implement scrollup

arch/textwindow.cc

@@ -1,5 +1,6 @@
 #include "textwindow.h"
 #include "cga.h"
+#include "../utils/string.h"
 
 TextWindow::TextWindow(unsigned from_col, unsigned to_col, unsigned from_row,
                        unsigned to_row, bool use_cursor) {
@@ -49,6 +50,12 @@ void TextWindow::getPos(int& rel_x, int& rel_y) const {
     rel_y = y;
 }
 
+void TextWindow::scrollUp(){
+    for(uint8_t row = from_row; row < to_row; row++){
+        memmove(&CGA::TEXT_BUFFER_BASE[row*CGA::COLUMNS + from_col], &CGA::TEXT_BUFFER_BASE[(row+1)*CGA::COLUMNS + from_col], 2*(to_col-from_col));
+    }
+}
+
 void TextWindow::print(const char* str, size_t length, CGA::Attribute attrib) {
     for(unsigned i=0; i<length; i++){
         unsigned x_now, y_now;
@@ -56,7 +63,7 @@ void TextWindow::print(const char* str, size_t length, CGA::Attribute attrib) {
         if(str[i] == '\n'){
             x_now = 0;
             if(from_row + y_now >= to_row-1){
-                //TODO scrollUp()
+                scrollUp();
             }
             else{
                 y_now++;

arch/textwindow.h

@@ -29,6 +29,8 @@ class TextWindow {
   unsigned 	pos_x;
   unsigned 	pos_y;
 
+  void scrollUp();
+
  public:
   /*! \brief Constructor of a text window
    *