Correct Zero/Null as pointer constant (cppcheck-opensource#1938)

scottfurry · danmar · commit a19547747004 · 2019-06-30T21:39:22.000+02:00
Building with enhanced clang warnings indicated a large number of
instances with the warning:

`warning: zero as null pointer constant`

Recommended practice in C++11 is to use `nullptr` as value for
a NULL or empty pointer value. All instances where this warning
was encountered were corrected in this commit.

Where warning was encountered in dependency code (i.e. external library)
no chnages were made. Patching will be offered upstream.
diff --git a/cli/cppcheckexecutor.cpp b/cli/cppcheckexecutor.cpp
@@ -227,7 +227,7 @@ static void print_stacktrace(FILE* output, bool demangling, int maxdepth, bool l
 // 32 vs. 64bit
 #define ADDRESSDISPLAYLENGTH ((sizeof(long)==8)?12:8)
     const int fd = fileno(output);
-    void *callstackArray[32]= {0}; // the less resources the better...
+    void *callstackArray[32]= {nullptr}; // the less resources the better...
     const int currentdepth = backtrace(callstackArray, (int)GetArrayLength(callstackArray));
     const int offset=2; // some entries on top are within our own exception handling code or libc
     if (maxdepth<0)
diff --git a/gui/aboutdialog.h b/gui/aboutdialog.h
@@ -35,8 +35,9 @@ class QWidget;
 class AboutDialog : public QDialog {
     Q_OBJECT
 public:
-    AboutDialog(const QString &version, const QString &extraVersion,
-                QWidget *parent = 0);
+    AboutDialog(const QString &version,
+                const QString &extraVersion,
+                QWidget *parent = nullptr);
 
 private:
     Ui::About mUI;
diff --git a/gui/applicationdialog.h b/gui/applicationdialog.h
@@ -45,8 +45,9 @@ class ApplicationDialog : public QDialog {
     * @param app Application definition.
     * @param parent Parent widget.
     */
-    ApplicationDialog(const QString &title, Application &app,
-                      QWidget *parent = 0);
+    ApplicationDialog(const QString &title,
+                      Application &app,
+                      QWidget *parent = nullptr);
     virtual ~ApplicationDialog();
 
 protected slots:
diff --git a/gui/applicationlist.h b/gui/applicationlist.h
@@ -33,7 +33,7 @@ class ApplicationList : public QObject {
     Q_OBJECT
 public:
 
-    explicit ApplicationList(QObject *parent = 0);
+    explicit ApplicationList(QObject *parent = nullptr);
     virtual ~ApplicationList();
 
     /**
diff --git a/gui/checkstatistics.h b/gui/checkstatistics.h
@@ -30,7 +30,7 @@
  */
 class CheckStatistics : public QObject {
 public:
-    explicit CheckStatistics(QObject *parent = NULL);
+    explicit CheckStatistics(QObject *parent = nullptr);
 
     /**
     * @brief Add new checked item to statistics.
diff --git a/gui/fileviewdialog.h b/gui/fileviewdialog.h
@@ -41,7 +41,7 @@ class FileViewDialog : public QDialog {
 public:
     FileViewDialog(const QString &file,
                    const QString &title,
-                   QWidget *parent = 0);
+                   QWidget *parent = nullptr);
 
 
 protected:
diff --git a/gui/libraryaddfunctiondialog.h b/gui/libraryaddfunctiondialog.h
@@ -15,7 +15,7 @@ class LibraryAddFunctionDialog : public QDialog {
     Q_OBJECT
 
 public:
-    explicit LibraryAddFunctionDialog(QWidget *parent = 0);
+    explicit LibraryAddFunctionDialog(QWidget *parent = nullptr);
     LibraryAddFunctionDialog(const LibraryAddFunctionDialog &) = delete;
     ~LibraryAddFunctionDialog();
     LibraryAddFunctionDialog &operator=(const LibraryAddFunctionDialog &) = delete;
diff --git a/gui/librarydialog.h b/gui/librarydialog.h
@@ -34,7 +34,7 @@ class LibraryDialog : public QDialog {
     Q_OBJECT
 
