don't have enough data, return NULL. This is unlikely
* as one usually does an _available() first instead of grabbing a
* random size. */
if (G_UNLIKELY (nbytes > adapter->size))
return NULL;
skip = adapter->skip;
cur = adapter->buflist->data;
if (skip == 0 && gst_buffer_get_size (cur) == nbytes) {
GST_LOG_OBJECT (adapter, "providing buffer of %" G_GSIZE_FORMAT " bytes"
" as head buffer", nbytes);
buffer = gst_buffer_ref (cur);
goto done;
}
for (item = adapter->buflist; item && left > 0; item = item->next) {
gsize size, cur_size;
cur = item->data;
cur_size = gst_buffer_get_size (cur);
size = MIN (cur_size - skip, left);
GST_LOG_OBJECT (adapter, "appending %" G_GSIZE_FORMAT " bytes"
" via region copy", size);
if (buffer)
gst_buffer_copy_into (buffer, cur,
GST_BUFFER_COPY_MEMORY | GST_BUFFER_COPY_META, skip, size);
else
buffer = gst_buffer_copy_region (cur, GST_BUFFER_COPY_ALL, skip, size);
skip = 0;
left -= size;
}
done:
return buffer;
}
/**
* gst_adapter_take_buffer_fast:
* @adapter: a #GstAdapter
* @nbytes: the number of bytes to take
*
* Returns a #GstBuffer containing the first @nbytes of the @adapter.
* The returned bytes will be flushed from the adapter. This function
* is potentially more performant than gst_adapter_take_buffer() since
* it can reuse the memory in pushed buffers by subbuffering or
* merging. Unlike gst_adapter_take_buffer(), the returned buffer may
* be composed of multiple non-contiguous #GstMemory objects, no
* copies are made.
*
* Note that no assumptions should be made as to whether certain buffer
* flags such as the DISCONT flag are set on the returned buffer, or not.
* The caller needs to explicitly set or unset flags that should be set or
* unset.
*
* This will also copy over all GstMeta of the input buffers except
* for meta with the %GST_META_FLAG_POOLED flag or with the "memory" tag.
*
* This function can return buffer up to the return value of
* gst_adapter_available() without making copies if possible.
*
* Caller owns a reference to the returned buffer. gst_buffer_unref() after
* usage.
*
* Free-function: gst_buffer_unref
*
* Returns: (transfer full) (nullable): a #GstBuffer containing the first
* @nbytes of the adapter, or %NULL if @nbytes bytes are not available.
* gst_buffer_unref() when no longer needed.
*
* Since: 1.2
*/
GstBuffer *
gst_adapter_take_buffer_fast (GstAdapter * adapter, gsize nbytes)
{
GstBuffer *buffer;
g_return_val_if_fail (GST_IS_ADAPTER (adapter), NULL);
g_return_val_if_fail (nbytes > 0, NULL);
buffer = gst_adapter_get_buffer_fast (adapter, nbytes);
if (buffer)
gst_adapter_flush_unchecked (adapter, nbytes);
return buffer;
}
static gboolean
foreach_metadata (GstBuffer * inbuf, GstMeta ** meta, gpointer user_data)
{
GstBuffer *outbuf = user_data;
const GstMetaInfo *info = (*meta)->info;
gboolean do_copy = FALSE;
if (gst_meta_api_type_has_tag (info->api, _gst_meta_tag_memory)) {
/* never call the transform_meta with memory specific metadata */
GST_DEBUG ("not copying memory specific metadata %s",
g_type_name (info->api));
do_copy = FALSE;
} else {
do_copy = TRUE;
GST_DEBUG ("copying metadata %s", g_type_name (info->api));
}
if (do_copy && info->transform_func) {
GstMetaTransformCopy copy_data = { FALSE, 0, -1 };
GST_DEBUG ("copy metadata %s", g_type_name (info->api));
/* simply copy then */
info->transform_func (outbuf, *meta, inbuf,
_gst_meta_transform_copy, ©_data);
}
return TRUE;
}
/**
* gst_adapter_get_buffer:
* @adapter: a #GstAdapter
* @nbytes: the number of bytes to get
*
* Returns a #GstBuffer containing the first @nbytes of the @adapter, but
* does not flush them from the adapter. See gst_adapter_take_buffer()
* for details.
