This commit is contained in:
wescande 2018-02-12 16:49:30 +01:00
parent b730734cef
commit 097dfd7ddc

View file

@ -1,175 +0,0 @@
// Copyright 2016 Philipp Oppermann. See the README.md
// file at the top-level directory of this distribution.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.
use core::ptr::Unique;
use core::fmt;
use spin::Mutex;
use volatile::Volatile;
const BUFFER_HEIGHT: usize = 25;
const BUFFER_WIDTH: usize = 80;
pub static WRITER: Mutex<Writer> = Mutex::new(Writer {
column_position: 0,
color_code: ColorCode::new(Color::White, Color::Black),
vgabuffer: unsafe { Unique::new_unchecked(0xb8000 as *mut _) },
});
// cursor is lightgray for everyone
static CURSOR: ScreenChar = ScreenChar {
ascii_character: b' ',
color_code: ColorCode::new(Color::LightGray, Color::LightGray),
};
// blank is black for everyone, could make screens choose this
static BLANK: ScreenChar = ScreenChar {
ascii_character: b' ',
color_code: ColorCode::new(Color::White, Color::Black),
};
pub struct Writer {
column_position: usize,
pub color_code: ColorCode,
vgabuffer: Unique<Buffer>,
}
macro_rules! println {
($fmt:expr) => (print!(concat!($fmt, "\n")));
($fmt:expr, $($arg:tt)*) => (print!(concat!($fmt, "\n"), $($arg)*));
}
macro_rules! print {
($($arg:tt)*) => ({
$crate::vga_buffer::print(format_args!($($arg)*));
});
}
pub fn print(args: fmt::Arguments) {
use core::fmt::Write;
WRITER.lock().write_fmt(args).unwrap();
}
impl Writer {
pub fn reset_screen(&mut self)
{
let color_code = self.color_code;
for row in 1..BUFFER_HEIGHT {
for col in 0..BUFFER_WIDTH {
self.buffer().chars[row][col].write(ScreenChar {
ascii_character: b' ',
color_code,
});
}
}
self.column_position = 0;
}
pub fn write_byte(&mut self, byte: u8) {
match byte {
b'\n' => self.new_line(),
byte => {
if self.column_position >= BUFFER_WIDTH {
self.new_line();
}
let row = BUFFER_HEIGHT - 1;
let col = self.column_position;
let color_code = self.color_code;
self.buffer().chars[row][col].write(ScreenChar {
ascii_character: byte,
color_code: color_code,
});
self.column_position += 1;
}
}
if self.column_position >= BUFFER_WIDTH {
self.new_line();
}
let row = BUFFER_HEIGHT - 1;
let col = self.column_position;
self.buffer().chars[row][col].write(CURSOR);
}
fn buffer(&mut self) -> &mut Buffer {
unsafe { self.vgabuffer.as_mut() }
}
fn new_line(&mut self) {
// remove cursor if newline isnt from end of screen
if self.column_position < BUFFER_WIDTH {
let col = self.column_position;
self.buffer().chars[BUFFER_HEIGHT - 1][col].write(BLANK);
}
for row in 1..BUFFER_HEIGHT {
for col in 0..BUFFER_WIDTH {
let buffer = self.buffer();
let character = buffer.chars[row][col].read();
buffer.chars[row - 1][col].write(character);
}
}
self.clear_row(BUFFER_HEIGHT - 1);
self.column_position = 0;
}
fn clear_row(&mut self, row: usize) {
for col in 0..BUFFER_WIDTH {
self.buffer().chars[row][col].write(BLANK);
}
}
}
impl fmt::Write for Writer {
fn write_str(&mut self, s: &str) -> ::core::fmt::Result {
for byte in s.bytes() {
self.write_byte(byte)
}
Ok(())
}
}
#[allow(dead_code)]
#[derive(Debug, Clone, Copy)]
#[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)]
pub struct ColorCode(u8);
impl ColorCode {
pub const fn new(foreground: Color, background: Color) -> ColorCode {
ColorCode((background as u8) << 4 | (foreground as u8))
}
}
#[derive(Debug, Clone, Copy)]
#[repr(C)]
struct ScreenChar {
ascii_character: u8,
color_code: ColorCode,
}
struct Buffer {
chars: [[Volatile<ScreenChar>; BUFFER_WIDTH]; BUFFER_HEIGHT],
}