print_int function

Just to print integer outputs of things on the screen

rust_experiments/src/lib.rs

@@ -21,6 +21,10 @@ pub extern fn rust_main() {
         }
     }
 
+    vga_buffer::print_int(1, 5);
+    vga_buffer::print_int(10, 6);
+    vga_buffer::print_int(765, 6);
+
     loop {}
 }
 
@@ -105,6 +109,26 @@ mod vga_buffer {
         }
     }
 
+    pub fn print_int(i: u32, row: usize) {
+        let mut val = i;
+        let mut ptr = BUFFER_PTR + BUFFER_WIDTH*2*(row+1) - 2 as usize;
+        let color_code = ColorCode::new(Color::White, Color::Black);
+        loop {
+            if val < 10 {
+                let ch: u8 = b'0' + (val as u8);
+                let data = ScreenChar { ascii_char: ch, color_code: color_code };
+                unsafe { *(ptr as *mut _) = data; }
+                break;
+            } else {
+                let ch: u8 = b'0' + ((val % 10) as u8) ;
+                val = val / 10;
+                let data = ScreenChar { ascii_char: ch, color_code: color_code };
+                unsafe { *(ptr as *mut _) = data; }
+                ptr -= 2;
+            }
+        }
+    }
+
     pub fn write_to_coord(x: usize, y: usize, character: u8, color_code: ColorCode) {
         let ptr = BUFFER_PTR + (2*x as usize) + (BUFFER_WIDTH*2*y as usize);
         let data = ScreenChar {