*
* Caller owns a reference to the returned buffer. gst_buffer_unref() after
* usage.
*
* Free-function: gst_buffer_unref
*
* Returns: (transfer full) (nullable): a #GstBuffer containing the first
* @nbytes of the adapter, or %NULL if @nbytes bytes are not available.
* gst_buffer_unref() when no longer needed.
*
* Since: 1.6
*/
GstBuffer *
gst_adapter_get_buffer (GstAdapter * adapter, gsize nbytes)
{
GstBuffer *buffer;
GstBuffer *cur;
gsize hsize, skip;
guint8 *data;
g_return_val_if_fail (GST_IS_ADAPTER (adapter), NULL);
g_return_val_if_fail (nbytes > 0, NULL);
GST_LOG_OBJECT (adapter, "getting buffer of %" G_GSIZE_FORMAT " bytes",
nbytes);
/* we don't have enough data, return NULL. This is unlikely
* as one usually does an _available() first instead of grabbing a
* random size. */
if (G_UNLIKELY (nbytes > adapter->size))
return NULL;
cur = adapter->buflist->data;
skip = adapter->skip;
hsize = gst_buffer_get_size (cur);
/* our head buffer has enough data left, return it */
if (skip == 0 && hsize == nbytes) {
GST_LOG_OBJECT (adapter, "providing buffer of %" G_GSIZE_FORMAT " bytes"
" as head buffer", nbytes);
buffer = gst_buffer_ref (cur);
goto done;
} else if (hsize >= nbytes + skip) {
GST_LOG_OBJECT (adapter, "providing buffer of %" G_GSIZE_FORMAT " bytes"
" via region copy", nbytes);
buffer = gst_buffer_copy_region (cur, GST_BUFFER_COPY_ALL, skip, nbytes);
goto done;
}
#if 0
if (gst_adapter_try_to_merge_up (adapter, nbytes)) {
/* Merged something, let's try again for sub-buffering */
cur = adapter->buflist->data;
skip = adapter->skip;
if (gst_buffer_get_size (cur) >= nbytes + skip) {
GST_LOG_OBJECT (adapter, "providing buffer of %" G_GSIZE_FORMAT " bytes"
" via sub-buffer", nbytes);
buffer = gst_buffer_copy_region (cur, GST_BUFFER_COPY_ALL, skip, nbytes);
goto done;
}
}
#endif
data = gst_adapter_get_internal (adapter, nbytes);
buffer = gst_buffer_new_wrapped (data, nbytes);
{
GSList *g;
GstBuffer *cur;
gsize read_offset = 0;
g = adapter->buflist;
while (g && read_offset < nbytes + adapter->skip) {
cur = g->data;
gst_buffer_foreach_meta (cur, foreach_metadata, buffer);
read_offset += gst_buffer_get_size (cur);
g = g_slist_next (g);
}
}
done:
return buffer;
}
/**
* gst_adapter_take_buffer:
* @adapter: a #GstAdapter
* @nbytes: the number of bytes to take
*
* Returns a #GstBuffer containing the first @nbytes bytes of the
* @adapter. The returned bytes will be flushed from the adapter.
* This function is potentially more performant than
* gst_adapter_take() since it can reuse the memory in pushed buffers
* by subbuffering or merging. This function will always return a
* buffer with a single memory region.
*
* Note that no assumptions should be made as to whether certain buffer
* flags such as the DISCONT flag are set on the returned buffer, or not.
* The caller needs to explicitly set or unset flags that should be set or
* unset.
*
* Since 1.6 this will also copy over all GstMeta of the input buffers except
* for meta with the %GST_META_FLAG_POOLED flag or with the "memory" tag.
*
* Caller owns a reference to the returned buffer. gst_buffer_unref() after
* usage.
