gstcollectpads.c

gnash 在pc和嵌入式下开发需要的源码

    GST_WARNING ("cannot remove unknown pad %s:%s", GST_DEBUG_PAD_NAME (pad));
    GST_COLLECT_PADS_PAD_UNLOCK (pads);
    return FALSE;
  }
}

/**
 * gst_collect_pads_is_active:
 * @pads: the collectspads to use
 * @pad: the pad to check
 *
 * Check if a pad is active.
 *
 * This function is currently not implemented.
 *
 * Returns: %TRUE if the pad is active.
 *
 * MT safe.
 */
gboolean
gst_collect_pads_is_active (GstCollectPads * pads, GstPad * pad)
{
  g_return_val_if_fail (pads != NULL, FALSE);
  g_return_val_if_fail (GST_IS_COLLECT_PADS (pads), FALSE);
  g_return_val_if_fail (pad != NULL, FALSE);
  g_return_val_if_fail (GST_IS_PAD (pad), FALSE);

  g_warning ("gst_collect_pads_is_active() is not implemented");

  return FALSE;
}

/**
 * gst_collect_pads_collect:
 * @pads: the collectspads to use
 *
 * Collect data on all pads. This function is usually called
 * from a #GstTask function in an element. 
 *
 * This function is currently not implemented.
 *
 * Returns: #GstFlowReturn of the operation.
 *
 * MT safe.
 */
GstFlowReturn
gst_collect_pads_collect (GstCollectPads * pads)
{
  g_return_val_if_fail (pads != NULL, GST_FLOW_ERROR);
  g_return_val_if_fail (GST_IS_COLLECT_PADS (pads), GST_FLOW_ERROR);

  g_warning ("gst_collect_pads_collect() is not implemented");

  return GST_FLOW_NOT_SUPPORTED;
}

/**
 * gst_collect_pads_collect_range:
 * @pads: the collectspads to use
 * @offset: the offset to collect
 * @length: the length to collect
 *
 * Collect data with @offset and @length on all pads. This function
 * is typically called in the getrange function of an element. 
 *
 * This function is currently not implemented.
 *
 * Returns: #GstFlowReturn of the operation.
 *
 * MT safe.
 */
GstFlowReturn
gst_collect_pads_collect_range (GstCollectPads * pads, guint64 offset,
    guint length)
{
  g_return_val_if_fail (pads != NULL, GST_FLOW_ERROR);
  g_return_val_if_fail (GST_IS_COLLECT_PADS (pads), GST_FLOW_ERROR);

  g_warning ("gst_collect_pads_collect_range() is not implemented");

  return GST_FLOW_NOT_SUPPORTED;
}

/* FIXME, I think this function is used to work around bad behaviour
 * of elements that add pads to themselves without activating them.
 *
 * Must be called with PAD_LOCK.
 */
static void
gst_collect_pads_set_flushing_unlocked (GstCollectPads * pads,
    gboolean flushing)
{
  GSList *walk = NULL;

  /* Update the pads flushing flag */
  for (walk = pads->data; walk; walk = g_slist_next (walk)) {
    GstCollectData *cdata = walk->data;

    if (GST_IS_PAD (cdata->pad)) {
      GST_OBJECT_LOCK (cdata->pad);
      if (flushing)
        GST_PAD_SET_FLUSHING (cdata->pad);
      else
        GST_PAD_UNSET_FLUSHING (cdata->pad);
      cdata->abidata.ABI.flushing = flushing;
      gst_collect_pads_clear (pads, cdata);
      GST_OBJECT_UNLOCK (cdata->pad);
    }
  }
}

/**
 * gst_collect_pads_set_flushing:
 * @pads: the collectspads to use
 * @flushing: desired state of the pads
 *
 * Change the flushing state of all the pads in the collection. No pad
 * is able to accept anymore data when @flushing is %TRUE. Calling this
 * function with @flushing %FALSE makes @pads accept data again.
 *
 * MT safe.
 *
 * Since: 0.10.7.
 */
void
gst_collect_pads_set_flushing (GstCollectPads * pads, gboolean flushing)
{
  g_return_if_fail (pads != NULL);
  g_return_if_fail (GST_IS_COLLECT_PADS (pads));

  GST_COLLECT_PADS_PAD_LOCK (pads);
  gst_collect_pads_set_flushing_unlocked (pads, flushing);
  GST_COLLECT_PADS_PAD_UNLOCK (pads);
}

