Add: working puts implementation

stdio.c

@@ -3,25 +3,83 @@
 #include "string.h"
 
 char* fb = (char *) 0x000B8000;
+const unsigned VGA_WIDTH = 80;
+const unsigned VGA_HEIGHT = 25;
+const unsigned int COLOR = 0x7;
+unsigned int VGA_X = 0, VGA_Y = 0;
 
-void move_cursor(unsigned short pos)
+void move_cursor(int x, int y)
 {
+  unsigned short pos = y*VGA_WIDTH+x; 
+
   outb(FB_CMD_PORT, FB_HIGH_BYTE_CMD);
   outb(FB_DATA_PORT, ((pos >> 8) & 0x00FF));
   outb(FB_CMD_PORT, FB_LOW_BYTE_CMD);
   outb(FB_DATA_PORT, pos & 0x00FF);
 }
 
-void putchar(unsigned int i, char c, unsigned char fg, unsigned char bg)
+void putchar(int x, int y, char c) 
 {
-  fb[i] = c;
-  fb [i+1] = ((fg & 0x0F) << 4 | (bg & 0x0F));
+  fb[2*(y*VGA_WIDTH+x)] = c;
 }
 
-void write(char *buf)
+void putcolor(int x, int y, int color)
 {
-  for (int i=0; i<strlen(buf); i++)
+  fb[2*(y*VGA_WIDTH+x)+1] = color;
+}
+
+void clear(void)
+{
+  for (unsigned int y=0; y<VGA_HEIGHT; y++)
   {
-    putchar(2*i, buf[i], FB_GREEN, FB_DARK_GREY);
+    for (unsigned int x=0; x<VGA_WIDTH; x++)
+    {
+      putchar(x, y, '\0');
+      putcolor(x, y, COLOR);
+    }
+  }
+  VGA_X = 0;
+  VGA_Y = 0;
+  move_cursor(VGA_X, VGA_Y);
+}
+
+void putc(char c)
+{
+  switch(c)
+  {
+    case '\n':
+      VGA_X = 0;
+      VGA_Y++;
+      break;
+    case '\r':
+      VGA_X = 0;
+      break;
+    default:
+      putchar(VGA_X, VGA_Y, c);
+      VGA_X++;
+      break;
+  }
+
+  if (VGA_X >= VGA_WIDTH)
+  {
+    VGA_Y++;
+    VGA_X = 0;
+  }
+  //if (VGA_Y >= VGA_HEIGHT) scroll
+
+  move_cursor(VGA_X, VGA_Y);
+}
+
+void puts(const char* str)
+{
+  while (*str)
+  {
+    putc(*str);
+    str++;
   }
 }
+
+
+
+
+