libcamera  v0.3.0+92-226ce294
Supporting cameras in Linux since 2019
unique_fd.h
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1 /* SPDX-License-Identifier: LGPL-2.1-or-later */
2 /*
3  * Copyright (C) 2021, Google Inc.
4  *
5  * File descriptor wrapper that owns a file descriptor.
6  */
7 
8 #pragma once
9 
10 #include <utility>
11 
12 #include <libcamera/base/class.h>
13 #include <libcamera/base/compiler.h>
14 
15 namespace libcamera {
16 
17 class UniqueFD final
18 {
19 public:
21  : fd_(-1)
22  {
23  }
24 
25  explicit UniqueFD(int fd)
26  : fd_(fd)
27  {
28  }
29 
30  UniqueFD(UniqueFD &&other)
31  : fd_(other.release())
32  {
33  }
34 
36  {
37  reset();
38  }
39 
41  {
42  reset(other.release());
43  return *this;
44  }
45 
46  __nodiscard int release()
47  {
48  int fd = fd_;
49  fd_ = -1;
50  return fd;
51  }
52 
53  void reset(int fd = -1);
54 
55  void swap(UniqueFD &other)
56  {
57  std::swap(fd_, other.fd_);
58  }
59 
60  int get() const { return fd_; }
61  bool isValid() const { return fd_ >= 0; }
62 
63 private:
65 
66  int fd_;
67 };
68 
69 } /* namespace libcamera */
UniqueFD(UniqueFD &&other)
Move constructor, create a UniqueFD by taking over other.
Definition: unique_fd.h:30
Utilities to help constructing class interfaces.
UniqueFD()
Construct a UniqueFD that owns no file descriptor.
Definition: unique_fd.h:20
void swap(UniqueFD &other)
Swap the managed file descriptors with another UniqueFD.
Definition: unique_fd.h:55
Top-level libcamera namespace.
Definition: backtrace.h:17
#define LIBCAMERA_DISABLE_COPY(klass)
Disable copy construction and assignment of the klass.
unique_ptr-like wrapper for a file descriptor
Definition: unique_fd.h:17
UniqueFD(int fd)
Construct a UniqueFD that owns fd.
Definition: unique_fd.h:25
bool isValid() const
Check if the UniqueFD owns a valid file descriptor.
Definition: unique_fd.h:61
void reset(int fd=-1)
Replace the managed file descriptor.
Definition: unique_fd.cpp:95
UniqueFD & operator=(UniqueFD &&other)
Move assignment operator, replace a UniqueFD by taking over other.
Definition: unique_fd.h:40
__nodiscard int release()
Release ownership of the file descriptor without closing it.
Definition: unique_fd.h:46
~UniqueFD()
Destroy the UniqueFD instance.
Definition: unique_fd.h:35