+
+int ask(char *ret, const char *replies, const char *text, ...) {
+ assert(ret);
+ assert(replies);
+ assert(text);
+
+ for (;;) {
+ va_list ap;
+ char c;
+ int r;
+ bool need_nl = true;
+
+ va_start(ap, text);
+ vprintf(text, ap);
+ va_end(ap);
+
+ fflush(stdout);
+
+ if ((r = read_one_char(stdin, &c, &need_nl)) < 0) {
+
+ if (r == -EBADMSG) {
+ puts("Bad input, please try again.");
+ continue;
+ }
+
+ putchar('\n');
+ return r;
+ }
+
+ if (need_nl)
+ putchar('\n');
+
+ if (strchr(replies, c)) {
+ *ret = c;
+ return 0;
+ }
+
+ puts("Read unexpected character, please try again.");
+ }
+}
+
+int reset_terminal(int fd) {
+ struct termios termios;
+ int r = 0;
+
+ assert(fd >= 0);
+
+ /* Set terminal to some sane defaults */
+
+ if (tcgetattr(fd, &termios) < 0) {
+ r = -errno;
+ goto finish;
+ }
+
+ /* We only reset the stuff that matters to the software. How
+ * hardware is set up we don't touch assuming that somebody
+ * else will do that for us */
+
+ termios.c_iflag &= ~(IGNBRK | BRKINT | ISTRIP | INLCR | IGNCR | IUCLC);
+ termios.c_iflag |= ICRNL | IMAXBEL | IUTF8;
+ termios.c_oflag |= ONLCR;
+ termios.c_cflag |= CREAD;
+ termios.c_lflag = ISIG | ICANON | IEXTEN | ECHO | ECHOE | ECHOK | ECHOCTL | ECHOPRT | ECHOKE;
+
+ termios.c_cc[VINTR] = 03; /* ^C */
+ termios.c_cc[VQUIT] = 034; /* ^\ */
+ termios.c_cc[VERASE] = 0177;
+ termios.c_cc[VKILL] = 025; /* ^X */
+ termios.c_cc[VEOF] = 04; /* ^D */
+ termios.c_cc[VSTART] = 021; /* ^Q */
+ termios.c_cc[VSTOP] = 023; /* ^S */
+ termios.c_cc[VSUSP] = 032; /* ^Z */
+ termios.c_cc[VLNEXT] = 026; /* ^V */
+ termios.c_cc[VWERASE] = 027; /* ^W */
+ termios.c_cc[VREPRINT] = 022; /* ^R */
+ termios.c_cc[VEOL] = 0;
+ termios.c_cc[VEOL2] = 0;
+
+ termios.c_cc[VTIME] = 0;
+ termios.c_cc[VMIN] = 1;
+
+ if (tcsetattr(fd, TCSANOW, &termios) < 0)
+ r = -errno;
+
+finish:
+ /* Just in case, flush all crap out */
+ tcflush(fd, TCIOFLUSH);
+
+ return r;
+}
+
+int open_terminal(const char *name, int mode) {
+ int fd, r;
+
+ if ((fd = open(name, mode)) < 0)
+ return -errno;
+
+ if ((r = isatty(fd)) < 0) {
+ close_nointr_nofail(fd);
+ return -errno;
+ }
+
+ if (!r) {
+ close_nointr_nofail(fd);
+ return -ENOTTY;
+ }
+
+ return fd;
+}
+
+int flush_fd(int fd) {
+ struct pollfd pollfd;
+
+ zero(pollfd);
+ pollfd.fd = fd;
+ pollfd.events = POLLIN;
+
+ for (;;) {
+ char buf[1024];
+ ssize_t l;
+ int r;
+
+ if ((r = poll(&pollfd, 1, 0)) < 0) {
+
+ if (errno == EINTR)
+ continue;
+
+ return -errno;
+ }
+
+ if (r == 0)
+ return 0;
+
+ if ((l = read(fd, buf, sizeof(buf))) < 0) {
+
+ if (errno == EINTR)
+ continue;
+
+ if (errno == EAGAIN)
+ return 0;
+
+ return -errno;
+ }
+
+ if (l <= 0)
+ return 0;
+ }
+}
+
+int acquire_terminal(const char *name, bool fail, bool force) {
+ int fd = -1, notify = -1, r, wd;
+
+ assert(name);
+
+ /* We use inotify to be notified when the tty is closed. We
+ * create the watch before checking if we can actually acquire
+ * it, so that we don't lose any event.
