xref: /freebsd/contrib/kyua/utils/noncopyable.hpp (revision b13788e396c2b24f88697e7d4a74bab429ef4d0c)
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28 
29 /// \file utils/noncopyable.hpp
30 /// Provides the utils::noncopyable class.
31 ///
32 /// The class is provided as a separate module on its own to minimize
33 /// header-inclusion side-effects.
34 
35 #if !defined(UTILS_NONCOPYABLE_HPP)
36 #define UTILS_NONCOPYABLE_HPP
37 
38 
39 namespace utils {
40 
41 
42 /// Forbids copying a class at compile-time.
43 ///
44 /// Inheriting from this class delivers a private copy constructor and an
45 /// assignment operator that effectively forbid copying the class during
46 /// compilation.
47 ///
48 /// Always use private inheritance.
49 class noncopyable {
50     /// Data placeholder.
51     ///
52     /// The class cannot be empty; otherwise we get ABI-stability warnings
53     /// during the build, which will break it due to strict checking.
54     int _noncopyable_dummy;
55 
56     /// Private copy constructor to deny copying of subclasses.
57     noncopyable(const noncopyable&);
58 
59     /// Private assignment constructor to deny copying of subclasses.
60     ///
61     /// \return A reference to the object.
62     noncopyable& operator=(const noncopyable&);
63 
64 protected:
65     // Explicitly needed to provide some non-private functions.  Otherwise
66     // we also get some warnings during the build.
67     noncopyable(void) {}
68     ~noncopyable(void) {}
69 };
70 
71 
72 }  // namespace utils
73 
74 
75 #endif  // !defined(UTILS_NONCOPYABLE_HPP)
76