1 //===--- CloexecSocketCheck.cpp - clang-tidy-------------------------------===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 
10 #include "CloexecSocketCheck.h"
11 #include "../utils/ASTUtils.h"
12 #include "clang/AST/ASTContext.h"
13 #include "clang/ASTMatchers/ASTMatchFinder.h"
14 
15 using namespace clang::ast_matchers;
16 
17 namespace clang {
18 namespace tidy {
19 namespace android {
20 
21 static constexpr const char *SOCK_CLOEXEC = "SOCK_CLOEXEC";
22 
23 void CloexecSocketCheck::registerMatchers(MatchFinder *Finder) {
24   Finder->addMatcher(
25       callExpr(callee(functionDecl(isExternC(), returns(isInteger()),
26                                    hasName("socket"),
27                                    hasParameter(0, hasType(isInteger())),
28                                    hasParameter(1, hasType(isInteger())),
29                                    hasParameter(2, hasType(isInteger())))
30                           .bind("funcDecl")))
31           .bind("socketFn"),
32       this);
33 }
34 
35 void CloexecSocketCheck::check(const MatchFinder::MatchResult &Result) {
36   const auto *MatchedCall = Result.Nodes.getNodeAs<CallExpr>("socketFn");
37   const auto *FD = Result.Nodes.getNodeAs<FunctionDecl>("funcDecl");
38   const Expr *FlagArg = MatchedCall->getArg(1);
39   SourceManager &SM = *Result.SourceManager;
40 
41   if (utils::exprHasBitFlagWithSpelling(FlagArg->IgnoreParenCasts(), SM,
42                      Result.Context->getLangOpts(), SOCK_CLOEXEC))
43     return;
44 
45   SourceLocation EndLoc =
46       Lexer::getLocForEndOfToken(SM.getFileLoc(FlagArg->getLocEnd()), 0, SM,
47                                  Result.Context->getLangOpts());
48 
49   diag(EndLoc, "%0 should use %1 where possible")
50       << FD << SOCK_CLOEXEC
51       << FixItHint::CreateInsertion(EndLoc,
52                                     (Twine(" | ") + SOCK_CLOEXEC).str());
53 }
54 
55 } // namespace android
56 } // namespace tidy
57 } // namespace clang
58