| /*** |
| This file is part of systemd. |
| |
| Copyright 2010 Lennart Poettering |
| |
| systemd is free software; you can redistribute it and/or modify it |
| under the terms of the GNU Lesser General Public License as published by |
| the Free Software Foundation; either version 2.1 of the License, or |
| (at your option) any later version. |
| |
| systemd is distributed in the hope that it will be useful, but |
| WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| Lesser General Public License for more details. |
| |
| You should have received a copy of the GNU Lesser General Public License |
| along with systemd; If not, see <http://www.gnu.org/licenses/>. |
| ***/ |
| |
| #include <errno.h> |
| #include <fcntl.h> |
| #include <limits.h> |
| #include <stdarg.h> |
| #include <stddef.h> |
| #include <stdlib.h> |
| #include <string.h> |
| #include <sys/inotify.h> |
| #include <sys/socket.h> |
| #include <sys/sysmacros.h> |
| #include <sys/time.h> |
| #include <linux/kd.h> |
| #include <linux/tiocl.h> |
| #include <linux/vt.h> |
| #include <poll.h> |
| #include <signal.h> |
| #include <sys/ioctl.h> |
| #include <sys/types.h> |
| #include <termios.h> |
| #include <unistd.h> |
| |
| #include "alloc-util.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 "parse-util.h" |
| #include "process-util.h" |
| #include "socket-util.h" |
| #include "stat-util.h" |
| #include "string-util.h" |
| #include "strv.h" |
| #include "terminal-util.h" |
| #include "time-util.h" |
| #include "util.h" |
| |
| static volatile unsigned cached_columns = 0; |
| static volatile unsigned cached_lines = 0; |
| |
| int chvt(int vt) { |
| _cleanup_close_ int fd; |
| |
| 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) { |
| struct termios old_termios, new_termios; |
| char c, line[LINE_MAX]; |
| |
| assert(f); |
| assert(ret); |
| |
| if (tcgetattr(fileno(f), &old_termios) >= 0) { |
| new_termios = old_termios; |
| |
| new_termios.c_lflag &= ~ICANON; |
| new_termios.c_cc[VMIN] = 1; |
| new_termios.c_cc[VTIME] = 0; |
| |
| if (tcsetattr(fileno(f), TCSADRAIN, &new_termios) >= 0) { |
| size_t k; |
| |
| if (t != USEC_INFINITY) { |
| if (fd_wait_for_event(fileno(f), POLLIN, t) <= 0) { |
| tcsetattr(fileno(f), TCSADRAIN, &old_termios); |
| return -ETIMEDOUT; |
| } |
| } |
| |
| k = fread(&c, 1, 1, f); |
| |
| tcsetattr(fileno(f), TCSADRAIN, &old_termios); |
| |
| if (k <= 0) |
| return -EIO; |
| |
| if (need_nl) |
| *need_nl = c != '\n'; |
| |
| *ret = c; |
| return 0; |
| } |
| } |
| |
| if (t != USEC_INFINITY) { |
| if (fd_wait_for_event(fileno(f), POLLIN, t) <= 0) |
| return -ETIMEDOUT; |
| } |
| |
| errno = 0; |
| if (!fgets(line, sizeof(line), f)) |
| return errno > 0 ? -errno : -EIO; |
| |
| truncate_nl(line); |
| |
| if (strlen(line) != 1) |
| return -EBADMSG; |
| |
| if (need_nl) |
| *need_nl = false; |
| |
| *ret = line[0]; |
| return 0; |
| } |
| |
| int ask_char(char *ret, const char *replies, const char *text, ...) { |
| int r; |
| |
| assert(ret); |
| assert(replies); |
| assert(text); |
| |
| for (;;) { |
| va_list ap; |
| char c; |
| bool need_nl = true; |
| |
| if (colors_enabled()) |
| fputs(ANSI_HIGHLIGHT, stdout); |
| |
| va_start(ap, text); |
| vprintf(text, ap); |
| va_end(ap); |
