C++ GST_STATE函数代码示例

static void
gst_win_inet_src_set_property (GObject * object, guint prop_id,
    const GValue * value, GParamSpec * pspec)
{
  GstWinInetSrc *self = GST_WIN_INET_SRC (object);

  switch (prop_id) {
    case PROP_LOCATION:
      if (GST_STATE (self) == GST_STATE_PLAYING ||
          GST_STATE (self) == GST_STATE_PAUSED) {
        GST_WARNING_OBJECT (self, "element must be in stopped or paused state "
            "in order to change location");
        break;
      }

      g_free (self->location);
      self->location = g_value_dup_string (value);
      break;

    case PROP_POLL_MODE:
      self->poll_mode = g_value_get_boolean (value);
      break;

    case PROP_IRADIO_MODE:
      self->iradio_mode = g_value_get_boolean (value);
      break;

    default:
      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
      break;
  }
}

static void
gst_audio_echo_set_property (GObject * object, guint prop_id,
    const GValue * value, GParamSpec * pspec)
{
  GstAudioEcho *self = GST_AUDIO_ECHO (object);

  switch (prop_id) {
    case PROP_DELAY:{
      guint64 max_delay, delay;

      GST_BASE_TRANSFORM_LOCK (self);
      delay = g_value_get_uint64 (value);
      max_delay = self->max_delay;

      if (delay > max_delay && GST_STATE (self) > GST_STATE_READY) {
        GST_WARNING_OBJECT (self, "New delay (%" GST_TIME_FORMAT ") "
            "is larger than maximum delay (%" GST_TIME_FORMAT ")",
            GST_TIME_ARGS (delay), GST_TIME_ARGS (max_delay));
        self->delay = max_delay;
      } else {
        self->delay = delay;
        self->max_delay = MAX (delay, max_delay);
      }
      GST_BASE_TRANSFORM_UNLOCK (self);
    }
      break;
    case PROP_MAX_DELAY:{
      guint64 max_delay, delay;

      GST_BASE_TRANSFORM_LOCK (self);
      max_delay = g_value_get_uint64 (value);
      delay = self->delay;

      if (GST_STATE (self) > GST_STATE_READY) {
        GST_ERROR_OBJECT (self, "Can't change maximum delay in"
            " PLAYING or PAUSED state");
      } else {
        self->delay = delay;
        self->max_delay = max_delay;
      }
      GST_BASE_TRANSFORM_UNLOCK (self);
    }
      break;
    case PROP_INTENSITY:{
      GST_BASE_TRANSFORM_LOCK (self);
      self->intensity = g_value_get_float (value);
      GST_BASE_TRANSFORM_UNLOCK (self);
    }
      break;
    case PROP_FEEDBACK:{
      GST_BASE_TRANSFORM_LOCK (self);
      self->feedback = g_value_get_float (value);
      GST_BASE_TRANSFORM_UNLOCK (self);
    }
      break;
    default:
      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
      break;
  }
}

G_MODULE_EXPORT gboolean
preview_draw_cb(
    GtkWidget *widget,
    cairo_t *cr,
    signal_user_data_t *ud)
{
#if defined(_ENABLE_GST)
#if GST_CHECK_VERSION(1, 0, 0)
    if (ud->preview->live_enabled && ud->preview->state == PREVIEW_STATE_LIVE)
    {
        if (GST_STATE(ud->preview->play) >= GST_STATE_PAUSED)
        {
            GstElement *vsink;
            GstVideoOverlay *vover;

            g_object_get(ud->preview->play, "video-sink", &vsink, NULL);
            if (GST_IS_BIN(vsink))
                vover = GST_VIDEO_OVERLAY(gst_bin_get_by_interface(
                                    GST_BIN(vsink), GST_TYPE_VIDEO_OVERLAY));
            else
                vover = GST_VIDEO_OVERLAY(vsink);
            gst_video_overlay_expose(vover);
            // For some reason, the exposed region doesn't always get
            // cleaned up here. But a delayed gst_x_overlay_expose()
            // takes care of it.
            g_idle_add((GSourceFunc)delayed_expose_cb, ud);
        }
        return FALSE;
    }
#else
    if (ud->preview->live_enabled && ud->preview->state == PREVIEW_STATE_LIVE)
    {
        if (GST_STATE(ud->preview->play) >= GST_STATE_PAUSED)
        {
            GstElement *vsink;
            GstXOverlay *xover;

            g_object_get(ud->preview->play, "video-sink", &vsink, NULL);
            if (GST_IS_BIN(vsink))
                xover = GST_X_OVERLAY(gst_bin_get_by_interface(
                                        GST_BIN(vsink), GST_TYPE_X_OVERLAY));
            else
                xover = GST_X_OVERLAY(vsink);
            gst_x_overlay_expose(xover);
            // For some reason, the exposed region doesn't always get
            // cleaned up here. But a delayed gst_x_overlay_expose()
            // takes care of it.
            g_idle_add((GSourceFunc)delayed_expose_cb, ud);
        }
        return FALSE;
    }
#endif
#endif

    if (ud->preview->pix != NULL)
    {
        _draw_pixbuf(cr, ud->preview->pix);
    }
    return FALSE;
}

void
gst_gio_base_src_set_stream (GstGioBaseSrc * src, GInputStream * stream)
{
  gboolean success;

