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
|
/*
*
* Copyright 2017 gRPC authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
*/
#ifndef GRPC_CORE_LIB_GPRPP_ORPHANABLE_H
#define GRPC_CORE_LIB_GPRPP_ORPHANABLE_H
#include <grpc/support/port_platform.h>
#include <grpc/support/log.h>
#include <grpc/support/sync.h>
#include <cinttypes>
#include <memory>
#include "src/core/lib/debug/trace.h"
#include "src/core/lib/gprpp/abstract.h"
#include "src/core/lib/gprpp/debug_location.h"
#include "src/core/lib/gprpp/memory.h"
#include "src/core/lib/gprpp/ref_counted.h"
#include "src/core/lib/gprpp/ref_counted_ptr.h"
namespace grpc_core {
// A base class for orphanable objects, which have one external owner
// but are not necessarily destroyed immediately when the external owner
// gives up ownership. Instead, the owner calls the object's Orphan()
// method, and the object then takes responsibility for its own cleanup
// and destruction.
class Orphanable {
public:
// Gives up ownership of the object. The implementation must arrange
// to eventually destroy the object without further interaction from the
// caller.
virtual void Orphan() GRPC_ABSTRACT;
// Not copyable or movable.
Orphanable(const Orphanable&) = delete;
Orphanable& operator=(const Orphanable&) = delete;
GRPC_ABSTRACT_BASE_CLASS
protected:
Orphanable() {}
virtual ~Orphanable() {}
};
template <typename T>
class OrphanableDelete {
public:
void operator()(T* p) { p->Orphan(); }
};
template <typename T, typename Deleter = OrphanableDelete<T>>
using OrphanablePtr = std::unique_ptr<T, Deleter>;
template <typename T, typename... Args>
inline OrphanablePtr<T> MakeOrphanable(Args&&... args) {
return OrphanablePtr<T>(New<T>(std::forward<Args>(args)...));
}
// A type of Orphanable with internal ref-counting.
template <typename Child>
class InternallyRefCounted : public Orphanable {
public:
// Not copyable nor movable.
InternallyRefCounted(const InternallyRefCounted&) = delete;
InternallyRefCounted& operator=(const InternallyRefCounted&) = delete;
GRPC_ABSTRACT_BASE_CLASS
protected:
GPRC_ALLOW_CLASS_TO_USE_NON_PUBLIC_DELETE
// Allow RefCountedPtr<> to access Unref() and IncrementRefCount().
template <typename T>
friend class RefCountedPtr;
// TraceFlagT is defined to accept both DebugOnlyTraceFlag and TraceFlag.
// Note: RefCount tracing is only enabled on debug builds, even when a
// TraceFlag is used.
template <typename TraceFlagT = TraceFlag>
explicit InternallyRefCounted(TraceFlagT* trace_flag = nullptr)
: refs_(1, trace_flag) {}
virtual ~InternallyRefCounted() = default;
RefCountedPtr<Child> Ref() GRPC_MUST_USE_RESULT {
IncrementRefCount();
return RefCountedPtr<Child>(static_cast<Child*>(this));
}
RefCountedPtr<Child> Ref(const DebugLocation& location,
const char* reason) GRPC_MUST_USE_RESULT {
IncrementRefCount(location, reason);
return RefCountedPtr<Child>(static_cast<Child*>(this));
}
void Unref() {
if (refs_.Unref()) {
Delete(static_cast<Child*>(this));
}
}
void Unref(const DebugLocation& location, const char* reason) {
if (refs_.Unref(location, reason)) {
Delete(static_cast<Child*>(this));
}
}
private:
void IncrementRefCount() { refs_.Ref(); }
void IncrementRefCount(const DebugLocation& location, const char* reason) {
refs_.Ref(location, reason);
}
grpc_core::RefCount refs_;
};
} // namespace grpc_core
#endif /* GRPC_CORE_LIB_GPRPP_ORPHANABLE_H */
|
