有没有办法知道正在运行的进程的C++对象数量及其类型？

Question

仅在 Windows 上运行的进程之一的内存占用比以前使用更多的内存，我想知道内存中存在哪些所有 C++ 对象，以查看是否有额外的分配？ 我可以使用 WinDbg for .NET 应用程序来找到它。但是，是否可以在不购买内存分析器商业应用程序的情况下为 C++ 做到这一点？

Answer 1

如果您买不起工具，您也许可以使用 mixin 代码向每个类添加实例计数，如下所示（当然您可能希望输出到日志文件）。我现在时间不多了，所以如果您有疑问，请询问他们，我稍后再回复。

#include <utility>
#include <iostream>
#include <atomic>
#include <string_view>

class report_instance_count_itf
{
public:
    virtual void report_construction(std::string_view type_name, std::size_t number_of_instances) const noexcept = 0;
    virtual void report_destruction(std::string_view type_name, std::size_t number_of_instances) const noexcept = 0;
};

class cout_reporter_t : public report_instance_count_itf
{
public:
    void report_construction(std::string_view type_name, std::size_t number_of_instances) const noexcept override
    {
        std::cout << "construct of class `" << type_name << "` number of instances = " << number_of_instances << "\n";
    }

    void report_destruction(std::string_view type_name, std::size_t number_of_instances) const noexcept override
    {
        std::cout << "destruction of class `" << type_name << "` number of instances = " << number_of_instances << "\n";
    }
};

//------------------------------------------------------------------------------
// meyers singleton for now (ideally inject)
const report_instance_count_itf& get_instance_count_reporter()
{
    static cout_reporter_t reporter;
    return reporter;
}

//------------------------------------------------------------------------------
// Reusable instance counter implementation,
// make it a class template so we get a unique "instance" per
// class type that uses it. 
// put this class template in its own header file

template<typename class_t>
class instance_counter_impl_t
{
public:
    instance_counter_impl_t()
    {
        ++m_instance_count;
        const std::type_info& ti = typeid(class_t);
        get_instance_count_reporter().report_construction(ti.name(), m_instance_count);
    }

    ~instance_counter_impl_t()
    {
        --m_instance_count;
        const std::type_info& ti = typeid(class_t);
        get_instance_count_reporter().report_destruction(ti.name(), m_instance_count);
    }

    const auto instance_count() const noexcept
    {
        return m_instance_count;
    }

private:
    static std::atomic<std::size_t> m_instance_count;
};

template<typename class_t>
std::atomic<std::size_t> instance_counter_impl_t<class_t>::m_instance_count{};

// End of header file 
//------------------------------------------------------------------------------

// inherit each class you want to count the number of instaces of
// from the class template specialized for that class. 
enter code here
class A :
    public instance_counter_impl_t<A>
{
};

class B :
    public instance_counter_impl_t<B>
{
};

int main()
{
    {
        A a1;
        B b1;
        A a2;
        B b2;
    }

    return 0;
}