lunaix-os/usr/init/init.c

   1 #include <errno.h>
   2 #include <fcntl.h>
   3 #include <lunaix/lunaix.h>
   4 #include <lunaix/mount.h>
   5 #include <termios.h>
   6 #include <stdio.h>
   7 #include <unistd.h>
   8
   9 #define must_mount(src, target, fs, opts)                                      \
  10     do {                                                                       \
  11         int err = 0;                                                           \
  12         if ((err = mount(src, target, fs, opts))) {                            \
  13             syslog(2, "mount fs %s to %s failed (%d)\n", fs, target, errno);   \
  14             return err;                                                        \
  15         }                                                                      \
  16     } while (0)
  17
  18 #define check(statement)                                      \
  19     do {                                                                       \
  20         int err = 0;                                                           \
  21         if ((err = (statement))) {                            \
  22             syslog(2, #statement " failed: %d", err);   \
  23             return err;                                                        \
  24         }                                                                      \
  25     } while (0)
  26
  27 int
  28 init_termios(int fd) {
  29     struct termios term;
  30
  31     check(tcgetattr(fd, &term));
  32
  33     term.c_lflag = ICANON | IEXTEN | ISIG | ECHO | ECHOE | ECHONL;
  34     term.c_iflag = ICRNL | IGNBRK;
  35     term.c_oflag = ONLCR | OPOST;
  36     term.c_cflag = CREAD | CLOCAL | CS8 | CPARENB;
  37     term.c_cc[VERASE] = 0x08;
  38
  39     check(tcsetattr(fd, 0, &term));
  40
  41     return 0;
  42 }
  43
  44 int
  45 main(int argc, const char** argv)
  46 {
  47     int err = 0;
  48
  49     mkdir("/dev");
  50     mkdir("/sys");
  51     mkdir("/task");
  52
  53     must_mount(NULL, "/dev", "devfs", 0);
  54     must_mount(NULL, "/sys", "twifs", MNT_RO);
  55     must_mount(NULL, "/task", "taskfs", MNT_RO);
  56
  57     if ((err = open("/dev/tty", 0)) < 0) {
  58         syslog(2, "fail to open tty (%d)\n", errno);
  59         return err;
  60     }
  61
  62     check(init_termios(err));
  63
  64     if ((err = dup(err)) < 0) {
  65         syslog(2, "fail to setup tty i/o (%d)\n", errno);
  66         return err;
  67     }
  68
  69     if ((err = symlink("/usr", "/mnt/lunaix-os/usr"))) {
  70         syslog(2, "symlink /usr:/mnt/lunaix-os/usr (%d)\n", errno);
  71         return err;
  72     }
  73
  74     pid_t pid;
  75     if (!(pid = fork())) {
  76         err = execve("/usr/bin/sh", NULL, NULL);
  77         printf("fail to execute (%d)\n", errno);
  78         _exit(err);
  79     }
  80
  81     waitpid(pid, &err, 0);
  82
  83     if (WEXITSTATUS(err)) {
  84         printf("shell exit abnormally (%d)", err);
  85     }
  86
  87     return err;
  88 }