simplify copy_ptr

include/libtorrent/copy_ptr.hpp

@@ -33,46 +33,34 @@ POSSIBILITY OF SUCH DAMAGE.
 #ifndef TORRENT_COPY_PTR
 #define TORRENT_COPY_PTR
 
+#include <memory>
+
 namespace libtorrent {
 
 	template <class T>
 	struct copy_ptr
 	{
-		copy_ptr(): m_ptr(nullptr) {}
+		copy_ptr() = default;
 		explicit copy_ptr(T* t): m_ptr(t) {}
 		copy_ptr(copy_ptr const& p): m_ptr(p.m_ptr ? new T(*p.m_ptr) : nullptr) {}
-		copy_ptr(copy_ptr&& p) noexcept : m_ptr(p.m_ptr) { p.m_ptr = nullptr; }
+		copy_ptr(copy_ptr&& p) noexcept = default;
 
-		void reset(T* t = nullptr) { delete m_ptr; m_ptr = t; }
+		void reset(T* t = nullptr) { m_ptr.reset(t); }
 		copy_ptr& operator=(copy_ptr const& p)
 		{
 			if (m_ptr == p.m_ptr) return *this;
-			T* c = p.m_ptr ? new T(*p.m_ptr) : nullptr;
-			delete m_ptr;
-			m_ptr = c;
+			m_ptr.reset(p.m_ptr ? new T(*p.m_ptr) : nullptr);
 			return *this;
 		}
-		copy_ptr& operator=(copy_ptr&& p) noexcept {
-			if(m_ptr == p.m_ptr) return *this;
-			delete m_ptr;
-			m_ptr = p.m_ptr;
-			p.m_ptr = nullptr;
-			return *this;
-		}
-		T* operator->() { return m_ptr; }
-		T const* operator->() const { return m_ptr; }
+		copy_ptr& operator=(copy_ptr&& p) noexcept = default;
+		T* operator->() { return m_ptr.get(); }
+		T const* operator->() const { return m_ptr.get(); }
 		T& operator*() { return *m_ptr; }
 		T const& operator*() const { return *m_ptr; }
-		void swap(copy_ptr<T>& p)
-		{
-			T* tmp = m_ptr;
-			m_ptr = p.m_ptr;
-			p.m_ptr = tmp;
-		}
-		explicit operator bool() const { return m_ptr != nullptr; }
-		~copy_ptr() { delete m_ptr; }
+		void swap(copy_ptr<T>& p) { std::swap(*this, p); }
+		explicit operator bool() const { return m_ptr.get() != nullptr; }
 	private:
-		T* m_ptr = nullptr;
+		std::unique_ptr<T> m_ptr;
 	};
 }
 

test/test_torrent_info.cpp

@@ -1008,3 +1008,19 @@ TORRENT_TEST(copy)
 		TEST_EQUAL(fs2.hash(i), file_hashes[i]);
 	}
 }
+
+struct A
+{
+	int val;
+};
+
+TORRENT_TEST(copy_ptr)
+{
+	copy_ptr<A> a(new A{4});
+	copy_ptr<A> b(a);
+
+	TEST_EQUAL(a->val, b->val);
+	TEST_CHECK(&*a != &*b);
+	a->val = 5;
+	TEST_EQUAL(b->val, 4);
+}