| /* SPDX-License-Identifier: LGPL-2.1-or-later */ |
| |
| #include <errno.h> |
| #include <fcntl.h> |
| #include <limits.h> |
| #include <linux/kd.h> |
| #include <linux/tiocl.h> |
| #include <linux/vt.h> |
| #include <poll.h> |
| #include <signal.h> |
| #include <stdarg.h> |
| #include <stddef.h> |
| #include <stdlib.h> |
| #include <sys/inotify.h> |
| #include <sys/ioctl.h> |
| #include <sys/sysmacros.h> |
| #include <sys/time.h> |
| #include <sys/types.h> |
| #include <sys/utsname.h> |
| #include <termios.h> |
| #include <unistd.h> |
| |
| #include "alloc-util.h" |
| #include "def.h" |
| #include "env-util.h" |
| #include "fd-util.h" |
| #include "fileio.h" |
| #include "fs-util.h" |
| #include "io-util.h" |
| #include "log.h" |
| #include "macro.h" |
| #include "namespace-util.h" |
| #include "parse-util.h" |
| #include "path-util.h" |
| #include "proc-cmdline.h" |
| #include "process-util.h" |
| #include "socket-util.h" |
| #include "stat-util.h" |
| #include "stdio-util.h" |
| #include "string-util.h" |
| #include "strv.h" |
| #include "terminal-util.h" |
| #include "time-util.h" |
| #include "user-util.h" |
| #include "util.h" |
| |
| static volatile unsigned cached_columns = 0; |
| static volatile unsigned cached_lines = 0; |
| |
| static volatile int cached_on_tty = -1; |
| static volatile int cached_color_mode = _COLOR_INVALID; |
| static volatile int cached_underline_enabled = -1; |
| |
| int chvt(int vt) { |
| _cleanup_close_ int fd = -1; |
| |
| /* Switch to the specified vt number. If the VT is specified <= 0 switch to the VT the kernel log messages go, |
| * if that's configured. */ |
| |
| fd = open_terminal("/dev/tty0", O_RDWR|O_NOCTTY|O_CLOEXEC|O_NONBLOCK); |
| if (fd < 0) |
| return -errno; |
| |
| if (vt <= 0) { |
| int tiocl[2] = { |
| TIOCL_GETKMSGREDIRECT, |
| 0 |
| }; |
| |
| if (ioctl(fd, TIOCLINUX, tiocl) < 0) |
| return -errno; |
| |
| vt = tiocl[0] <= 0 ? 1 : tiocl[0]; |
| } |
| |
| if (ioctl(fd, VT_ACTIVATE, vt) < 0) |
| return -errno; |
| |
| return 0; |
| } |
| |
| int read_one_char(FILE *f, char *ret, usec_t t, bool *need_nl) { |
| _cleanup_free_ char *line = NULL; |
| struct termios old_termios; |
| int r, fd; |
| |
| assert(f); |
| assert(ret); |
| |
| /* If this is a terminal, then switch canonical mode off, so that we can read a single |
| * character. (Note that fmemopen() streams do not have an fd associated with them, let's handle that |
| * nicely.) */ |
| fd = fileno(f); |
| if (fd >= 0 && tcgetattr(fd, &old_termios) >= 0) { |
| struct termios new_termios = old_termios; |
| |
| new_termios.c_lflag &= ~ICANON; |
| new_termios.c_cc[VMIN] = 1; |
| new_termios.c_cc[VTIME] = 0; |
| |
| if (tcsetattr(fd, TCSADRAIN, &new_termios) >= 0) { |
| char c; |
| |
| if (t != USEC_INFINITY) { |
| if (fd_wait_for_event(fd, POLLIN, t) <= 0) { |
| (void) tcsetattr(fd, TCSADRAIN, &old_termios); |
| return -ETIMEDOUT; |
| } |
| } |
| |
| r = safe_fgetc(f, &c); |
| (void) tcsetattr(fd, TCSADRAIN, &old_termios); |
| if (r < 0) |
| return r; |
| if (r == 0) |
| return -EIO; |
| |
| if (need_nl) |
| *need_nl = c != '\n'; |
| |
| *ret = c; |
| return 0; |
| } |
| } |
| |
| if (t != USEC_INFINITY && fd > 0) { |
| /* Let's wait the specified amount of time for input. When we have no fd we skip this, under |
| * the assumption that this is an fmemopen() stream or so where waiting doesn't make sense |
| * anyway, as the data is either already in the stream or cannot possible be placed there |
| * while we access the stream */ |
| |
| if (fd_wait_for_event(fd, POLLIN, t) <= 0) |
| return -ETIMEDOUT; |
| } |
| |
| /* If this is not a terminal, then read a full line instead */ |
| |
| r = read_line(f, 16, &line); /* longer than necessary, to eat up UTF-8 chars/vt100 key sequences */ |
| if (r < 0) |
| return r; |
| if (r == 0) |
| return -EIO; |
| |
| if (strlen(line) != 1) |
| return -EBADMSG; |
| |
| if (need_nl) |
| *need_nl = false; |
| |
| *ret = line[0]; |
| return 0; |
| } |
| |
| #define DEFAULT_ASK_REFRESH_USEC (2*USEC_PER_SEC) |
| |
| int ask_char(char *ret, const char *replies, const char *fmt, ...) { |
| int r; |
| |
| assert(ret); |
| assert(replies); |
| assert(fmt); |
| |
| for (;;) { |
| va_list ap; |
| char c; |
| bool need_nl = true; |
| |
| fputs(ansi_highlight(), stdout); |
| |
| putchar('\r'); |
| |
| va_start(ap, fmt); |
| vprintf(fmt, ap); |
| va_end(ap); |
| |
| fputs(ansi_normal(), stdout); |
| |
| fflush(stdout); |
| |
| r = read_one_char(stdin, &c, DEFAULT_ASK_REFRESH_USEC, &need_nl); |
| if (r < 0) { |
| |
| if (r == -ETIMEDOUT) |
| continue; |
| |
| 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 ask_string(char **ret, const char *text, ...) { |
| _cleanup_free_ char *line = NULL; |
| va_list ap; |
| int r; |
| |
| assert(ret); |
| assert(text); |
| |
| fputs(ansi_highlight(), stdout); |
| |
| va_start(ap, text); |
| vprintf(text, ap); |
| va_end(ap); |
| |
| fputs(ansi_normal(), stdout); |
| |
| fflush(stdout); |
| |
| r = read_line(stdin, LONG_LINE_MAX, &line); |
| if (r < 0) |
| return r; |
| if (r == 0) |
| return -EIO; |
| |
| *ret = TAKE_PTR(line); |
| return 0; |
| } |
| |
| int reset_terminal_fd(int fd, bool switch_to_text) { |
| struct termios termios; |
| int r = 0; |
| |
| /* Set terminal to some sane defaults */ |
| |
| assert(fd >= 0); |
| |
| if (isatty(fd) < 1) |
| return log_debug_errno(errno, "Asked to reset a terminal that actually isn't a terminal: %m"); |
| |
| /* We leave locked terminal attributes untouched, so that Plymouth may set whatever it wants to set, |
| * and we don't interfere with that. */ |
| |
| /* Disable exclusive mode, just in case */ |
| if (ioctl(fd, TIOCNXCL) < 0) |
| log_debug_errno(errno, "TIOCNXCL ioctl failed on TTY, ignoring: %m"); |
| |
| /* Switch to text mode */ |
| if (switch_to_text) |
| if (ioctl(fd, KDSETMODE, KD_TEXT) < 0) |
| log_debug_errno(errno, "KDSETMODE ioctl for switching to text mode failed on TTY, ignoring: %m"); |
| |
| |
| /* Set default keyboard mode */ |
| (void) vt_reset_keyboard(fd); |
| |
| if (tcgetattr(fd, &termios) < 0) { |
| r = log_debug_errno(errno, "Failed to get terminal parameters: %m"); |
| 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 */ |
| (void) tcflush(fd, TCIOFLUSH); |
| |
| return r; |
| } |
| |
| int reset_terminal(const char *name) { |
| _cleanup_close_ int fd = -1; |
| |
| /* We open the terminal with O_NONBLOCK here, to ensure we |
| * don't block on carrier if this is a terminal with carrier |
| * configured. */ |
| |
| fd = open_terminal(name, O_RDWR|O_NOCTTY|O_CLOEXEC|O_NONBLOCK); |
| if (fd < 0) |
| return fd; |
| |
| return reset_terminal_fd(fd, true); |
| } |
| |
| int open_terminal(const char *name, int mode) { |
| _cleanup_close_ int fd = -1; |
| unsigned c = 0; |
| |
| /* |
| * If a TTY is in the process of being closed opening it might cause EIO. This is horribly awful, but |
| * unlikely to be changed in the kernel. Hence we work around this problem by retrying a couple of |
| * times. |
| * |
| * https://bugs.launchpad.net/ubuntu/+source/linux/+bug/554172/comments/245 |
| */ |
| |
| if (mode & O_CREAT) |
| return -EINVAL; |
| |
| for (;;) { |
| fd = open(name, mode, 0); |
| if (fd >= 0) |
| break; |
| |
| if (errno != EIO) |
| return -errno; |
| |
| /* Max 1s in total */ |
| if (c >= 20) |
| return -errno; |
| |
| (void) usleep(50 * USEC_PER_MSEC); |
| c++; |
| } |
| |
| if (isatty(fd) < 1) |
| return negative_errno(); |
| |
| return TAKE_FD(fd); |
| } |
| |
| int acquire_terminal( |
| const char *name, |
| AcquireTerminalFlags flags, |
| usec_t timeout) { |
| |
| _cleanup_close_ int notify = -1, fd = -1; |
| usec_t ts = USEC_INFINITY; |
| int r, wd = -1; |
| |
| assert(name); |
| assert(IN_SET(flags & ~ACQUIRE_TERMINAL_PERMISSIVE, ACQUIRE_TERMINAL_TRY, ACQUIRE_TERMINAL_FORCE, ACQUIRE_TERMINAL_WAIT)); |
| |
| /* 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 to |
| * not configure any service on the same tty as an untrusted user this should not be a problem. (Which they |
| * probably should not do anyway.) */ |
| |
| if ((flags & ~ACQUIRE_TERMINAL_PERMISSIVE) == ACQUIRE_TERMINAL_WAIT) { |
| notify = inotify_init1(IN_CLOEXEC | (timeout != USEC_INFINITY ? IN_NONBLOCK : 0)); |
| if (notify < 0) |
| return -errno; |
| |
| wd = inotify_add_watch(notify, name, IN_CLOSE); |
