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
registerMatchers(MatchFinder * Finder)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
check(const MatchFinder::MatchResult & Result)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
registerPPCallbacks(const SourceManager & SM,Preprocessor * Pp,Preprocessor * ModuleExpanderPP)66 void BadSignalToKillThreadCheck::registerPPCallbacks(
67 const SourceManager &SM, Preprocessor *Pp, Preprocessor *ModuleExpanderPP) {
68 PP = Pp;
69 }
70
71 } // namespace clang::tidy::bugprone
72