sys_unix.c

/* Lua System: Unix specifics */

/*
 * Arguments: path (string)
 * Returns: [boolean]
 */
static int
sys_chroot (lua_State *L)
{
  const char *path = luaL_checkstring(L, 1);

  if (!chroot(path)) {
    lua_pushboolean(L, 1);
    return 1;
  }
  return sys_seterror(L, 0);
}

/*
 * Returns: [boolean]
 */
static int
sys_daemonize (lua_State *L)
{
  lua_pushboolean(L, 1);
  if (getppid() == 1)
    return 1;  /* already a daemon */

  switch (fork()) {
  case -1: goto err;
  case 0:  break;
  default: _exit(0);
  }
  if (setsid() == -1 || chdir("/") == -1)
    goto err;
  umask(0);
  /* standard files */
  {
    int fd = open("/dev/null", O_RDWR, 0);
    dup2(fd, 0);
    dup2(fd, 1);
    dup2(fd, 2);
    if (fd > 2) close(fd);
  }
  return 1;
 err:
  return sys_seterror(L, 0);
}

/*
 * Arguments: path (string), [permissions (number)]
 * Returns: [boolean]
 */
static int
sys_mkfifo (lua_State *L)
{
  const char *path = luaL_checkstring(L, 1);
  mode_t perm = (mode_t) luaL_optinteger(L, 2, SYS_FILE_PERMISSIONS);

  if (!mkfifo(path, perm)) {
    lua_pushboolean(L, 1);
    return 1;
  }
  return sys_seterror(L, 0);
}


#define UNIX_METHODS \
  {"chroot",		sys_chroot}, \
  {"daemonize",	sys_daemonize}, \
  {"mkfifo",		sys_mkfifo}