*
* Free-function: gst_buffer_unref
*
* Returns: (transfer full) (nullable): a #GstBuffer containing the first
* @nbytes of the adapter, or %NULL if @nbytes bytes are not available.
* gst_buffer_unref() when no longer needed.
*/
GstBuffer *
gst_adapter_take_buffer (GstAdapter * adapter, gsize nbytes)
{
GstBuffer *buffer;
g_return_val_if_fail (GST_IS_ADAPTER (adapter), NULL);
g_return_val_if_fail (nbytes > 0, NULL);
buffer = gst_adapter_get_buffer (adapter, nbytes);
if (buffer)
gst_adapter_flush_unchecked (adapter, nbytes);
return buffer;
}
/**
* gst_adapter_take_list:
* @adapter: a #GstAdapter
* @nbytes: the number of bytes to take
*
* Returns a #GList of buffers containing the first @nbytes bytes of the
* @adapter. The returned bytes will be flushed from the adapter.
* When the caller can deal with individual buffers, this function is more
* performant because no memory should be copied.
*
* Caller owns returned list and contained buffers. gst_buffer_unref() each
* buffer in the list before freeing the list after usage.
*
* Returns: (element-type Gst.Buffer) (transfer full) (nullable): a #GList of
* buffers containing the first @nbytes of the adapter, or %NULL if @nbytes
* bytes are not available
*/
GList *
gst_adapter_take_list (GstAdapter * adapter, gsize nbytes)
{
GQueue queue = G_QUEUE_INIT;
GstBuffer *cur;
gsize hsize, skip, cur_size;
g_return_val_if_fail (GST_IS_ADAPTER (adapter), NULL);
g_return_val_if_fail (nbytes <= adapter->size, NULL);
GST_LOG_OBJECT (adapter, "taking %" G_GSIZE_FORMAT " bytes", nbytes);
while (nbytes > 0) {
cur = adapter->buflist->data;
skip = adapter->skip;
cur_size = gst_buffer_get_size (cur);
hsize = MIN (nbytes, cur_size - skip);
cur = gst_adapter_take_buffer (adapter, hsize);
g_queue_push_tail (&queue, cur);
nbytes -= hsize;
}
return queue.head;
}
/**
* gst_adapter_get_list:
* @adapter: a #GstAdapter
* @nbytes: the number of bytes to get
*
* Returns a #GList of buffers containing the first @nbytes bytes of the
* @adapter, but does not flush them from the adapter. See
* gst_adapter_take_list() for details.
*
* Caller owns returned list and contained buffers. gst_buffer_unref() each
* buffer in the list before freeing the list after usage.
*
* Returns: (element-type Gst.Buffer) (transfer full) (nullable): a #GList of
* buffers containing the first @nbytes of the adapter, or %NULL if @nbytes
* bytes are not available
*
* Since: 1.6
*/
GList *
gst_adapter_get_list (GstAdapter * adapter, gsize nbytes)
{
GQueue queue = G_QUEUE_INIT;
GstBuffer *cur, *buffer;
gsize hsize, skip, cur_size;
GSList *g = NULL;
g_return_val_if_fail (GST_IS_ADAPTER (adapter), NULL);
g_return_val_if_fail (nbytes <= adapter->size, NULL);
GST_LOG_OBJECT (adapter, "getting %" G_GSIZE_FORMAT " bytes", nbytes);
g = adapter->buflist;
skip = adapter->skip;
while (nbytes > 0) {
cur = g->data;
cur_size = gst_buffer_get_size (cur);
hsize = MIN (nbytes, cur_size - skip);
if (skip == 0 && cur_size == hsize) {
GST_LOG_OBJECT (adapter,
"inserting a buffer of %" G_GSIZE_FORMAT " bytes", hsize);
buffer = gst_buffer_ref (cur);
} else {
GST_LOG_OBJECT (adapter, "inserting a buffer of %" G_GSIZE_FORMAT " bytes"
" via region copy", hsize);
buffer = gst_buffer_copy_region (cur, GST_BUFFER_COPY_ALL, skip, hsize);
}
g_queue_push_tail (&queue, buffer);
nbytes -= hsize;
skip = 0;
g = g_slist_next (g);
}
return queue.head;
}
/**
* gst_adapter_take_buffer_list:
* @adapter: a #GstAdapter
* @nbytes: the number of bytes to take
*
* Returns a #GstBufferList of buffers containing the first @nbytes bytes of
* the @adapter. The returned bytes will be flushed from the adapter.
