[Cogl] [PATCH] cogl-gst: adds _sink_is_ready() api

[Robert Bragg]

From: Robert Bragg <robert at linux.intel.com>

Thinking about this a bit more, I realized that this makes the _get_pipeline()
api inconsistent with the _setup_pipeline() api which can be used for
completely custom pipelines and in the case of _setup_pipeline() we aren't able
to just return NULL to indicate that the pipeline wasn't ready.

Alternatively I wondered whether a cogl_gst_video_sink_is_ready() function
would work for instead so you can directly check the status before calling
cogl_gst_video_sink_get_pipeline() in any case where you haven't been able to
connect a signal handler for the pipeline-ready signal?

If this could work then maybe we can use the patch below?

kind regards,
- Robert

--- >8 ---

This adds a cogl_gst_video_sink_is_ready() for code to be able to check
if its safe to call cogl_gst_video_sink_get_pipeline() or
cogl_gst_video_sink_setup_pipeline() without causing an error. Normally
application listen for the pipeline-ready signal but sometimes a sink
can be passed between components that didn't have an opportunity to
connect a signal handler, so they need a way to directly check the
status.
---
 cogl-gst/cogl-gst-video-sink.c |  6 ++++++
 cogl-gst/cogl-gst-video-sink.h | 20 ++++++++++++++++++++
 2 files changed, 26 insertions(+)

diff --git a/cogl-gst/cogl-gst-video-sink.c b/cogl-gst/cogl-gst-video-sink.c
index 2cd63ae..3018de1 100644
--- a/cogl-gst/cogl-gst-video-sink.c
+++ b/cogl-gst/cogl-gst-video-sink.c
@@ -1355,3 +1355,9 @@ cogl_gst_video_sink_fit_size (CoglGstVideoSink *vt,
         }
     }
 }
+
+CoglBool
+cogl_gst_video_sink_is_ready (CoglGstVideoSink *sink)
+{
+  return !!sink->renderer;
+}
diff --git a/cogl-gst/cogl-gst-video-sink.h b/cogl-gst/cogl-gst-video-sink.h
index 45ed835..6c59e7c 100644
--- a/cogl-gst/cogl-gst-video-sink.h
+++ b/cogl-gst/cogl-gst-video-sink.h
@@ -192,6 +192,26 @@ CoglGstVideoSink *
 cogl_gst_video_sink_new (CoglContext *ctx);
 
 /**
+ * cogl_gst_video_sink_is_ready:
+ * @sink: The #CoglGstVideoSink
+ *
+ * Returns whether the pipeline is ready and so
+ * cogl_gst_video_sink_get_pipeline() and
+ * cogl_gst_video_sink_setup_pipeline() can be called without causing error.
+ *
+ * Note: Normally an application will wait until the
+ * #CoglGstVideoSink::pipeline-ready signal is emitted instead of
+ * polling the ready status with this api, but sometimes when a sink
+ * is passed between components that didn't have an opportunity to
+ * connect a signal handler this can be useful.
+ *
+ * Return value: %TRUE if the sink is ready, else %FALSE
+ * Since: 1.16
+ */
+CoglBool
+cogl_gst_video_sink_is_ready (CoglGstVideoSink *sink);
+
+/**
  * cogl_gst_video_sink_get_pipeline:
  * @vt: The #CoglGstVideoSink
  *
-- 
1.8.3.1