int
write(const void *buf, int count)
{
int old;
int row;
int col;
char *s;
old=count;
s=(char*)buf;
while (count--)
{
#ifdef CONFIG_X86_64
vga_getpos(&row, &col);
switch (*s)
{
case '\r':
vga_setpos(row, 0);
break;
case '\n':
if (row<VGA_ROWS-1)
vga_setpos(row+1, col);
else
vga_scroll();
break;
default:
vga_drawc(*s);
if (col<VGA_COLS-1)
vga_setpos(row, col+1);
else if (row<VGA_ROWS-1)
vga_setpos(row+1, 0);
else
{
vga_setpos(row, 0);
vga_scroll();
}
}
#endif
s++;
}
return (old-count);
}
/*
* Update the vga position.
* depending on the current position we will scroll the screen up.
*/
void vga_update_pos(struct vga_console *vga, u8 nlFlg)
{
if (nlFlg)
{
if (vga->row == 24)
{
vga->col = 0;
vga_scroll((void *)vga, 25);
vga_movecursor((void *)vga, vga->row, vga->col);
return;
}
else
{
vga->col = 0;
vga->row++;
vga_movecursor((void *)vga, vga->row, vga->col);
return;
}
}
/*
* If we are the last row, column, scroll up by one row.
* Otherwise we just increment the row and col.
*/
if ((vga->row == 24) && (vga->col == 79))
{
vga_scroll ((void *)vga, 25);
vga->col = 0;
return;
}
if (vga->col == 79)
{
vga->col = 0;
vga->row++;
return;
}
vga->col ++;
vga_movecursor((void *)vga, vga->row, vga->col);
return;
}
void vga_putc(char c)
{
uint16_t *addr;
if (c == '\r') {
curx = 0;
} else if (VGA_PRINTABLE(c)) {
addr = (uint16_t*)VGA_MEMSTART + cury * VGA_COLS + curx;
*addr = VGA_CHAR(c);
++curx;
}
if (c == '\n' || curx == VGA_COLS)
vga_newline();
if (cury == VGA_ROWS) {
vga_scroll();
--cury;
}
}
void vga_print_char(const char c)
{
/* backspace */
if (c == '\b') {
if (xpos > 0) {
--xpos;
} else if (ypos > 0) {
xpos = COLS - 1;
--ypos;
}
}
/* tab -> increment xpos to a point that will make it
* divisible by 8. */
else if (c == '\t') {
xpos = (xpos + 8) & ~(8 - 1);
}
/* carriage return */
else if (c == '\r') {
xpos = 0;
}
/* newline */
else if (c == '\n') {
xpos = 0;
++ypos;
}
/* any character greater than and including a space is
* a printable character */
else if (c >= ' ') {
uint16_t *pos = video_mem + (ypos * COLS + xpos);
*pos = (uint16_t)c | attribute;
++xpos;
}
if (xpos >= COLS) {
xpos = 0;
++ypos;
}
vga_scroll();
set_cursor_pos(xpos, ypos);
}
