1 //===-- RegularExpression.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_REGULAREXPRESSION_H
10 #define LLDB_UTILITY_REGULAREXPRESSION_H
11 
12 #include "llvm/ADT/StringRef.h"
13 #include "llvm/Support/Error.h"
14 #include "llvm/Support/Regex.h"
15 
16 namespace lldb_private {
17 
18 class RegularExpression {
19 public:
20   /// The default constructor that initializes the object state such that it
21   /// contains no compiled regular expression.
22   RegularExpression() = default;
23 
24   /// Constructor for a regular expression.
25   ///
26   /// Compile a regular expression using the supplied regular expression text.
27   /// The compiled regular expression lives in this object so that it can be
28   /// readily used for regular expression matches. Execute() can be called
29   /// after the regular expression is compiled.
30   ///
31   /// \param[in] string
32   ///     An llvm::StringRef that represents the regular expression to compile.
33   //      String is not referenced anymore after the object is constructed.
34   explicit RegularExpression(llvm::StringRef string);
35 
36   ~RegularExpression() = default;
37 
38   RegularExpression(const RegularExpression &rhs);
39   RegularExpression(RegularExpression &&rhs) = default;
40 
41   RegularExpression &operator=(RegularExpression &&rhs) = default;
42   RegularExpression &operator=(const RegularExpression &rhs) = default;
43 
44   /// Execute a regular expression match using the compiled regular expression
45   /// that is already in this object against the given \a string. If any parens
46   /// are used for regular expression matches.
47   ///
48   /// \param[in] string
49   ///     The string to match against the compile regular expression.
50   ///
51   /// \param[out] matches
52   ///     A pointer to a SmallVector to hold the matches.
53   ///
54   /// \return
55   ///     true if \a string matches the compiled regular expression, false
56   ///     otherwise incl. the case regular exression failed to compile.
57   bool Execute(llvm::StringRef string,
58                llvm::SmallVectorImpl<llvm::StringRef> *matches = nullptr) const;
59 
60   /// Access the regular expression text.
61   ///
62   /// \return
63   ///     The NULL terminated C string that was used to compile the
64   ///     current regular expression
65   llvm::StringRef GetText() const;
66 
67   /// Test if this object contains a valid regular expression.
68   ///
69   /// \return
70   ///     true if the regular expression compiled and is ready for execution,
71   ///     false otherwise.
72   bool IsValid() const;
73 
74   /// Return an error if the regular expression failed to compile.
75   ///
76   /// \return
77   ///     A string error if the regular expression failed to compile, success
78   ///     otherwise.
79   llvm::Error GetError() const;
80 
81   bool operator==(const RegularExpression &rhs) const {
82     return GetText() == rhs.GetText();
83   }
84 
85 private:
86   /// A copy of the original regular expression text.
87   std::string m_regex_text;
88   /// The compiled regular expression.
89   mutable llvm::Regex m_regex;
90 };
91 
92 } // namespace lldb_private
93 
94 #endif // LLDB_UTILITY_REGULAREXPRESSION_H
95