clang-tools-extra/clang-tidy/utils/HeaderGuard.h

   1 //===--- HeaderGuard.h - clang-tidy -----------------------------*- 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 LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_UTILS_HEADERGUARD_H
  10 #define LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_UTILS_HEADERGUARD_H
  11
  12 #include "../ClangTidyCheck.h"
  13 #include "../utils/FileExtensionsUtils.h"
  14
  15 namespace clang::tidy::utils {
  16
  17 /// Finds and fixes header guards.
  18 /// The check supports these options:
  19 ///   - `HeaderFileExtensions`: a semicolon-separated list of filename
  20 ///     extensions of header files (The filename extension should not contain
  21 ///     "." prefix). ";h;hh;hpp;hxx" by default.
  22 ///
  23 ///     For extension-less header files, using an empty string or leaving an
  24 ///     empty string between ";" if there are other filename extensions.
  25 class HeaderGuardCheck : public ClangTidyCheck {
  26 public:
  27   HeaderGuardCheck(StringRef Name, ClangTidyContext *Context)
  28       : ClangTidyCheck(Name, Context) {
  29     std::optional<StringRef> HeaderFileExtensionsOption =
  30         Options.get("HeaderFileExtensions");
  31     RawStringHeaderFileExtensions = HeaderFileExtensionsOption.value_or(
  32         utils::defaultHeaderFileExtensions());
  33     if (HeaderFileExtensionsOption) {
  34       if (!utils::parseFileExtensions(
  35               RawStringHeaderFileExtensions, HeaderFileExtensions,
  36               utils::defaultFileExtensionDelimiters())) {
  37         this->configurationDiag("Invalid header file extension: '%0'")
  38             << RawStringHeaderFileExtensions;
  39       }
  40     } else
  41       HeaderFileExtensions = Context->getHeaderFileExtensions();
  42   }
  43   void storeOptions(ClangTidyOptions::OptionMap &Opts) override;
  44   void registerPPCallbacks(const SourceManager &SM, Preprocessor *PP,
  45                            Preprocessor *ModuleExpanderPP) override;
  46
  47   /// Ensure that the provided header guard is a non-reserved identifier.
  48   std::string sanitizeHeaderGuard(StringRef Guard);
  49
  50   /// Returns ``true`` if the check should suggest inserting a trailing comment
  51   /// on the ``#endif`` of the header guard. It will use the same name as
  52   /// returned by ``HeaderGuardCheck::getHeaderGuard``.
  53   virtual bool shouldSuggestEndifComment(StringRef Filename);
  54   /// Returns ``true`` if the check should suggest changing an existing header
  55   /// guard to the string returned by ``HeaderGuardCheck::getHeaderGuard``.
  56   virtual bool shouldFixHeaderGuard(StringRef Filename);
  57   /// Returns ``true`` if the check should add a header guard to the file
  58   /// if it has none.
  59   virtual bool shouldSuggestToAddHeaderGuard(StringRef Filename);
  60   /// Returns a replacement for the ``#endif`` line with a comment mentioning
  61   /// \p HeaderGuard. The replacement should start with ``endif``.
  62   virtual std::string formatEndIf(StringRef HeaderGuard);
  63   /// Gets the canonical header guard for a file.
  64   virtual std::string getHeaderGuard(StringRef Filename,
  65                                      StringRef OldGuard = StringRef()) = 0;
  66
  67 private:
  68   std::string RawStringHeaderFileExtensions;
  69   FileExtensionsSet HeaderFileExtensions;
  70 };
  71
  72 } // namespace clang::tidy::utils
  73
  74 #endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_UTILS_HEADERGUARD_H