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
|
// Copyright 2018 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifndef PLATFORM_IMPL_SCOPED_PIPE_H_
#define PLATFORM_IMPL_SCOPED_PIPE_H_
#include <unistd.h>
#include <utility>
namespace openscreen {
struct IntFdTraits {
using PipeType = int;
static constexpr int kInvalidValue = -1;
static void Close(PipeType pipe) { close(pipe); }
};
// This class wraps file descriptor and uses RAII to ensure it is closed
// properly when control leaves its scope. It is parameterized by a traits type
// which defines the value type of the file descriptor, an invalid value, and a
// closing function.
//
// This class is move-only as it represents ownership of the wrapped file
// descriptor. It is not thread-safe.
template <typename Traits>
class ScopedPipe {
public:
using PipeType = typename Traits::PipeType;
ScopedPipe() : pipe_(Traits::kInvalidValue) {}
explicit ScopedPipe(PipeType pipe) : pipe_(pipe) {}
ScopedPipe(const ScopedPipe&) = delete;
ScopedPipe(ScopedPipe&& other) : pipe_(other.release()) {}
~ScopedPipe() {
if (pipe_ != Traits::kInvalidValue)
Traits::Close(release());
}
ScopedPipe& operator=(ScopedPipe&& other) {
if (pipe_ != Traits::kInvalidValue)
Traits::Close(release());
pipe_ = other.release();
return *this;
}
PipeType get() const { return pipe_; }
PipeType release() {
PipeType pipe = pipe_;
pipe_ = Traits::kInvalidValue;
return pipe;
}
bool operator==(const ScopedPipe& other) const {
return pipe_ == other.pipe_;
}
bool operator!=(const ScopedPipe& other) const { return !(*this == other); }
explicit operator bool() const { return pipe_ != Traits::kInvalidValue; }
private:
PipeType pipe_;
};
using ScopedFd = ScopedPipe<IntFdTraits>;
} // namespace openscreen
#endif // PLATFORM_IMPL_SCOPED_PIPE_H_
|