 public:
-    explicit LibraryDialog(QWidget *parent = 0);
+    explicit LibraryDialog(QWidget *parent = nullptr);
     LibraryDialog(const LibraryDialog &) = delete;
     ~LibraryDialog();
     LibraryDialog &operator=(const LibraryDialog &) = delete;
diff --git a/gui/newsuppressiondialog.h b/gui/newsuppressiondialog.h
@@ -12,7 +12,7 @@ class NewSuppressionDialog : public QDialog {
     Q_OBJECT
 
 public:
-    explicit NewSuppressionDialog(QWidget *parent = 0);
+    explicit NewSuppressionDialog(QWidget *parent = nullptr);
     NewSuppressionDialog(const NewSuppressionDialog &) = delete;
     ~NewSuppressionDialog();
     NewSuppressionDialog &operator=(const NewSuppressionDialog &) = delete;
diff --git a/gui/platforms.h b/gui/platforms.h
@@ -44,7 +44,7 @@ class Platforms : public QObject {
     Q_OBJECT
 
 public:
-    explicit Platforms(QObject *parent = NULL);
+    explicit Platforms(QObject *parent = nullptr);
     void add(const QString &title, Settings::PlatformType platform);
     int getCount() const;
     void init();
diff --git a/gui/projectfile.h b/gui/projectfile.h
@@ -39,8 +39,8 @@ class ProjectFile : public QObject {
     Q_OBJECT
 
 public:
-    explicit ProjectFile(QObject *parent = 0);
-    explicit ProjectFile(const QString &filename, QObject *parent = 0);
+    explicit ProjectFile(QObject *parent = nullptr);
+    explicit ProjectFile(const QString &filename, QObject *parent = nullptr);
 
     /**
      * @brief Read the project file.
diff --git a/gui/projectfiledialog.h b/gui/projectfiledialog.h
@@ -42,7 +42,7 @@ class ProjectFile;
 class ProjectFileDialog : public QDialog {
     Q_OBJECT
 public:
-    explicit ProjectFileDialog(ProjectFile *projectFile, QWidget *parent = 0);
+    explicit ProjectFileDialog(ProjectFile *projectFile, QWidget *parent = nullptr);
     virtual ~ProjectFileDialog();
 
 private:
diff --git a/gui/resultstree.cpp b/gui/resultstree.cpp
@@ -56,13 +56,13 @@ ResultsTree::ResultsTree(QWidget * parent) :
     QTreeView(parent),
     mSettings(nullptr),
     mApplications(nullptr),
-    mContextItem(0),
+    mContextItem(nullptr),
     mShowFullPath(false),
     mSaveFullPath(false),
     mSaveAllErrors(true),
     mShowErrorId(false),
     mVisibleErrors(false),
-    mSelectionModel(0),
+    mSelectionModel(nullptr),
     mThread(nullptr),
     mShowCppcheck(true),
     mShowClang(true)
@@ -330,7 +330,7 @@ QStandardItem *ResultsTree::findFileItem(const QString &name) const
 #endif
             return mModel.item(i, 0);
     }
-    return 0;
+    return nullptr;
 }
 
 void ResultsTree::clear()
diff --git a/gui/resultstree.h b/gui/resultstree.h
@@ -48,7 +48,7 @@ class ThreadHandler;
 class ResultsTree : public QTreeView {
     Q_OBJECT
 public:
-    explicit ResultsTree(QWidget * parent = 0);
+    explicit ResultsTree(QWidget * parent = nullptr);
     virtual ~ResultsTree();
     void initialize(QSettings *settings, ApplicationList *list, ThreadHandler *checkThreadHandler);
 
diff --git a/gui/resultsview.cpp b/gui/resultsview.cpp
@@ -161,7 +161,7 @@ void ResultsView::save(const QString &filename, Report::Type type) const
         msgBox.exec();
     }
 
-    Report *report = NULL;
+    Report *report = nullptr;
 
     switch (type) {
     case Report::CSV:
@@ -185,7 +185,7 @@ void ResultsView::save(const QString &filename, Report::Type type) const
             msgBox.exec();
         }
         delete report;
-        report = NULL;
+        report = nullptr;
     } else {
         QMessageBox msgBox;
         msgBox.setText(tr("Failed to save the report."));
diff --git a/gui/resultsview.h b/gui/resultsview.h
@@ -44,7 +44,7 @@ class ResultsView : public QWidget {
     Q_OBJECT
 public:
 
