geos/kernel/std/src/vga_buffer.rs
2024-03-27 16:29:04 +01:00

133 lines
2.9 KiB
Rust

use core::fmt::{self, Write};
use lazy_static::lazy_static;
use spin::Mutex;
#[derive(Debug, Clone, Copy, PartialEq, Eq)]
#[repr(u8)]
pub enum Color {
Black = 0,
Blue = 1,
Green = 2,
Cyan = 3,
Red = 4,
Magenta = 5,
Brown = 6,
LightGray = 7,
DarkGray = 8,
LightBlue = 9,
LightGreen = 10,
LightCyan = 11,
LightRed = 12,
Pink = 13,
Yellow = 14,
White = 15,
}
#[derive(Debug, Clone, Copy, PartialEq, Eq)]
#[repr(transparent)]
pub struct ColorCode(u8);
impl ColorCode {
pub fn new(foreground: Color, background: Color) -> ColorCode {
ColorCode((background as u8) << 4 | (foreground as u8))
}
}
#[derive(Debug, Clone, Copy, PartialEq, Eq)]
#[repr(C)]
struct ScreenChar {
ascii_character: u8,
color_code: ColorCode,
}
const BUFFER_HEIGHT: usize = 25;
const BUFFER_WIDTH: usize = 80;
#[repr(transparent)]
struct Buffer {
chars: [[ScreenChar; BUFFER_WIDTH]; BUFFER_HEIGHT],
}
pub struct Writer {
col: usize,
row: usize,
buffer: &'static mut Buffer,
}
impl Writer {
pub fn write_byte(&mut self, byte: u8) {
self.write_byte_color(byte, ColorCode::new(Color::White, Color::Black));
}
pub fn write_byte_color(&mut self, byte: u8, color: ColorCode) {
match byte {
b'\n' => self.new_line(),
byte => {
if self.col >= BUFFER_WIDTH {
self.new_line();
}
let row = self.row;
let col = self.col;
let color_code = color;
self.buffer.chars[row][col] = ScreenChar {
ascii_character: byte,
color_code,
};
self.col += 1;
}
}
}
pub fn write_string(&mut self, s: &str) {
self.write_string_color(s, ColorCode::new(Color::White, Color::Black));
}
pub fn write_string_color(&mut self, s: &str, color: ColorCode) {
for char in s.bytes() {
match char {
0x20..=0x7e | b'\n' => self.write_byte_color(char, color),
_ => self.write_byte(0xfe),
}
}
}
fn new_line(&mut self) {
self.row += 1;
self.col = 0;
}
}
impl fmt::Write for Writer {
fn write_str(&mut self, s: &str) -> fmt::Result {
self.write_string(s);
Ok(())
}
}
lazy_static! {
pub static ref WRITER: Mutex<Writer> = Mutex::new(Writer {
col: 0,
row: 0,
buffer: unsafe { &mut *(0xB8000 as *mut Buffer) },
});
}
#[doc(hidden)]
pub fn _print(args: fmt::Arguments) {
WRITER.lock().write_fmt(args).unwrap()
}
#[macro_export]
macro_rules! print {
($($arg:tt)*) => ($crate::vga_buffer::_print(format_args!($($arg)*)));
}
#[macro_export]
macro_rules! println {
() => ($crate::print!("\n"));
($($arg:tt)*) => ($crate::print!("{}\n", format_args!($($arg)*)));
}