| 3 | |
| 4 | template<typename T> |
| 5 | class Ref { |
| 6 | T* ptr = nullptr; |
| 7 | public: |
| 8 | //default constructor |
| 9 | Ref() : ptr(nullptr) {} |
| 10 | |
| 11 | /** |
| 12 | @returns if this ref is a null ref |
| 13 | */ |
| 14 | bool isNull() { |
| 15 | return ptr == nullptr; |
| 16 | } |
| 17 | |
| 18 | /** |
| 19 | Makes this ref object a null ref. Releases any previously held pointer. |
| 20 | */ |
| 21 | void setNull() { |
| 22 | if (!isNull()) { |
| 23 | ptr->release(); |
| 24 | } |
| 25 | ptr = nullptr; |
| 26 | } |
| 27 | |
| 28 | //constructor |
| 29 | Ref(T* const other) { |
| 30 | other->retain(); |
| 31 | ptr = other; |
| 32 | } |
| 33 | |
| 34 | //construct from weak pointer |
| 35 | Ref(const WeakRef<T>& other) : Ref(other.get()) {}; |
| 36 | |
| 37 | //copy |
| 38 | Ref(const Ref<T>& other) : Ref(other.ptr) {} |
| 39 | |
| 40 | //destructor |
| 41 | //if this crashes, I have a bug because the object was released too early |
| 42 | virtual ~Ref() { |
| 43 | if (!isNull()) { |
| 44 | ptr->release(); |
| 45 | } |
| 46 | } |
| 47 | |
| 48 | //copy assignment |
| 49 | Ref<T>& operator=(const Ref<T>& other) { |
| 50 | if (&other == this) { |
| 51 | return *this; |
| 52 | } |
| 53 | //copy pointer and increment its retain |
| 54 | if (!isNull()) { |
| 55 | ptr->release(); |
| 56 | } |
| 57 | ptr = other.get(); |
| 58 | if (ptr != nullptr) { |
| 59 | ptr->retain(); |
| 60 | } |
| 61 | return *this; |
| 62 | } |