| if (wd < 0) |
| return -errno; |
| |
| if (timeout != USEC_INFINITY) |
| ts = now(CLOCK_MONOTONIC); |
| } |
| |
| for (;;) { |
| struct sigaction sa_old, sa_new = { |
| .sa_handler = SIG_IGN, |
| .sa_flags = SA_RESTART, |
| }; |
| |
| if (notify >= 0) { |
| r = flush_fd(notify); |
| if (r < 0) |
| return r; |
| } |
| |
| /* 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 */ |
| fd = open_terminal(name, O_RDWR|O_NOCTTY|O_CLOEXEC); |
| if (fd < 0) |
| return fd; |
| |
| /* Temporarily ignore SIGHUP, so that we don't get SIGHUP'ed if we already own the tty. */ |
| assert_se(sigaction(SIGHUP, &sa_new, &sa_old) == 0); |
| |
| /* First, try to get the tty */ |
| r = ioctl(fd, TIOCSCTTY, |
| (flags & ~ACQUIRE_TERMINAL_PERMISSIVE) == ACQUIRE_TERMINAL_FORCE) < 0 ? -errno : 0; |
| |
| /* Reset signal handler to old value */ |
| assert_se(sigaction(SIGHUP, &sa_old, NULL) == 0); |
| |
| /* Success? Exit the loop now! */ |
| if (r >= 0) |
| break; |
| |
| /* Any failure besides -EPERM? Fail, regardless of the mode. */ |
| if (r != -EPERM) |
| return r; |
| |
| if (flags & ACQUIRE_TERMINAL_PERMISSIVE) /* If we are in permissive mode, then EPERM is fine, turn this |
| * into a success. Note that EPERM is also returned if we |
| * already are the owner of the TTY. */ |
| break; |
| |
| if (flags != ACQUIRE_TERMINAL_WAIT) /* If we are in TRY or FORCE mode, then propagate EPERM as EPERM */ |
| return r; |
| |
| assert(notify >= 0); |
| assert(wd >= 0); |
| |
| for (;;) { |
| union inotify_event_buffer buffer; |
| struct inotify_event *e; |
| ssize_t l; |
| |
| if (timeout != USEC_INFINITY) { |
| usec_t n; |
| |
| assert(ts != USEC_INFINITY); |
| |
| n = usec_sub_unsigned(now(CLOCK_MONOTONIC), ts); |
| if (n >= timeout) |
| return -ETIMEDOUT; |
| |
| r = fd_wait_for_event(notify, POLLIN, usec_sub_unsigned(timeout, n)); |
| if (r < 0) |
| return r; |
| if (r == 0) |
| return -ETIMEDOUT; |
| } |
| |
| l = read(notify, &buffer, sizeof(buffer)); |
| if (l < 0) { |
| if (IN_SET(errno, EINTR, EAGAIN)) |
| continue; |
| |
| return -errno; |
| } |
| |
| FOREACH_INOTIFY_EVENT(e, buffer, l) { |
| if (e->mask & IN_Q_OVERFLOW) /* If we hit an inotify queue overflow, simply check if the terminal is up for grabs now. */ |
| break; |
| |
| if (e->wd != wd || !(e->mask & IN_CLOSE)) /* Safety checks */ |
| return -EIO; |
| } |
| |
| 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. */ |
| fd = safe_close(fd); |
| } |
| |
| return TAKE_FD(fd); |
| } |
| |
| int release_terminal(void) { |
| static const struct sigaction sa_new = { |
| .sa_handler = SIG_IGN, |
| .sa_flags = SA_RESTART, |
| }; |
| |
| _cleanup_close_ int fd = -1; |
| struct sigaction sa_old; |
| int r; |
| |
| fd = open("/dev/tty", O_RDWR|O_NOCTTY|O_CLOEXEC|O_NONBLOCK); |
| if (fd < 0) |
| return -errno; |
| |
| /* Temporarily ignore SIGHUP, so that we don't get SIGHUP'ed |
| * by our own TIOCNOTTY */ |
| assert_se(sigaction(SIGHUP, &sa_new, &sa_old) == 0); |
| |
| r = ioctl(fd, TIOCNOTTY) < 0 ? -errno : 0; |
| |
| assert_se(sigaction(SIGHUP, &sa_old, NULL) == 0); |
| |
| return r; |
| } |
| |
| int terminal_vhangup_fd(int fd) { |
| assert(fd >= 0); |
| |
| if (ioctl(fd, TIOCVHANGUP) < 0) |
| return -errno; |
| |
| return 0; |
| } |
| |
| int terminal_vhangup(const char *name) { |
| _cleanup_close_ int fd = -1; |
| |
| fd = open_terminal(name, O_RDWR|O_NOCTTY|O_CLOEXEC|O_NONBLOCK); |
| if (fd < 0) |
| return fd; |
| |
| return terminal_vhangup_fd(fd); |
| } |
| |
| int vt_disallocate(const char *name) { |
| const char *e; |
| int r; |
| |
| /* Deallocate the VT if possible. If not possible |
| * (i.e. because it is the active one), at least clear it |
| * entirely (including the scrollback buffer). */ |
| |
| e = path_startswith(name, "/dev/"); |
| if (!e) |
| return -EINVAL; |
| |
| if (tty_is_vc(name)) { |
| _cleanup_close_ int fd = -1; |
| unsigned u; |
| const char *n; |
| |
| n = startswith(e, "tty"); |
| if (!n) |
| return -EINVAL; |
| |
| r = safe_atou(n, &u); |
| if (r < 0) |
| return r; |
| |
| if (u <= 0) |
| return -EINVAL; |
| |
| /* Try to deallocate */ |
