Added support for certain control characters and hardware cursor

src/term.c

@@ -5,6 +5,7 @@
 */
 */
 
 
 #include "term.h"
 #include "term.h"
+#include "asm.h"
 
 
 uint8_t make_color(enum vga_color fg, enum vga_color bg) 
 uint8_t make_color(enum vga_color fg, enum vga_color bg) 
 {
 {
@@ -26,6 +27,15 @@ size_t terminal_column;
 uint8_t terminal_color;
 uint8_t terminal_color;
 uint16_t* terminal_buffer;
 uint16_t* terminal_buffer;
 
 
+void update_csr()
+{
+    unsigned temp = terminal_row*80+terminal_column;
+    outb(0x3D4,14);
+    outb(0x3D5,temp>>8);
+    outb(0x3D4, 15);
+    outb(0x3D5, temp);
+}
+
 void terminal_initialize() 
 void terminal_initialize() 
 {
 {
     terminal_row = 0;
     terminal_row = 0;
@@ -55,6 +65,27 @@ void terminal_putentryat(char c, uint8_t color, size_t x, size_t y)
 
 
 void terminal_putchar(char c) 
 void terminal_putchar(char c) 
 {
 {
+    if(c=='\b')
+    {
+	if(terminal_column == 0)
+	{
+	    terminal_row--;
+	    terminal_column=VGA_WIDTH;
+	}
+	terminal_column--;
+	terminal_putentryat(' ',terminal_color, terminal_column,terminal_row);
+    }
+    else if(c=='\n')
+    {
+	terminal_column=0;
+	terminal_row++;
+    }
+    else if(c=='\t')
+    {
+	terminal_writestring("    ");
+    }
+    else
+    {
 	terminal_putentryat(c, terminal_color, terminal_column, terminal_row);
 	terminal_putentryat(c, terminal_color, terminal_column, terminal_row);
 	if (++terminal_column == VGA_WIDTH) 
 	if (++terminal_column == VGA_WIDTH) 
 	{
 	{
@@ -64,6 +95,8 @@ void terminal_putchar(char c)
 		terminal_row = 0;
 		terminal_row = 0;
 	    }
 	    }
 	}
 	}
+    }
+    update_csr();
 }
 }
 
 
 void terminal_writestring(const char* data) 
 void terminal_writestring(const char* data)