* When the caller can deal with individual buffers, this function is more
* performant because no memory should be copied.
*
* Caller owns the returned list. Call gst_buffer_list_unref() to free
* the list after usage.
*
* Returns: (transfer full) (nullable): a #GstBufferList of buffers containing
* the first @nbytes of the adapter, or %NULL if @nbytes bytes are not
* available
*
* Since: 1.6
*/
GstBufferList *
gst_adapter_take_buffer_list (GstAdapter * adapter, gsize nbytes)
{
GstBufferList *buffer_list;
GstBuffer *cur;
gsize hsize, skip, cur_size;
guint n_bufs;
g_return_val_if_fail (GST_IS_ADAPTER (adapter), NULL);
if (nbytes > adapter->size)
return NULL;
GST_LOG_OBJECT (adapter, "taking %" G_GSIZE_FORMAT " bytes", nbytes);
/* try to create buffer list with sufficient size, so no resize is done later */
if (adapter->count < 64)
n_bufs = adapter->count;
else
n_bufs = (adapter->count * nbytes * 1.2 / adapter->size) + 1;
buffer_list = gst_buffer_list_new_sized (n_bufs);
while (nbytes > 0) {
cur = adapter->buflist->data;
skip = adapter->skip;
cur_size = gst_buffer_get_size (cur);
hsize = MIN (nbytes, cur_size - skip);
gst_buffer_list_add (buffer_list, gst_adapter_take_buffer (adapter, hsize));
nbytes -= hsize;
}
return buffer_list;
}
/**
* gst_adapter_get_buffer_list:
* @adapter: a #GstAdapter
* @nbytes: the number of bytes to get
*
* Returns a #GstBufferList of buffers containing the first @nbytes bytes of
* the @adapter but does not flush them from the adapter. See
* gst_adapter_take_buffer_list() for details.
*
* Caller owns the returned list. Call gst_buffer_list_unref() to free
* the list after usage.
*
* Returns: (transfer full) (nullable): a #GstBufferList of buffers containing
* the first @nbytes of the adapter, or %NULL if @nbytes bytes are not
* available
*
* Since: 1.6
*/
GstBufferList *
gst_adapter_get_buffer_list (GstAdapter * adapter, gsize nbytes)
{
GstBufferList *buffer_list;
GstBuffer *cur, *buffer;
gsize hsize, skip, cur_size;
guint n_bufs;
GSList *g = NULL;
g_return_val_if_fail (GST_IS_ADAPTER (adapter), NULL);
if (nbytes > adapter->size)
return NULL;
GST_LOG_OBJECT (adapter, "getting %" G_GSIZE_FORMAT " bytes", nbytes);
/* try to create buffer list with sufficient size, so no resize is done later */
if (adapter->count < 64)
n_bufs = adapter->count;
else
n_bufs = (adapter->count * nbytes * 1.2 / adapter->size) + 1;
buffer_list = gst_buffer_list_new_sized (n_bufs);
g = adapter->buflist;
skip = adapter->skip;
while (nbytes > 0) {
cur = g->data;
cur_size = gst_buffer_get_size (cur);
hsize = MIN (nbytes, cur_size - skip);
if (skip == 0 && cur_size == hsize) {
GST_LOG_OBJECT (adapter,
"inserting a buffer of %" G_GSIZE_FORMAT " bytes", hsize);
buffer = gst_buffer_ref (cur);
} else {
GST_LOG_OBJECT (adapter, "inserting a buffer of %" G_GSIZE_FORMAT " bytes"
" via region copy", hsize);
buffer = gst_buffer_copy_region (cur, GST_BUFFER_COPY_ALL, skip, hsize);
}
gst_buffer_list_add (buffer_list, buffer);
nbytes -= hsize;
skip = 0;
g = g_slist_next (g);
}
return buffer_list;
}
/**
* gst_adapter_available:
* @adapter: a #GstAdapter
*
* Gets the maximum amount of bytes available, that is it returns the maximum
* value that can be supplied to gst_adapter_map() without that function
* returning %NULL.