| fd = open_terminal("/dev/tty0", O_RDWR|O_NOCTTY|O_CLOEXEC|O_NONBLOCK); |
| if (fd < 0) |
| return fd; |
| |
| r = ioctl(fd, VT_DISALLOCATE, u); |
| if (r >= 0) |
| return 0; |
| if (errno != EBUSY) |
| return -errno; |
| } |
| |
| /* So this is not a VT (in which case we cannot deallocate it), |
| * or we failed to deallocate. Let's at least clear the screen. */ |
| |
| _cleanup_close_ int fd2 = open_terminal(name, O_RDWR|O_NOCTTY|O_CLOEXEC); |
| if (fd2 < 0) |
| return fd2; |
| |
| (void) loop_write(fd2, |
| "\033[r" /* clear scrolling region */ |
| "\033[H" /* move home */ |
| "\033[3J", /* clear screen including scrollback, requires Linux 2.6.40 */ |
| 10, false); |
| return 0; |
| } |
| |
| int make_console_stdio(void) { |
| int fd, r; |
| |
| /* Make /dev/console the controlling terminal and stdin/stdout/stderr, if we can. If we can't use |
| * /dev/null instead. This is particularly useful if /dev/console is turned off, e.g. if console=null |
| * is specified on the kernel command line. */ |
| |
| fd = acquire_terminal("/dev/console", ACQUIRE_TERMINAL_FORCE|ACQUIRE_TERMINAL_PERMISSIVE, USEC_INFINITY); |
| if (fd < 0) { |
| log_warning_errno(fd, "Failed to acquire terminal, using /dev/null stdin/stdout/stderr instead: %m"); |
| |
| r = make_null_stdio(); |
| if (r < 0) |
| return log_error_errno(r, "Failed to make /dev/null stdin/stdout/stderr: %m"); |
| |
| } else { |
| r = reset_terminal_fd(fd, true); |
| if (r < 0) |
| log_warning_errno(r, "Failed to reset terminal, ignoring: %m"); |
| |
| r = rearrange_stdio(fd, fd, fd); /* This invalidates 'fd' both on success and on failure. */ |
| if (r < 0) |
| return log_error_errno(r, "Failed to make terminal stdin/stdout/stderr: %m"); |
| } |
| |
| reset_terminal_feature_caches(); |
| return 0; |
| } |
| |
| bool tty_is_vc(const char *tty) { |
| assert(tty); |
| |
| return vtnr_from_tty(tty) >= 0; |
| } |
| |
| bool tty_is_console(const char *tty) { |
| assert(tty); |
| |
| return streq(skip_dev_prefix(tty), "console"); |
| } |
| |
| int vtnr_from_tty(const char *tty) { |
| int i, r; |
| |
| assert(tty); |
| |
| tty = skip_dev_prefix(tty); |
| |
| if (!startswith(tty, "tty") ) |
| return -EINVAL; |
| |
| if (tty[3] < '0' || tty[3] > '9') |
| return -EINVAL; |
| |
| r = safe_atoi(tty+3, &i); |
| if (r < 0) |
| return r; |
| |
| if (i < 0 || i > 63) |
| return -EINVAL; |
| |
| return i; |
| } |
| |
| int resolve_dev_console(char **ret) { |
| _cleanup_free_ char *active = NULL; |
| char *tty; |
| int r; |
| |
| assert(ret); |
| |
| /* Resolve where /dev/console is pointing to, if /sys is actually ours (i.e. not read-only-mounted which is a |
| * sign for container setups) */ |
| |
| if (path_is_read_only_fs("/sys") > 0) |
| return -ENOMEDIUM; |
| |
| r = read_one_line_file("/sys/class/tty/console/active", &active); |
| if (r < 0) |
| return r; |
| |
| /* If multiple log outputs are configured the last one is what /dev/console points to */ |
| tty = strrchr(active, ' '); |
| if (tty) |
| tty++; |
| else |
| tty = active; |
| |
| if (streq(tty, "tty0")) { |
| active = mfree(active); |
| |
| /* Get the active VC (e.g. tty1) */ |
| r = read_one_line_file("/sys/class/tty/tty0/active", &active); |
| if (r < 0) |
| return r; |
| |
| tty = active; |
| } |
| |
| if (tty == active) |
| *ret = TAKE_PTR(active); |
| else { |
| char *tmp; |
| |
| tmp = strdup(tty); |
| if (!tmp) |
| return -ENOMEM; |
| |
| *ret = tmp; |
| } |
| |
| return 0; |
| } |
| |
| int get_kernel_consoles(char ***ret) { |
| _cleanup_strv_free_ char **l = NULL; |
| _cleanup_free_ char *line = NULL; |
| const char *p; |
| int r; |
| |
| assert(ret); |
| |
| /* If /sys is mounted read-only this means we are running in some kind of container environment. In that |
| * case /sys would reflect the host system, not us, hence ignore the data we can read from it. */ |
| if (path_is_read_only_fs("/sys") > 0) |
| goto fallback; |
| |
| r = read_one_line_file("/sys/class/tty/console/active", &line); |
| if (r < 0) |
| return r; |
| |
| p = line; |
| for (;;) { |
| _cleanup_free_ char *tty = NULL, *path = NULL; |
| |
| r = extract_first_word(&p, &tty, NULL, 0); |
| if (r < 0) |