  GError *err = NULL;

  g_return_if_fail (G_IS_INPUT_STREAM (stream));
  g_return_if_fail ((GST_STATE (src) != GST_STATE_PLAYING &&
          GST_STATE (src) != GST_STATE_PAUSED));

  if (G_IS_INPUT_STREAM (src->stream)) {
    GST_DEBUG_OBJECT (src, "closing old stream");

    /* FIXME: can block but unfortunately we can't use async operations
     * here because they require a running main loop */
    success = g_input_stream_close (src->stream, src->cancel, &err);

    if (!success && !gst_gio_error (src, "g_input_stream_close", &err, NULL)) {
      GST_ELEMENT_WARNING (src, RESOURCE, CLOSE, (NULL),
          ("g_input_stream_close failed: %s", err->message));
      g_clear_error (&err);
    } else if (!success) {
      GST_ELEMENT_WARNING (src, RESOURCE, CLOSE, (NULL),
          ("g_input_stream_close failed"));
    } else {
      GST_DEBUG_OBJECT (src, "g_input_stream_close succeeded");
    }

    g_object_unref (src->stream);
    src->stream = NULL;
  }

  src->stream = stream;
}

static void
gst_jack_audio_src_set_property (GObject * object, guint prop_id,
    const GValue * value, GParamSpec * pspec)
{
  GstJackAudioSrc *src = GST_JACK_AUDIO_SRC (object);

  switch (prop_id) {
    case PROP_CLIENT_NAME:
      g_free (src->client_name);
      src->client_name = g_value_dup_string (value);
      break;
    case PROP_CONNECT:
      src->connect = g_value_get_enum (value);
      break;
    case PROP_SERVER:
      g_free (src->server);
      src->server = g_value_dup_string (value);
      break;
    case PROP_CLIENT:
      if (GST_STATE (src) == GST_STATE_NULL ||
          GST_STATE (src) == GST_STATE_READY) {
        src->jclient = g_value_get_boxed (value);
      }
      break;
    case PROP_TRANSPORT:
      src->transport = g_value_get_flags (value);
      break;
    default:
      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
      break;
  }
}

static void
gst_gio_stream_sink_set_property (GObject * object, guint prop_id,
    const GValue * value, GParamSpec * pspec)
{
  GstGioStreamSink *sink = GST_GIO_STREAM_SINK (object);

  switch (prop_id) {
    case PROP_STREAM:{
      GObject *stream;

      if (GST_STATE (sink) == GST_STATE_PLAYING ||
          GST_STATE (sink) == GST_STATE_PAUSED) {
        GST_WARNING
            ("Setting a new stream not supported in PLAYING or PAUSED state");
        break;
      }

      stream = g_value_dup_object (value);
      if (sink->stream)
        g_object_unref (sink->stream);
      sink->stream = G_OUTPUT_STREAM (stream);
      break;
    }
    default:
      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
      break;
  }
}

static gboolean gst_imx_v4l2src_set_focus_mode(GstPhotography *photo,
		GstPhotographyFocusMode focus_mode)
{
	GstImxV4l2VideoSrc *v4l2src = GST_IMX_V4L2SRC(photo);

	GST_LOG_OBJECT(v4l2src, "setting focus mode to %d", focus_mode);

	switch (focus_mode) {
	case GST_PHOTOGRAPHY_FOCUS_MODE_AUTO:
	case GST_PHOTOGRAPHY_FOCUS_MODE_MACRO:
	case GST_PHOTOGRAPHY_FOCUS_MODE_PORTRAIT:
	case GST_PHOTOGRAPHY_FOCUS_MODE_INFINITY:
		break;
	case GST_PHOTOGRAPHY_FOCUS_MODE_CONTINUOUS_NORMAL:
	case GST_PHOTOGRAPHY_FOCUS_MODE_CONTINUOUS_EXTENDED:
		focus_mode = GST_PHOTOGRAPHY_FOCUS_MODE_CONTINUOUS_NORMAL;
		break;
	default:
		GST_WARNING_OBJECT(v4l2src, "focus mode %d is not supported", focus_mode);
		return FALSE;
	}

	g_mutex_lock(&v4l2src->af_mutex);

