void SuspiciousEnumUsageCheck::registerMatchers(MatchFinder *Finder) {
const auto enumExpr = [](StringRef RefName, StringRef DeclName) {
return allOf(ignoringImpCasts(expr().bind(RefName)),
ignoringImpCasts(hasType(enumDecl().bind(DeclName))));
};
Finder->addMatcher(
binaryOperator(hasOperatorName("|"), hasLHS(enumExpr("", "enumDecl")),
hasRHS(allOf(enumExpr("", "otherEnumDecl"),
ignoringImpCasts(hasType(enumDecl(
unless(equalsBoundNode("enumDecl"))))))))
.bind("diffEnumOp"),
this);
Finder->addMatcher(
binaryOperator(anyOf(hasOperatorName("+"), hasOperatorName("|")),
hasLHS(enumExpr("lhsExpr", "enumDecl")),
hasRHS(allOf(enumExpr("rhsExpr", ""),
ignoringImpCasts(hasType(enumDecl(
equalsBoundNode("enumDecl"))))))),
this);
Finder->addMatcher(
binaryOperator(anyOf(hasOperatorName("+"), hasOperatorName("|")),
hasEitherOperand(
allOf(hasType(isInteger()), unless(enumExpr("", "")))),
hasEitherOperand(enumExpr("enumExpr", "enumDecl"))),
this);
Finder->addMatcher(
binaryOperator(anyOf(hasOperatorName("|="), hasOperatorName("+=")),
hasRHS(enumExpr("enumExpr", "enumDecl"))),
this);
}
void DeleteNullPointerCheck::registerMatchers(MatchFinder *Finder) {
const auto DeleteExpr =
cxxDeleteExpr(has(castExpr(has(declRefExpr(
to(decl(equalsBoundNode("deletedPointer"))))))))
.bind("deleteExpr");
const auto DeleteMemberExpr =
cxxDeleteExpr(has(castExpr(has(memberExpr(hasDeclaration(
fieldDecl(equalsBoundNode("deletedMemberPointer"))))))))
.bind("deleteMemberExpr");
const auto PointerExpr = ignoringImpCasts(anyOf(
declRefExpr(to(decl().bind("deletedPointer"))),
memberExpr(hasDeclaration(fieldDecl().bind("deletedMemberPointer")))));
const auto PointerCondition = castExpr(hasCastKind(CK_PointerToBoolean),
hasSourceExpression(PointerExpr));
const auto BinaryPointerCheckCondition =
binaryOperator(hasEitherOperand(castExpr(hasCastKind(CK_NullToPointer))),
hasEitherOperand(PointerExpr));
Finder->addMatcher(
ifStmt(hasCondition(anyOf(PointerCondition, BinaryPointerCheckCondition)),
hasThen(anyOf(
DeleteExpr, DeleteMemberExpr,
compoundStmt(anyOf(has(DeleteExpr), has(DeleteMemberExpr)),
statementCountIs(1))
.bind("compound"))))
.bind("ifWithDelete"),
this);
}
void ContainerSizeEmptyCheck::registerMatchers(MatchFinder *Finder) {
const auto WrongUse = anyOf(
hasParent(
binaryOperator(
anyOf(has(integerLiteral(equals(0))),
allOf(anyOf(hasOperatorName("<"), hasOperatorName(">="),
hasOperatorName(">"), hasOperatorName("<=")),
hasEitherOperand(integerLiteral(equals(1))))))
.bind("SizeBinaryOp")),
hasParent(implicitCastExpr(
hasImplicitDestinationType(isBoolType()),
anyOf(
hasParent(unaryOperator(hasOperatorName("!")).bind("NegOnSize")),
anything()))),
hasParent(explicitCastExpr(hasDestinationType(isBoolType()))));
Finder->addMatcher(
memberCallExpr(
on(expr(anyOf(hasType(namedDecl(stlContainer())),
hasType(pointsTo(namedDecl(stlContainer()))),
hasType(references(namedDecl(stlContainer())))))
.bind("STLObject")),
callee(methodDecl(hasName("size"))), WrongUse).bind("SizeCallExpr"),
this);
}
void SignedBitwiseCheck::registerMatchers(MatchFinder *Finder) {
const auto SignedIntegerOperand =
expr(ignoringImpCasts(hasType(isSignedInteger()))).bind("signed-operand");
// The standard [bitmask.types] allows some integral types to be implemented
// as signed types. Exclude these types from diagnosing for bitwise or(|) and
// bitwise and(&). Shifting and complementing such values is still not
// allowed.
const auto BitmaskType = namedDecl(anyOf(
hasName("::std::locale::category"), hasName("::std::ctype_base::mask"),
hasName("::std::ios_base::fmtflags"), hasName("::std::ios_base::iostate"),
hasName("::std::ios_base::openmode")));
const auto IsStdBitmask = ignoringImpCasts(declRefExpr(hasType(BitmaskType)));
// Match binary bitwise operations on signed integer arguments.
