Each file in this commit exhibit an example of what prevent calls

'reverse inull'. All that means is that a pointer gets dereferenced. Then
a pointer gets checked for validity before being dereferenced again. This
almost always points to shenanigans.

For example, the konsole.cpp file has this konsoleInit() call which passes
in a const char** shell variable. Since it is a double pointer the programmer
who wrote the code made the mistake of mixing the checking of the pointer
and the pointer that points to the pointer. This commit attempts to correct
that.

Of course there are other instances of the same thing. But they all boil
down to a small mistake which might have produced strange side effects.

4 files changed, 49 insertions, 65 deletions

diff --git a/core/apps/embeddedkonsole/konsole.cpp b/core/apps/embeddedkonsole/konsole.cpp
index f4ca0bf..5c40569 100644
--- a/core/apps/embeddedkonsole/konsole.cpp
+++ b/core/apps/embeddedkonsole/konsole.cpp
@@ -188,68 +188,74 @@ static const char *commonCmds[] =
             "hostname",
             "kill",
             "killall",
             "ln",
             "ping",
             "mount",
             "more",
             "sort",
             "touch",
             "umount",
             "mknod",
             "netstat",
         */
 
         "exit",
         NULL
     };
 
 
 static void konsoleInit(const char** shell) {
     if(setuid(getuid()) !=0) odebug << "setuid failed" << oendl;
     if(setgid(getgid()) != 0) odebug << "setgid failed" << oendl;  // drop privileges
 
 
 //  QPEApplication::grabKeyboard(); // for CTRL and ALT
 
     odebug << "keyboard grabbed" << oendl;
 #ifdef FAKE_CTRL_AND_ALT
     odebug << "Fake Ctrl and Alt defined" << oendl;
     QPEApplication::grabKeyboard(); // for CTRL and ALT
 #endif
 
+    if (!shell) {
+        owarn << "No double pointer 'shell'" << oendl;
+        return;
+    }
+
     *shell = getenv("SHELL");
-    owarn << "SHell initially is " << *shell << "" << oendl;
+    if (*shell)
+        owarn << "Current shell: " << *shell << "" << oendl;
 
-    if (shell == NULL || *shell == '\0') {
+    if (*shell == NULL || **shell == '\0') {
         struct passwd *ent = 0;
         uid_t me = getuid();
         *shell = "/bin/sh";
 
         while ( (ent = getpwent()) != 0 ) {
             if (ent->pw_uid == me) {
                 if (ent->pw_shell != "")
                     *shell = ent->pw_shell;
                 break;
             }
         }
         endpwent();
     }
 
     if( putenv((char*)"COLORTERM=") !=0)
         odebug << "putenv failed" << oendl;  // to trigger mc's color detection
 }
 
 
 Konsole::Konsole(QWidget* parent, const char* name, WFlags fl) :
         QMainWindow(parent, name, fl)
 {
     QStrList tmp; const char* shell;
 
     konsoleInit( &shell);
     init(shell,tmp);
 }
 
 Konsole::Konsole(const char* name, const char* _pgm, QStrList & _args, int)
         : QMainWindow(0, name)
 {
     init(_pgm,_args);
diff --git a/core/apps/textedit/textedit.cpp b/core/apps/textedit/textedit.cpp
index 61beac5..4bbc62b 100644
--- a/core/apps/textedit/textedit.cpp
+++ b/core/apps/textedit/textedit.cpp
@@ -821,164 +821,144 @@ bool TextEdit::save() {
                 odebug << "regular save file" << oendl;
                 QFile f(file);
                                                                 if( f.open(IO_WriteOnly)) {
                                                                                 QCString crt = rt.utf8();
                                                                                 f.writeBlock(crt,crt.length());
                                                                 } else {
                                                                                 QMessageBox::message(tr("Text Edit"),tr("Write Failed"));
                                                                                 return false;
                                                                 }
 
             }
             editor->setEdited( false);
             edited1=false;
             edited=false;
             if(caption().left(1)=="*")
                                                                 setCaption(caption().right(caption().length()-1));
 
 
             chmod( file.latin1(), mode);
         }
         return true;
     }
     return false;
 }
 