| |
| if (colors_enabled()) |
| fputs(ANSI_NORMAL, stdout); |
| |
| fflush(stdout); |
| |
| r = read_one_char(stdin, &c, USEC_INFINITY, &need_nl); |
| if (r < 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 ask_string(char **ret, const char *text, ...) { |
| assert(ret); |
| assert(text); |
| |
| for (;;) { |
| char line[LINE_MAX]; |
| va_list ap; |
| |
| if (colors_enabled()) |
| fputs(ANSI_HIGHLIGHT, stdout); |
| |
| va_start(ap, text); |
| vprintf(text, ap); |
| va_end(ap); |
| |
| if (colors_enabled()) |
| fputs(ANSI_NORMAL, stdout); |
| |
| fflush(stdout); |
| |
| errno = 0; |
| if (!fgets(line, sizeof(line), stdin)) |
| return errno > 0 ? -errno : -EIO; |
| |
| if (!endswith(line, "\n")) |
| putchar('\n'); |
| else { |
| char *s; |
| |
| if (isempty(line)) |
| continue; |
| |
| truncate_nl(line); |
| s = strdup(line); |
| if (!s) |
| return -ENOMEM; |
| |
| *ret = s; |
| 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); |
| |
| /* 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 */ |
| (void) ioctl(fd, TIOCNXCL); |
| |
| /* Switch to text mode */ |
| if (switch_to_text) |
| (void) ioctl(fd, KDSETMODE, KD_TEXT); |
| |
| /* Enable console unicode mode */ |
| (void) ioctl(fd, KDSKBMODE, K_UNICODE); |
| |
| 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 */ |
| (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) { |
| int fd, r; |
| 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; |
| |
| usleep(50 * USEC_PER_MSEC); |
| c++; |
| } |
| |
| r = isatty(fd); |
| if (r == 0) { |
| safe_close(fd); |
| return -ENOTTY; |
| } |
| |
| return fd; |
| } |
| |
| int acquire_terminal( |
| const char *name, |
| bool fail, |
| bool force, |
| bool ignore_tiocstty_eperm, |
| usec_t timeout) { |
| |
| int fd = -1, notify = -1, r = 0, wd = -1; |
| usec_t ts = 0; |
| |
| 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 (timeout != USEC_INFINITY) |
| ts = now(CLOCK_MONOTONIC); |
| |
| if (!fail && !force) { |
| notify = inotify_init1(IN_CLOEXEC | (timeout != USEC_INFINITY ? IN_NONBLOCK : 0)); |
| if (notify < 0) { |
| r = -errno; |
| goto fail; |
| } |
| |
| wd = inotify_add_watch(notify, name, IN_CLOSE); |
| if (wd < 0) { |
| r = -errno; |
| goto fail; |
| } |
| } |
| |
| 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) |
| 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 */ |
| 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 */ |
| if (ioctl(fd, TIOCSCTTY, force) < 0) |
| r = -errno; |
| |
| assert_se(sigaction(SIGHUP, &sa_old, NULL) == 0); |
| |
| /* Sometimes, it makes sense to ignore TIOCSCTTY |
| * returning EPERM, i.e. when very likely we already |
| * are have this controlling terminal. */ |
| if (r < 0 && r == -EPERM && ignore_tiocstty_eperm) |
| r = 0; |
| |
| if (r < 0 && (force || fail || r != -EPERM)) |
| goto fail; |
| |
| if (r >= 0) |
| break; |
| |
| assert(!fail); |
| assert(!force); |
| assert(notify >= 0); |
| |
| for (;;) { |
| union inotify_event_buffer buffer; |
| struct inotify_event *e; |
| ssize_t l; |
| |
| if (timeout != USEC_INFINITY) { |
| usec_t n; |
| |
| n = now(CLOCK_MONOTONIC); |
| if (ts + timeout < n) { |
| r = -ETIMEDOUT; |
| goto fail; |
| } |
| |
| r = fd_wait_for_event(fd, POLLIN, ts + timeout - n); |