Finder->addMatcher(
binaryOperator(
allOf(anyOf(hasOperatorName("^"), hasOperatorName("|"),
hasOperatorName("&"), hasOperatorName("^="),
hasOperatorName("|="), hasOperatorName("&=")),
unless(allOf(hasLHS(IsStdBitmask), hasRHS(IsStdBitmask))),
hasEitherOperand(SignedIntegerOperand),
hasLHS(hasType(isInteger())), hasRHS(hasType(isInteger()))))
.bind("binary-no-sign-interference"),
this);
// Shifting and complement is not allowed for any signed integer type because
// the sign bit may corrupt the result.
Finder->addMatcher(
binaryOperator(
allOf(anyOf(hasOperatorName("<<"), hasOperatorName(">>"),
hasOperatorName("<<="), hasOperatorName(">>=")),
hasEitherOperand(SignedIntegerOperand),
hasLHS(hasType(isInteger())), hasRHS(hasType(isInteger()))))
.bind("binary-sign-interference"),
this);
// Match unary operations on signed integer types.
Finder->addMatcher(unaryOperator(allOf(hasOperatorName("~"),
hasUnaryOperand(SignedIntegerOperand)))
.bind("unary-signed"),
this);
}
void DurationAdditionCheck::registerMatchers(MatchFinder *Finder) {
Finder->addMatcher(
binaryOperator(hasOperatorName("+"),
hasEitherOperand(expr(ignoringParenImpCasts(
callExpr(callee(functionDecl(TimeConversionFunction())
.bind("function_decl")))
.bind("call")))))
.bind("binop"),
this);
}
void PointerAndIntegralOperationCheck::registerMatchers(MatchFinder *Finder) {
const auto PointerExpr = expr(hasType(pointerType()));
const auto BoolExpr = ignoringParenImpCasts(hasType(booleanType()));
const auto CharExpr = ignoringParenImpCasts(hasType(isAnyCharacter()));
const auto BinOpWithPointerExpr =
binaryOperator(unless(anyOf(hasOperatorName(","), hasOperatorName("="))),
hasEitherOperand(PointerExpr));
const auto AssignToPointerExpr =
binaryOperator(hasOperatorName("="), hasLHS(PointerExpr));
const auto CompareToPointerExpr =
binaryOperator(matchers::isRelationalOperator(),
hasEitherOperand(PointerExpr));
// Detect expression like: ptr = (x != y);
Finder->addMatcher(binaryOperator(AssignToPointerExpr, hasRHS(BoolExpr))
.bind("assign-bool-to-pointer"),
this);
// Detect expression like: ptr = A[i]; where A is char*.
Finder->addMatcher(binaryOperator(AssignToPointerExpr, hasRHS(CharExpr))
.bind("assign-char-to-pointer"),
this);
// Detect expression like: ptr < false;
Finder->addMatcher(
binaryOperator(BinOpWithPointerExpr,
hasEitherOperand(ignoringParenImpCasts(cxxBoolLiteral())))
.bind("pointer-and-bool-literal"),
this);
// Detect expression like: ptr < 'a';
Finder->addMatcher(binaryOperator(BinOpWithPointerExpr,
hasEitherOperand(ignoringParenImpCasts(
characterLiteral())))
.bind("pointer-and-char-literal"),
this);
// Detect expression like: ptr < 0;
Finder->addMatcher(binaryOperator(CompareToPointerExpr,
hasEitherOperand(ignoringParenImpCasts(
integerLiteral(equals(0)))))
.bind("compare-pointer-to-zero"),
this);
// Detect expression like: ptr < nullptr;
Finder->addMatcher(binaryOperator(CompareToPointerExpr,
hasEitherOperand(ignoringParenImpCasts(
cxxNullPtrLiteralExpr())))
.bind("compare-pointer-to-null"),
this);
}
void ContainerSizeEmptyCheck::registerMatchers(MatchFinder *Finder) {
// Only register the matchers for C++; the functionality currently does not
// provide any benefit to other languages, despite being benign.