 /*!
   prompted save */
 bool TextEdit::saveAs() {
 
     if(caption() == tr("Text Editor"))
         return false;
     odebug << "saveAsFile " + currentFileName << oendl;
-      // case of nothing to save...
-//     if ( !doc && !currentFileName.isEmpty()) {
-// //|| !bFromDocView)
-//         odebug << "no doc" << oendl;
-//         return true;
-//     }
-//     if ( !editor->edited() ) {
-//         delete doc;
-//         doc = 0;
-//         return true;
-//     }
 
     QString rt = editor->text();
     odebug << currentFileName << oendl;
 
     if( currentFileName.isEmpty()
         || currentFileName == tr("Unnamed")
-        || currentFileName == tr("Text Editor")) {
+        || currentFileName == tr("Text Editor"))
+    {
         odebug << "do silly TT filename thing" << oendl;
-//        if ( doc && doc->name().isEmpty() ) {
         QString pt = rt.simplifyWhiteSpace();
         int i = pt.find( ' ' );
         QString docname = pt;
-        if ( i > 0 )
-            docname = pt.left( i );
-          // remove "." at the beginning
+        if ( i > 0 ) docname = pt.left( i );
+
         while( docname.startsWith( "." ) )
             docname = docname.mid( 1 );
         docname.replace( QRegExp("/"), "_" );
-          // cut the length. filenames longer than that
-          //don't make sense and something goes wrong when they get too long.
-        if ( docname.length() > 40 )
-            docname = docname.left(40);
-        if ( docname.isEmpty() )
-            docname = tr("Unnamed");
+        // Cut the length. Filenames longer than 40 are not helpful
+        // and something goes wrong when they get too long.
+        if ( docname.length() > 40 ) docname = docname.left(40);
+
+        if ( docname.isEmpty() ) docname = tr("Unnamed");
+
         if(doc) doc->setName(docname);
+
         currentFileName=docname;
-//         }
-//         else
-//             odebug << "hmmmmmm" << oendl;
     }
 
 
     QMap<QString, QStringList> map;
     map.insert(tr("All"), QStringList() );
     QStringList text;
     text << "text/*";
     map.insert(tr("Text"), text );
     text << "*";
     map.insert(tr("All"), text );
 
     QFileInfo cuFi( currentFileName);
     QString filee = cuFi.fileName();
     QString dire = cuFi.dirPath();
     if(dire==".")
         dire = QPEApplication::documentDir();
+
     QString str;
     if( !featureAutoSave) {
-                                str = OFileDialog::getSaveFileName( 2,
-                                                                                                                                                                                dire,
-                                                                                                                                                                                filee, map);
-                } else
+        str = OFileDialog::getSaveFileName( 2, dire, filee, map);
+    } else
         str = currentFileName;
 
     if(!str.isEmpty()) {
         QString fileNm=str;
 
         odebug << "saving filename "+fileNm << oendl;
         QFileInfo fi(fileNm);
         currentFileName=fi.fileName();
         if(doc)
-//        QString file = doc->file();
-//        doc->removeFiles();
             delete doc;
-                                DocLnk nf;
-                                nf.setType("text/plain");
-                                nf.setFile( fileNm);
-                                doc = new DocLnk(nf);
-//        editor->setText(rt);
-                                odebug << "Saving file as "+currentFileName << oendl;
-                                doc->setName( fi.baseName() /*currentFileName*/);
-                                updateCaption( currentFileName);
-
-                                FileManager fm;
-                                if ( !fm.saveFile( *doc, rt ) ) {
-                                                QMessageBox::message(tr("Text Edit"),tr("Save Failed"));
-                                                return false;
-                                }
-
-                                if( filePerms ) {
-                                                filePermissions *filePerm;
-                                                filePerm = new filePermissions(this,
-                                                                                                                                                                         tr("Permissions"),true,
-                                                                                                                                                                         0,(const QString &)fileNm);
-                                                QPEApplication::execDialog( filePerm );
-
-                                                if( filePerm)
-                                                                delete  filePerm;
-                                }
-//        }
+
+        DocLnk nf;
+        nf.setType("text/plain");
+        nf.setFile( fileNm);
+        doc = new DocLnk(nf);
+        odebug << "Saving file as "+currentFileName << oendl;
+        doc->setName( fi.baseName() );
+        updateCaption( currentFileName);
+
+        FileManager fm;
+        if ( !fm.saveFile( *doc, rt ) ) {
+            QMessageBox::message(tr("Text Edit"),tr("Save Failed"));
+            return false;
+        }
+
+        if( filePerms ) {
+            filePermissions *filePerm;
+            filePerm = new filePermissions(this, tr("Permissions"),true, 0,
+                                           (const QString &)fileNm);
+            QPEApplication::execDialog( filePerm );
+
+            delete  filePerm;
+        }
         editor->setEdited( false);
         edited1 = false;
         edited = false;
         if(caption().left(1)=="*")
             setCaption(caption().right(caption().length()-1));
 
