1 //===--- AvoidCArraysCheck.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 "AvoidCArraysCheck.h"
10 #include "clang/AST/ASTContext.h"
11 #include "clang/ASTMatchers/ASTMatchFinder.h"
12
13 using namespace clang::ast_matchers;
14
15 namespace {
16
AST_MATCHER(clang::TypeLoc,hasValidBeginLoc)17 AST_MATCHER(clang::TypeLoc, hasValidBeginLoc) {
18 return Node.getBeginLoc().isValid();
19 }
20
AST_MATCHER_P(clang::TypeLoc,hasType,clang::ast_matchers::internal::Matcher<clang::Type>,InnerMatcher)21 AST_MATCHER_P(clang::TypeLoc, hasType,
22 clang::ast_matchers::internal::Matcher<clang::Type>,
23 InnerMatcher) {
24 const clang::Type *TypeNode = Node.getTypePtr();
25 return TypeNode != nullptr &&
26 InnerMatcher.matches(*TypeNode, Finder, Builder);
27 }
28
AST_MATCHER(clang::RecordDecl,isExternCContext)29 AST_MATCHER(clang::RecordDecl, isExternCContext) {
30 return Node.isExternCContext();
31 }
32
AST_MATCHER(clang::ParmVarDecl,isArgvOfMain)33 AST_MATCHER(clang::ParmVarDecl, isArgvOfMain) {
34 const clang::DeclContext *DC = Node.getDeclContext();
35 const auto *FD = llvm::dyn_cast<clang::FunctionDecl>(DC);
36 return FD ? FD->isMain() : false;
37 }
38
39 } // namespace
40
41 namespace clang {
42 namespace tidy {
43 namespace modernize {
44
registerMatchers(MatchFinder * Finder)45 void AvoidCArraysCheck::registerMatchers(MatchFinder *Finder) {
46 Finder->addMatcher(
47 typeLoc(hasValidBeginLoc(), hasType(arrayType()),
48 unless(anyOf(hasParent(parmVarDecl(isArgvOfMain())),
49 hasParent(varDecl(isExternC())),
50 hasParent(fieldDecl(
51 hasParent(recordDecl(isExternCContext())))),
52 hasAncestor(functionDecl(isExternC())))))
53 .bind("typeloc"),
54 this);
55 }
56
check(const MatchFinder::MatchResult & Result)57 void AvoidCArraysCheck::check(const MatchFinder::MatchResult &Result) {
58 const auto *ArrayType = Result.Nodes.getNodeAs<TypeLoc>("typeloc");
59
60 static constexpr llvm::StringLiteral UseArray = llvm::StringLiteral(
61 "do not declare C-style arrays, use std::array<> instead");
62 static constexpr llvm::StringLiteral UseVector = llvm::StringLiteral(
63 "do not declare C VLA arrays, use std::vector<> instead");
64
65 diag(ArrayType->getBeginLoc(),
66 ArrayType->getTypePtr()->isVariableArrayType() ? UseVector : UseArray);
67 }
68
69 } // namespace modernize
70 } // namespace tidy
71 } // namespace clang
72