-    explicit ResultsView(QWidget * parent = 0);
+    explicit ResultsView(QWidget * parent = nullptr);
     void initialize(QSettings *settings, ApplicationList *list, ThreadHandler *checkThreadHandler);
     ResultsView(const ResultsView &) = delete;
     virtual ~ResultsView();
diff --git a/gui/settingsdialog.cpp b/gui/settingsdialog.cpp
@@ -226,7 +226,7 @@ void SettingsDialog::removeApplication()
 void SettingsDialog::editApplication()
 {
     QList<QListWidgetItem *> selected = mUI.mListWidget->selectedItems();
-    QListWidgetItem *item = 0;
+    QListWidgetItem *item = nullptr;
     foreach (item, selected) {
         int row = mUI.mListWidget->row(item);
         Application& app = mTempApplications->getApplication(row);
diff --git a/gui/settingsdialog.h b/gui/settingsdialog.h
@@ -41,7 +41,7 @@ class SettingsDialog : public QDialog {
 public:
     SettingsDialog(ApplicationList *list,
                    TranslationHandler *translator,
-                   QWidget *parent = 0);
+                   QWidget *parent = nullptr);
     SettingsDialog(const SettingsDialog &) = delete;
     virtual ~SettingsDialog();
     SettingsDialog &operator=(const SettingsDialog &) = delete;
diff --git a/gui/statsdialog.cpp b/gui/statsdialog.cpp
@@ -149,7 +149,7 @@ void StatsDialog::pdfExport()
                          .arg(tr("Information messages"))
                          .arg(mStatistics->getCount(CPPCHECK,ShowTypes::ShowInformation));
 
-    QString fileName = QFileDialog::getSaveFileName((QWidget*)0, tr("Export PDF"), QString(), "*.pdf");
+    QString fileName = QFileDialog::getSaveFileName((QWidget*)nullptr, tr("Export PDF"), QString(), "*.pdf");
     if (QFileInfo(fileName).suffix().isEmpty()) {
         fileName.append(".pdf");
     }
diff --git a/gui/statsdialog.h b/gui/statsdialog.h
@@ -38,7 +38,7 @@ class CheckStatistics;
 class StatsDialog : public QDialog {
     Q_OBJECT
 public:
-    explicit StatsDialog(QWidget *parent = 0);
+    explicit StatsDialog(QWidget *parent = nullptr);
 
     /**
     * @brief Sets the project to extract statistics from
diff --git a/gui/threadhandler.h b/gui/threadhandler.h
@@ -44,7 +44,7 @@ class Settings;
 class ThreadHandler : public QObject {
     Q_OBJECT
 public:
-    explicit ThreadHandler(QObject *parent = 0);
+    explicit ThreadHandler(QObject *parent = nullptr);
     virtual ~ThreadHandler();
 
     /**
diff --git a/gui/translationhandler.cpp b/gui/translationhandler.cpp
@@ -47,7 +47,7 @@ static void unused()
 TranslationHandler::TranslationHandler(QObject *parent) :
     QObject(parent),
     mCurrentLanguage("en"),
-    mTranslator(NULL)
+    mTranslator(nullptr)
 {
     // Add our available languages
     // Keep this list sorted
@@ -90,7 +90,7 @@ bool TranslationHandler::setLanguage(const QString &code)
         if (mTranslator) {
             qApp->removeTranslator(mTranslator);
             delete mTranslator;
-            mTranslator = NULL;
+            mTranslator = nullptr;
         }
 
         mCurrentLanguage = code;
diff --git a/gui/translationhandler.h b/gui/translationhandler.h
@@ -61,7 +61,7 @@ struct TranslationInfo {
 class TranslationHandler : QObject {
     Q_OBJECT
 public:
-    explicit TranslationHandler(QObject *parent = 0);
+    explicit TranslationHandler(QObject *parent = nullptr);
     virtual ~TranslationHandler();
 
     /**
diff --git a/gui/xmlreportv2.cpp b/gui/xmlreportv2.cpp
@@ -50,8 +50,8 @@ static const QString VerboseAttribute = "verbose";
 
 XmlReportV2::XmlReportV2(const QString &filename) :
     XmlReport(filename),
-    mXmlReader(NULL),
-    mXmlWriter(NULL)
+    mXmlReader(nullptr),
+    mXmlWriter(nullptr)
 {
 }
 
diff --git a/lib/ctu.cpp b/lib/ctu.cpp
@@ -522,7 +522,7 @@ std::list<ErrorLogger::ErrorMessage::FileLocation> CTU::FileInfo::getErrorPath(I
 {
     std::list<ErrorLogger::ErrorMessage::FileLocation> locationList;
 
