1 /*
2     This file is part of the clazy static checker.
3 
4     Copyright (C) 2015 Klarälvdalens Datakonsult AB, a KDAB Group company, info@kdab.com
5     Author: Sérgio Martins <sergio.martins@kdab.com>
6 
7     Copyright (C) 2015 Sergio Martins <smartins@kde.org>
8 
9     This library is free software; you can redistribute it and/or
10     modify it under the terms of the GNU Library General Public
11     License as published by the Free Software Foundation; either
12     version 2 of the License, or (at your option) any later version.
13 
14     This library is distributed in the hope that it will be useful,
15     but WITHOUT ANY WARRANTY; without even the implied warranty of
16     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
17     Library General Public License for more details.
18 
19     You should have received a copy of the GNU Library General Public License
20     along with this library; see the file COPYING.LIB.  If not, write to
21     the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
22     Boston, MA 02110-1301, USA.
23 */
24 
25 #include "assert-with-side-effects.h"
26 #include "MacroUtils.h"
27 #include "StringUtils.h"
28 #include "SourceCompatibilityHelpers.h"
29 #include "clazy_stl.h"
30 
31 #include <clang/AST/Expr.h>
32 #include <clang/AST/Stmt.h>
33 #include <clang/AST/Decl.h>
34 #include <clang/AST/DeclCXX.h>
35 #include <clang/AST/ExprCXX.h>
36 #include <clang/AST/OperationKinds.h>
37 #include <clang/Basic/LLVM.h>
38 #include <clang/Basic/SourceLocation.h>
39 #include <clang/Basic/SourceManager.h>
40 #include <llvm/ADT/StringRef.h>
41 #include <llvm/Support/Casting.h>
42 
43 #include <vector>
44 
45 class ClazyContext;
46 
47 using namespace clang;
48 using namespace std;
49 
50 
51 enum Aggressiveness
52 {
53     NormalAggressiveness = 0,
54     AlsoCheckFunctionCallsAggressiveness = 1 // too many false positives
55 };
56 
AssertWithSideEffects(const std::string & name,ClazyContext * context)57 AssertWithSideEffects::AssertWithSideEffects(const std::string &name, ClazyContext *context)
58     : CheckBase(name, context, Option_CanIgnoreIncludes)
59     , m_aggressiveness(NormalAggressiveness)
60 {
61 }
62 
functionIsOk(StringRef name)63 static bool functionIsOk(StringRef name)
64 {
65     static const vector<StringRef> whitelist = {"qFuzzyIsNull", "qt_noop", "qt_assert", "qIsFinite", "qIsInf",
66                                                 "qIsNaN", "qIsNumericType", "operator==", "operator<", "operator>", "operator<=", "operator>=", "operator!=", "operator+", "operator-"
67                                                 "q_func", "d_func", "isEmptyHelper"
68                                                 "qCross", "qMin", "qMax", "qBound", "priv", "qobject_cast", "dbusService"};
69     return clazy::contains(whitelist, name);
70 }
71 
methodIsOK(const string & name)72 static bool methodIsOK(const string &name)
73 {
74     static const vector<string> whitelist = {"QList::begin", "QList::end", "QVector::begin",
75                                              "QVector::end", "QHash::begin", "QHash::end",
76                                              "QByteArray::data", "QBasicMutex::isRecursive",
77                                              "QLinkedList::begin", "QLinkedList::end", "QDataBuffer::first",
78                                              "QOpenGLFunctions::glIsRenderbuffer"};
79     return clazy::contains(whitelist, name);
80 }
81 
VisitStmt(Stmt * stm)82 void AssertWithSideEffects::VisitStmt(Stmt *stm)
83 {
84     const SourceLocation stmStart = clazy::getLocStart(stm);
85     if (!clazy::isInMacro(&m_astContext, stmStart, "Q_ASSERT"))
86         return;
87 
88     bool warn = false;
89     const bool checkfunctions = m_aggressiveness & AlsoCheckFunctionCallsAggressiveness;
90 
91     auto memberCall = dyn_cast<CXXMemberCallExpr>(stm);
92     if (memberCall) {
93         if (checkfunctions) {
94             CXXMethodDecl *method = memberCall->getMethodDecl();
95             if (!method->isConst() && !methodIsOK(clazy::qualifiedMethodName(method)) && !functionIsOk(clazy::name(method))) {
96                 // llvm::errs() << "reason1 " << clazy::qualifiedMethodName(method) << "\n";
97                 warn = true;
98             }
99         }
100     } else if (auto call = dyn_cast<CallExpr>(stm)) {
101         // Non member function calls not allowed
102 
103         FunctionDecl *func = call->getDirectCallee();
104         if (func && checkfunctions) {
105 
106             if (isa<CXXMethodDecl>(func)) // This will be visited next, so ignore it now
107                 return;
108 
109             if (functionIsOk(clazy::name(func))) {
110                 return;
111             }
112 
113             warn = true;
114         }
115     } else if (auto op = dyn_cast<BinaryOperator>(stm)) {
116         if (op->isAssignmentOp()) {
117             if (DeclRefExpr *declRef = dyn_cast<DeclRefExpr>(op->getLHS())) {
118                 ValueDecl *valueDecl = declRef->getDecl();
119                 if (valueDecl && sm().isBeforeInSLocAddrSpace(clazy::getLocStart(valueDecl), stmStart)) {
120                     // llvm::errs() << "reason3\n";
121                     warn = true;
122                 }
123             }
124         }
125     } else if (auto op = dyn_cast<UnaryOperator>(stm)) {
126         if (auto declRef = dyn_cast<DeclRefExpr>(op->getSubExpr())) {
127             ValueDecl *valueDecl = declRef->getDecl();
128             auto type = op->getOpcode();
129             if (type != UnaryOperatorKind::UO_Deref && type != UnaryOperatorKind::UO_AddrOf) {
130                 if (valueDecl && sm().isBeforeInSLocAddrSpace(clazy::getLocStart(valueDecl), stmStart)) {
131                     // llvm::errs() << "reason5 " << op->getOpcodeStr() << "\n";
132                     warn = true;
133                 }
134             }
135         }
136     }
137 
138     if (warn) {
139         emitWarning(stmStart, "Code inside Q_ASSERT has side-effects but won't be built in release mode");
140     }
141 }
142