| return r; |
| if (r == 0) |
| break; |
| |
| if (streq(tty, "tty0")) { |
| tty = mfree(tty); |
| r = read_one_line_file("/sys/class/tty/tty0/active", &tty); |
| if (r < 0) |
| return r; |
| } |
| |
| path = path_join("/dev", tty); |
| if (!path) |
| return -ENOMEM; |
| |
| if (access(path, F_OK) < 0) { |
| log_debug_errno(errno, "Console device %s is not accessible, skipping: %m", path); |
| continue; |
| } |
| |
| r = strv_consume(&l, TAKE_PTR(path)); |
| if (r < 0) |
| return r; |
| } |
| |
| if (strv_isempty(l)) { |
| log_debug("No devices found for system console"); |
| goto fallback; |
| } |
| |
| *ret = TAKE_PTR(l); |
| |
| return 0; |
| |
| fallback: |
| r = strv_extend(&l, "/dev/console"); |
| if (r < 0) |
| return r; |
| |
| *ret = TAKE_PTR(l); |
| |
| return 0; |
| } |
| |
| bool tty_is_vc_resolve(const char *tty) { |
| _cleanup_free_ char *resolved = NULL; |
| |
| assert(tty); |
| |
| tty = skip_dev_prefix(tty); |
| |
| if (streq(tty, "console")) { |
| if (resolve_dev_console(&resolved) < 0) |
| return false; |
| |
| tty = resolved; |
| } |
| |
| return tty_is_vc(tty); |
| } |
| |
| const char *default_term_for_tty(const char *tty) { |
| return tty && tty_is_vc_resolve(tty) ? "linux" : "vt220"; |
| } |
| |
| int fd_columns(int fd) { |
| struct winsize ws = {}; |
| |
| if (fd < 0) |
| return -EBADF; |
| |
| if (ioctl(fd, TIOCGWINSZ, &ws) < 0) |
| return -errno; |
| |
| if (ws.ws_col <= 0) |
| return -EIO; |
| |
| return ws.ws_col; |
| } |
| |
| unsigned columns(void) { |
| const char *e; |
| int c; |
| |
| if (cached_columns > 0) |
| return cached_columns; |
| |
| c = 0; |
| e = getenv("COLUMNS"); |
| if (e) |
| (void) safe_atoi(e, &c); |
| |
| if (c <= 0 || c > USHRT_MAX) { |
| c = fd_columns(STDOUT_FILENO); |
| if (c <= 0) |
| c = 80; |
| } |
| |
| cached_columns = c; |
| return cached_columns; |
| } |
| |
| int fd_lines(int fd) { |
| struct winsize ws = {}; |
| |
| if (fd < 0) |
| return -EBADF; |
| |
| if (ioctl(fd, TIOCGWINSZ, &ws) < 0) |
| return -errno; |
| |
| if (ws.ws_row <= 0) |
| return -EIO; |
| |
| return ws.ws_row; |
| } |
| |
| unsigned lines(void) { |
| const char *e; |
| int l; |
| |
| if (cached_lines > 0) |
| return cached_lines; |
| |
| l = 0; |
| e = getenv("LINES"); |
| if (e) |
| (void) safe_atoi(e, &l); |
| |
| if (l <= 0 || l > USHRT_MAX) { |
| l = fd_lines(STDOUT_FILENO); |
| if (l <= 0) |
| l = 24; |
| } |
| |
| cached_lines = l; |
| return cached_lines; |
| } |
| |
| /* intended to be used as a SIGWINCH sighandler */ |
| void columns_lines_cache_reset(int signum) { |
| cached_columns = 0; |
| cached_lines = 0; |
| } |
| |
| void reset_terminal_feature_caches(void) { |
| cached_columns = 0; |
| cached_lines = 0; |
| |
| cached_color_mode = _COLOR_INVALID; |
| cached_underline_enabled = -1; |
| cached_on_tty = -1; |
| } |
| |
| bool on_tty(void) { |
| |
| /* We check both stdout and stderr, so that situations where pipes on the shell are used are reliably |
| * recognized, regardless if only the output or the errors are piped to some place. Since on_tty() is generally |
| * used to default to a safer, non-interactive, non-color mode of operation it's probably good to be defensive |
| * here, and check for both. Note that we don't check for STDIN_FILENO, because it should fine to use fancy |
| * terminal functionality when outputting stuff, even if the input is piped to us. */ |
| |
| if (cached_on_tty < 0) |
| cached_on_tty = |
| isatty(STDOUT_FILENO) > 0 && |
| isatty(STDERR_FILENO) > 0; |
| |
| return cached_on_tty; |
| } |
| |
| int getttyname_malloc(int fd, char **ret) { |
| char path[PATH_MAX], *c; /* PATH_MAX is counted *with* the trailing NUL byte */ |
| int r; |
| |
| assert(fd >= 0); |
| assert(ret); |
| |
| r = ttyname_r(fd, path, sizeof path); /* positive error */ |
| assert(r >= 0); |
| if (r == ERANGE) |
| return -ENAMETOOLONG; |
| if (r > 0) |
| return -r; |
| |
| c = strdup(skip_dev_prefix(path)); |
| if (!c) |
| return -ENOMEM; |
| |
| *ret = c; |
| return 0; |
| } |
| |
| int getttyname_harder(int fd, char **ret) { |
| _cleanup_free_ char *s = NULL; |
| int r; |
| |
| r = getttyname_malloc(fd, &s); |
