[libcamera-devel] [PATCH] test: CameraManager: Add start/stop tests

[Kieran Bingham]

Validate the CameraManager can start, stop, and restart successfully, as
well as highlight that we can not construct a second CameraManager
without hitting assertions.

Signed-off-by: Kieran Bingham <kieran.bingham at ideasonboard.com>
---
This introduces some basic tests on the lifetime of the CameraManager.

Integration is optional, but I'm posting to higlight the investigations
I did on this yesterday.

 - We can successfully construct, use and destroy a CameraManager
   and then reconstruct a new one and use that too.

 - Construction of a CameraManager, with a start()/stop() cycle will
   not function using the same CameraManager if we try to re-start()
   the same instance.

 - Construction of two CameraManager instances causes a FATAL assertion
   though somewhat confusingly, it will face a FATAL assertion on the
   second IPAManager construction, before the second CameraManager gets
   to execute its constructor.


 test/camera-manager.cpp | 106 ++++++++++++++++++++++++++++++++++++++++
 test/meson.build        |   1 +
 2 files changed, 107 insertions(+)
 create mode 100644 test/camera-manager.cpp

diff --git a/test/camera-manager.cpp b/test/camera-manager.cpp
new file mode 100644
index 000000000000..9e9c494af21c
--- /dev/null
+++ b/test/camera-manager.cpp
@@ -0,0 +1,106 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Copyright (C) 2021, Google Inc.
+ *
+ * libcamera Camera Manager API tests
+ */
+
+#include <iostream>
+#include <memory>
+
+#include <libcamera/camera.h>
+#include <libcamera/camera_manager.h>
+
+#include "test.h"
+
+using namespace libcamera;
+using namespace std;
+
+class CameraManagerTest : public Test
+{
+protected:
+	int validate()
+	{
+		std::shared_ptr<Camera> camera;
+
+		if (cm_->start()) {
+			cerr << "Failed to start camera manager" << endl;
+			return TestFail;
+		}
+
+		if (cm_->cameras().size() <= 0) {
+			cerr << "No cameras available" << endl;
+			return TestFail;
+		}
+
+		camera = cm_->cameras()[0];
+		if (!camera) {
+			cerr << "Can not obtain a camera at index 0" << endl;
+			return TestFail;
+		}
+
+		/* Store the camera id that we get */
+		cameraId_ = camera->id();
+
+		return TestPass;
+	}
+
+	int run()
+	{
+		std::string firstCamera;
+
+		/* Construct and validate the CameraManager */
+		cm_ = new CameraManager();
+		if (validate()) {
+			cerr << "Failed first construction" << endl;
+			return TestFail;
+		}
+
+		/* Get camera ID stored by validate */
+		firstCamera = cameraId_;
+
+		/* Now stop everything and reconstruct the CameraManager */
+		cm_->stop();
+		delete cm_;
+
+		/* Restart and assert we can still get a camera */
+		cm_ = new CameraManager();
+		if (validate()) {
+			cerr << "Failed after re-construction" << endl;
+			return TestFail;
+		}
+
+		if (firstCamera != cameraId_) {
+			cerr << "Expected to get the same camera after re-construction" << endl;
+			return TestFail;
+		}
+
+		/* Test stop and start (without re-create) */
+		cm_->stop();
+
+		/* validate will call start() */
+		if (validate()) {
+			cerr << "Failed after re-starting CameraManager" << endl;
+			return TestFail;
+		}
+
+		/*
+		 * Creating a second camera manager is not permitted
+		 *
+		 * This will fail with a FATAL in constructing a second IPA
+		 * Manager, even though we also have a FATAL in the
+		 * CameraManager construction, but the CameraManager tries
+		 * to construct an IPA manager, which fails before the
+		 * CameraManager executes any of it's constructor.
+		 */
+		//CameraManager *cm2 = new CameraManager();
+
+		return TestPass;
+	}
+
+private:
+	CameraManager *cm_;
+	std::string cameraId_;
+};
+
+TEST_REGISTER(CameraManagerTest)
diff --git a/test/meson.build b/test/meson.build
index 2c3e76546fbc..cd23c07e1f16 100644
--- a/test/meson.build
+++ b/test/meson.build
@@ -24,6 +24,7 @@ subdir('v4l2_subdevice')
 subdir('v4l2_videodevice')
 
 public_tests = [
+    ['camera-manager',                  'camera-manager.cpp'],
     ['geometry',                        'geometry.cpp'],
     ['public-api',                      'public-api.cpp'],
     ['signal',                          'signal.cpp'],
-- 
2.30.2