| if (r < 0) |
| goto fail; |
| |
| if (r == 0) { |
| r = -ETIMEDOUT; |
| goto fail; |
| } |
| } |
| |
| l = read(notify, &buffer, sizeof(buffer)); |
| if (l < 0) { |
| if (errno == EINTR || errno == EAGAIN) |
| continue; |
| |
| r = -errno; |
| goto fail; |
| } |
| |
| FOREACH_INOTIFY_EVENT(e, buffer, l) { |
| if (e->wd != wd || !(e->mask & IN_CLOSE)) { |
| r = -EIO; |
| 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. */ |
| fd = safe_close(fd); |
| } |
| |
| safe_close(notify); |
| |
| return fd; |
| |
| fail: |
| safe_close(fd); |
| safe_close(notify); |
| |
| return r; |
| } |
| |
| 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 = 0; |
| |
| 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); |
| |
| if (ioctl(fd, TIOCNOTTY) < 0) |
| r = -errno; |
| |
| 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; |
| |
| 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) { |
| _cleanup_close_ int fd = -1; |
| unsigned u; |
| 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) */ |
| |
| if (!startswith(name, "/dev/")) |
| return -EINVAL; |
| |
| if (!tty_is_vc(name)) { |
| /* So this is not a VT. I guess we cannot deallocate |
| * it then. But let's at least clear the screen */ |
| |
| fd = open_terminal(name, O_RDWR|O_NOCTTY|O_CLOEXEC); |
| if (fd < 0) |
| return fd; |
| |
| loop_write(fd, |
| "\033[r" /* clear scrolling region */ |
| "\033[H" /* move home */ |
| "\033[2J", /* clear screen */ |
| 10, false); |
| return 0; |
| } |
| |
| if (!startswith(name, "/dev/tty")) |
| return -EINVAL; |
| |
| r = safe_atou(name+8, &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); |
| fd = safe_close(fd); |
| |
| if (r >= 0) |
| return 0; |
| |
| if (errno != EBUSY) |
| return -errno; |
| |
| /* Couldn't deallocate, so let's clear it fully with |
| * scrollback */ |
| fd = open_terminal(name, O_RDWR|O_NOCTTY|O_CLOEXEC); |
| if (fd < 0) |
| return fd; |
| |
| loop_write(fd, |
| "\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 */ |
| |
| fd = acquire_terminal("/dev/console", false, true, true, USEC_INFINITY); |
| if (fd < 0) |
| return log_error_errno(fd, "Failed to acquire terminal: %m"); |
| |
| r = reset_terminal_fd(fd, true); |
| if (r < 0) |
| log_warning_errno(r, "Failed to reset terminal, ignoring: %m"); |
| |
| r = make_stdio(fd); |
| if (r < 0) |
| return log_error_errno(r, "Failed to duplicate terminal fd: %m"); |
| |
| 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); |
| |
| if (startswith(tty, "/dev/")) |
| tty += 5; |
| |
| return streq(tty, "console"); |
| } |
| |
| int vtnr_from_tty(const char *tty) { |
| int i, r; |
| |
| assert(tty); |
| |
| if (startswith(tty, "/dev/")) |
| tty += 5; |
| |
| 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; |
| } |
| |
| char *resolve_dev_console(char **active) { |
| char *tty; |
| |
| /* 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 NULL; |
| |
| if (read_one_line_file("/sys/class/tty/console/active", active) < 0) |
| return NULL; |
| |
| /* 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")) { |
| char *tmp; |
| |
| /* Get the active VC (e.g. tty1) */ |
| if (read_one_line_file("/sys/class/tty/tty0/active", &tmp) >= 0) { |
| free(*active); |
| tty = *active = tmp; |
