[libcamera-devel] [PATCH 1/2] test: gstreamer: Simplify elements' ownerships

[Umang Jain]

In gstreamer, when elements are created, usually a floating [1]
reference is returned which simply means, there is no ownership
transfer (yet). Once can simply check for NULL and return through
an error path, without bothering to clean up. Hence, g_autoptr is
not much of help here.

If the NULL checks have been passed successfully, elements are ready
to use. However, we must claim ownership/reference it before using
them via g_object_ref_sink().

This patch build upon this principle and removes the g_autoptr
from gstreamer tests whereever necessary to tide up the code.

[1] https://gstreamer.freedesktop.org/documentation/additional/design/MT-refcounting.html?gi-language=c#refcounting1

Signed-off-by: Umang Jain <umang.jain at ideasonboard.com>
---
 test/gstreamer/gstreamer_single_stream_test.cpp | 14 ++++++--------
 test/gstreamer/gstreamer_test.cpp               |  9 ++++-----
 2 files changed, 10 insertions(+), 13 deletions(-)

diff --git a/test/gstreamer/gstreamer_single_stream_test.cpp b/test/gstreamer/gstreamer_single_stream_test.cpp
index 7292f328..d992455c 100644
--- a/test/gstreamer/gstreamer_single_stream_test.cpp
+++ b/test/gstreamer/gstreamer_single_stream_test.cpp
@@ -33,20 +33,18 @@ protected:
 		if (status_ != TestPass)
 			return status_;
 
-		g_autoptr(GstElement) convert0 = gst_element_factory_make("videoconvert", "convert0");
-		g_autoptr(GstElement) sink0 = gst_element_factory_make("fakesink", "sink0");
-		g_object_ref_sink(convert0);
-		g_object_ref_sink(sink0);
+		convert0_ = gst_element_factory_make("videoconvert", "convert0");
+		sink0_ = gst_element_factory_make("fakesink", "sink0");
 
-		if (!convert0 || !sink0) {
+		if (!convert0_ || !sink0_) {
 			g_printerr("Not all elements could be created. %p.%p\n",
-				   convert0, sink0);
+				   convert0_, sink0_);
 
 			return TestFail;
 		}
 
-		convert0_ = reinterpret_cast<GstElement *>(g_steal_pointer(&convert0));
-		sink0_ = reinterpret_cast<GstElement *>(g_steal_pointer(&sink0));
+		g_object_ref_sink(convert0_);
+		g_object_ref_sink(sink0_);
 
 		if (createPipeline() != TestPass)
 			return TestFail;
diff --git a/test/gstreamer/gstreamer_test.cpp b/test/gstreamer/gstreamer_test.cpp
index 41712505..227a5c37 100644
--- a/test/gstreamer/gstreamer_test.cpp
+++ b/test/gstreamer/gstreamer_test.cpp
@@ -78,18 +78,17 @@ GstreamerTest::~GstreamerTest()
 
 int GstreamerTest::createPipeline()
 {
-	g_autoptr(GstElement) libcameraSrc = gst_element_factory_make("libcamerasrc", "libcamera");
+	libcameraSrc_ = gst_element_factory_make("libcamerasrc", "libcamera");
 	pipeline_ = gst_pipeline_new("test-pipeline");
-	g_object_ref_sink(libcameraSrc);
 
-	if (!libcameraSrc || !pipeline_) {
+	if (!libcameraSrc_ || !pipeline_) {
 		g_printerr("Unable to create create pipeline %p.%p\n",
-			   libcameraSrc, pipeline_);
+			   libcameraSrc_, pipeline_);
 
 		return TestFail;
 	}
 
-	libcameraSrc_ = reinterpret_cast<GstElement *>(g_steal_pointer(&libcameraSrc));
+	g_object_ref_sink(libcameraSrc_);
 
 	return TestPass;
 }
-- 
2.31.1