Files
buffybox/terminal.c
2022-10-03 13:04:26 +02:00

138 lines
3.3 KiB
C

/**
* Copyright 2021 Johannes Marbach
*
* This file is part of unl0kr, hereafter referred to as the program.
*
* This program 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.
*
* This program 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 this program. If not, see <https://www.gnu.org/licenses/>.
*/
#include "terminal.h"
#include "log.h"
#include <fcntl.h>
#include <stdbool.h>
#include <unistd.h>
#include <linux/kd.h>
#include <sys/ioctl.h>
/**
* Static variables
*/
static int current_fd = -1;
static int original_mode = KD_TEXT;
static int original_kb_mode = K_UNICODE;
/**
* Static prototypes
*/
/**
* Close the current file descriptor and reopen /dev/tty0.
*
* @return true if opening was successful, false otherwise
*/
static bool reopen_current_terminal(void);
/**
* Close the current file descriptor.
*/
static void close_current_terminal(void);
/**
* Static functions
*/
static bool reopen_current_terminal(void) {
close_current_terminal();
current_fd = open("/dev/tty0", O_RDWR);
if (current_fd < 0) {
ul_log(UL_LOG_LEVEL_WARNING, "Could not open /dev/tty0");
return false;
}
return true;
}
static void close_current_terminal(void) {
if (current_fd < 0) {
return;
}
close(current_fd);
current_fd = -1;
}
/**
* Public functions
*/
void ul_terminal_prepare_current_terminal(void) {
reopen_current_terminal();
if (current_fd < 0) {
ul_log(UL_LOG_LEVEL_WARNING, "Could not prepare current terminal");
return;
}
// NB: The order of calls appears to matter for some devices. See
// https://gitlab.com/cherrypicker/unl0kr/-/issues/34 for further info.
if (ioctl(current_fd, KDGKBMODE, &original_kb_mode) != 0) {
ul_log(UL_LOG_LEVEL_WARNING, "Could not get terminal keyboard mode");
}
if (ioctl(current_fd, KDSKBMODE, K_OFF) != 0) {
ul_log(UL_LOG_LEVEL_WARNING, "Could not set terminal keyboard mode to off");
}
if (ioctl(current_fd, KDGETMODE, &original_mode) != 0) {
ul_log(UL_LOG_LEVEL_WARNING, "Could not get terminal mode");
}
if (ioctl(current_fd, KDSETMODE, KD_GRAPHICS) != 0) {
ul_log(UL_LOG_LEVEL_WARNING, "Could not set terminal mode to graphics");
}
}
void ul_terminal_reset_current_terminal(void) {
if (current_fd < 0) {
ul_log(UL_LOG_LEVEL_WARNING, "Could not reset current terminal");
return;
}
// NB: The order of calls appears to matter for some devices. See
// https://gitlab.com/cherrypicker/unl0kr/-/issues/34 for further info.
if (ioctl(current_fd, KDSETMODE, original_mode) != 0) {
ul_log(UL_LOG_LEVEL_WARNING, "Could not reset terminal mode");
}
if (ioctl(current_fd, KDSKBMODE, original_kb_mode) != 0) {
ul_log(UL_LOG_LEVEL_WARNING, "Could not reset terminal keyboard mode");
}
close_current_terminal();
}