         return true;
     }
     odebug << "returning false" << oendl;
     currentFileName = "";
     return false;
 } //end saveAs
 
 void TextEdit::clear() {
     delete doc;
     doc = 0;
     editor->clear();
 }
 
 void TextEdit::updateCaption( const QString &name ) {
 
     if ( name.isEmpty() )
         setCaption( tr("Text Editor") );
     else {
         QString s = name;
         if ( s.isNull() )
             s = doc->name();
         if ( s.isEmpty()  ) {
             s = tr( "Unnamed" );
             currentFileName=s;
         }
 //         if(s.left(1) == "/")
@@ -1168,46 +1148,44 @@ void TextEdit::doTimer(bool b)
       }
 //     else
 //         odebug << "doTimer false" << oendl;
 }
 
 void TextEdit::setTimer()
 {
 if(featureAutoSave)
   {
 //      odebug << "setting autosave" << oendl;
       QTimer *timer = new QTimer(this );
       connect( timer, SIGNAL(timeout()), this, SLOT(timerCrank()) );
       timer->start( 300000, true); //5 minutes
     }
 }
 
 void TextEdit::gotoLine() {
     if( editor->length() < 1)
        return;
    QWidget *d = QApplication::desktop();
    gotoEdit = new QLineEdit( 0, "Goto line");
 
    gotoEdit->move( (d->width()/2) - ( gotoEdit->width()/2) , (d->height()/2) - (gotoEdit->height()/2));
    gotoEdit->setFrame(true);
    gotoEdit->show();
    connect (gotoEdit,SIGNAL(returnPressed()), this, SLOT(doGoto()));
 }
 
 void TextEdit::doGoto() {
    QString number = gotoEdit->text();
    gotoEdit->hide();
 
-   if(gotoEdit) {
-      delete gotoEdit;
-      gotoEdit = 0;
-   }
+   delete gotoEdit;
+   gotoEdit = 0;
 
    bool ok;
    int lineNumber = number.toInt(&ok, 10);
    if( editor->numLines() < lineNumber)
       QMessageBox::message(tr("Text Edit"),tr("Not enough lines"));
    else
    {
       editor->setCursorPosition(lineNumber, 0, false);
    }
 }
diff --git a/noncore/applets/notesapplet/notes.cpp b/noncore/applets/notesapplet/notes.cpp
index 13f297e..61a47d7 100644
--- a/noncore/applets/notesapplet/notes.cpp
+++ b/noncore/applets/notesapplet/notes.cpp
@@ -206,65 +206,65 @@ void NotesControl::slotBeamFinished(Ir *) {
 
 void NotesControl::boxPressed(int mouse, QListBoxItem *, const QPoint&) {
   switch (mouse) {
     case 1:{
     }
     break;
   case 2:
     menuTimer.start( 500, TRUE );
     break;
   };
 }
 
 void NotesControl::slotBoxSelected(const QString &itemString) {
     if(edited) {
         save();
     }
     loaded=false;
     edited=false;
     load(itemString);
 }
 
 
 void NotesControl::showMenu() {
   QPopupMenu *m = new QPopupMenu(0);
   m->insertItem(  tr( "Beam Out" ), this,  SLOT( slotBeamButton() ));
   m->insertItem(  tr( "Search For..." ), this,  SLOT( slotSearch() ));
   m->insertItem(  tr( "Toggle Maximized" ), this,  SLOT( slotShowMax() ));
   m->insertSeparator();
   m->insertItem(  tr( "Delete" ), this,  SLOT( slotDeleteButton() ));
   m->setFocus();
   m->exec( QCursor::pos() );
 