| if (r < 0) |
| return r; |
| |
| if (streq(s, "tty")) |
| return get_ctty(0, NULL, ret); |
| |
| *ret = TAKE_PTR(s); |
| 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; |
| } |
| |
| int get_ctty(pid_t pid, dev_t *ret_devnr, char **ret) { |
| char pty[STRLEN("/dev/pts/") + DECIMAL_STR_MAX(dev_t) + 1]; |
| _cleanup_free_ char *buf = NULL; |
| const char *fn = NULL, *w; |
| dev_t devnr; |
| int r; |
| |
| r = get_ctty_devnr(pid, &devnr); |
| if (r < 0) |
| return r; |
| |
| r = device_path_make_canonical(S_IFCHR, devnr, &buf); |
| if (r < 0) { |
| struct stat st; |
| |
| if (r != -ENOENT) /* No symlink for this in /dev/char/? */ |
| return r; |
| |
| /* Maybe this is PTY? PTY devices are not listed in /dev/char/, as they don't follow the |
| * Linux device model and hence device_path_make_canonical() doesn't work for them. Let's |
| * assume this is a PTY for a moment, and check if the device node this would then map to in |
| * /dev/pts/ matches the one we are looking for. This way we don't have to hardcode the major |
| * number (which is 136 btw), but we still rely on the fact that PTY numbers map directly to |
| * the minor number of the pty. */ |
| xsprintf(pty, "/dev/pts/%u", minor(devnr)); |
| |
| if (stat(pty, &st) < 0) { |
| if (errno != ENOENT) |
| return -errno; |
| |
| } else if (S_ISCHR(st.st_mode) && devnr == st.st_rdev) /* Bingo! */ |
| fn = pty; |
| |
| if (!fn) { |
| /* Doesn't exist, or not a PTY? Probably something similar to the PTYs which have no |
| * symlink in /dev/char/. Let's return something vaguely useful. */ |
| r = device_path_make_major_minor(S_IFCHR, devnr, &buf); |
| if (r < 0) |
| return r; |
| |
| fn = buf; |
| } |
| } else |
| fn = buf; |
| |
| w = path_startswith(fn, "/dev/"); |
| if (!w) |
| return -EINVAL; |
| |
| if (ret) { |
| _cleanup_free_ char *b = NULL; |
| |
| b = strdup(w); |
| if (!b) |
| return -ENOMEM; |
| |
| *ret = TAKE_PTR(b); |
| } |
| |
| if (ret_devnr) |
| *ret_devnr = devnr; |
| |
| return 0; |
| } |
| |
| int ptsname_malloc(int fd, char **ret) { |
| size_t l = 100; |
| |
| assert(fd >= 0); |
| assert(ret); |
| |
| for (;;) { |
| char *c; |
| |
| c = new(char, l); |
| if (!c) |
| return -ENOMEM; |
| |
| if (ptsname_r(fd, c, l) == 0) { |
| *ret = c; |
| return 0; |
| } |
| if (errno != ERANGE) { |
| free(c); |
| return -errno; |
| } |
| |
| free(c); |
| |
| if (l > SIZE_MAX / 2) |
| return -ENOMEM; |
| |
| l *= 2; |
| } |
| } |
| |
| int openpt_allocate(int flags, char **ret_slave) { |
| _cleanup_close_ int fd = -1; |
| _cleanup_free_ char *p = NULL; |
| int r; |
| |
| fd = posix_openpt(flags|O_NOCTTY|O_CLOEXEC); |
| if (fd < 0) |
| return -errno; |
| |
| if (ret_slave) { |
| r = ptsname_malloc(fd, &p); |
| if (r < 0) |
| return r; |
| |
| if (!path_startswith(p, "/dev/pts/")) |
| return -EINVAL; |
| } |
| |
| if (unlockpt(fd) < 0) |
| return -errno; |
| |
| if (ret_slave) |
| *ret_slave = TAKE_PTR(p); |
| |
| return TAKE_FD(fd); |
| } |
| |
| static int ptsname_namespace(int pty, char **ret) { |
| int no = -1, r; |
| |
| /* Like ptsname(), but doesn't assume that the path is |
| * accessible in the local namespace. */ |
| |
| r = ioctl(pty, TIOCGPTN, &no); |
| if (r < 0) |
| return -errno; |
| |
| if (no < 0) |
| return -EIO; |
| |
| if (asprintf(ret, "/dev/pts/%i", no) < 0) |
| return -ENOMEM; |
| |
| return 0; |
| } |
| |
| int openpt_allocate_in_namespace(pid_t pid, int flags, char **ret_slave) { |
| _cleanup_close_ int pidnsfd = -1, mntnsfd = -1, usernsfd = -1, rootfd = -1, fd = -1; |
| _cleanup_close_pair_ int pair[2] = { -1, -1 }; |
| pid_t child; |
| int r; |
| |
| assert(pid > 0); |
| |
| r = namespace_open(pid, &pidnsfd, &mntnsfd, NULL, &usernsfd, &rootfd); |
| if (r < 0) |
| return r; |
| |
| if (socketpair(AF_UNIX, SOCK_DGRAM, 0, pair) < 0) |
| return -errno; |
| |
| r = namespace_fork("(sd-openptns)", "(sd-openpt)", NULL, 0, FORK_RESET_SIGNALS|FORK_DEATHSIG, |
| pidnsfd, mntnsfd, -1, usernsfd, rootfd, &child); |
| if (r < 0) |
| return r; |
| if (r == 0) { |
| pair[0] = safe_close(pair[0]); |
| |
| fd = openpt_allocate(flags, NULL); |
| if (fd < 0) |
| _exit(EXIT_FAILURE); |
