-int chvt(int vt) {
- _cleanup_close_ int fd;
-
- fd = open_terminal("/dev/tty0", O_RDWR|O_NOCTTY|O_CLOEXEC);
- if (fd < 0)
- return -errno;
-
- if (vt < 0) {
- int tiocl[2] = {
- TIOCL_GETKMSGREDIRECT,
- 0
- };
-
- if (ioctl(fd, TIOCLINUX, tiocl) < 0)
- return -errno;
-
- vt = tiocl[0] <= 0 ? 1 : tiocl[0];
- }
-
- if (ioctl(fd, VT_ACTIVATE, vt) < 0)
- return -errno;
-
- return 0;
-}
-
-int read_one_char(FILE *f, char *ret, usec_t t, bool *need_nl) {
- struct termios old_termios, new_termios;
- char c, line[LINE_MAX];
-
- assert(f);
- assert(ret);
-
- if (tcgetattr(fileno(f), &old_termios) >= 0) {
- new_termios = old_termios;
-
- new_termios.c_lflag &= ~ICANON;
- new_termios.c_cc[VMIN] = 1;
- new_termios.c_cc[VTIME] = 0;
-
- if (tcsetattr(fileno(f), TCSADRAIN, &new_termios) >= 0) {
- size_t k;
-
- if (t != USEC_INFINITY) {
- if (fd_wait_for_event(fileno(f), POLLIN, t) <= 0) {
- tcsetattr(fileno(f), TCSADRAIN, &old_termios);
- return -ETIMEDOUT;
- }
- }
-
- k = fread(&c, 1, 1, f);
-
- tcsetattr(fileno(f), TCSADRAIN, &old_termios);
-
- if (k <= 0)
- return -EIO;
-
- if (need_nl)
- *need_nl = c != '\n';
-
- *ret = c;
- return 0;
- }
- }
-
- if (t != USEC_INFINITY) {
- if (fd_wait_for_event(fileno(f), POLLIN, t) <= 0)
- return -ETIMEDOUT;
- }
-
- errno = 0;
- if (!fgets(line, sizeof(line), f))
- return errno ? -errno : -EIO;
-
- truncate_nl(line);
-
- if (strlen(line) != 1)
- return -EBADMSG;
-
- if (need_nl)
- *need_nl = false;
-
- *ret = line[0];
- return 0;
-}
-
-int ask_char(char *ret, const char *replies, const char *text, ...) {
- int r;
-
- assert(ret);
- assert(replies);
- assert(text);
-
- for (;;) {
- va_list ap;
- char c;
- bool need_nl = true;
-
- if (on_tty())
- fputs(ANSI_HIGHLIGHT_ON, stdout);
-
- va_start(ap, text);
- vprintf(text, ap);
- va_end(ap);
-
- if (on_tty())
- fputs(ANSI_HIGHLIGHT_OFF, stdout);
-
- fflush(stdout);
-
- r = read_one_char(stdin, &c, USEC_INFINITY, &need_nl);
- if (r < 0) {
-
- if (r == -EBADMSG) {
- puts("Bad input, please try again.");
- continue;
- }
-
- putchar('\n');
- return r;
- }
-
- if (need_nl)
- putchar('\n');
-
- if (strchr(replies, c)) {
- *ret = c;
- return 0;
- }
-
- puts("Read unexpected character, please try again.");
- }
-}
-
-int ask_string(char **ret, const char *text, ...) {
- assert(ret);
- assert(text);
-
- for (;;) {
- char line[LINE_MAX];
- va_list ap;
-
- if (on_tty())
- fputs(ANSI_HIGHLIGHT_ON, stdout);
-
- va_start(ap, text);
- vprintf(text, ap);
- va_end(ap);
-
- if (on_tty())
- fputs(ANSI_HIGHLIGHT_OFF, stdout);
-
- fflush(stdout);
-
- errno = 0;
- if (!fgets(line, sizeof(line), stdin))
- return errno ? -errno : -EIO;
-
- if (!endswith(line, "\n"))
- putchar('\n');
- else {
- char *s;
-
- if (isempty(line))
- continue;
-
- truncate_nl(line);
- s = strdup(line);
