1 /* vi: set sw=4 ts=4: */
5 * Copyright (c) 2007 Denys Vlasenko <vda.linux@googlemail.com>
9 /* From <linux/vt.h> */
11 unsigned short v_active; /* active vt */
12 unsigned short v_signal; /* signal to send */
13 unsigned short v_state; /* vt bitmask */
15 enum { VT_GETSTATE = 0x5603 }; /* get global vt state info */
17 /* From <linux/serial.h> */
18 struct serial_struct {
27 unsigned short close_delay;
29 char reserved_char[1];
31 unsigned short closing_wait; /* time to wait before closing */
32 unsigned short closing_wait2; /* no longer used... */
33 unsigned char *iomem_base;
34 unsigned short iomem_reg_shift;
35 unsigned int port_high;
36 unsigned long iomap_base; /* cookie passed into ioremap */
40 int cttyhack_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
41 int cttyhack_main(int argc UNUSED_PARAM, char **argv)
44 char console[sizeof(int)*3 + 16];
47 struct serial_struct sr;
48 char paranoia[sizeof(struct serial_struct) * 3];
55 strcpy(console, "/dev/tty");
56 if (ioctl(0, TIOCGSERIAL, &u.sr) == 0) {
57 /* this is a serial console */
58 sprintf(console + 8, "S%d", u.sr.line);
59 } else if (ioctl(0, VT_GETSTATE, &u.vt) == 0) {
60 /* this is linux virtual tty */
61 sprintf(console + 8, "S%d" + 1, u.vt.v_active);
65 fd = xopen(console, O_RDWR);
66 //bb_error_msg("switching to '%s'", console);
70 while (fd > 2) close(fd--);
71 /* Some other session may have it as ctty. Steal it from them */
72 ioctl(0, TIOCSCTTY, 1);
75 BB_EXECVP(argv[0], argv);
76 bb_perror_msg_and_die("can't execute '%s'", argv[0]);