/**
 * gst_collect_pads_start:
 * @pads: the collectspads to use
 *
 * Starts the processing of data in the collect_pads.
 *
 * MT safe.
 */
void
gst_collect_pads_start (GstCollectPads * pads)
{
  GSList *collected;

  g_return_if_fail (pads != NULL);
  g_return_if_fail (GST_IS_COLLECT_PADS (pads));

  GST_DEBUG_OBJECT (pads, "starting collect pads");

  /* make sure stop and collect cannot be called anymore */
  GST_OBJECT_LOCK (pads);

  /* make pads streamable */
  GST_COLLECT_PADS_PAD_LOCK (pads);

  /* loop over the master pad list and reset the segment */
  collected = pads->abidata.ABI.pad_list;
  for (; collected; collected = g_slist_next (collected)) {
    GstCollectData *data;

    data = collected->data;
    gst_segment_init (&data->segment, GST_FORMAT_UNDEFINED);
  }

  gst_collect_pads_set_flushing_unlocked (pads, FALSE);

  /* Start collect pads */
  pads->started = TRUE;
  GST_COLLECT_PADS_PAD_UNLOCK (pads);
  GST_OBJECT_UNLOCK (pads);
}

/**
 * gst_collect_pads_stop:
 * @pads: the collectspads to use
 *
 * Stops the processing of data in the collect_pads. this function
 * will also unblock any blocking operations.
 *
 * MT safe.
 */
void
gst_collect_pads_stop (GstCollectPads * pads)
{
  GSList *collected;

  g_return_if_fail (pads != NULL);
  g_return_if_fail (GST_IS_COLLECT_PADS (pads));

  GST_DEBUG_OBJECT (pads, "stopping collect pads");

  /* make sure collect and start cannot be called anymore */
  GST_OBJECT_LOCK (pads);

  /* make pads not accept data anymore */
  GST_COLLECT_PADS_PAD_LOCK (pads);
  gst_collect_pads_set_flushing_unlocked (pads, TRUE);

  /* Stop collect pads */
  pads->started = FALSE;
  pads->eospads = 0;
  pads->queuedpads = 0;

  /* loop over the master pad list and flush buffers */
  collected = pads->abidata.ABI.pad_list;
  for (; collected; collected = g_slist_next (collected)) {
    GstCollectData *data;
    GstBuffer **buffer_p;

    data = collected->data;
    if (data->buffer) {
      buffer_p = &data->buffer;
      gst_buffer_replace (buffer_p, NULL);
      data->pos = 0;
    }
    data->abidata.ABI.eos = FALSE;
  }

  GST_COLLECT_PADS_PAD_UNLOCK (pads);
  /* Wake them up so they can end the chain functions. */
  GST_COLLECT_PADS_BROADCAST (pads);

  GST_OBJECT_UNLOCK (pads);
}

/**
 * gst_collect_pads_peek:
 * @pads: the collectspads to peek
 * @data: the data to use
 *
 * Peek at the buffer currently queued in @data. This function
 * should be called with the @pads LOCK held, such as in the callback
 * handler.
 *
 * Returns: The buffer in @data or NULL if no buffer is queued.
 *  should unref the buffer after usage.
 *
 * MT safe.
 */
GstBuffer *
gst_collect_pads_peek (GstCollectPads * pads, GstCollectData * data)
{
  GstBuffer *result;

  g_return_val_if_fail (pads != NULL, NULL);
  g_return_val_if_fail (GST_IS_COLLECT_PADS (pads), NULL);
  g_return_val_if_fail (data != NULL, NULL);

  if ((result = data->buffer))
    gst_buffer_ref (result);

  GST_DEBUG ("Peeking at pad %s:%s: buffer=%p",
      GST_DEBUG_PAD_NAME (data->pad), result);

  return result;
}

/**
 * gst_collect_pads_pop:
 * @pads: the collectspads to pop
 * @data: the data to use
 *
 * Pop the buffer currently queued in @data. This function
 * should be called with the @pads LOCK held, such as in the callback
 * handler.
 *
 * Returns: The buffer in @data or NULL if no buffer was queued.
 *   You should unref the buffer after usage.
 *
 * MT safe.
 */
GstBuffer *
gst_collect_pads_pop (GstCollectPads * pads, GstCollectData * data)
{
  GstBuffer *result;

  g_return_val_if_fail (pads != NULL, NULL);
  g_return_val_if_fail (GST_IS_COLLECT_PADS (pads), NULL);
  g_return_val_if_fail (data != NULL, NULL);

  if ((result = data->buffer)) {
    data->buffer = NULL;
    data->pos = 0;
    /* one less pad with queued data now */
    pads->queuedpads--;
  }