- if (!s)
- return -ENOMEM;
-
- *ret = s;
- return 0;
- }
- }
-}
-
-int reset_terminal_fd(int fd, bool switch_to_text) {
- struct termios termios;
- int r = 0;
-
- /* Set terminal to some sane defaults */
-
- assert(fd >= 0);
-
- /* We leave locked terminal attributes untouched, so that
- * Plymouth may set whatever it wants to set, and we don't
- * interfere with that. */
-
- /* Disable exclusive mode, just in case */
- ioctl(fd, TIOCNXCL);
-
- /* Switch to text mode */
- if (switch_to_text)
- ioctl(fd, KDSETMODE, KD_TEXT);
-
- /* Enable console unicode mode */
- ioctl(fd, KDSKBMODE, K_UNICODE);
-
- if (tcgetattr(fd, &termios) < 0) {
- r = -errno;
- goto finish;
- }
-
- /* We only reset the stuff that matters to the software. How
- * hardware is set up we don't touch assuming that somebody
- * else will do that for us */
-
- termios.c_iflag &= ~(IGNBRK | BRKINT | ISTRIP | INLCR | IGNCR | IUCLC);
- termios.c_iflag |= ICRNL | IMAXBEL | IUTF8;
- termios.c_oflag |= ONLCR;
- termios.c_cflag |= CREAD;
- termios.c_lflag = ISIG | ICANON | IEXTEN | ECHO | ECHOE | ECHOK | ECHOCTL | ECHOPRT | ECHOKE;
-
- termios.c_cc[VINTR] = 03; /* ^C */
- termios.c_cc[VQUIT] = 034; /* ^\ */
- termios.c_cc[VERASE] = 0177;
- termios.c_cc[VKILL] = 025; /* ^X */
- termios.c_cc[VEOF] = 04; /* ^D */
- termios.c_cc[VSTART] = 021; /* ^Q */
- termios.c_cc[VSTOP] = 023; /* ^S */
- termios.c_cc[VSUSP] = 032; /* ^Z */
- termios.c_cc[VLNEXT] = 026; /* ^V */
- termios.c_cc[VWERASE] = 027; /* ^W */
- termios.c_cc[VREPRINT] = 022; /* ^R */
- termios.c_cc[VEOL] = 0;
- termios.c_cc[VEOL2] = 0;
-
- termios.c_cc[VTIME] = 0;
- termios.c_cc[VMIN] = 1;
-
- if (tcsetattr(fd, TCSANOW, &termios) < 0)
- r = -errno;
-
-finish:
- /* Just in case, flush all crap out */
- tcflush(fd, TCIOFLUSH);
-
- return r;
-}
-
-int reset_terminal(const char *name) {
- _cleanup_close_ int fd = -1;
-
- fd = open_terminal(name, O_RDWR|O_NOCTTY|O_CLOEXEC);
- if (fd < 0)
- return fd;
-
- return reset_terminal_fd(fd, true);
-}
-
-int open_terminal(const char *name, int mode) {
- int fd, r;
- unsigned c = 0;
-
- /*
- * If a TTY is in the process of being closed opening it might
- * cause EIO. This is horribly awful, but unlikely to be
- * changed in the kernel. Hence we work around this problem by
- * retrying a couple of times.
- *
- * https://bugs.launchpad.net/ubuntu/+source/linux/+bug/554172/comments/245
- */
-
- assert(!(mode & O_CREAT));
-
- for (;;) {
- fd = open(name, mode, 0);
- if (fd >= 0)
- break;
-
- if (errno != EIO)
- return -errno;
-
- /* Max 1s in total */
- if (c >= 20)
- return -errno;
-
- usleep(50 * USEC_PER_MSEC);
- c++;
- }
-
- r = isatty(fd);
- if (r < 0) {
- safe_close(fd);
- return -errno;
- }
-
- if (!r) {
- safe_close(fd);
- return -ENOTTY;
- }
-
- return fd;
-}
-