-  if(m) delete m;
+  delete m;
 }
 
 void NotesControl::focusOutEvent ( QFocusEvent * e) {
     if( e->reason() == QFocusEvent::Popup)
         save();
     else {
         if(!loaded) {
         populateBox();
         load();
         }
     }
     QWidget::focusOutEvent(e);
 }
 
 void NotesControl::save() {
     Config cfg("Notes");
     cfg.setGroup("Docs");
     if( edited) {
 //        odebug << "is edited" << oendl;
         QString rt = view->text();
         if( rt.length()>1) {
             QString pt = rt.simplifyWhiteSpace();
             int i = pt.find( ' ', pt.find( ' ' )+2 );
             QString docname = pt;
             if ( i > 0 )
                 docname = pt.left(i);
               // remove "." at the beginning
             while( docname.startsWith( "." ) )
                 docname = docname.mid( 1 );
             docname.replace( QRegExp("/"), "_" );
               // cut the length. filenames longer than that don't make sense
               // and something goes wrong when they get too long.
diff --git a/noncore/apps/advancedfm/advancedfm.cpp b/noncore/apps/advancedfm/advancedfm.cpp
index 828f5a1..cf19ba8 100644
--- a/noncore/apps/advancedfm/advancedfm.cpp
+++ b/noncore/apps/advancedfm/advancedfm.cpp
@@ -467,65 +467,65 @@ void AdvancedFm::showFileMenu() {
    n->insertItem(tr("Rename"),this,SLOT(renameIt()));
 
    n->insertItem(tr("Copy"),this,SLOT(copyTimer()));
    n->insertItem(tr("Copy As"),this,SLOT(copyAsTimer()));
    n->insertItem(tr("Copy Same Dir"),this,SLOT(copySameDirTimer()));
    n->insertItem(tr("Move"),this,SLOT(moveTimer()));
 
    n->insertSeparator();
    n->insertItem(tr("Delete"),this,SLOT(doDelete()));
    m->insertItem(tr("Add To Documents"),this,SLOT(addToDocs()));
 
    m->insertItem(tr("Run Command"),this,SLOT(runCommand()));
    m->insertItem(tr("File Info"),this,SLOT(fileStatus()));
 
    m->insertSeparator();
    m->insertItem(tr("Set Permissions"),this,SLOT(filePerms()));
 
 #if defined(QT_QWS_OPIE)
    m->insertItem(tr("Properties"),this,SLOT(doProperties()));
 #endif
    m->setCheckable(TRUE);
    if (!b)
       m->setItemChecked(m->idAt(0),TRUE);
    else
       m->setItemChecked(m->idAt(0),FALSE);
 
    if(Ir::supported())
       m->insertItem(tr("Beam File"),this,SLOT(doBeam()));
    m->setFocus();
 
    m->exec(QPoint(QCursor::pos().x(),QCursor::pos().y()));
 
-   if(m) delete m;
+   delete m;
 }
 
 
 QString AdvancedFm::checkDiskSpace(const QString &path) {
    struct statfs fss;
    if ( !statfs( path.latin1(), &fss ) ) {
       int blkSize = fss.f_bsize;
 //    int totalBlks = fs.f_blocks;
       int availBlks = fss.f_bavail;
 
       long mult = blkSize / 1024;
       long div = 1024 / blkSize;
       if ( !mult ) mult = 1;
       if ( !div ) div = 1;
 
 
       return QString::number(availBlks * mult / div);
    }
    return "";
 }
 
 void AdvancedFm::addToDocs() {
    QStringList strListPaths = getPath();
    QDir *thisDir = CurrentDir();
 
    if( strListPaths.count() > 0) {
       QString curFile;
       for ( QStringList::Iterator it = strListPaths.begin(); it != strListPaths.end(); ++it ) {
          curFile = thisDir->canonicalPath()+"/"+(*it);
 //                odebug << curFile << oendl;
          QFileInfo fi(curFile);
          DocLnk f;