-    const CTU::FileInfo::CallBase *path[10] = {0};
+    const CTU::FileInfo::CallBase *path[10] = {nullptr};
 
     if (!findPath(unsafeUsage.myId, unsafeUsage.myArgNr, unsafeUsage.value, invalidValue, callsMap, path, 0, warning))
         return locationList;
diff --git a/lib/mathlib.cpp b/lib/mathlib.cpp
@@ -370,7 +370,7 @@ MathLib::bigint MathLib::characterLiteralToLongNumber(const std::string& str)
 
     // '\123'
     if (str.size() == 4 && str[0] == '\\' && isoctal(str[1]) && isoctal(str[2]) && isoctal(str[3])) {
-        return (char)std::strtoul(str.substr(1).c_str(), NULL, 8);
+        return (char)std::strtoul(str.substr(1).c_str(), nullptr, 8);
     }
 
     // C99 6.4.4.4
diff --git a/lib/symboldatabase.cpp b/lib/symboldatabase.cpp
@@ -967,7 +967,7 @@ void SymbolDatabase::createSymbolDatabaseVariableSymbolTable()
                 (tok->next()->str() == "." ||
                  (tok->next()->str() == "[" && tok->linkAt(1)->strAt(1) == "."))) {
                 const Token *tok1 = tok->next()->str() == "." ? tok->tokAt(2) : tok->linkAt(1)->tokAt(2);
-                if (tok1 && tok1->varId() && mVariableList[tok1->varId()] == 0) {
+                if (tok1 && tok1->varId() && mVariableList[tok1->varId()] == nullptr) {
                     const Variable *var = mVariableList[tok->varId()];
                     if (var && var->typeScope()) {
                         // find the member variable of this variable
diff --git a/lib/valueflow.cpp b/lib/valueflow.cpp
@@ -3579,7 +3579,7 @@ static void valueFlowForwardAssign(Token * const               tok,
             if (it->isIntValue())
                 it->intvalue = (it->intvalue != 0);
             if (it->isTokValue())
-                it ->intvalue = (it->tokvalue != 0);
+                it ->intvalue = (it->tokvalue != nullptr);
         }
     }
 
@@ -5437,9 +5437,9 @@ void ValueFlow::setValues(TokenList *tokenlist, SymbolDatabase* symboldatabase,
     valueFlowFwdAnalysis(tokenlist, settings);
 
     // Temporary hack.. run valueflow until there is nothing to update or timeout expires
-    const std::time_t timeout = std::time(0) + TIMEOUT;
+    const std::time_t timeout = std::time(nullptr) + TIMEOUT;
     std::size_t values = 0;
-    while (std::time(0) < timeout && values < getTotalValues(tokenlist)) {
+    while (std::time(nullptr) < timeout && values < getTotalValues(tokenlist)) {
         values = getTotalValues(tokenlist);
         valueFlowArrayBool(tokenlist);
         valueFlowRightShift(tokenlist, settings);
diff --git a/test/testbufferoverrun.cpp b/test/testbufferoverrun.cpp
@@ -3918,7 +3918,7 @@ class TestBufferOverrun : public TestFixture {
     void getErrorMessages() {
         // Ticket #2292: segmentation fault when using --errorlist
         CheckBufferOverrun c;
-        c.getErrorMessages(this, 0);
+        c.getErrorMessages(this, nullptr);
     }
 
     void arrayIndexThenCheck() {
diff --git a/test/testclass.cpp b/test/testclass.cpp
@@ -3320,7 +3320,7 @@ class TestClass : public TestFixture {
                       "[test.cpp:3]: (warning) Suspicious pointer subtraction. Did you intend to write '->'?\n", errout.str());
     }
 
-    void checkConst(const char code[], Settings *s = 0, bool inconclusive = true) {
+    void checkConst(const char code[], Settings *s = nullptr, bool inconclusive = true) {
         // Clear the error log
         errout.str("");
 
@@ -5552,7 +5552,7 @@ class TestClass : public TestFixture {
                    "  void set(const Key& key) {\n"
                    "      inherited::set(inherited::Key(key));\n"
                    "  }\n"
-                   "};\n", 0, false);
+                   "};\n", nullptr, false);
         ASSERT_EQUALS("", errout.str());
     }
 
