summaryrefslogtreecommitdiff
path: root/AK/OwnPtr.h
blob: 4f6b1fbc64ac0a5b297291ee5ed98117de82eb42 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
/*
 * Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
 *
 * SPDX-License-Identifier: BSD-2-Clause
 */

#pragma once

#include <AK/Error.h>
#include <AK/NonnullOwnPtr.h>
#include <AK/RefCounted.h>

#define OWNPTR_SCRUB_BYTE 0xf0

namespace AK {

template<typename T>
class [[nodiscard]] OwnPtr {
public:
    OwnPtr() = default;

    OwnPtr(decltype(nullptr))
        : m_ptr(nullptr)
    {
    }

    OwnPtr(OwnPtr&& other)
        : m_ptr(other.leak_ptr())
    {
    }

    template<typename U>
    OwnPtr(NonnullOwnPtr<U>&& other)
        : m_ptr(other.leak_ptr())
    {
    }
    template<typename U>
    OwnPtr(OwnPtr<U>&& other)
        : m_ptr(other.leak_ptr())
    {
    }
    ~OwnPtr()
    {
        clear();
#ifdef SANITIZE_PTRS
        m_ptr = (T*)(explode_byte(OWNPTR_SCRUB_BYTE));
#endif
    }

    OwnPtr(OwnPtr const&) = delete;
    template<typename U>
    OwnPtr(OwnPtr<U> const&) = delete;
    OwnPtr& operator=(OwnPtr const&) = delete;
    template<typename U>
    OwnPtr& operator=(OwnPtr<U> const&) = delete;

    template<typename U>
    OwnPtr(NonnullOwnPtr<U> const&) = delete;
    template<typename U>
    OwnPtr& operator=(NonnullOwnPtr<U> const&) = delete;
    template<typename U>
    OwnPtr(RefPtr<U> const&) = delete;
    template<typename U>
    OwnPtr(NonnullRefPtr<U> const&) = delete;
    template<typename U>
    OwnPtr(WeakPtr<U> const&) = delete;
    template<typename U>
    OwnPtr& operator=(RefPtr<U> const&) = delete;
    template<typename U>
    OwnPtr& operator=(NonnullRefPtr<U> const&) = delete;
    template<typename U>
    OwnPtr& operator=(WeakPtr<U> const&) = delete;

    OwnPtr& operator=(OwnPtr&& other)
    {
        OwnPtr ptr(move(other));
        swap(ptr);
        return *this;
    }

    template<typename U>
    OwnPtr& operator=(OwnPtr<U>&& other)
    {
        OwnPtr ptr(move(other));
        swap(ptr);
        return *this;
    }

    template<typename U>
    OwnPtr& operator=(NonnullOwnPtr<U>&& other)
    {
        OwnPtr ptr(move(other));
        swap(ptr);
        VERIFY(m_ptr);
        return *this;
    }

    OwnPtr& operator=(T* ptr) = delete;

    OwnPtr& operator=(std::nullptr_t)
    {
        clear();
        return *this;
    }

    void clear()
    {
        delete m_ptr;
        m_ptr = nullptr;
    }

    bool operator!() const { return !m_ptr; }

    [[nodiscard]] T* leak_ptr()
    {
        T* leaked_ptr = m_ptr;
        m_ptr = nullptr;
        return leaked_ptr;
    }

    NonnullOwnPtr<T> release_nonnull()
    {
        VERIFY(m_ptr);
        return NonnullOwnPtr<T>(NonnullOwnPtr<T>::Adopt, *leak_ptr());
    }

    template<typename U>
    NonnullOwnPtr<U> release_nonnull()
    {
        VERIFY(m_ptr);
        return NonnullOwnPtr<U>(NonnullOwnPtr<U>::Adopt, static_cast<U&>(*leak_ptr()));
    }

    T* ptr() { return m_ptr; }
    const T* ptr() const { return m_ptr; }

    T* operator->()
    {
        VERIFY(m_ptr);
        return m_ptr;
    }

    const T* operator->() const
    {
        VERIFY(m_ptr);
        return m_ptr;
    }

    T& operator*()
    {
        VERIFY(m_ptr);
        return *m_ptr;
    }

    const T& operator*() const
    {
        VERIFY(m_ptr);
        return *m_ptr;
    }

    operator const T*() const { return m_ptr; }
    operator T*() { return m_ptr; }

    operator bool() { return !!m_ptr; }

    void swap(OwnPtr& other)
    {
        ::swap(m_ptr, other.m_ptr);
    }

    template<typename U>
    void swap(OwnPtr<U>& other)
    {
        ::swap(m_ptr, other.m_ptr);
    }

    static OwnPtr lift(T* ptr)
    {
        return OwnPtr { ptr };
    }

protected:
    explicit OwnPtr(T* ptr)
        : m_ptr(ptr)
    {
        static_assert(
            requires { requires typename T::AllowOwnPtr()(); } || !requires { requires !typename T::AllowOwnPtr()(); declval<T>().ref(); declval<T>().unref(); }, "Use RefPtr<> for RefCounted types");
    }

private:
    T* m_ptr = nullptr;
};

template<typename T, typename U>
inline void swap(OwnPtr<T>& a, OwnPtr<U>& b)
{
    a.swap(b);
}

template<typename T>
inline OwnPtr<T> adopt_own_if_nonnull(T* object)
{
    if (object)
        return OwnPtr<T>::lift(object);
    return {};
}

template<typename T>
inline ErrorOr<NonnullOwnPtr<T>> adopt_nonnull_own_or_enomem(T* object)
{
    auto result = adopt_own_if_nonnull(object);
    if (!result)
        return Error::from_errno(ENOMEM);
    return result.release_nonnull();
}

template<typename T, class... Args>
requires(IsConstructible<T, Args...>) inline ErrorOr<NonnullOwnPtr<T>> try_make(Args&&... args)
{
    return adopt_nonnull_own_or_enomem(new (nothrow) T(forward<Args>(args)...));
}

// FIXME: Remove once P0960R3 is available in Clang.
template<typename T, class... Args>
inline ErrorOr<NonnullOwnPtr<T>> try_make(Args&&... args)

{
    return adopt_nonnull_own_or_enomem(new (nothrow) T { forward<Args>(args)... });
}

template<typename T>
struct Traits<OwnPtr<T>> : public GenericTraits<OwnPtr<T>> {
    using PeekType = T*;
    using ConstPeekType = const T*;
    static unsigned hash(OwnPtr<T> const& p) { return ptr_hash(p.ptr()); }
    static bool equals(OwnPtr<T> const& a, OwnPtr<T> const& b) { return a.ptr() == b.ptr(); }
};

}

using AK::adopt_nonnull_own_or_enomem;
using AK::adopt_own_if_nonnull;
using AK::OwnPtr;
using AK::try_make;