blob: 3476e0210a557b3369727018c1acb07b52a2dcc9 (
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
|
// Copyright 2017 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifndef UI_BASE_GLIB_SCOPED_GOBJECT_H_
#define UI_BASE_GLIB_SCOPED_GOBJECT_H_
#include <glib-object.h>
#include "base/check.h"
#include "base/memory/raw_ptr.h"
// Similar to a std::shared_ptr for GObject types.
template <typename T>
class ScopedGObject {
public:
ScopedGObject() = default;
ScopedGObject(const ScopedGObject<T>& other) : obj_(other.obj_) { Ref(); }
ScopedGObject(ScopedGObject<T>&& other) : obj_(other.obj_) {
other.obj_ = nullptr;
}
~ScopedGObject() { Unref(); }
ScopedGObject<T>& operator=(const ScopedGObject<T>& other) {
Unref();
obj_ = other.obj_;
Ref();
return *this;
}
ScopedGObject<T>& operator=(ScopedGObject<T>&& other) {
Unref();
obj_ = other.obj_;
other.obj_ = nullptr;
return *this;
}
T* get() { return obj_; }
operator T*() { return obj_; }
private:
template <typename U>
friend ScopedGObject<U> TakeGObject(U* obj);
template <typename U>
friend ScopedGObject<U> WrapGObject(U* obj);
explicit ScopedGObject(T* obj) : obj_(obj) {}
void RefSink() {
// Remove the floating reference from |obj_| if it has one.
if (obj_ && g_object_is_floating(obj_))
g_object_ref_sink(obj_);
}
void Ref() {
if (obj_) {
DCHECK(!g_object_is_floating(obj_));
g_object_ref(obj_);
}
}
// This function is necessary so that gtk can overload it in
// the case of T = GtkStyleContext.
void Unref() {
if (obj_)
g_object_unref(obj_);
}
raw_ptr<T> obj_ = nullptr;
};
// Create a ScopedGObject and do not increase the GObject's reference count.
// This is usually used to reference a newly-created GObject, which are created
// with a reference count of 1 by default.
template <typename T>
ScopedGObject<T> TakeGObject(T* obj) {
ScopedGObject<T> scoped(obj);
scoped.RefSink();
return scoped;
}
// Create a ScopedGObject and increase the GObject's reference count by 1.
// This is usually used to reference an existing GObject.
template <typename T>
ScopedGObject<T> WrapGObject(T* obj) {
ScopedGObject<T> scoped(obj);
scoped.Ref();
return scoped;
}
#endif // UI_BASE_GLIB_SCOPED_GOBJECT_H_
|