	if (v4l2src->focus_mode != focus_mode) {
		v4l2src->focus_mode = focus_mode;

		if (GST_STATE(v4l2src) == GST_STATE_PAUSED || GST_STATE(v4l2src) == GST_STATE_PLAYING)
			gst_imx_v4l2src_apply_focus_settings(v4l2src, TRUE);
	}

	g_mutex_unlock(&v4l2src->af_mutex);

	return TRUE;
}

static gboolean
do_toggle_element (GstGConfVideoSrc * src)
{
  GstPad *targetpad;
  gchar *new_gconf_str;
  GstState cur, next;

  new_gconf_str = gst_gconf_get_string (GST_GCONF_AUDIOSRC_KEY);
  if (new_gconf_str != NULL && src->gconf_str != NULL &&
      (strlen (new_gconf_str) == 0 ||
          strcmp (src->gconf_str, new_gconf_str) == 0)) {
    g_free (new_gconf_str);
    GST_DEBUG_OBJECT (src, "GConf key was updated, but it didn't change");
    return TRUE;
  }

  GST_OBJECT_LOCK (src);
  cur = GST_STATE (src);
  next = GST_STATE_PENDING (src);
  GST_OBJECT_UNLOCK (src);

  if (cur >= GST_STATE_READY || next == GST_STATE_PAUSED) {
    GST_DEBUG_OBJECT (src, "already running, ignoring GConf change");
    g_free (new_gconf_str);
    return TRUE;
  }

  g_free (src->gconf_str);
  src->gconf_str = new_gconf_str;

  /* kill old element */
  if (src->kid) {
    GST_DEBUG_OBJECT (src, "Removing old kid");
    gst_element_set_state (src->kid, GST_STATE_NULL);
    gst_bin_remove (GST_BIN (src), src->kid);
    src->kid = NULL;
  }

  GST_DEBUG_OBJECT (src, "Creating new kid");
  if (!(src->kid = gst_gconf_get_default_video_src ())) {
    GST_ELEMENT_ERROR (src, LIBRARY, SETTINGS, (NULL),
        ("Failed to render video source from GConf"));
    g_free (src->gconf_str);
    src->gconf_str = NULL;
    return FALSE;
  }
  gst_element_set_state (src->kid, GST_STATE (src));
  gst_bin_add (GST_BIN (src), src->kid);

  /* re-attach ghostpad */
  GST_DEBUG_OBJECT (src, "Creating new ghostpad");
  targetpad = gst_element_get_static_pad (src->kid, "src");
  gst_ghost_pad_set_target (GST_GHOST_PAD (src->pad), targetpad);
  gst_object_unref (targetpad);
  GST_DEBUG_OBJECT (src, "done changing gconf video source");

  return TRUE;
}

static void
gst_gio_src_set_property (GObject * object, guint prop_id,
    const GValue * value, GParamSpec * pspec)
{
  GstGioSrc *src = GST_GIO_SRC (object);

  switch (prop_id) {
    case PROP_LOCATION:{
      const gchar *uri = NULL;

      if (GST_STATE (src) == GST_STATE_PLAYING ||
          GST_STATE (src) == GST_STATE_PAUSED) {
        GST_WARNING
            ("Setting a new location or GFile not supported in PLAYING or PAUSED state");
        break;
      }

      GST_OBJECT_LOCK (GST_OBJECT (src));
      if (src->file)
        g_object_unref (src->file);

      uri = g_value_get_string (value);

      if (uri) {
        src->file = g_file_new_for_uri (uri);

        if (!src->file) {
          GST_ERROR ("Could not create GFile for URI '%s'", uri);
        }
      } else {
        src->file = NULL;
      }
      GST_OBJECT_UNLOCK (GST_OBJECT (src));
      break;
    }
    case PROP_FILE:
      if (GST_STATE (src) == GST_STATE_PLAYING ||
          GST_STATE (src) == GST_STATE_PAUSED) {
        GST_WARNING
            ("Setting a new location or GFile not supported in PLAYING or PAUSED state");
        break;
      }

      GST_OBJECT_LOCK (GST_OBJECT (src));
      if (src->file)
        g_object_unref (src->file);

      src->file = g_value_dup_object (value);

      GST_OBJECT_UNLOCK (GST_OBJECT (src));
      break;
    default:
      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
      break;
  }
}

static void
gst_gnome_vfs_src_set_property (GObject * object, guint prop_id,
    const GValue * value, GParamSpec * pspec)
{
  GstGnomeVFSSrc *src;

  src = GST_GNOME_VFS_SRC (object);

  switch (prop_id) {
    case ARG_LOCATION:{
      const gchar *new_location;

