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/*
* GRUB -- GRand Unified Bootloader
* Copyright (C) 2007, 2008, 2010 Free Software Foundation, Inc.
*
* GRUB is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* GRUB is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with GRUB. If not, see <http://www.gnu.org/licenses/>.
*/
#include <grub/dl.h>
#include <grub/i386/vga_common.h>
#include <grub/i386/io.h>
#include <grub/types.h>
#include <grub/vga.h>
GRUB_MOD_LICENSE ("GPLv3+");
#define COLS 80
#define ROWS 25
static int grub_curr_x, grub_curr_y;
#define VGA_TEXT_SCREEN ((grub_uint16_t *) 0xb8000)
static void
screen_write_char (int x, int y, short c)
{
VGA_TEXT_SCREEN[y * COLS + x] = c;
}
static short
screen_read_char (int x, int y)
{
return VGA_TEXT_SCREEN[y * COLS + x];
}
static void
update_cursor (void)
{
unsigned int pos = grub_curr_y * COLS + grub_curr_x;
grub_vga_cr_write (pos >> 8, GRUB_VGA_CR_CURSOR_ADDR_HIGH);
grub_vga_cr_write (pos & 0xFF, GRUB_VGA_CR_CURSOR_ADDR_LOW);
}
static void
inc_y (void)
{
grub_curr_x = 0;
if (grub_curr_y < ROWS - 1)
grub_curr_y++;
else
{
int x, y;
for (y = 0; y < ROWS - 1; y++)
for (x = 0; x < COLS; x++)
screen_write_char (x, y, screen_read_char (x, y + 1));
for (x = 0; x < COLS; x++)
screen_write_char (x, ROWS - 1, ' ' | (grub_console_cur_color << 8));
}
}
static void
inc_x (void)
{
if (grub_curr_x >= COLS - 1)
inc_y ();
else
grub_curr_x++;
}
static void
grub_vga_text_putchar (struct grub_term_output *term __attribute__ ((unused)),
const struct grub_unicode_glyph *c)
{
switch (c->base)
{
case '\b':
if (grub_curr_x != 0)
screen_write_char (grub_curr_x--, grub_curr_y, ' ');
break;
case '\n':
inc_y ();
break;
case '\r':
grub_curr_x = 0;
break;
default:
screen_write_char (grub_curr_x, grub_curr_y,
c->base | (grub_console_cur_color << 8));
inc_x ();
}
update_cursor ();
}
static grub_uint16_t
grub_vga_text_getxy (struct grub_term_output *term __attribute__ ((unused)))
{
return (grub_curr_x << 8) | grub_curr_y;
}
static void
grub_vga_text_gotoxy (struct grub_term_output *term __attribute__ ((unused)),
grub_uint8_t x, grub_uint8_t y)
{
grub_curr_x = x;
grub_curr_y = y;
update_cursor ();
}
static void
grub_vga_text_cls (struct grub_term_output *term)
{
int i;
for (i = 0; i < ROWS * COLS; i++)
VGA_TEXT_SCREEN[i] = ' ' | (grub_console_cur_color << 8);
grub_vga_text_gotoxy (term, 0, 0);
}
static void
grub_vga_text_setcursor (struct grub_term_output *term __attribute__ ((unused)),
int on)
{
grub_uint8_t old;
old = grub_vga_cr_read (GRUB_VGA_CR_CURSOR_START);
if (on)
grub_vga_cr_write (old & ~GRUB_VGA_CR_CURSOR_START_DISABLE,
GRUB_VGA_CR_CURSOR_START);
else
grub_vga_cr_write (old | GRUB_VGA_CR_CURSOR_START_DISABLE,
GRUB_VGA_CR_CURSOR_START);
}
static grub_err_t
grub_vga_text_init_fini (struct grub_term_output *term)
{
grub_vga_text_cls (term);
return 0;
}
static struct grub_term_output grub_vga_text_term =
{
.name = "vga_text",
.init = grub_vga_text_init_fini,
.fini = grub_vga_text_init_fini,
.putchar = grub_vga_text_putchar,
.getwh = grub_console_getwh,
.getxy = grub_vga_text_getxy,
.gotoxy = grub_vga_text_gotoxy,
.cls = grub_vga_text_cls,
.setcolorstate = grub_console_setcolorstate,
.setcursor = grub_vga_text_setcursor,
.flags = GRUB_TERM_CODE_TYPE_CP437,
.normal_color = GRUB_TERM_DEFAULT_NORMAL_COLOR,
.highlight_color = GRUB_TERM_DEFAULT_HIGHLIGHT_COLOR,
};
GRUB_MOD_INIT(vga_text)
{
grub_term_register_output ("vga_text", &grub_vga_text_term);
}
GRUB_MOD_FINI(vga_text)
{
grub_term_unregister_output (&grub_vga_text_term);
}
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