*
* Returns: number of bytes available in @adapter
*/
gsize
gst_adapter_available (GstAdapter * adapter)
{
g_return_val_if_fail (GST_IS_ADAPTER (adapter), 0);
return adapter->size;
}
/**
* gst_adapter_available_fast:
* @adapter: a #GstAdapter
*
* Gets the maximum number of bytes that are immediately available without
* requiring any expensive operations (like copying the data into a
* temporary buffer).
*
* Returns: number of bytes that are available in @adapter without expensive
* operations
*/
gsize
gst_adapter_available_fast (GstAdapter * adapter)
{
GstBuffer *cur;
gsize size;
GSList *g;
g_return_val_if_fail (GST_IS_ADAPTER (adapter), 0);
/* no data */
if (adapter->size == 0)
return 0;
/* some stuff we already assembled */
if (adapter->assembled_len)
return adapter->assembled_len;
/* take the first non-zero buffer */
g = adapter->buflist;
while (TRUE) {
cur = g->data;
size = gst_buffer_get_size (cur);
if (size != 0)
break;
g = g_slist_next (g);
}
/* we can quickly get the (remaining) data of the first buffer */
return size - adapter->skip;
}
/**
* gst_adapter_get_distance_from_discont:
* @adapter: a #GstAdapter
*
* Get the distance in bytes since the last buffer with the
* %GST_BUFFER_FLAG_DISCONT flag.
*
* The distance will be reset to 0 for all buffers with
* %GST_BUFFER_FLAG_DISCONT on them, and then calculated for all other
* following buffers based on their size.
*
* Since: 1.10
*
* Returns: The offset. Can be %GST_BUFFER_OFFSET_NONE.
*/
guint64
gst_adapter_distance_from_discont (GstAdapter * adapter)
{
return adapter->distance_from_discont;
}
/**
* gst_adapter_offset_at_discont:
* @adapter: a #GstAdapter
*
* Get the offset that was on the last buffer with the GST_BUFFER_FLAG_DISCONT
* flag, or GST_BUFFER_OFFSET_NONE.
*
* Since: 1.10
*
* Returns: The offset at the last discont or GST_BUFFER_OFFSET_NONE.
*/
guint64
gst_adapter_offset_at_discont (GstAdapter * adapter)
{
g_return_val_if_fail (GST_IS_ADAPTER (adapter), GST_BUFFER_OFFSET_NONE);
return adapter->offset_at_discont;
}
/**
* gst_adapter_pts_at_discont:
* @adapter: a #GstAdapter
*
* Get the PTS that was on the last buffer with the GST_BUFFER_FLAG_DISCONT
* flag, or GST_CLOCK_TIME_NONE.
*
* Since: 1.10
*
* Returns: The PTS at the last discont or GST_CLOCK_TIME_NONE.
*/
GstClockTime
gst_adapter_pts_at_discont (GstAdapter * adapter)
{
g_return_val_if_fail (GST_IS_ADAPTER (adapter), GST_CLOCK_TIME_NONE);
return adapter->pts_at_discont;
}
/**
* gst_adapter_dts_at_discont:
* @adapter: a #GstAdapter
*
* Get the DTS that was on the last buffer with the GST_BUFFER_FLAG_DISCONT
* flag, or GST_CLOCK_TIME_NONE.
*
* Since: 1.10
*
* Returns: The DTS at the last discont or GST_CLOCK_TIME_NONE.
