#pragma once
#include <memory>
#include "Test.hpp"
namespace smart_pointer {
// `exception` class definition
class exception:std::exception {
using base_class = std::exception;
using base_class::base_class;
};
// `SmartPointer` class declaration
template <
typename T,
typename Allocator
>
class SmartPointer {
// don't remove this macro
ENABLE_CLASS_TESTS;
public:
using value_type = T;
explicit SmartPointer(value_type* x = nullptr) {
if (x != nullptr) {
core = new Core(x);
core->c++;
} else {
core = nullptr;
}
}
// copy constructor
SmartPointer(const SmartPointer& other) {
core = other.core;
if (core != nullptr) {
core->c++;
}
}
// move constructor
SmartPointer(SmartPointer&& other) noexcept {
core = other.core;
other.core = nullptr;
}
// copy assigment
SmartPointer &operator=(const SmartPointer& other) {
if (core != nullptr) {
if (core->c > 1) {
core->c--;
} else {
delete (core);
}
}
core = other.core;
if (core != nullptr) {
other.core->c++;
}
return *this;
}
// move assigment
SmartPointer &operator=(SmartPointer&& other) {
core = other.core;
delete other.core->p;
other.core = nullptr;
return *this;
}
//
SmartPointer &operator=(value_type* other) {
if (core != nullptr) {
if (core->c > 1) {
core->c--;
} else {
delete (core);
}
}
if (other != nullptr) {
core = new Core(other);
} else {
core = nullptr;
}
return *this;
}
~SmartPointer() {
if (core != nullptr) {
core = nullptr;
}
}
// return reference to the object of class/type T
// if SmartPointer contains nullptr throw `SmartPointer::exception`
value_type& operator*() {
if (core == nullptr) {
throw smart_pointer::exception();
}
return *core->p;
}
const value_type& operator*() const {
if (core == nullptr) {
throw smart_pointer::exception();
}
return *core->p;
}
// return pointer to the object of class/type T
value_type* operator->() const {
if (core != nullptr) {
return core->p;
}
return nullptr;
}
value_type* get() const {
if (core != nullptr) {
return core->p;
}
return nullptr;
}
// if pointer == nullptr => return false
explicit operator bool() const {
return (core != nullptr);
}
// if pointers points to the same address or both null => true
template <typename U, typename AnotherAllocator>
bool operator==(const SmartPointer<U, AnotherAllocator>& other) const {
if (core != nullptr) {
return (core->p == reinterpret_cast<value_type*>(other.get()));
} else {
return (other.get() == nullptr);
}
}
// if pointers points to the same address or both null => false
template <typename U, typename AnotherAllocator>
bool operator!=(const SmartPointer<U, AnotherAllocator>& other) const {
return !(*this == other);
}
// if smart pointer contains non-nullptr => return count owners
// if smart pointer contains nullptr => return 0
std::size_t count_owners() const {
if (core == nullptr) {
return 0;
}
return core->c;
}
private:
class Core {
public:
explicit Core(value_type* x) : p(x) {}
size_t c = 0;
value_type* p;
};
Core* core;
};
}