ref: 9a0c908fe3529afac4914d54e28ae152cb53dd45
parent: 9fc305ae0d3dcde4bc1e0d62dd7dd52e53862f11
author: mkf <mkf@cloud9p.org>
date: Tue Nov 28 20:57:04 EST 2023
pc/vga: refactor
--- a/pc/vga.c
+++ b/pc/vga.c
@@ -51,6 +51,7 @@
vga_scroll(int lines)
{int index;
+
index = 0;
while(index < VGA_WIDTH * (VGA_HEIGHT - lines))
{@@ -70,9 +71,7 @@
{vga_col = 0; /* cr */
if(vga_row == VGA_HEIGHT-1)
- {vga_scroll(1);
- }
else
vga_row++;
}
@@ -80,7 +79,6 @@
void
vga_putc(char c)
{- int index = vga_row * VGA_WIDTH + vga_col;
switch(c)
{case '\r':
@@ -95,29 +93,7 @@
return;
case '\b':
if(vga_col > 0)
- {- /* index points at current loction of cursor, which is empty. */
- vga_buf[index - 1] = vga_char(' ', vga_color);- vga_col--;
- }
-
- /*
- is the following needed? i wonder.
- i'm aware of no OSes that allow their raw terminal interface
- allow returing to previous lines.
- only Plan 9 console driver allows this on rio.
-
- maybe it's safer to skip it.... for now.
-
- else if(vga_row == 0)
- {- // we need a smarter terminal-ish version
- // smh like
- // vga_row = vga_find_last_nonchar(' ');-
- vga_row = VGA_WIDTH;
- }
- */
+ vga_writeto(' ', vga_color, vga_row, --vga_col);return;
default: