1 //===--- ImplementationInNamespaceCheck.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 "ImplementationInNamespaceCheck.h"
10 #include "clang/AST/ASTContext.h"
11 #include "clang/ASTMatchers/ASTMatchFinder.h"
12 
13 using namespace clang::ast_matchers;
14 
15 namespace clang {
16 namespace tidy {
17 namespace llvm_libc {
18 
19 const static StringRef RequiredNamespace = "__llvm_libc";
registerMatchers(MatchFinder * Finder)20 void ImplementationInNamespaceCheck::registerMatchers(MatchFinder *Finder) {
21   Finder->addMatcher(
22       decl(hasParent(translationUnitDecl()), unless(linkageSpecDecl()))
23           .bind("child_of_translation_unit"),
24       this);
25 }
26 
check(const MatchFinder::MatchResult & Result)27 void ImplementationInNamespaceCheck::check(
28     const MatchFinder::MatchResult &Result) {
29   const auto *MatchedDecl =
30       Result.Nodes.getNodeAs<Decl>("child_of_translation_unit");
31   if (!Result.SourceManager->isInMainFile(MatchedDecl->getLocation()))
32     return;
33 
34   if (const auto *NS = dyn_cast<NamespaceDecl>(MatchedDecl)) {
35     if (NS->getName() != RequiredNamespace) {
36       diag(NS->getLocation(), "'%0' needs to be the outermost namespace")
37           << RequiredNamespace;
38     }
39     return;
40   }
41   diag(MatchedDecl->getLocation(),
42        "declaration must be declared within the '%0' namespace")
43       << RequiredNamespace;
44   return;
45 }
46 
47 } // namespace llvm_libc
48 } // namespace tidy
49 } // namespace clang
50