Add some const to make the code easier to follow

src/Character.h

@@ -190,7 +190,7 @@ public:
      * @param unicodePoints An array of unicode character points
      * @param length Length of @p unicodePoints
      */
-    ushort createExtendedChar(ushort* unicodePoints , ushort length);
+    ushort createExtendedChar(const ushort* unicodePoints , ushort length);
     /**
      * Looks up and returns a pointer to a sequence of unicode characters
      * which was added to the table using createExtendedChar().
@@ -207,10 +207,10 @@ public:
     static ExtendedCharTable instance;
 private:
     // calculates the hash key of a sequence of unicode points of size 'length'
-    ushort extendedCharHash(ushort* unicodePoints , ushort length) const;
+    ushort extendedCharHash(const ushort* unicodePoints , ushort length) const;
     // tests whether the entry in the table specified by 'hash' matches the 
     // character sequence 'unicodePoints' of size 'length'
-    bool extendedCharMatch(ushort hash , ushort* unicodePoints , ushort length) const;
+    bool extendedCharMatch(ushort hash , const ushort* unicodePoints , ushort length) const;
     // internal, maps hash keys to character sequence buffers.  The first ushort
     // in each value is the length of the buffer, followed by the ushorts in the buffer
     // themselves.

src/Emulation.cpp

@@ -359,7 +359,7 @@ QSize Emulation::imageSize() const
   return QSize(_currentScreen->getColumns(), _currentScreen->getLines());
 }
 
-ushort ExtendedCharTable::extendedCharHash(ushort* unicodePoints , ushort length) const
+ushort ExtendedCharTable::extendedCharHash(const ushort* unicodePoints , ushort length) const
 {
     ushort hash = 0;
     for ( ushort i = 0 ; i < length ; i++ )
@@ -368,7 +368,7 @@ ushort ExtendedCharTable::extendedCharHash(ushort* unicodePoints , ushort length
     }
     return hash;
 }
-bool ExtendedCharTable::extendedCharMatch(ushort hash , ushort* unicodePoints , ushort length) const
+bool ExtendedCharTable::extendedCharMatch(ushort hash , const ushort* unicodePoints , ushort length) const
 {
     ushort* entry = extendedCharTable[hash];
 
@@ -385,7 +385,7 @@ bool ExtendedCharTable::extendedCharMatch(ushort hash , ushort* unicodePoints ,
     } 
     return true;
 }
-ushort ExtendedCharTable::createExtendedChar(ushort* unicodePoints , ushort length)
+ushort ExtendedCharTable::createExtendedChar(const ushort* unicodePoints , ushort length)
 {
     // look for this sequence of points in the table
     ushort hash = extendedCharHash(unicodePoints,length);

src/SessionManager.cpp

@@ -310,7 +310,7 @@ SessionManager::~SessionManager()
     }
 }
 
-const QList<Session*> SessionManager::sessions()
+const QList<Session*> SessionManager::sessions() const
 {
     return _sessions;
 }

src/SessionManager.h

@@ -178,7 +178,7 @@ public:
     /**
      * Returns a list of active sessions.
      */
-    const QList<Session*> sessions();
+    const QList<Session*> sessions() const;
 
     /**
      * Deletes the configuration file used to store a profile.

src/TerminalDisplay.cpp

@@ -1014,8 +1014,8 @@ void TerminalDisplay::updateImage()
         quint16 c = newLine[x+0].character;
         if ( !c )
             continue;
-        bool lineDraw = isLineChar(c);
-        bool doubleWidth = (x+1 == columnsToUpdate) ? false : (newLine[x+1].character == 0);
+        const bool lineDraw = isLineChar(c);
+        const bool doubleWidth = (x+1 == columnsToUpdate) ? false : (newLine[x+1].character == 0);
         cr = newLine[x].rendition;
         _clipboard = newLine[x].backgroundColor;
         if (newLine[x].foregroundColor != cf) cf = newLine[x].foregroundColor;
@@ -1371,14 +1371,14 @@ void TerminalDisplay::paintFilters(QPainter& painter)
 }
 void TerminalDisplay::drawContents(QPainter &paint, const QRect &rect)
 {
-  QPoint tL  = contentsRect().topLeft();
-  int    tLx = tL.x();
-  int    tLy = tL.y();
+  const QPoint tL  = contentsRect().topLeft();
+  const int    tLx = tL.x();
+  const int    tLy = tL.y();
 
-  int lux = qMin(_usedColumns-1, qMax(0,(rect.left()   - tLx - _leftMargin ) / _fontWidth));
-  int luy = qMin(_usedLines-1,  qMax(0,(rect.top()    - tLy - _topMargin  ) / _fontHeight));
-  int rlx = qMin(_usedColumns-1, qMax(0,(rect.right()  - tLx - _leftMargin ) / _fontWidth));
-  int rly = qMin(_usedLines-1,  qMax(0,(rect.bottom() - tLy - _topMargin  ) / _fontHeight));
+  const int lux = qMin(_usedColumns-1, qMax(0,(rect.left()   - tLx - _leftMargin ) / _fontWidth));
+  const int luy = qMin(_usedLines-1,  qMax(0,(rect.top()    - tLy - _topMargin  ) / _fontHeight));
+  const int rlx = qMin(_usedColumns-1, qMax(0,(rect.right()  - tLx - _leftMargin ) / _fontWidth));
+  const int rly = qMin(_usedLines-1,  qMax(0,(rect.bottom() - tLy - _topMargin  ) / _fontHeight));
 
   const int bufferSize = _usedColumns;
   QString unistr;
@@ -1422,11 +1422,11 @@ void TerminalDisplay::drawContents(QPainter &paint, const QRect &rect)
         }
       }
 
-      bool lineDraw = isLineChar(c);
-      bool doubleWidth = (_image[ qMin(loc(x,y)+1,_imageSize) ].character == 0);
-      CharacterColor currentForeground = _image[loc(x,y)].foregroundColor;
-      CharacterColor currentBackground = _image[loc(x,y)].backgroundColor;
-      quint8 currentRendition = _image[loc(x,y)].rendition;
+      const bool lineDraw = isLineChar(c);
+      const bool doubleWidth = (_image[ qMin(loc(x,y)+1,_imageSize) ].character == 0);
+      const CharacterColor currentForeground = _image[loc(x,y)].foregroundColor;
+      const CharacterColor currentBackground = _image[loc(x,y)].backgroundColor;
+      const quint8 currentRendition = _image[loc(x,y)].rendition;
       
       while (x+len <= rlx &&
              _image[loc(x+len,y)].foregroundColor == currentForeground &&
@@ -2201,7 +2201,7 @@ void TerminalDisplay::mouseDoubleClickEvent(QMouseEvent* ev)
   _wordSelectionMode = true;
 
   // find word boundaries...
-  QChar selClass = charClass(_image[i].character);
+  const QChar selClass = charClass(_image[i].character);
   {
      // find the start of the word
      int x = bgnSel.x();
@@ -2334,7 +2334,7 @@ void TerminalDisplay::mouseTripleClickEvent(QMouseEvent* ev)
   if (_tripleClickMode == SelectForwardsFromCursor) {
     // find word boundary start
     int i = loc(_iPntSel.x(),_iPntSel.y());
-    QChar selClass = charClass(_image[i].character);
+    const QChar selClass = charClass(_image[i].character);
     int x = _iPntSel.x();
     
     while ( ((x>0) ||