serialization/test/test_singleton_inherited.cpp
2018-11-17 13:21:31 -08:00

82 lines
3.4 KiB
C++

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// test_singleton_inherited.cpp:
// Test the singleton class for a "inherited" singleton (used as Foo:public singleton<Foo>)
// This can be uses as singleton<Foo>::get_const_instance() OR Foo::get_const_instance()
//
// - is_destroyed returns false when singleton is active or uninitialized
// - is_destroyed returns true when singleton is destructed
// - the singleton is eventually destructed (no memory leak)
// (C) Copyright 2018 Alexander Grund
// Use, modification and distribution is subject to the Boost Software
// License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt)
#include "test_tools.hpp"
#include <boost/serialization/singleton.hpp>
#include <boost/preprocessor/stringize.hpp>
#include <stdexcept>
// Can't use BOOST_TEST because:
// a) destructors are called after program exit
// b) This is intended to be used by shared libraries too which would then need their own report_errors call
// We halso have to disable the Wterminate warning as we call this from dtors
// C++ will terminate the program in such cases which is OK here
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wterminate"
#define THROW_ON_FALSE(cond) if(!(cond)) throw std::runtime_error(__FILE__ "(" BOOST_PP_STRINGIZE(__LINE__) ") Assertion failed: " #cond)
// Enum to designate the state of the singletonized instances
enum ConstructionState{CS_UNINIT, CS_INIT, CS_DESTROYED};
// We need another singleton to check for the destruction of the singletons at program exit
// We don't need all the magic for shared library anti-optimization and can keep it very simple
struct controller{
static controller& getInstance(){
static controller instance;
return instance;
}
ConstructionState state;
private:
controller() {
state = CS_UNINIT;
}
~controller();
};
// A simple class that sets its construction state in the controller singleton
struct Foo: boost::serialization::singleton<Foo>{
Foo(): i(42) {
// access controller singleton. Therefore controller will be constructed before this
THROW_ON_FALSE(controller::getInstance().state == CS_UNINIT);
controller::getInstance().state = CS_INIT;
}
~Foo() {
// Because controller is constructed before this, it will be destructed AFTER this. Hence controller is still valid
THROW_ON_FALSE(controller::getInstance().state == CS_INIT);
controller::getInstance().state = CS_DESTROYED;
}
// Volatile to prevent compiler optimization from removing this
volatile int i;
};
controller::~controller() {
// If this fails, the singletons were not freed and memory is leaked
THROW_ON_FALSE(state == CS_DESTROYED);
// If this fails, then the destroyed flag is not set and one may use a deleted instance if relying on this flag
THROW_ON_FALSE(boost::serialization::singleton<Foo>::is_destroyed());
THROW_ON_FALSE(Foo::is_destroyed());
}
int
test_main( int /* argc */, char* /* argv */[] )
{
// Check if the singleton is alive and use it
BOOST_CHECK(!boost::serialization::singleton<Foo>::is_destroyed());
BOOST_CHECK(!Foo::is_destroyed());
BOOST_CHECK(boost::serialization::singleton<Foo>::get_const_instance().i == 42);
BOOST_CHECK(Foo::get_const_instance().i == 42);
return EXIT_SUCCESS;
}