Now passes first vttest test (implemented RI and NEL)

terminalframebuffer.cpp

@@ -66,13 +66,21 @@ Framebuffer::Framebuffer( int s_width, int s_height )
 
 void Framebuffer::scroll( int N )
 {
-  assert( N >= 0 );
+  if ( N >= 0 ) {
-
     for ( int i = 0; i < N; i++ ) {
       rows.pop_front();
       rows.push_back( Row( ds.get_width() ) );
       ds.move_row( -1, true );
     }
+  } else {
+    N = -N;
+
+    for ( int i = 0; i < N; i++ ) {
+      rows.pop_back();
+      rows.push_front( Row( ds.get_width() ) );
+      ds.move_row( 1, true );
+    }
+  }
 }
 
 void DrawState::new_grapheme( void )
@@ -129,6 +137,8 @@ void Framebuffer::move_rows_autoscroll( int rows )
 {
   if ( ds.get_cursor_row() + rows >= ds.get_height() ) {
     scroll( ds.get_height() - ds.get_cursor_row() - rows + 1 );
+  } else if ( ds.get_cursor_row() + rows < 0 ) {
+    scroll( ds.get_cursor_row() + rows );
   }
 
   ds.move_row( rows, true );

terminalfunctions.cpp

@@ -127,3 +127,17 @@ void Ctrl_BS( Framebuffer *fb, Dispatcher *dispatch __attribute((unused)) )
 
 static Function func_Ctrl_BS( CONTROL, "\x08", Ctrl_BS );
 
+void Ctrl_RI( Framebuffer *fb, Dispatcher *dispatch __attribute((unused)) )
+{
+  fb->move_rows_autoscroll( -1 );
+}
+
+static Function func_Ctrl_RI( CONTROL, "\x8D", Ctrl_RI );
+
+void Ctrl_NEL( Framebuffer *fb, Dispatcher *dispatch __attribute((unused)) )
+{
+  fb->ds.move_col( 0 );
+  fb->move_rows_autoscroll( 1 );
+}
+
+static Function func_Ctrl_NEL( CONTROL, "\x85", Ctrl_NEL );