*/
GstClockTime
gst_adapter_dts_at_discont (GstAdapter * adapter)
{
g_return_val_if_fail (GST_IS_ADAPTER (adapter), GST_CLOCK_TIME_NONE);
return adapter->dts_at_discont;
}
/**
* gst_adapter_prev_offset:
* @adapter: a #GstAdapter
* @distance: (out) (allow-none): pointer to a location for distance, or %NULL
*
* Get the offset that was before the current byte in the adapter. When
* @distance is given, the amount of bytes between the offset and the current
* position is returned.
*
* The offset is reset to GST_BUFFER_OFFSET_NONE and the distance is set to 0
* when the adapter is first created or when it is cleared. This also means that
* before the first byte with an offset is removed from the adapter, the offset
* and distance returned are GST_BUFFER_OFFSET_NONE and 0 respectively.
*
* Since: 1.10
*
* Returns: The previous seen offset.
*/
guint64
gst_adapter_prev_offset (GstAdapter * adapter, guint64 * distance)
{
g_return_val_if_fail (GST_IS_ADAPTER (adapter), GST_BUFFER_OFFSET_NONE);
if (distance)
*distance = adapter->offset_distance;
return adapter->offset;
}
/**
* gst_adapter_prev_pts:
* @adapter: a #GstAdapter
* @distance: (out) (allow-none): pointer to location for distance, or %NULL
*
* Get the pts that was before the current byte in the adapter. When
* @distance is given, the amount of bytes between the pts and the current
* position is returned.
*
* The pts is reset to GST_CLOCK_TIME_NONE and the distance is set to 0 when
* the adapter is first created or when it is cleared. This also means that before
* the first byte with a pts is removed from the adapter, the pts
* and distance returned are GST_CLOCK_TIME_NONE and 0 respectively.
*
* Returns: The previously seen pts.
*/
GstClockTime
gst_adapter_prev_pts (GstAdapter * adapter, guint64 * distance)
{
g_return_val_if_fail (GST_IS_ADAPTER (adapter), GST_CLOCK_TIME_NONE);
if (distance)
*distance = adapter->pts_distance;
return adapter->pts;
}
/**
* gst_adapter_prev_dts:
* @adapter: a #GstAdapter
* @distance: (out) (allow-none): pointer to location for distance, or %NULL
*
* Get the dts that was before the current byte in the adapter. When
* @distance is given, the amount of bytes between the dts and the current
* position is returned.
*
* The dts is reset to GST_CLOCK_TIME_NONE and the distance is set to 0 when
* the adapter is first created or when it is cleared. This also means that before
* the first byte with a dts is removed from the adapter, the dts
* and distance returned are GST_CLOCK_TIME_NONE and 0 respectively.
*
* Returns: The previously seen dts.
*/
GstClockTime
gst_adapter_prev_dts (GstAdapter * adapter, guint64 * distance)
{
g_return_val_if_fail (GST_IS_ADAPTER (adapter), GST_CLOCK_TIME_NONE);
if (distance)
*distance = adapter->dts_distance;
return adapter->dts;
}
/**
* gst_adapter_prev_pts_at_offset:
* @adapter: a #GstAdapter
* @offset: the offset in the adapter at which to get timestamp
* @distance: (out) (allow-none): pointer to location for distance, or %NULL
*
* Get the pts that was before the byte at offset @offset in the adapter. When
* @distance is given, the amount of bytes between the pts and the current
* position is returned.
*
* The pts is reset to GST_CLOCK_TIME_NONE and the distance is set to 0 when
* the adapter is first created or when it is cleared. This also means that before
* the first byte with a pts is removed from the adapter, the pts
* and distance returned are GST_CLOCK_TIME_NONE and 0 respectively.
*
* Since: 1.2
* Returns: The previously seen pts at given offset.
