Apply const qualifiers in Mapscript for strings (#6908)

mapscript/swiginc/label.i

@@ -85,7 +85,7 @@
   }
 
   /// Get the attribute binding for a specified label property. Returns NULL if there is no binding for this property.
-  char *getBinding(int binding) 
+  const char *getBinding(int binding) 
   {
     if(binding < 0 || binding >= MS_LABEL_BINDING_LENGTH) return NULL;
 
@@ -94,7 +94,7 @@
 
   /// Set the attribute binding for a specified label property. Binding constants look like this: ``MS_LABEL_BINDING_[attribute name]``:
   /// >>> new_label.setBinding(MS_LABEL_BINDING_COLOR, "FIELD_NAME_COLOR")
-  int setBinding(int binding, char *item) 
+  int setBinding(int binding, const char *item) 
   {
     if(!item) return MS_FAILURE;
     if(binding < 0 || binding >= MS_LABEL_BINDING_LENGTH) return MS_FAILURE;

mapscript/swiginc/map.i

@@ -31,7 +31,7 @@
 {
 
     /// Create a new instance of :class:`mapObj`. Note that the *filename* is optional.
-    mapObj(char *filename="", configObj *config=NULL) 
+    mapObj(const char *filename="", configObj *config=NULL) 
     {
         if (filename && strlen(filename))
             return msLoadMap(filename, NULL, config);
@@ -42,7 +42,7 @@
 
 #ifdef SWIGCSHARP
 
-  mapObj(char *filename) 
+  mapObj(const char *filename) 
   {
         if (filename && strlen(filename))
             return msLoadMap(filename, NULL, NULL);
@@ -249,7 +249,7 @@
         :func:`mapObj.setImageType` remains in the module but its use 
         is deprecated in favor of :func:`mapObj.selectOutputFormat`.
     */
-    void setImageType( char * imagetype ) {
+    void setImageType( const char * imagetype ) {
         outputFormatObj *format;
 
         format = msSelectOutputFormat( self, imagetype );
@@ -268,7 +268,7 @@
     Set the map's active output format to the internal format named imagetype. 
     Built-in formats are "PNG", "PNG24", "JPEG", "GIF", "GTIFF".
     */
-    void selectOutputFormat( char *imagetype )
+    void selectOutputFormat( const char *imagetype )
     {
         outputFormatObj *format;
 
@@ -656,7 +656,7 @@
     case insensitive and allows an output format to be found either by driver 
     (like 'AGG/PNG') or name (like 'png').
     */
-    outputFormatObj *getOutputFormatByName(char *name) {
+    outputFormatObj *getOutputFormatByName(const char *name) {
         return msSelectOutputFormat(self, name); 
     }
 
@@ -668,7 +668,7 @@
 
     /// Removes the format named name from the map's output format list. 
     /// Returns :data:`MS_SUCCESS` or :data:`MS_FAILURE`
-    int removeOutputFormat(char *name) {
+    int removeOutputFormat(const char *name) {
         return msRemoveOutputFormat(self, name);
     }
 

mapscript/swiginc/style.i

@@ -158,7 +158,7 @@
     }
 
     /// Remove the attribute binding for a specified style property. 
-    int setBinding(int binding, char *item) 
+    int setBinding(int binding, const char *item) 
     {
         if(!item) return MS_FAILURE;
         if(binding < 0 || binding >= MS_STYLE_BINDING_LENGTH) return MS_FAILURE;
@@ -178,7 +178,7 @@
 
     /// Get the attribute binding for a specified style property. 
     /// Returns NULL if there is no binding for this property. 
-    char *getBinding(int binding) 
+    const char *getBinding(int binding) 
     {
         if(binding < 0 || binding >= MS_STYLE_BINDING_LENGTH) return NULL;