| |
| if (send_one_fd(pair[1], fd, 0) < 0) |
| _exit(EXIT_FAILURE); |
| |
| _exit(EXIT_SUCCESS); |
| } |
| |
| pair[1] = safe_close(pair[1]); |
| |
| r = wait_for_terminate_and_check("(sd-openptns)", child, 0); |
| if (r < 0) |
| return r; |
| if (r != EXIT_SUCCESS) |
| return -EIO; |
| |
| fd = receive_one_fd(pair[0], 0); |
| if (fd < 0) |
| return fd; |
| |
| if (ret_slave) { |
| r = ptsname_namespace(fd, ret_slave); |
| if (r < 0) |
| return r; |
| } |
| |
| return TAKE_FD(fd); |
| } |
| |
| int open_terminal_in_namespace(pid_t pid, const char *name, int mode) { |
| _cleanup_close_ int pidnsfd = -1, mntnsfd = -1, usernsfd = -1, rootfd = -1; |
| _cleanup_close_pair_ int pair[2] = { -1, -1 }; |
| pid_t child; |
| int r; |
| |
| r = namespace_open(pid, &pidnsfd, &mntnsfd, NULL, &usernsfd, &rootfd); |
| if (r < 0) |
| return r; |
| |
| if (socketpair(AF_UNIX, SOCK_DGRAM, 0, pair) < 0) |
| return -errno; |
| |
| r = namespace_fork("(sd-terminalns)", "(sd-terminal)", NULL, 0, FORK_RESET_SIGNALS|FORK_DEATHSIG, |
| pidnsfd, mntnsfd, -1, usernsfd, rootfd, &child); |
| if (r < 0) |
| return r; |
| if (r == 0) { |
| int master; |
| |
| pair[0] = safe_close(pair[0]); |
| |
| master = open_terminal(name, mode|O_NOCTTY|O_CLOEXEC); |
| if (master < 0) |
| _exit(EXIT_FAILURE); |
| |
| if (send_one_fd(pair[1], master, 0) < 0) |
| _exit(EXIT_FAILURE); |
| |
| _exit(EXIT_SUCCESS); |
| } |
| |
| pair[1] = safe_close(pair[1]); |
| |
| r = wait_for_terminate_and_check("(sd-terminalns)", child, 0); |
| if (r < 0) |
| return r; |
| if (r != EXIT_SUCCESS) |
| return -EIO; |
| |
| return receive_one_fd(pair[0], 0); |
| } |
| |
| static bool getenv_terminal_is_dumb(void) { |
| const char *e; |
| |
| e = getenv("TERM"); |
| if (!e) |
| return true; |
| |
| return streq(e, "dumb"); |
| } |
| |
| bool terminal_is_dumb(void) { |
| if (!on_tty()) |
| return true; |
| |
| return getenv_terminal_is_dumb(); |
| } |
| |
| static ColorMode parse_systemd_colors(void) { |
| const char *e; |
| int r; |
| |
| e = getenv("SYSTEMD_COLORS"); |
| if (!e) |
| return _COLOR_INVALID; |
| if (streq(e, "16")) |
| return COLOR_16; |
| if (streq(e, "256")) |
| return COLOR_256; |
| r = parse_boolean(e); |
| if (r >= 0) |
| return r > 0 ? COLOR_ON : COLOR_OFF; |
| return _COLOR_INVALID; |
| } |
| |
| ColorMode get_color_mode(void) { |
| |
| /* Returns the mode used to choose output colors. The possible modes are COLOR_OFF for no colors, |
| * COLOR_16 for only the base 16 ANSI colors, COLOR_256 for more colors and COLOR_ON for unrestricted |
| * color output. For that we check $SYSTEMD_COLORS first (which is the explicit way to |
| * change the mode). If that didn't work we turn colors off unless we are on a TTY. And if we are on a TTY |
| * we turn it off if $TERM is set to "dumb". There's one special tweak though: if we are PID 1 then we do not |
| * check whether we are connected to a TTY, because we don't keep /dev/console open continuously due to fear |
| * of SAK, and hence things are a bit weird. */ |
| ColorMode m; |
| |
| if (cached_color_mode < 0) { |
| m = parse_systemd_colors(); |
| if (m >= 0) |
| cached_color_mode = m; |
| else if (getenv("NO_COLOR")) |
| /* We only check for the presence of the variable; value is ignored. */ |
| cached_color_mode = COLOR_OFF; |
| |
| else if (getpid_cached() == 1) |
| /* PID1 outputs to the console without holding it open all the time. |
| * |
| * Note that the Linux console can only display 16 colors. We still enable 256 color |
| * mode even for PID1 output though (which typically goes to the Linux console), |
| * since the Linux console is able to parse the 256 color sequences and automatically |
| * map them to the closest color in the 16 color palette (since kernel 3.16). Doing |
| * 256 colors is nice for people who invoke systemd in a container or via a serial |
| * link or such, and use a true 256 color terminal to do so. */ |
| cached_color_mode = getenv_terminal_is_dumb() ? COLOR_OFF : COLOR_256; |
| else |
| cached_color_mode = terminal_is_dumb() ? COLOR_OFF : COLOR_256; |
| } |
| |
| return cached_color_mode; |
| } |
| |
| bool dev_console_colors_enabled(void) { |