*/
GstClockTime
gst_adapter_prev_pts_at_offset (GstAdapter * adapter, gsize offset,
guint64 * distance)
{
GstBuffer *cur;
GSList *g;
gsize read_offset = 0;
gsize pts_offset = 0;
GstClockTime pts = adapter->pts;
g_return_val_if_fail (GST_IS_ADAPTER (adapter), GST_CLOCK_TIME_NONE);
g = adapter->buflist;
while (g && read_offset < offset + adapter->skip) {
cur = g->data;
if (GST_CLOCK_TIME_IS_VALID (GST_BUFFER_PTS (cur))) {
pts = GST_BUFFER_PTS (cur);
pts_offset = read_offset;
}
read_offset += gst_buffer_get_size (cur);
g = g_slist_next (g);
}
if (distance)
*distance = adapter->pts_distance + offset - pts_offset;
return pts;
}
/**
* gst_adapter_prev_dts_at_offset:
* @adapter: a #GstAdapter
* @offset: the offset in the adapter at which to get timestamp
* @distance: (out) (allow-none): pointer to location for distance, or %NULL
*
* Get the dts that was before the byte at offset @offset in the adapter. When
* @distance is given, the amount of bytes between the dts and the current
* position is returned.
*
* The dts is reset to GST_CLOCK_TIME_NONE and the distance is set to 0 when
* the adapter is first created or when it is cleared. This also means that before
* the first byte with a dts is removed from the adapter, the dts
* and distance returned are GST_CLOCK_TIME_NONE and 0 respectively.
*
* Since: 1.2
* Returns: The previously seen dts at given offset.
*/
GstClockTime
gst_adapter_prev_dts_at_offset (GstAdapter * adapter, gsize offset,
guint64 * distance)
{
GstBuffer *cur;
GSList *g;
gsize read_offset = 0;
gsize dts_offset = 0;
GstClockTime dts = adapter->dts;
g_return_val_if_fail (GST_IS_ADAPTER (adapter), GST_CLOCK_TIME_NONE);
g = adapter->buflist;
while (g && read_offset < offset + adapter->skip) {
cur = g->data;
if (GST_CLOCK_TIME_IS_VALID (GST_BUFFER_DTS (cur))) {
dts = GST_BUFFER_DTS (cur);
dts_offset = read_offset;
}
read_offset += gst_buffer_get_size (cur);
g = g_slist_next (g);
}
if (distance)
*distance = adapter->dts_distance + offset - dts_offset;
return dts;
}
/**
* gst_adapter_masked_scan_uint32_peek:
* @adapter: a #GstAdapter
* @mask: mask to apply to data before matching against @pattern
* @pattern: pattern to match (after mask is applied)
* @offset: offset into the adapter data from which to start scanning, returns
* the last scanned position.
* @size: number of bytes to scan from offset
* @value: (out) (allow-none): pointer to uint32 to return matching data
*
* Scan for pattern @pattern with applied mask @mask in the adapter data,
* starting from offset @offset. If a match is found, the value that matched
* is returned through @value, otherwise @value is left untouched.
*
* The bytes in @pattern and @mask are interpreted left-to-right, regardless
* of endianness. All four bytes of the pattern must be present in the
* adapter for it to match, even if the first or last bytes are masked out.
*
* It is an error to call this function without making sure that there is
* enough data (offset+size bytes) in the adapter.
*
* Returns: offset of the first match, or -1 if no match was found.