  GST_COLLECT_PADS_BROADCAST (pads);

  GST_DEBUG ("Pop buffer on pad %s:%s: buffer=%p",
      GST_DEBUG_PAD_NAME (data->pad), result);

  return result;
}

/* pop and unref the currently queued buffer, should e called with the LOCK
 * helt. */
static void
gst_collect_pads_clear (GstCollectPads * pads, GstCollectData * data)
{
  GstBuffer *buf;

  if ((buf = gst_collect_pads_pop (pads, data)))
    gst_buffer_unref (buf);
}

/**
 * gst_collect_pads_available:
 * @pads: the collectspads to query
 *
 * Query how much bytes can be read from each queued buffer. This means
 * that the result of this call is the maximum number of bytes that can
 * be read from each of the pads.
 *
 * This function should be called with @pads LOCK held, such as
 * in the callback.
 *
 * Returns: The maximum number of bytes queued on all pads. This function
 * returns 0 if a pad has no queued buffer.
 *
 * MT safe.
 */
/* FIXME, we can do this in the _chain functions */
guint
gst_collect_pads_available (GstCollectPads * pads)
{
  GSList *collected;
  guint result = G_MAXUINT;

  g_return_val_if_fail (pads != NULL, 0);
  g_return_val_if_fail (GST_IS_COLLECT_PADS (pads), 0);

  for (collected = pads->data; collected; collected = g_slist_next (collected)) {
    GstCollectData *pdata;
    GstBuffer *buffer;
    gint size;

    pdata = (GstCollectData *) collected->data;

    /* ignore pad with EOS */
    if (G_UNLIKELY (pdata->abidata.ABI.eos)) {
      GST_DEBUG ("pad %p is EOS", pdata);
      continue;
    }

    /* an empty buffer without EOS is weird when we get here.. */
    if (G_UNLIKELY ((buffer = pdata->buffer) == NULL)) {
      GST_WARNING ("pad %p has no buffer", pdata);
      goto not_filled;
    }

    /* this is the size left of the buffer */
    size = GST_BUFFER_SIZE (buffer) - pdata->pos;
    GST_DEBUG ("pad %p has %d bytes left", pdata, size);

    /* need to return the min of all available data */
    if (size < result)
      result = size;
  }
  /* nothing changed, all must be EOS then, return 0 */
  if (G_UNLIKELY (result == G_MAXUINT))
    result = 0;

  return result;

not_filled:
  {
    return 0;
  }
}

/**
 * gst_collect_pads_read:
 * @pads: the collectspads to query
 * @data: the data to use
 * @bytes: a pointer to a byte array
 * @size: the number of bytes to read
 *
 * Get a pointer in @bytes where @size bytes can be read from the
 * given pad data.
 *
 * This function should be called with @pads LOCK held, such as
 * in the callback.
 *
 * Returns: The number of bytes available for consumption in the
 * memory pointed to by @bytes. This can be less than @size and
 * is 0 if the pad is end-of-stream.
 *
 * MT safe.
 */
guint
gst_collect_pads_read (GstCollectPads * pads, GstCollectData * data,
    guint8 ** bytes, guint size)
{
  guint readsize;
  GstBuffer *buffer;

  g_return_val_if_fail (pads != NULL, 0);
  g_return_val_if_fail (GST_IS_COLLECT_PADS (pads), 0);
  g_return_val_if_fail (data != NULL, 0);
  g_return_val_if_fail (bytes != NULL, 0);

  /* no buffer, must be EOS */
  if ((buffer = data->buffer) == NULL)
    return 0;

  readsize = MIN (size, GST_BUFFER_SIZE (buffer) - data->pos);

  *bytes = GST_BUFFER_DATA (buffer) + data->pos;

  return readsize;
}

/**
 * gst_collect_pads_flush:
 * @pads: the collectspads to query
 * @data: the data to use
 * @size: the number of bytes to flush
 *