| 1 | //===--- SignalHandlerCheck.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_BUGPRONE_SIGNALHANDLERCHECK_H |
| 10 | #define LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_BUGPRONE_SIGNALHANDLERCHECK_H |
| 11 | |
| 12 | #include "../ClangTidyCheck.h" |
| 13 | #include "clang/Analysis/CallGraph.h" |
| 14 | #include "llvm/ADT/DepthFirstIterator.h" |
| 15 | #include "llvm/ADT/StringSet.h" |
| 16 | |
| 17 | namespace clang::tidy::bugprone { |
| 18 | |
| 19 | /// Checker for signal handler functions. |
| 20 | /// |
| 21 | /// For the user-facing documentation see: |
| 22 | /// http://clang.llvm.org/extra/clang-tidy/checks/bugprone/signal-handler.html |
| 23 | class SignalHandlerCheck : public ClangTidyCheck { |
| 24 | public: |
| 25 | enum class AsyncSafeFunctionSetKind { Minimal, POSIX }; |
| 26 | |
| 27 | SignalHandlerCheck(StringRef Name, ClangTidyContext *Context); |
| 28 | void storeOptions(ClangTidyOptions::OptionMap &Opts) override; |
| 29 | bool isLanguageVersionSupported(const LangOptions &LangOpts) const override; |
| 30 | void registerMatchers(ast_matchers::MatchFinder *Finder) override; |
| 31 | void check(const ast_matchers::MatchFinder::MatchResult &Result) override; |
| 32 | |
| 33 | private: |
| 34 | /// Check if a function is allowed as a signal handler. |
| 35 | /// Should test the properties of the function, and check in the code body. |
| 36 | /// Should not check function calls in the code (this part is done by the call |
| 37 | /// graph scan). |
| 38 | /// Bug reports are generated for the whole code body (no stop at the first |
| 39 | /// found issue). For issues that are not in the code body, only one |
| 40 | /// bug report is generated. |
| 41 | /// \param FD The function to check. It may or may not have a definition. |
| 42 | /// \param CallOrRef Location of the call to this function (in another |
| 43 | /// function) or the reference to the function (if it is used as a registered |
| 44 | /// signal handler). This is the location where diagnostics are to be placed. |
| 45 | /// \param ChainReporter A function that adds bug report notes to display the |
| 46 | /// chain of called functions from signal handler registration to the current |
| 47 | /// function. This is called at every generated bug report. |
| 48 | /// The bool parameter is used like \c SkipPathEnd in \c reportHandlerChain . |
| 49 | /// \return Returns true if a diagnostic was emitted for this function. |
| 50 | bool checkFunction(const FunctionDecl *FD, const Expr *CallOrRef, |
| 51 | std::function<void(bool)> ChainReporter); |
| 52 | /// Similar as \c checkFunction but only check for C++14 rules. |
| 53 | bool checkFunctionCPP14(const FunctionDecl *FD, const Expr *CallOrRef, |
| 54 | std::function<void(bool)> ChainReporter); |
| 55 | /// Returns true if a standard library function is considered |
| 56 | /// asynchronous-safe. |
| 57 | bool isStandardFunctionAsyncSafe(const FunctionDecl *FD) const; |
| 58 | /// Add diagnostic notes to show the call chain of functions from a signal |
| 59 | /// handler to a function that is called (directly or indirectly) from it. |
| 60 | /// Also add a note to the place where the signal handler is registered. |
| 61 | /// @param Itr Position during a call graph depth-first iteration. It contains |
| 62 | /// the "path" (call chain) from the signal handler to the actual found |
| 63 | /// function call. |
| 64 | /// @param HandlerRef Reference to the signal handler function where it is |
| 65 | /// registered as signal handler. |
| 66 | /// @param SkipPathEnd If true the last item of the call chain (farthest away |
| 67 | /// from the \c signal call) is omitted from note generation. |
| 68 | void reportHandlerChain(const llvm::df_iterator<clang::CallGraphNode *> &Itr, |
| 69 | const DeclRefExpr *HandlerRef, bool SkipPathEnd); |
| 70 | |
| 71 | clang::CallGraph CG; |
| 72 | |
| 73 | AsyncSafeFunctionSetKind AsyncSafeFunctionSet; |
| 74 | llvm::StringSet<> ConformingFunctions; |
| 75 | }; |
| 76 | |
| 77 | } // namespace clang::tidy::bugprone |
| 78 | |
| 79 | #endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_BUGPRONE_SIGNALHANDLERCHECK_H |
| 80 | |