*/
gssize
gst_adapter_masked_scan_uint32_peek (GstAdapter * adapter, guint32 mask,
guint32 pattern, gsize offset, gsize size, guint32 * value)
{
GSList *g;
gsize skip, bsize, i;
guint32 state;
GstMapInfo info;
guint8 *bdata;
GstBuffer *buf;
g_return_val_if_fail (size > 0, -1);
g_return_val_if_fail (offset + size <= adapter->size, -1);
g_return_val_if_fail (((~mask) & pattern) == 0, -1);
/* we can't find the pattern with less than 4 bytes */
if (G_UNLIKELY (size < 4))
return -1;
skip = offset + adapter->skip;
/* first step, do skipping and position on the first buffer */
/* optimistically assume scanning continues sequentially */
if (adapter->scan_entry && (adapter->scan_offset <= skip)) {
g = adapter->scan_entry;
skip -= adapter->scan_offset;
} else {
g = adapter->buflist;
adapter->scan_offset = 0;
adapter->scan_entry = NULL;
}
buf = g->data;
bsize = gst_buffer_get_size (buf);
while (G_UNLIKELY (skip >= bsize)) {
skip -= bsize;
g = g_slist_next (g);
adapter->scan_offset += bsize;
adapter->scan_entry = g;
buf = g->data;
bsize = gst_buffer_get_size (buf);
}
/* get the data now */
if (!gst_buffer_map (buf, &info, GST_MAP_READ))
return -1;
bdata = (guint8 *) info.data + skip;
bsize = info.size - skip;
skip = 0;
/* set the state to something that does not match */
state = ~pattern;
/* now find data */
do {
bsize = MIN (bsize, size);
for (i = 0; i < bsize; i++) {
state = ((state << 8) | bdata[i]);
if (G_UNLIKELY ((state & mask) == pattern)) {
/* we have a match but we need to have skipped at
* least 4 bytes to fill the state. */
if (G_LIKELY (skip + i >= 3)) {
if (G_LIKELY (value))
*value = state;
gst_buffer_unmap (buf, &info);
return offset + skip + i - 3;
}
}
}
size -= bsize;
if (size == 0)
break;
/* nothing found yet, go to next buffer */
skip += bsize;
g = g_slist_next (g);
adapter->scan_offset += info.size;
adapter->scan_entry = g;
gst_buffer_unmap (buf, &info);
buf = g->data;
if (!gst_buffer_map (buf, &info, GST_MAP_READ))
return -1;
bsize = info.size;
bdata = info.data;
} while (TRUE);
gst_buffer_unmap (buf, &info);
/* nothing found */
return -1;
}
/**
* gst_adapter_masked_scan_uint32:
* @adapter: a #GstAdapter
* @mask: mask to apply to data before matching against @pattern
* @pattern: pattern to match (after mask is applied)
* @offset: offset into the adapter data from which to start scanning, returns
* the last scanned position.
* @size: number of bytes to scan from offset
*
* Scan for pattern @pattern with applied mask @mask in the adapter data,
* starting from offset @offset.
*
* The bytes in @pattern and @mask are interpreted left-to-right, regardless
* of endianness. All four bytes of the pattern must be present in the
* adapter for it to match, even if the first or last bytes are masked out.
*
* It is an error to call this function without making sure that there is
* enough data (offset+size bytes) in the adapter.
*
* This function calls gst_adapter_masked_scan_uint32_peek() passing %NULL
* for value.
*
* Returns: offset of the first match, or -1 if no match was found.
*
* Example:
* |[
* // Assume the adapter contains 0x00 0x01 0x02 ... 0xfe 0xff
*
* gst_adapter_masked_scan_uint32 (adapter, 0xffffffff, 0x00010203, 0, 256);
* // -> returns 0
* gst_adapter_masked_scan_uint32 (adapter, 0xffffffff, 0x00010203, 1, 255);
* // -> returns -1
* gst_adapter_masked_scan_uint32 (adapter, 0xffffffff, 0x01020304, 1, 255);
* // -> returns 1
* gst_adapter_masked_scan_uint32 (adapter, 0xffff, 0x0001, 0, 256);
* // -> returns -1
* gst_adapter_masked_scan_uint32 (adapter, 0xffff, 0x0203, 0, 256);
* // -> returns 0
* gst_adapter_masked_scan_uint32 (adapter, 0xffff0000, 0x02030000, 0, 256);
* // -> returns 2
* gst_adapter_masked_scan_uint32 (adapter, 0xffff0000, 0x02030000, 0, 4);
* // -> returns -1
* ]|
*/
gssize
gst_adapter_masked_scan_uint32 (GstAdapter * adapter, guint32 mask,
guint32 pattern, gsize offset, gsize size)
{
return gst_adapter_masked_scan_uint32_peek (adapter, mask, pattern, offset,
size, NULL);
}