+ *
+ * Note: strictly speaking this actually watches for the
+ * device being closed, it does *not* really watch whether a
+ * tty loses its controlling process. However, unless some
+ * rogue process uses TIOCNOTTY on /dev/tty *after* closing
+ * its tty otherwise this will not become a problem. As long
+ * as the administrator makes sure not configure any service
+ * on the same tty as an untrusted user this should not be a
+ * problem. (Which he probably should not do anyway.) */
+
+ if (!fail && !force) {
+ if ((notify = inotify_init1(IN_CLOEXEC)) < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ if ((wd = inotify_add_watch(notify, name, IN_CLOSE)) < 0) {
+ r = -errno;
+ goto fail;
+ }
+ }
+
+ for (;;) {
+ if ((r = flush_fd(notify)) < 0)
+ goto fail;
+
+ /* We pass here O_NOCTTY only so that we can check the return
+ * value TIOCSCTTY and have a reliable way to figure out if we
+ * successfully became the controlling process of the tty */
+ if ((fd = open_terminal(name, O_RDWR|O_NOCTTY)) < 0)
+ return -errno;
+
+ /* First, try to get the tty */
+ if ((r = ioctl(fd, TIOCSCTTY, force)) < 0 &&
+ (force || fail || errno != EPERM)) {
+ r = -errno;
+ goto fail;
+ }
+
+ if (r >= 0)
+ break;
+
+ assert(!fail);
+ assert(!force);
+ assert(notify >= 0);
+
+ for (;;) {
+ struct inotify_event e;
+ ssize_t l;
+
+ if ((l = read(notify, &e, sizeof(e))) != sizeof(e)) {
+
+ if (l < 0) {
+
+ if (errno == EINTR)
+ continue;
+
+ r = -errno;
+ } else
+ r = -EIO;
+
+ goto fail;
+ }
+
+ if (e.wd != wd || !(e.mask & IN_CLOSE)) {
+ r = -errno;
+ goto fail;
+ }
+
+ break;
+ }
+
+ /* We close the tty fd here since if the old session
+ * ended our handle will be dead. It's important that
+ * we do this after sleeping, so that we don't enter
+ * an endless loop. */
+ close_nointr_nofail(fd);
+ }
+
+ if (notify >= 0)
+ close_nointr_nofail(notify);
+
+ if ((r = reset_terminal(fd)) < 0)
+ log_warning("Failed to reset terminal: %s", strerror(-r));
+
+ return fd;
+
+fail:
+ if (fd >= 0)
+ close_nointr_nofail(fd);
+
+ if (notify >= 0)
+ close_nointr_nofail(notify);
+
+ return r;
+}
+
+int release_terminal(void) {
+ int r = 0, fd;
+
+ if ((fd = open("/dev/tty", O_RDWR)) < 0)
+ return -errno;
+
+ if (ioctl(fd, TIOCNOTTY) < 0)
+ r = -errno;
+
+ close_nointr_nofail(fd);
+ return r;
+}
+
+int ignore_signal(int sig) {
+ struct sigaction sa;
+
+ zero(sa);
+ sa.sa_handler = SIG_IGN;
+ sa.sa_flags = SA_RESTART;
+
+ return sigaction(sig, &sa, NULL);
+}
+
+int close_pipe(int p[]) {
+ int a = 0, b = 0;
+
+ assert(p);
+
+ if (p[0] >= 0) {
+ a = close_nointr(p[0]);
+ p[0] = -1;
+ }
+
+ if (p[1] >= 0) {
+ b = close_nointr(p[1]);
+ p[1] = -1;
+ }
+
+ return a < 0 ? a : b;
+}
+
+ssize_t loop_read(int fd, void *buf, size_t nbytes) {
+ uint8_t *p;
+ ssize_t n = 0;
+
+ assert(fd >= 0);
+ assert(buf);
+
+ p = buf;
+
+ while (nbytes > 0) {
+ ssize_t k;
+
+ if ((k = read(fd, p, nbytes)) <= 0) {
+
+ if (errno == EINTR)
+ continue;
+
+ if (errno == EAGAIN) {
+ struct pollfd pollfd;
+
+ zero(pollfd);
+ pollfd.fd = fd;
+ pollfd.events = POLLIN;
+
+ if (poll(&pollfd, 1, -1) < 0) {
