initscripts/src/console_check.c

   1
   2 #include <fcntl.h>
   3 #include <stdio.h>
   4 #include <stdlib.h>
   5 #include <string.h>
   6 #include <termios.h>
   7 #include <unistd.h>
   8
   9 #include <sys/ioctl.h>
  10
  11 #include <linux/serial.h>
  12 #include <linux/serial_core.h>
  13
  14 struct speeds
  15 {
  16         speed_t speed;
  17         unsigned long value;
  18 };
  19
  20 struct speeds speed_map[] =
  21 {
  22         {B50, 50},
  23         {B75, 75},
  24         {B110, 110},
  25         {B134, 134},
  26         {B150, 150},
  27         {B200, 200},
  28         {B300, 300},
  29         {B600, 600},
  30         {B1200, 1200},
  31         {B1800, 1800},
  32         {B2400, 2400},
  33         {B4800, 4800},
  34         {B9600, 9600},
  35         {B19200, 19200},
  36         {B38400, 38400},
  37 #ifdef B57600
  38         {B57600, 57600},
  39 #endif
  40 #ifdef B115200
  41         {B115200, 115200},
  42 #endif
  43 #ifdef B230400
  44         {B230400, 230400},
  45 #endif
  46 #ifdef B460800
  47         {B460800, 460800},
  48 #endif
  49         {0, 0}
  50 };
  51
  52 int termcmp(struct termios *a, struct termios *b) {
  53         if (a->c_iflag != b->c_iflag || a->c_oflag != b->c_oflag ||
  54             a->c_cflag != b->c_cflag || a->c_lflag != b->c_lflag ||
  55             cfgetispeed(a) != cfgetispeed(b) || cfgetospeed(a) != cfgetospeed(b))
  56                 return 1;
  57         return memcmp(a->c_cc, b->c_cc, sizeof(a->c_cc));
  58 }
  59
  60 int get_serial_speed(int fd) {
  61         struct termios mode;
  62
  63         if (!tcgetattr(fd, &mode)) {
  64                 int i;
  65                 speed_t speed;
  66
  67                 speed = cfgetospeed(&mode);
  68                 for (i = 0; speed_map[i].value != 0; i++)
  69                         if (speed_map[i].speed == speed)
  70                                 return speed_map[i].value;
  71         }
  72         return 0;
  73 }
  74
  75 int compare_termios_to_console(char *dev, int *speed) {
  76         struct termios cmode, mode;
  77         int fd, cfd;
  78
  79         cfd = open ("/dev/console", O_RDONLY);
  80         tcgetattr(cfd, &cmode);
  81         close(cfd);
  82
  83         fd = open(dev, O_RDONLY|O_NONBLOCK);
  84         tcgetattr(fd, &mode);
  85
  86         if (!termcmp(&cmode, &mode)) {
  87                 *speed = get_serial_speed(fd);
  88                 close(fd);
  89                 return 1;
  90         }
  91         close(fd);
  92         return 0;
  93 }
  94
  95 char *serial_tty_name(int type) {
  96         switch (type) {
  97                 case PORT_8250...PORT_MAX_8250:
  98                         return "ttyS";
  99                 case PORT_PMAC_ZILOG:
 100                         return "ttyPZ";
 101                 case PORT_MPSC:
 102                         return "ttyMM";
 103                 case PORT_CPM:
 104                         return "ttyCPM";
 105                 case PORT_MPC52xx:
 106                         return "ttyPSC";
 107                 default:
 108                         return NULL;
 109         }
 110 }
 111
 112 char *check_serial_console(int *speed) {
 113         int fd;
 114         char *ret = NULL, *device;
 115         char twelve = 12;
 116         struct serial_struct si, si2;
 117         char *tty_name;
 118
 119         memset(&si, 0, sizeof(si));
 120         memset(&si2, 0, sizeof(si));
 121
 122         fd = open("/dev/console", O_RDWR);
 123         if (ioctl (fd, TIOCLINUX, &twelve) >= 0)
 124                 goto out;
 125
 126         if (ioctl(fd, TIOCGSERIAL, &si) < 0)
 127                 goto out;
 128         close(fd);
 129
 130         tty_name = serial_tty_name(si.type);
 131         if (!tty_name)
 132                 goto out;
 133
 134         asprintf(&device, "%s%d", tty_name, si.line);
 135         fd = open(device, O_RDWR|O_NONBLOCK);
 136         if (fd == -1)
 137                 goto out;
 138
 139         if (ioctl(fd, TIOCGSERIAL, &si2) < 0)
 140                 goto out;
 141
 142         if (memcmp(&si,&si2, sizeof(si)))
 143                 goto out;
 144
 145         *speed = get_serial_speed(fd);
 146         ret = device;
 147 out:
 148         close(fd);
 149         return ret;
 150 }
 151
 152 int emit_console_event(char *dev, int speed) {
 153         char *args[] = { "initctl", "emit", "--no-wait", "serial-console-available", NULL, NULL, NULL };
 154
 155         asprintf(&args[4],"DEV=%s", dev);
 156         if (speed)
 157                 asprintf(&args[5],"SPEED=%d", speed);
 158         execv("/sbin/initctl", args);
 159         return 1;
 160 }
 161
 162 int main(int argc, char **argv) {
 163         char *device;
 164         int speed;
 165
 166         if (argc < 2) {
 167                 printf("usage: console_check <device>\n");
 168                 exit(1);
 169         }
 170         chdir("/dev");
 171         device = argv[1];
 172         if (!strcmp(device, "console")) {
 173                 device = check_serial_console(&speed);
 174                 if (device)
 175                         return emit_console_event(device, speed);
 176         } else if (compare_termios_to_console(device, &speed)) {
 177                 return emit_console_event(device, speed);
 178         }
 179         return 0;
 180 }