1 //
2 // Tests for
3 //  template<typename To, typename From, typename R>
4 //  intrusive_shared_ptr<To, R> reinterpret_pointer_cast(intrusive_shared_ptr<From, R> const& ptr) noexcept;
5 //
6 //  template<typename To, typename From, typename R>
7 //  intrusive_shared_ptr<To, R> reinterpret_pointer_cast(intrusive_shared_ptr<From, R>&& ptr) noexcept
8 //
9 
10 #include <libkern/c++/intrusive_shared_ptr.h>
11 #include <utility>
12 #include <darwintest.h>
13 #include "test_policy.h"
14 
15 struct Base { int i; };
16 struct Derived : Base { };
17 
18 // Layout compatible with Derived
19 struct Unrelated { int i; };
20 
21 template <typename Stored, typename From, typename To>
22 static void
23 tests()
24 {
25 	Stored obj{3};
26 
27 	{
28 		tracked_shared_ptr<From> const from(&obj, libkern::no_retain);
29 		tracking_policy::reset();
30 		tracked_shared_ptr<To> to = libkern::reinterpret_pointer_cast<To>(from);
31 		CHECK(tracking_policy::retains == 1);
32 		CHECK(tracking_policy::releases == 0);
33 		CHECK(to.get() == reinterpret_cast<To const*>(&obj));
34 		CHECK(from.get() == &obj);
35 	}
36 	{
37 		tracked_shared_ptr<From> from(&obj, libkern::no_retain);
38 		tracking_policy::reset();
39 		tracked_shared_ptr<To> to = libkern::reinterpret_pointer_cast<To>(std::move(from));
40 		CHECK(tracking_policy::retains == 0);
41 		CHECK(tracking_policy::releases == 0);
42 		CHECK(to.get() == reinterpret_cast<To const*>(&obj));
43 		CHECK(from.get() == nullptr);
44 	}
45 
46 	// Test `reinterpret_pointer_cast`ing a null pointer
47 	{
48 		tracked_shared_ptr<From> const from = nullptr;
49 		tracking_policy::reset();
50 		tracked_shared_ptr<To> to = libkern::reinterpret_pointer_cast<To>(from);
51 		CHECK(tracking_policy::retains == 0);
52 		CHECK(tracking_policy::releases == 0);
53 		CHECK(to.get() == nullptr);
54 		CHECK(from.get() == nullptr);
55 	}
56 	{
57 		tracked_shared_ptr<From> from = nullptr;
58 		tracking_policy::reset();
59 		tracked_shared_ptr<To> to = libkern::reinterpret_pointer_cast<To>(std::move(from));
60 		CHECK(tracking_policy::retains == 0);
61 		CHECK(tracking_policy::releases == 0);
62 		CHECK(to.get() == nullptr);
63 		CHECK(from.get() == nullptr);
64 	}
65 }
66 
67 T_DECL(cast_reinterpret, "intrusive_shared_ptr.cast.reinterpret") {
68 	tests</*stored*/ Derived, /*from*/ Derived, /*to*/ Base>();
69 	tests</*stored*/ Derived, /*from*/ Derived const, /*to*/ Base const>();
70 
71 	tests</*stored*/ Derived, /*from*/ Derived, /*to*/ char>();
72 	tests</*stored*/ Derived, /*from*/ Derived const, /*to*/ char const>();
73 
74 	tests</*stored*/ Derived, /*from*/ Derived, /*to*/ Unrelated>();
75 	tests</*stored*/ Derived, /*from*/ Derived const, /*to*/ Unrelated const>();
76 }
77