Merge pull request #12378 from rbalint/vt-kbd-reset-check

VT kbd reset check
int get_ctty_devnr(pid_t pid, dev_t *d) {
        int r;
        _cleanup_free_ char *line = NULL;
        const char *p;
        unsigned long ttynr;

        assert(pid >= 0);

        p = procfs_file_alloca(pid, "stat");
        r = read_one_line_file(p, &line);
        if (r < 0)
                return r;

        p = strrchr(line, ')');
        if (!p)
                return -EIO;

        p++;

        if (sscanf(p, " "
                   "%*c "  /* state */
                   "%*d "  /* ppid */
                   "%*d "  /* pgrp */
                   "%*d "  /* session */
                   "%lu ", /* ttynr */
                   &ttynr) != 1)
                return -EIO;

        if (major(ttynr) == 0 && minor(ttynr) == 0)
                return -ENXIO;

        if (d)
                *d = (dev_t) ttynr;

        return 0;
}

int get_ctty_devnr(pid_t pid, dev_t *d) {
        int r;
        _cleanup_free_ char *line = NULL;
        const char *p;
        unsigned long ttynr;

        assert(pid >= 0);

        p = procfs_file_alloca(pid, "stat");
        r = read_one_line_file(p, &line);
        if (r < 0)
                return r;

        p = strrchr(line, ')');
        if (!p)
                return -EIO;

        p++;

        if (sscanf(p, " "
                   "%*c "  /* state */
                   "%*d "  /* ppid */
                   "%*d "  /* pgrp */
                   "%*d "  /* session */
                   "%lu ", /* ttynr */
                   &ttynr) != 1)
                return -EIO;

        if (major(ttynr) == 0 && minor(ttynr) == 0)
                return -ENXIO;

        if (d)
                *d = (dev_t) ttynr;

        return 0;
}
