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     ({                                                                         \
  20         int err = 0;                                                           \
  21         if ((err = (statement)) < 0) {                                         \
  22             syslog(2, #statement " failed: %d", err);                          \
  23             _exit(1);                                                          \
  24         }                                                                      \
  25         err;                                                                   \
  26     })
  27
  28 int
  29 init_termios(int fd) {
  30     struct termios term;
  31
  32     check(tcgetattr(fd, &term));
  33
  34     term.c_lflag = ICANON | IEXTEN | ISIG | ECHO | ECHOE | ECHONL;
  35     term.c_iflag = ICRNL | IGNBRK;
  36     term.c_oflag = ONLCR | OPOST;
  37     term.c_cflag = CREAD | CLOCAL | CS8 | CPARENB;
  38     term.c_cc[VERASE] = 0x7f;
  39
  40     check(tcsetattr(fd, 0, &term));
  41
  42     return 0;
  43 }
  44
  45 const char* sh_argv[] = { "/usr/bin/sh", 0  };
  46 const char* sh_envp[] = {  0  };
  47
  48 int
  49 main(int argc, const char** argv)
  50 {
  51     mkdir("/dev");
  52     mkdir("/sys");
  53     mkdir("/task");
  54
  55     must_mount(NULL, "/dev", "devfs", 0);
  56     must_mount(NULL, "/sys", "twifs", MNT_RO);
  57     must_mount(NULL, "/task", "taskfs", MNT_RO);
  58
  59     int fd = check(open("/dev/tty", 0));
  60
  61     check(init_termios(fd));
  62
  63     check(dup(fd));
  64
  65     check(symlink("/usr", "/mnt/lunaix-os/usr"));
  66
  67     pid_t pid;
  68     int err = 0;
  69     if (!(pid = fork())) {
  70
  71
  72         err = execve(sh_argv[0], sh_argv, sh_envp);
  73         printf("fail to execute (%d)\n", errno);
  74         _exit(err);
  75     }
  76
  77     waitpid(pid, &err, 0);
  78
  79     if (WEXITSTATUS(err)) {
  80         printf("shell exit abnormally (%d)\n", err);
  81     }
  82
  83     printf("init exiting\n");
  84
  85     return err;
  86 }