1 | //===-- Flags.h -------------------------------------------------*- C++ -*-===// |
2 | // |
3 | // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
4 | // See https://llvm.org/LICENSE.txt for license information. |
5 | // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
6 | // |
7 | //===----------------------------------------------------------------------===// |
8 | |
9 | #ifndef LLDB_UTILITY_FLAGS_H |
10 | #define LLDB_UTILITY_FLAGS_H |
11 | |
12 | #include <cstddef> |
13 | #include <cstdint> |
14 | |
15 | namespace lldb_private { |
16 | |
17 | /// \class Flags Flags.h "lldb/Utility/Flags.h" |
18 | /// A class to manage flags. |
19 | /// |
20 | /// The Flags class managed flag bits and allows testing and modification of |
21 | /// individual or multiple flag bits. |
22 | class Flags { |
23 | public: |
24 | /// The value type for flags is a 32 bit unsigned integer type. |
25 | typedef uint32_t ValueType; |
26 | |
27 | /// Construct with initial flag bit values. |
28 | /// |
29 | /// Constructs this object with \a mask as the initial value for all of the |
30 | /// flags. |
31 | /// |
32 | /// \param[in] flags |
33 | /// The initial value for all flags. |
34 | Flags(ValueType flags = 0) : m_flags(flags) {} |
35 | |
36 | /// Get accessor for all flags. |
37 | /// |
38 | /// \return |
39 | /// Returns all of the flags as a Flags::ValueType. |
40 | ValueType Get() const { return m_flags; } |
41 | |
42 | /// Return the number of flags that can be represented in this object. |
43 | /// |
44 | /// \return |
45 | /// The maximum number bits in this flag object. |
46 | size_t GetBitSize() const { return sizeof(ValueType) * 8; } |
47 | |
48 | /// Set accessor for all flags. |
49 | /// |
50 | /// \param[in] flags |
51 | /// The bits with which to replace all of the current flags. |
52 | void Reset(ValueType flags) { m_flags = flags; } |
53 | |
54 | /// Clear one or more flags. |
55 | /// |
56 | /// \param[in] mask |
57 | /// A bitfield containing one or more flags. |
58 | /// |
59 | /// \return |
60 | /// The new flags after clearing all bits from \a mask. |
61 | ValueType Clear(ValueType mask = ~static_cast<ValueType>(0)) { |
62 | m_flags &= ~mask; |
63 | return m_flags; |
64 | } |
65 | |
66 | /// Set one or more flags by logical OR'ing \a mask with the current flags. |
67 | /// |
68 | /// \param[in] mask |
69 | /// A bitfield containing one or more flags. |
70 | /// |
71 | /// \return |
72 | /// The new flags after setting all bits from \a mask. |
73 | ValueType Set(ValueType mask) { |
74 | m_flags |= mask; |
75 | return m_flags; |
76 | } |
77 | |
78 | /// Test if all bits in \a mask are 1 in the current flags |
79 | /// |
80 | /// \return |
81 | /// \b true if all flags in \a mask are 1, \b false |
82 | /// otherwise. |
83 | bool AllSet(ValueType mask) const { return (m_flags & mask) == mask; } |
84 | |
85 | /// Test one or more flags. |
86 | /// |
87 | /// \return |
88 | /// \b true if any flags in \a mask are 1, \b false |
89 | /// otherwise. |
90 | bool AnySet(ValueType mask) const { return (m_flags & mask) != 0; } |
91 | |
92 | /// Test a single flag bit. |
93 | /// |
94 | /// \return |
95 | /// \b true if \a bit is set, \b false otherwise. |
96 | bool Test(ValueType bit) const { return (m_flags & bit) != 0; } |
97 | |
98 | /// Test if all bits in \a mask are clear. |
99 | /// |
100 | /// \return |
101 | /// \b true if \b all flags in \a mask are clear, \b false |
102 | /// otherwise. |
103 | bool AllClear(ValueType mask) const { return (m_flags & mask) == 0; } |
104 | |
105 | bool AnyClear(ValueType mask) const { return (m_flags & mask) != mask; } |
106 | |
107 | /// Test a single flag bit to see if it is clear (zero). |
108 | /// |
109 | /// \return |
110 | /// \b true if \a bit is 0, \b false otherwise. |
111 | bool IsClear(ValueType bit) const { return (m_flags & bit) == 0; } |
112 | |
113 | protected: |
114 | ValueType m_flags; ///< The flags. |
115 | }; |
116 | |
117 | } // namespace lldb_private |
118 | |
119 | #endif // LLDB_UTILITY_FLAGS_H |
120 | |