| _cleanup_free_ char *s = NULL; |
| ColorMode m; |
| |
| /* Returns true if we assume that color is supported on /dev/console. |
| * |
| * For that we first check if we explicitly got told to use colors or not, by checking $SYSTEMD_COLORS. If that |
| * isn't set we check whether PID 1 has $TERM set, and if not, whether TERM is set on the kernel command |
| * line. If we find $TERM set we assume color if it's not set to "dumb", similarly to how regular |
| * colors_enabled() operates. */ |
| |
| m = parse_systemd_colors(); |
| if (m >= 0) |
| return m; |
| |
| if (getenv("NO_COLOR")) |
| return false; |
| |
| if (getenv_for_pid(1, "TERM", &s) <= 0) |
| (void) proc_cmdline_get_key("TERM", 0, &s); |
| |
| return !streq_ptr(s, "dumb"); |
| } |
| |
| bool underline_enabled(void) { |
| |
| if (cached_underline_enabled < 0) { |
| |
| /* The Linux console doesn't support underlining, turn it off, but only there. */ |
| |
| if (colors_enabled()) |
| cached_underline_enabled = !streq_ptr(getenv("TERM"), "linux"); |
| else |
| cached_underline_enabled = false; |
| } |
| |
| return cached_underline_enabled; |
| } |
| |
| int vt_default_utf8(void) { |
| _cleanup_free_ char *b = NULL; |
| int r; |
| |
| /* Read the default VT UTF8 setting from the kernel */ |
| |
| r = read_one_line_file("/sys/module/vt/parameters/default_utf8", &b); |
| if (r < 0) |
| return r; |
| |
| return parse_boolean(b); |
| } |
| |
| int vt_reset_keyboard(int fd) { |
| int kb; |
| |
| /* If we can't read the default, then default to unicode. It's 2017 after all. */ |
| kb = vt_default_utf8() != 0 ? K_UNICODE : K_XLATE; |
| |
| if (ioctl(fd, KDSKBMODE, kb) < 0) |
| return -errno; |
| |
| return 0; |
| } |
| |
| int vt_restore(int fd) { |
| static const struct vt_mode mode = { |
| .mode = VT_AUTO, |
| }; |
| int r, q = 0; |
| |
| if (isatty(fd) < 1) |
| return log_debug_errno(errno, "Asked to restore the VT for an fd that does not refer to a terminal: %m"); |
| |
| if (ioctl(fd, KDSETMODE, KD_TEXT) < 0) |
| q = log_debug_errno(errno, "Failed to set VT in text mode, ignoring: %m"); |
| |
| r = vt_reset_keyboard(fd); |
| if (r < 0) { |
| log_debug_errno(r, "Failed to reset keyboard mode, ignoring: %m"); |
| if (q >= 0) |
| q = r; |
| } |
| |
| if (ioctl(fd, VT_SETMODE, &mode) < 0) { |
| log_debug_errno(errno, "Failed to set VT_AUTO mode, ignoring: %m"); |
| if (q >= 0) |
| q = -errno; |
| } |
| |
| r = fchmod_and_chown(fd, TTY_MODE, 0, GID_INVALID); |
| if (r < 0) { |
| log_debug_errno(r, "Failed to chmod()/chown() VT, ignoring: %m"); |
| if (q >= 0) |
| q = r; |
| } |
| |
| return q; |
| } |
| |
| int vt_release(int fd, bool restore) { |
| assert(fd >= 0); |
| |
| /* This function releases the VT by acknowledging the VT-switch signal |
| * sent by the kernel and optionally reset the VT in text and auto |
| * VT-switching modes. */ |
| |
| if (isatty(fd) < 1) |
| return log_debug_errno(errno, "Asked to release the VT for an fd that does not refer to a terminal: %m"); |
| |
| if (ioctl(fd, VT_RELDISP, 1) < 0) |
| return -errno; |
| |
| if (restore) |
| return vt_restore(fd); |
| |
| return 0; |
| } |
| |
| void get_log_colors(int priority, const char **on, const char **off, const char **highlight) { |
| /* Note that this will initialize output variables only when there's something to output. |
| * The caller must pre-initialize to "" or NULL as appropriate. */ |
| |
| if (priority <= LOG_ERR) { |
| if (on) |
| *on = ansi_highlight_red(); |
| if (off) |
| *off = ansi_normal(); |
| if (highlight) |
| *highlight = ansi_highlight(); |
| |
| } else if (priority <= LOG_WARNING) { |
| if (on) |
| *on = ansi_highlight_yellow(); |
| if (off) |
| *off = ansi_normal(); |
| if (highlight) |
| *highlight = ansi_highlight(); |
| |
| } else if (priority <= LOG_NOTICE) { |
| if (on) |
| *on = ansi_highlight(); |
| if (off) |
| *off = ansi_normal(); |
| if (highlight) |
| *highlight = ansi_highlight_red(); |
| |
| } else if (priority >= LOG_DEBUG) { |
| if (on) |
| *on = ansi_grey(); |
| if (off) |
| *off = ansi_normal(); |
| if (highlight) |
| *highlight = ansi_highlight_red(); |
| } |
| } |
