1 //===--- SetLongJmpCheck.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 "SetLongJmpCheck.h"
10 #include "clang/AST/ASTContext.h"
11 #include "clang/ASTMatchers/ASTMatchFinder.h"
12 #include "clang/Frontend/CompilerInstance.h"
13 #include "clang/Lex/PPCallbacks.h"
14 #include "clang/Lex/Preprocessor.h"
15
16 using namespace clang::ast_matchers;
17
18 namespace clang::tidy::cert {
19
20 namespace {
21 const char DiagWording[] =
22 "do not call %0; consider using exception handling instead";
23
24 class SetJmpMacroCallbacks : public PPCallbacks {
25 SetLongJmpCheck &Check;
26
27 public:
SetJmpMacroCallbacks(SetLongJmpCheck & Check)28 explicit SetJmpMacroCallbacks(SetLongJmpCheck &Check) : Check(Check) {}
29
MacroExpands(const Token & MacroNameTok,const MacroDefinition & MD,SourceRange Range,const MacroArgs * Args)30 void MacroExpands(const Token &MacroNameTok, const MacroDefinition &MD,
31 SourceRange Range, const MacroArgs *Args) override {
32 const auto *II = MacroNameTok.getIdentifierInfo();
33 if (!II)
34 return;
35
36 if (II->getName() == "setjmp")
37 Check.diag(Range.getBegin(), DiagWording) << II;
38 }
39 };
40 } // namespace
41
registerPPCallbacks(const SourceManager & SM,Preprocessor * PP,Preprocessor * ModuleExpanderPP)42 void SetLongJmpCheck::registerPPCallbacks(const SourceManager &SM,
43 Preprocessor *PP,
44 Preprocessor *ModuleExpanderPP) {
45 // Per [headers]p5, setjmp must be exposed as a macro instead of a function,
46 // despite the allowance in C for setjmp to also be an extern function.
47 PP->addPPCallbacks(std::make_unique<SetJmpMacroCallbacks>(*this));
48 }
49
registerMatchers(MatchFinder * Finder)50 void SetLongJmpCheck::registerMatchers(MatchFinder *Finder) {
51 // In case there is an implementation that happens to define setjmp as a
52 // function instead of a macro, this will also catch use of it. However, we
53 // are primarily searching for uses of longjmp.
54 Finder->addMatcher(
55 callExpr(callee(functionDecl(hasAnyName("setjmp", "longjmp"))))
56 .bind("expr"),
57 this);
58 }
59
check(const MatchFinder::MatchResult & Result)60 void SetLongJmpCheck::check(const MatchFinder::MatchResult &Result) {
61 const auto *E = Result.Nodes.getNodeAs<CallExpr>("expr");
62 diag(E->getExprLoc(), DiagWording) << cast<NamedDecl>(E->getCalleeDecl());
63 }
64
65 } // namespace clang::tidy::cert
66