| } |
| } |
| |
| return tty; |
| } |
| |
| int get_kernel_consoles(char ***consoles) { |
| _cleanup_strv_free_ char **con = NULL; |
| _cleanup_free_ char *line = NULL; |
| const char *active; |
| int r; |
| |
| assert(consoles); |
| |
| r = read_one_line_file("/sys/class/tty/console/active", &line); |
| if (r < 0) |
| return r; |
| |
| active = line; |
| for (;;) { |
| _cleanup_free_ char *tty = NULL; |
| char *path; |
| |
| r = extract_first_word(&active, &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 = strappend("/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); |
| free(path); |
| continue; |
| } |
| |
| r = strv_consume(&con, path); |
| if (r < 0) |
| return r; |
| } |
| |
| if (strv_isempty(con)) { |
| log_debug("No devices found for system console"); |
| |
| r = strv_extend(&con, "/dev/console"); |
| if (r < 0) |
| return r; |
| } |
| |
| *consoles = con; |
| con = NULL; |
| return 0; |
| } |
| |
| bool tty_is_vc_resolve(const char *tty) { |
| _cleanup_free_ char *active = NULL; |
| |
| assert(tty); |
| |
| if (startswith(tty, "/dev/")) |
| tty += 5; |
| |
| if (streq(tty, "console")) { |
| tty = resolve_dev_console(&active); |
| if (!tty) |
| return false; |
| } |
| |
| 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 (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 (_likely_(cached_columns > 0)) |
| return cached_columns; |
| |
| c = 0; |
| e = getenv("COLUMNS"); |
| if (e) |
| (void) safe_atoi(e, &c); |
| |
| if (c <= 0) |
| 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 (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 (_likely_(cached_lines > 0)) |
| return cached_lines; |
| |
| l = 0; |
| e = getenv("LINES"); |
| if (e) |
| (void) safe_atoi(e, &l); |
| |
| if (l <= 0) |
| 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; |
| } |
| |
| bool on_tty(void) { |
| static int cached_on_tty = -1; |
| |
| if (_unlikely_(cached_on_tty < 0)) |
| cached_on_tty = isatty(STDOUT_FILENO) > 0; |
| |
| return cached_on_tty; |
| } |
| |
| int make_stdio(int fd) { |
| int r, s, t; |
| |
| assert(fd >= 0); |
| |
| r = dup2(fd, STDIN_FILENO); |
| s = dup2(fd, STDOUT_FILENO); |
| t = dup2(fd, STDERR_FILENO); |
| |
| if (fd >= 3) |
| safe_close(fd); |
| |
| if (r < 0 || s < 0 || t < 0) |
| return -errno; |
| |
| /* Explicitly unset O_CLOEXEC, since if fd was < 3, then |
| * dup2() was a NOP and the bit hence possibly set. */ |
| stdio_unset_cloexec(); |
| |
| return 0; |
| } |
| |
| int make_null_stdio(void) { |
| int null_fd; |
| |
| null_fd = open("/dev/null", O_RDWR|O_NOCTTY); |
| if (null_fd < 0) |
| return -errno; |
| |
| return make_stdio(null_fd); |
| } |
| |
| int getttyname_malloc(int fd, char **ret) { |
| size_t l = 100; |
| int r; |
| |
| assert(fd >= 0); |
| assert(ret); |
| |
| for (;;) { |
| char path[l]; |
| |
| r = ttyname_r(fd, path, sizeof(path)); |
| if (r == 0) { |
| const char *p; |
| char *c; |
| |
| p = startswith(path, "/dev/"); |
| c = strdup(p ?: path); |
| if (!c) |
| return -ENOMEM; |
| |
| *ret = c; |
| return 0; |
| } |
| |
| if (r != ERANGE) |
| return -r; |
| |
| l *= 2; |
| } |
| |
| return 0; |
| } |
| |
| int getttyname_harder(int fd, char **r) { |
| int k; |
| char *s = NULL; |
| |
| k = getttyname_malloc(fd, &s); |