      /* the element must be stopped or paused in order to do this */
      if (GST_STATE (src) == GST_STATE_PLAYING ||
          GST_STATE (src) == GST_STATE_PAUSED)
        break;

      if (src->uri) {
        gnome_vfs_uri_unref (src->uri);
        src->uri = NULL;
      }
      if (src->uri_name) {
        g_free (src->uri_name);
        src->uri_name = NULL;
      }

      new_location = g_value_get_string (value);
      if (new_location) {
        src->uri_name = gst_gnome_vfs_location_to_uri_string (new_location);
        src->uri = gnome_vfs_uri_new (src->uri_name);
      }
      break;
    }
    case ARG_HANDLE:
      if (GST_STATE (src) == GST_STATE_NULL ||
          GST_STATE (src) == GST_STATE_READY) {
        if (src->uri) {
          gnome_vfs_uri_unref (src->uri);
          src->uri = NULL;
        }
        if (src->uri_name) {
          g_free (src->uri_name);
          src->uri_name = NULL;
        }
        src->handle = g_value_get_boxed (value);
      }
      break;
    case ARG_IRADIO_MODE:
      src->iradio_mode = g_value_get_boolean (value);
      break;
    default:
      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
      break;
  }
}

static gboolean
gst_gnome_vfs_src_uri_set_uri (GstURIHandler * handler, const gchar * uri)
{
  GstGnomeVFSSrc *src = GST_GNOME_VFS_SRC (handler);

  if (GST_STATE (src) == GST_STATE_PLAYING ||
      GST_STATE (src) == GST_STATE_PAUSED)
    return FALSE;

  g_object_set (G_OBJECT (src), "location", uri, NULL);

  return TRUE;
}

static gboolean
rb_daap_src_uri_set_uri (GstURIHandler *handler,
			 const gchar *uri)
{
	RBDAAPSrc *src = RB_DAAP_SRC (handler);

	if (GST_STATE (src) == GST_STATE_PLAYING || GST_STATE (src) == GST_STATE_PAUSED) {
		return FALSE;
	}

	g_object_set (G_OBJECT (src), "location", uri, NULL);

	return TRUE;
}

static gboolean
gst_auto_audio_sink_detect (GstAutoAudioSink * sink)
{
  GstElement *esink;
  GstPad *targetpad;

  gst_auto_audio_sink_clear_kid (sink);

  /* find element */
  GST_DEBUG_OBJECT (sink, "Creating new kid");
  if (!(esink = gst_auto_audio_sink_find_best (sink)))
    goto no_sink;

  g_object_set (G_OBJECT (esink), "ts-offset", sink->ts_offset, NULL);

  sink->kid = esink;
  /* Ensure the child is brought up to the right state to match the parent
   * although it's currently always in READY and 
   * we're always doing NULL->READY. */
  if (GST_STATE (sink->kid) < GST_STATE (sink))
    gst_element_set_state (sink->kid, GST_STATE (sink));

  gst_bin_add (GST_BIN (sink), esink);

  /* attach ghost pad */
  GST_DEBUG_OBJECT (sink, "Re-assigning ghostpad");
  targetpad = gst_element_get_static_pad (sink->kid, "sink");
  if (!gst_ghost_pad_set_target (GST_GHOST_PAD (sink->pad), targetpad))
    goto target_failed;

  gst_object_unref (targetpad);
  GST_DEBUG_OBJECT (sink, "done changing auto audio sink");

  return TRUE;

  /* ERRORS */
no_sink:
  {
    GST_ELEMENT_ERROR (sink, LIBRARY, INIT, (NULL),
        ("Failed to find a supported audio sink"));
    return FALSE;
  }
target_failed:
  {
    GST_ELEMENT_ERROR (sink, LIBRARY, INIT, (NULL),
        ("Failed to set target pad"));
    gst_object_unref (targetpad);
    return FALSE;
  }
}

static gboolean
rbspotifysrc_uri_set_uri (GstURIHandler *handler,
			 const gchar *uri)
{
	RBSpotifySrc *src = RBSPOTIFYSRC (handler);

	if (GST_STATE (src) == GST_STATE_PLAYING || GST_STATE (src) == GST_STATE_PAUSED) {
		return FALSE;
	}

	g_object_set (G_OBJECT (src), "uri", uri, NULL);

	return TRUE;
}

static gboolean
rb_mtp_src_uri_set_uri (GstURIHandler *handler, const gchar *uri)
{
	RBMTPSrc *src = RB_MTP_SRC (handler);

	if (GST_STATE (src) == GST_STATE_PLAYING || GST_STATE (src) == GST_STATE_PAUSED) {
		return FALSE;
	}

	if (g_str_has_prefix (uri, "xrbmtp://") == FALSE) {
		return FALSE;
	}

	return rb_mtp_src_set_uri (src, uri);
}