clang-tools-extra/clang-tidy/bugprone/BadSignalToKillThreadCheck.cpp

   1 //===--- BadSignalToKillThreadCheck.cpp - clang-tidy ---------------------===//
   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 #include "BadSignalToKillThreadCheck.h"
  10 #include "clang/AST/ASTContext.h"
  11 #include "clang/ASTMatchers/ASTMatchFinder.h"
  12 #include "clang/Lex/Preprocessor.h"
  13 #include <optional>
  14
  15 using namespace clang::ast_matchers;
  16
  17 namespace clang::tidy::bugprone {
  18
  19 void BadSignalToKillThreadCheck::registerMatchers(MatchFinder *Finder) {
  20   Finder->addMatcher(
  21       callExpr(callee(functionDecl(hasName("::pthread_kill"))),
  22                argumentCountIs(2),
  23                hasArgument(1, integerLiteral().bind("integer-literal")))
  24           .bind("thread-kill"),
  25       this);
  26 }
  27
  28 static Preprocessor *PP;
  29
  30 void BadSignalToKillThreadCheck::check(const MatchFinder::MatchResult &Result) {
  31   const auto IsSigterm = [](const auto &KeyValue) -> bool {
  32     return KeyValue.first->getName() == "SIGTERM" &&
  33            KeyValue.first->hasMacroDefinition();
  34   };
  35   const auto TryExpandAsInteger =
  36       [](Preprocessor::macro_iterator It) -> std::optional<unsigned> {
  37     if (It == PP->macro_end())
  38       return std::nullopt;
  39     const MacroInfo *MI = PP->getMacroInfo(It->first);
  40     const Token &T = MI->tokens().back();
  41     if (!T.isLiteral() || !T.getLiteralData())
  42       return std::nullopt;
  43     StringRef ValueStr = StringRef(T.getLiteralData(), T.getLength());
  44
  45     llvm::APInt IntValue;
  46     constexpr unsigned AutoSenseRadix = 0;
  47     if (ValueStr.getAsInteger(AutoSenseRadix, IntValue))
  48       return std::nullopt;
  49     return IntValue.getZExtValue();
  50   };
  51
  52   const auto SigtermMacro = llvm::find_if(PP->macros(), IsSigterm);
  53
  54   if (!SigtermValue && !(SigtermValue = TryExpandAsInteger(SigtermMacro)))
  55     return;
  56
  57   const auto *MatchedExpr = Result.Nodes.getNodeAs<Expr>("thread-kill");
  58   const auto *MatchedIntLiteral =
  59       Result.Nodes.getNodeAs<IntegerLiteral>("integer-literal");
  60   if (MatchedIntLiteral->getValue() == *SigtermValue) {
  61     diag(MatchedExpr->getBeginLoc(),
  62          "thread should not be terminated by raising the 'SIGTERM' signal");
  63   }
  64 }
  65
  66 void BadSignalToKillThreadCheck::registerPPCallbacks(
  67     const SourceManager &SM, Preprocessor *Pp, Preprocessor *ModuleExpanderPP) {
  68   PP = Pp;
  69 }
  70
  71 } // namespace clang::tidy::bugprone