GTest functional tests that include parameters and uORB messaging (#12521)

* Add kdevelop to gitignore

* Add test stubs

* Rename px4_add_gtest to px4_add_unit_gtest

* Add infrastructure to run functional tests

* Add example tests with parameters and uorb messages

* Fix memory issues in destructors in uORB manager and CDev

* Add a more real-world test of the collision prevention

src/platforms/CMakeLists.txt

@@ -32,3 +32,7 @@
 ############################################################################
 
 add_subdirectory(common)
+
+if (${PX4_PLATFORM} STREQUAL "posix" AND BUILD_TESTING)
+	add_subdirectory(posix/test_stubs)
+endif()

src/platforms/apps.h.in

@@ -4,6 +4,7 @@
 
 #include "px4_tasks.h"	// px4_main_t
 #include <map>
+#include <string>
 
 // Maps an app name to it's function.
 typedef std::map<std::string, px4_main_t> apps_map_type;

src/platforms/posix/test_stubs/CMakeLists.txt

@@ -0,0 +1,41 @@
+############################################################################
+#
+#   Copyright (c) 2019 PX4 Development Team. All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions
+# are met:
+#
+# 1. Redistributions of source code must retain the above copyright
+#    notice, this list of conditions and the following disclaimer.
+# 2. Redistributions in binary form must reproduce the above copyright
+#    notice, this list of conditions and the following disclaimer in
+#    the documentation and/or other materials provided with the
+#    distribution.
+# 3. Neither the name PX4 nor the names of its contributors may be
+#    used to endorse or promote products derived from this software
+#    without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+# FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+# COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+# INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+# BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+# OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+# AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+# ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+# POSSIBILITY OF SUCH DAMAGE.
+#
+############################################################################
+
+set(SRCS
+    stub_daemon.cpp
+    stub_devmgr.cpp
+    stub_parameter.cpp
+   )
+
+px4_add_library(test_stubs ${SRCS})
+message("-- ADDING TEST STUBS")

src/platforms/posix/test_stubs/stub_daemon.cpp

@@ -0,0 +1,6 @@
+#include "stub_daemon.h"
+
+
+void init_app_map(apps_map_type &apps) {stub_init_app_map_callback(apps);}
+
+void list_builtins(apps_map_type &apps) {stub_list_builtins_callback(apps);}

src/platforms/posix/test_stubs/stub_daemon.h

@@ -0,0 +1,8 @@
+#pragma once
+
+#include <platforms/posix/apps.h>
+
+#include <functional>
+
+std::function<void(apps_map_type &apps)> stub_init_app_map_callback = [](apps_map_type &) {};
+std::function<void(apps_map_type &apps)> stub_list_builtins_callback = [](apps_map_type &) {};

src/platforms/posix/test_stubs/stub_devmgr.cpp

@@ -0,0 +1,10 @@
+#include "stub_devmgr.h"
+
+
+namespace DriverFramework
+{
+int DevMgr::getNextDeviceName(unsigned int &index, const char **instancename)
+{
+	return stub_getNextDeviceName_callback(index, instancename);
+}
+}

src/platforms/posix/test_stubs/stub_devmgr.h

@@ -0,0 +1,8 @@
+#pragma once
+
+#include "DevMgr.hpp"
+
+#include <functional>
+
+std::function<int(unsigned int &, const char **)> stub_getNextDeviceName_callback = [](unsigned int &,
+const char **) {return 0;};

src/platforms/posix/test_stubs/stub_parameter.cpp

@@ -0,0 +1,11 @@
+#include "stub_parameter.h"
+
+
+
+extern "C" {
+	/* This function blocks forever in tests, so override it with a version that can be customized */
+	int pthread_cond_wait(pthread_cond_t *cond, pthread_mutex_t *mutex)
+	{
+		return stub_pthread_cond_wait_callback(cond, mutex);
+	}
+}

src/platforms/posix/test_stubs/stub_parameter.h

@@ -0,0 +1,8 @@
+#pragma once
+
+#include <pthread.h>
+
+#include <functional>
+
+std::function<int(pthread_cond_t *, pthread_mutex_t *)> stub_pthread_cond_wait_callback =
+[](pthread_cond_t *, pthread_mutex_t *) {return 0;};