if (!getLangOpts().CPlusPlus)
return;
const auto ValidContainer = cxxRecordDecl(isSameOrDerivedFrom(
namedDecl(
has(cxxMethodDecl(
isConst(), parameterCountIs(0), isPublic(), hasName("size"),
returns(qualType(isInteger(), unless(booleanType()))))
.bind("size")),
has(cxxMethodDecl(isConst(), parameterCountIs(0), isPublic(),
hasName("empty"), returns(booleanType()))
.bind("empty")))
.bind("container")));
const auto WrongUse = anyOf(
hasParent(binaryOperator(
matchers::isComparisonOperator(),
hasEitherOperand(ignoringImpCasts(anyOf(
integerLiteral(equals(1)), integerLiteral(equals(0))))))
.bind("SizeBinaryOp")),
hasParent(implicitCastExpr(
hasImplicitDestinationType(booleanType()),
anyOf(
hasParent(unaryOperator(hasOperatorName("!")).bind("NegOnSize")),
anything()))),
hasParent(explicitCastExpr(hasDestinationType(booleanType()))));
Finder->addMatcher(
cxxMemberCallExpr(on(expr(anyOf(hasType(ValidContainer),
hasType(pointsTo(ValidContainer)),
hasType(references(ValidContainer))))
.bind("STLObject")),
callee(cxxMethodDecl(hasName("size"))), WrongUse)
.bind("SizeCallExpr"),
this);
}
void MisplacedWideningCastCheck::registerMatchers(MatchFinder *Finder) {
const auto Calc =
expr(anyOf(binaryOperator(
anyOf(hasOperatorName("+"), hasOperatorName("-"),
hasOperatorName("*"), hasOperatorName("<<"))),
unaryOperator(hasOperatorName("~"))),
hasType(isInteger()))
.bind("Calc");
const auto ExplicitCast = explicitCastExpr(hasDestinationType(isInteger()),
has(ignoringParenImpCasts(Calc)));
const auto ImplicitCast =
implicitCastExpr(hasImplicitDestinationType(isInteger()),
has(ignoringParenImpCasts(Calc)));
const auto Cast = expr(anyOf(ExplicitCast, ImplicitCast)).bind("Cast");
Finder->addMatcher(varDecl(hasInitializer(Cast)), this);
Finder->addMatcher(returnStmt(hasReturnValue(Cast)), this);
Finder->addMatcher(callExpr(hasAnyArgument(Cast)), this);
Finder->addMatcher(binaryOperator(hasOperatorName("="), hasRHS(Cast)), this);
Finder->addMatcher(
binaryOperator(matchers::isComparisonOperator(), hasEitherOperand(Cast)),
this);
}
void SuspiciousStringCompareCheck::registerMatchers(MatchFinder *Finder) {
// Match relational operators.
const auto ComparisonUnaryOperator = unaryOperator(hasOperatorName("!"));
const auto ComparisonBinaryOperator =
binaryOperator(matchers::isComparisonOperator());
const auto ComparisonOperator =
expr(anyOf(ComparisonUnaryOperator, ComparisonBinaryOperator));
// Add the list of known string compare-like functions and add user-defined
// functions.
std::vector<std::string> FunctionNames = utils::options::parseStringList(
(llvm::Twine(KnownStringCompareFunctions) + StringCompareLikeFunctions)
.str());
// Match a call to a string compare functions.
const auto FunctionCompareDecl =
functionDecl(hasAnyName(std::vector<StringRef>(FunctionNames.begin(),
FunctionNames.end())))
.bind("decl");
const auto DirectStringCompareCallExpr =
callExpr(hasDeclaration(FunctionCompareDecl)).bind("call");
const auto MacroStringCompareCallExpr = conditionalOperator(anyOf(
hasTrueExpression(ignoringParenImpCasts(DirectStringCompareCallExpr)),
hasFalseExpression(ignoringParenImpCasts(DirectStringCompareCallExpr))));
// The implicit cast is not present in C.
const auto StringCompareCallExpr = ignoringParenImpCasts(
anyOf(DirectStringCompareCallExpr, MacroStringCompareCallExpr));
if (WarnOnImplicitComparison) {
// Detect suspicious calls to string compare:
// 'if (strcmp())' -> 'if (strcmp() != 0)'
Finder->addMatcher(
stmt(anyOf(ifStmt(hasCondition(StringCompareCallExpr)),
whileStmt(hasCondition(StringCompareCallExpr)),
doStmt(hasCondition(StringCompareCallExpr)),
forStmt(hasCondition(StringCompareCallExpr)),
binaryOperator(
anyOf(hasOperatorName("&&"), hasOperatorName("||")),
hasEitherOperand(StringCompareCallExpr))))
.bind("missing-comparison"),
this);
}
if (WarnOnLogicalNotComparison) {
// Detect suspicious calls to string compared with '!' operator:
// 'if (!strcmp())' -> 'if (strcmp() == 0)'
Finder->addMatcher(unaryOperator(hasOperatorName("!"),
hasUnaryOperand(ignoringParenImpCasts(
StringCompareCallExpr)))
.bind("logical-not-comparison"),
this);
}
// Detect suspicious cast to an inconsistant type (i.e. not integer type).
Finder->addMatcher(
implicitCastExpr(unless(hasType(isInteger())),
hasSourceExpression(StringCompareCallExpr))
.bind("invalid-conversion"),
this);
// Detect suspicious operator with string compare function as operand.
Finder->addMatcher(
binaryOperator(
unless(anyOf(matchers::isComparisonOperator(), hasOperatorName("&&"),
hasOperatorName("||"), hasOperatorName("="))),
hasEitherOperand(StringCompareCallExpr))
.bind("suspicious-operator"),
this);
// Detect comparison to invalid constant: 'strcmp() == -1'.
const auto InvalidLiteral = ignoringParenImpCasts(
anyOf(integerLiteral(unless(equals(0))),
unaryOperator(
hasOperatorName("-"),
has(ignoringParenImpCasts(integerLiteral(unless(equals(0)))))),
characterLiteral(), cxxBoolLiteral()));
Finder->addMatcher(binaryOperator(matchers::isComparisonOperator(),
hasEitherOperand(StringCompareCallExpr),
hasEitherOperand(InvalidLiteral))
.bind("invalid-comparison"),
this);
}