| if (k < 0) |
| return k; |
| |
| if (streq(s, "tty")) { |
| free(s); |
| return get_ctty(0, NULL, r); |
| } |
| |
| *r = 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 *_devnr, char **r) { |
| char fn[sizeof("/dev/char/")-1 + 2*DECIMAL_STR_MAX(unsigned) + 1 + 1], *b = NULL; |
| _cleanup_free_ char *s = NULL; |
| const char *p; |
| dev_t devnr; |
| int k; |
| |
| assert(r); |
| |
| k = get_ctty_devnr(pid, &devnr); |
| if (k < 0) |
| return k; |
| |
| sprintf(fn, "/dev/char/%u:%u", major(devnr), minor(devnr)); |
| |
| k = readlink_malloc(fn, &s); |
| if (k < 0) { |
| |
| if (k != -ENOENT) |
| return k; |
| |
| /* This is an ugly hack */ |
| if (major(devnr) == 136) { |
| if (asprintf(&b, "pts/%u", minor(devnr)) < 0) |
| return -ENOMEM; |
| } else { |
| /* Probably something like the ptys which have no |
| * symlink in /dev/char. Let's return something |
| * vaguely useful. */ |
| |
| b = strdup(fn + 5); |
| if (!b) |
| return -ENOMEM; |
| } |
| } else { |
| if (startswith(s, "/dev/")) |
| p = s + 5; |
| else if (startswith(s, "../")) |
| p = s + 3; |
| else |
| p = s; |
| |
| b = strdup(p); |
| if (!b) |
| return -ENOMEM; |
| } |
| |
| *r = b; |
| if (_devnr) |
| *_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); |
| l *= 2; |
| } |
| } |
| |
| 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_in_namespace(pid_t pid, int flags) { |
| _cleanup_close_ int pidnsfd = -1, mntnsfd = -1, usernsfd = -1, rootfd = -1; |
| _cleanup_close_pair_ int pair[2] = { -1, -1 }; |
| siginfo_t si; |
| 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; |
| |
| child = fork(); |
| if (child < 0) |
| return -errno; |
| |
| if (child == 0) { |
| int master; |
| |
| pair[0] = safe_close(pair[0]); |
| |
| r = namespace_enter(pidnsfd, mntnsfd, -1, usernsfd, rootfd); |
| if (r < 0) |
| _exit(EXIT_FAILURE); |
| |
| master = posix_openpt(flags|O_NOCTTY|O_CLOEXEC); |
| if (master < 0) |
| _exit(EXIT_FAILURE); |
| |
| if (unlockpt(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(child, &si); |
| if (r < 0) |
| return r; |
| if (si.si_code != CLD_EXITED || si.si_status != EXIT_SUCCESS) |
| return -EIO; |
| |
| return receive_one_fd(pair[0], 0); |
| } |
| |
| 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 }; |
| siginfo_t si; |
| 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; |
| |
| child = fork(); |
| if (child < 0) |
| return -errno; |
| |
| if (child == 0) { |
| int master; |
| |
| pair[0] = safe_close(pair[0]); |
| |
| r = namespace_enter(pidnsfd, mntnsfd, -1, usernsfd, rootfd); |
| if (r < 0) |
| _exit(EXIT_FAILURE); |
| |
| 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(child, &si); |
| if (r < 0) |
| return r; |
| if (si.si_code != CLD_EXITED || si.si_status != 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(); |
| } |
| |
| bool colors_enabled(void) { |
| static int enabled = -1; |
| |
| if (_unlikely_(enabled < 0)) { |
| int val; |
| |
| val = getenv_bool("SYSTEMD_COLORS"); |
| if (val >= 0) |
| enabled = val; |
| else if (getpid() == 1) |
| /* PID1 outputs to the console without holding it open all the time */ |
| enabled = !getenv_terminal_is_dumb(); |
| else |
| enabled = !terminal_is_dumb(); |
| } |
| |
| return enabled; |
| } |