clang-tools 6.0.0

MisplacedOperatorInStrlenInAllocCheck.cpp
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1 //===--- MisplacedOperatorInStrlenInAllocCheck.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 "MisplacedOperatorInStrlenInAllocCheck.h"
11 #include "clang/AST/ASTContext.h"
12 #include "clang/ASTMatchers/ASTMatchFinder.h"
13
14 using namespace clang::ast_matchers;
15
16 namespace clang {
17 namespace tidy {
18 namespace bugprone {
19
20 void MisplacedOperatorInStrlenInAllocCheck::registerMatchers(
21 MatchFinder *Finder) {
22 const auto StrLenFunc = functionDecl(anyOf(
23 hasName("::strlen"), hasName("::std::strlen"), hasName("::strnlen"),
24 hasName("::std::strnlen"), hasName("::strnlen_s"),
25 hasName("::std::strnlen_s"), hasName("::wcslen"),
26 hasName("::std::wcslen"), hasName("::wcsnlen"), hasName("::std::wcsnlen"),
27 hasName("::wcsnlen_s"), hasName("std::wcsnlen_s")));
28
29 const auto BadUse =
30 callExpr(callee(StrLenFunc),
31 hasAnyArgument(ignoringImpCasts(
32 binaryOperator(allOf(hasOperatorName("+"),
33 hasRHS(ignoringParenImpCasts(
34 integerLiteral(equals(1))))))
35 .bind("BinOp"))))
36 .bind("StrLen");
37
38 const auto BadArg = anyOf(
39 allOf(hasDescendant(BadUse),
40 unless(binaryOperator(allOf(
41 hasOperatorName("+"), hasLHS(BadUse),
42 hasRHS(ignoringParenImpCasts(integerLiteral(equals(1)))))))),
43 BadUse);
44
45 const auto Alloc0Func =
46 functionDecl(anyOf(hasName("::malloc"), hasName("std::malloc"),
47 hasName("::alloca"), hasName("std::alloca")));
48 const auto Alloc1Func =
49 functionDecl(anyOf(hasName("::calloc"), hasName("std::calloc"),
50 hasName("::realloc"), hasName("std::realloc")));
51
52 const auto Alloc0FuncPtr =
53 varDecl(hasType(isConstQualified()),
54 hasInitializer(ignoringParenImpCasts(
55 declRefExpr(hasDeclaration(Alloc0Func)))));
56 const auto Alloc1FuncPtr =
57 varDecl(hasType(isConstQualified()),
58 hasInitializer(ignoringParenImpCasts(
59 declRefExpr(hasDeclaration(Alloc1Func)))));
60
61 Finder->addMatcher(callExpr(callee(decl(anyOf(Alloc0Func, Alloc0FuncPtr))),
62 hasArgument(0, BadArg))
63 .bind("Alloc"),
64 this);
65 Finder->addMatcher(callExpr(callee(decl(anyOf(Alloc1Func, Alloc1FuncPtr))),
66 hasArgument(1, BadArg))
67 .bind("Alloc"),
68 this);
69 Finder->addMatcher(
70 cxxNewExpr(isArray(), hasArraySize(BadArg)).bind("Alloc"), this);
71 }
72
73 void MisplacedOperatorInStrlenInAllocCheck::check(
74 const MatchFinder::MatchResult &Result) {
75 const Expr *Alloc = Result.Nodes.getNodeAs<CallExpr>("Alloc");
76 if (!Alloc)
77 Alloc = Result.Nodes.getNodeAs<CXXNewExpr>("Alloc");
78 assert(Alloc && "Matched node bound by 'Alloc' shoud be either 'CallExpr'"
79 " or 'CXXNewExpr'");
80
81 const auto *StrLen = Result.Nodes.getNodeAs<CallExpr>("StrLen");
82 const auto *BinOp = Result.Nodes.getNodeAs<BinaryOperator>("BinOp");
83
84 const StringRef StrLenText = Lexer::getSourceText(
85 CharSourceRange::getTokenRange(StrLen->getSourceRange()),
86 *Result.SourceManager, getLangOpts());
87 const StringRef Arg0Text = Lexer::getSourceText(
88 CharSourceRange::getTokenRange(StrLen->getArg(0)->getSourceRange()),
89 *Result.SourceManager, getLangOpts());
90 const StringRef StrLenBegin = StrLenText.substr(0, StrLenText.find(Arg0Text));
91 const StringRef StrLenEnd = StrLenText.substr(
92 StrLenText.find(Arg0Text) + Arg0Text.size(), StrLenText.size());
93
94 const StringRef LHSText = Lexer::getSourceText(
95 CharSourceRange::getTokenRange(BinOp->getLHS()->getSourceRange()),
96 *Result.SourceManager, getLangOpts());
97 const StringRef RHSText = Lexer::getSourceText(
98 CharSourceRange::getTokenRange(BinOp->getRHS()->getSourceRange()),
99 *Result.SourceManager, getLangOpts());
100
101 auto Hint = FixItHint::CreateReplacement(
102 StrLen->getSourceRange(),
103 (StrLenBegin + LHSText + StrLenEnd + " + " + RHSText).str());
104
105 diag(Alloc->getLocStart(),
106 "addition operator is applied to the argument of %0 instead of its "
107 "result") << StrLen->getDirectCallee()->getName() << Hint;
108 }
109
110 } // namespace bugprone
111 } // namespace tidy
112 } // namespace clang
clang::ast_matchers
Definition: ClangTidyDiagnosticConsumer.h:27
MisplacedOperatorInStrlenInAllocCheck.h
clang
Definition: AndroidTidyModule.cpp:28