@@ -6774,7 +6774,7 @@ class TestClass : public TestFixture {
         ASSERT_EQUALS("", errout.str());
     }
 
-    void checkVirtualFunctionCall(const char code[], Settings *s = 0, bool inconclusive = true) {
+    void checkVirtualFunctionCall(const char code[], Settings *s = nullptr, bool inconclusive = true) {
         // Clear the error log
         errout.str("");
 
diff --git a/test/testgarbage.cpp b/test/testgarbage.cpp
@@ -281,7 +281,7 @@ class TestGarbage : public TestFixture {
 
         tokenizer.simplifyTokenList2();
 
-        return tokenizer.tokens()->stringifyList(false, false, false, true, false, 0, 0);
+        return tokenizer.tokens()->stringifyList(false, false, false, true, false, nullptr, nullptr);
     }
 
     std::string getSyntaxError(const char code[]) {
diff --git a/test/testmemleak.cpp b/test/testmemleak.cpp
@@ -110,7 +110,7 @@ class TestMemleak : private TestFixture {
 
         // there is no allocation
         const Token *tok = Token::findsimplematch(tokenizer.tokens(), "ret =");
-        const CheckMemoryLeak check(&tokenizer, 0, &settings);
+        const CheckMemoryLeak check(&tokenizer, nullptr, &settings);
         ASSERT_EQUALS(CheckMemoryLeak::No, check.getAllocationType(tok->tokAt(2), 1));
     }
 };
diff --git a/test/testother.cpp b/test/testother.cpp
@@ -1875,7 +1875,7 @@ class TestOther : public TestFixture {
               "    case 3:\n"
               "      strcpy(str, \"b'\");\n"
               "    }\n"
-              "}", 0, false, false, false);
+              "}", nullptr, false, false, false);
         // TODO ASSERT_EQUALS("[test.cpp:6] -> [test.cpp:8]: (warning) Buffer 'str' is being written before its old content has been used. 'break;' missing?\n", errout.str());
 
         check("void foo(int a) {\n"
@@ -3346,7 +3346,7 @@ class TestOther : public TestFixture {
 
         check("void f(char c) {\n"
               "    printf(\"%i\", 1 + 1 ? 1 : 2);\n" // "1+1" is simplified away
-              "}",0,false,false,false);
+              "}",nullptr,false,false,false);
         ASSERT_EQUALS("[test.cpp:2]: (style) Clarify calculation precedence for '+' and '?'.\n", errout.str());
 
         check("void f() {\n"
diff --git a/test/testpreprocessor.cpp b/test/testpreprocessor.cpp
@@ -46,7 +46,7 @@ class TestPreprocessor : public TestFixture {
     class OurPreprocessor : public Preprocessor {
     public:
 
-        static std::string expandMacros(const char code[], ErrorLogger *errorLogger = 0) {
+        static std::string expandMacros(const char code[], ErrorLogger *errorLogger = nullptr) {
             std::istringstream istr(code);
             simplecpp::OutputList outputList;
             std::vector<std::string> files;
@@ -269,7 +269,7 @@ class TestPreprocessor : public TestFixture {
         }
     }
 
-    std::string getConfigsStr(const char filedata[], const char *arg=NULL) {
+    std::string getConfigsStr(const char filedata[], const char *arg = nullptr) {
         Settings settings;
         if (arg && std::strncmp(arg,"-D",2)==0)
             settings.userDefines = arg + 2;
diff --git a/test/testsimplifytemplate.cpp b/test/testsimplifytemplate.cpp
diff --git a/test/testsimplifytokens.cpp b/test/testsimplifytokens.cpp
diff --git a/test/testsimplifytypedef.cpp b/test/testsimplifytypedef.cpp
diff --git a/test/testsimplifyusing.cpp b/test/testsimplifyusing.cpp
diff --git a/test/testsymboldatabase.cpp b/test/testsymboldatabase.cpp
diff --git a/test/testtoken.cpp b/test/testtoken.cpp
diff --git a/test/testtokenize.cpp b/test/testtokenize.cpp
diff --git a/test/testtype.cpp b/test/testtype.cpp
diff --git a/test/testutils.h b/test/testutils.h