+ if (errno == EINTR)
+ continue;
+
+ return n > 0 ? n : -errno;
+ }
+
+ if (pollfd.revents != POLLIN)
+ return n > 0 ? n : -EIO;
+
+ continue;
+ }
+
+ return n > 0 ? n : (k < 0 ? -errno : 0);
+ }
+
+ p += k;
+ nbytes -= k;
+ n += k;
+ }
+
+ return n;
+}
+
+int path_is_mount_point(const char *t) {
+ struct stat a, b;
+ char *copy;
+
+ if (lstat(t, &a) < 0) {
+
+ if (errno == ENOENT)
+ return 0;
+
+ return -errno;
+ }
+
+ if (!(copy = strdup(t)))
+ return -ENOMEM;
+
+ if (lstat(dirname(copy), &b) < 0) {
+ free(copy);
+ return -errno;
+ }
+
+ free(copy);
+
+ return a.st_dev != b.st_dev;
+}
+
+static const char *const ioprio_class_table[] = {
+ [IOPRIO_CLASS_NONE] = "none",
+ [IOPRIO_CLASS_RT] = "realtime",
+ [IOPRIO_CLASS_BE] = "best-effort",
+ [IOPRIO_CLASS_IDLE] = "idle"
+};
+
+DEFINE_STRING_TABLE_LOOKUP(ioprio_class, int);
+
+static const char *const sigchld_code_table[] = {
+ [CLD_EXITED] = "exited",
+ [CLD_KILLED] = "killed",
+ [CLD_DUMPED] = "dumped",
+ [CLD_TRAPPED] = "trapped",
+ [CLD_STOPPED] = "stopped",
+ [CLD_CONTINUED] = "continued",
+};
+
+DEFINE_STRING_TABLE_LOOKUP(sigchld_code, int);
+
+static const char *const log_facility_table[LOG_NFACILITIES] = {
+ [LOG_FAC(LOG_KERN)] = "kern",
+ [LOG_FAC(LOG_USER)] = "user",
+ [LOG_FAC(LOG_MAIL)] = "mail",
+ [LOG_FAC(LOG_DAEMON)] = "daemon",
+ [LOG_FAC(LOG_AUTH)] = "auth",
+ [LOG_FAC(LOG_SYSLOG)] = "syslog",
+ [LOG_FAC(LOG_LPR)] = "lpr",
+ [LOG_FAC(LOG_NEWS)] = "news",
+ [LOG_FAC(LOG_UUCP)] = "uucp",
+ [LOG_FAC(LOG_CRON)] = "cron",
+ [LOG_FAC(LOG_AUTHPRIV)] = "authpriv",
+ [LOG_FAC(LOG_FTP)] = "ftp",
+ [LOG_FAC(LOG_LOCAL0)] = "local0",
+ [LOG_FAC(LOG_LOCAL1)] = "local1",
+ [LOG_FAC(LOG_LOCAL2)] = "local2",
+ [LOG_FAC(LOG_LOCAL3)] = "local3",
+ [LOG_FAC(LOG_LOCAL4)] = "local4",
+ [LOG_FAC(LOG_LOCAL5)] = "local5",
+ [LOG_FAC(LOG_LOCAL6)] = "local6",
+ [LOG_FAC(LOG_LOCAL7)] = "local7"
+};
+
+DEFINE_STRING_TABLE_LOOKUP(log_facility, int);
+
+static const char *const log_level_table[] = {
+ [LOG_EMERG] = "emerg",
+ [LOG_ALERT] = "alert",
+ [LOG_CRIT] = "crit",
+ [LOG_ERR] = "err",
+ [LOG_WARNING] = "warning",
+ [LOG_NOTICE] = "notice",
+ [LOG_INFO] = "info",
+ [LOG_DEBUG] = "debug"
+};
+
+DEFINE_STRING_TABLE_LOOKUP(log_level, int);
+
+static const char* const sched_policy_table[] = {
+ [SCHED_OTHER] = "other",
+ [SCHED_BATCH] = "batch",
+ [SCHED_IDLE] = "idle",
+ [SCHED_FIFO] = "fifo",
+ [SCHED_RR] = "rr"
+};
+
+DEFINE_STRING_TABLE_LOOKUP(sched_policy, int);
+
+static const char* const rlimit_table[] = {
+ [RLIMIT_CPU] = "LimitCPU",
+ [RLIMIT_FSIZE] = "LimitFSIZE",
+ [RLIMIT_DATA] = "LimitDATA",
+ [RLIMIT_STACK] = "LimitSTACK",
+ [RLIMIT_CORE] = "LimitCORE",
+ [RLIMIT_RSS] = "LimitRSS",
+ [RLIMIT_NOFILE] = "LimitNOFILE",
+ [RLIMIT_AS] = "LimitAS",
+ [RLIMIT_NPROC] = "LimitNPROC",
+ [RLIMIT_MEMLOCK] = "LimitMEMLOCK",
+ [RLIMIT_LOCKS] = "LimitLOCKS",
+ [RLIMIT_SIGPENDING] = "LimitSIGPENDING",
+ [RLIMIT_MSGQUEUE] = "LimitMSGQUEUE",
+ [RLIMIT_NICE] = "LimitNICE",
+ [RLIMIT_RTPRIO] = "LimitRTPRIO",
+ [RLIMIT_RTTIME] = "LimitRTTIME"
+};
+
+DEFINE_STRING_TABLE_LOOKUP(rlimit, int);