+++ /dev/null
-/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
-
-/***
- 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 <utmpx.h>
-#include <errno.h>
-#include <string.h>
-#include <sys/utsname.h>
-#include <fcntl.h>
-#include <unistd.h>
-#include <poll.h>
-
-#include "macro.h"
-#include "path-util.h"
-#include "terminal-util.h"
-#include "hostname-util.h"
-#include "utmp-wtmp.h"
-
-int utmp_get_runlevel(int *runlevel, int *previous) {
- struct utmpx *found, lookup = { .ut_type = RUN_LVL };
- int r;
- const char *e;
-
- assert(runlevel);
-
- /* If these values are set in the environment this takes
- * precedence. Presumably, sysvinit does this to work around a
- * race condition that would otherwise exist where we'd always
- * go to disk and hence might read runlevel data that might be
- * very new and does not apply to the current script being
- * executed. */
-
- e = getenv("RUNLEVEL");
- if (e && e[0] > 0) {
- *runlevel = e[0];
-
- if (previous) {
- /* $PREVLEVEL seems to be an Upstart thing */
-
- e = getenv("PREVLEVEL");
- if (e && e[0] > 0)
- *previous = e[0];
- else
- *previous = 0;
- }
-
- return 0;
- }
-
- if (utmpxname(_PATH_UTMPX) < 0)
- return -errno;
-
- setutxent();
-
- found = getutxid(&lookup);
- if (!found)
- r = -errno;
- else {
- int a, b;
-
- a = found->ut_pid & 0xFF;
- b = (found->ut_pid >> 8) & 0xFF;
-
- *runlevel = a;
- if (previous)
- *previous = b;
-
- r = 0;
- }
-
- endutxent();
-
- return r;
-}
-
-static void init_timestamp(struct utmpx *store, usec_t t) {
- assert(store);
-
- if (t <= 0)
- t = now(CLOCK_REALTIME);
-
- store->ut_tv.tv_sec = t / USEC_PER_SEC;
- store->ut_tv.tv_usec = t % USEC_PER_SEC;
-}
-
-static void init_entry(struct utmpx *store, usec_t t) {
- struct utsname uts = {};
-
- assert(store);
-
- init_timestamp(store, t);
-
- if (uname(&uts) >= 0)
- strncpy(store->ut_host, uts.release, sizeof(store->ut_host));
-
- strncpy(store->ut_line, "~", sizeof(store->ut_line)); /* or ~~ ? */
- strncpy(store->ut_id, "~~", sizeof(store->ut_id));
-}
-
-static int write_entry_utmp(const struct utmpx *store) {
- int r;
-
- assert(store);
-
- /* utmp is similar to wtmp, but there is only one entry for
- * each entry type resp. user; i.e. basically a key/value
- * table. */
-
- if (utmpxname(_PATH_UTMPX) < 0)
- return -errno;
-
- setutxent();
-
- if (!pututxline(store))
- r = -errno;
- else
- r = 0;
-
- endutxent();
-
- return r;
-}
-
-static int write_entry_wtmp(const struct utmpx *store) {
- assert(store);
-
- /* wtmp is a simple append-only file where each entry is
- simply appended to the end; i.e. basically a log. */
-
- errno = 0;
- updwtmpx(_PATH_WTMPX, store);
- return -errno;
-}
-
-static int write_utmp_wtmp(const struct utmpx *store_utmp, const struct utmpx *store_wtmp) {
- int r, s;
-
- r = write_entry_utmp(store_utmp);
- s = write_entry_wtmp(store_wtmp);
-
- if (r >= 0)
- r = s;
-
- /* If utmp/wtmp have been disabled, that's a good thing, hence
- * ignore the errors */
- if (r == -ENOENT)
- r = 0;
-
- return r;
-}
-
-static int write_entry_both(const struct utmpx *store) {
- return write_utmp_wtmp(store, store);
-}
-
-int utmp_put_shutdown(void) {
- struct utmpx store = {};
-
- init_entry(&store, 0);
-
- store.ut_type = RUN_LVL;
- strncpy(store.ut_user, "shutdown", sizeof(store.ut_user));
-
- return write_entry_both(&store);
-}
-
-int utmp_put_reboot(usec_t t) {
- struct utmpx store = {};
-
- init_entry(&store, t);
-
- store.ut_type = BOOT_TIME;
- strncpy(store.ut_user, "reboot", sizeof(store.ut_user));
-
- return write_entry_both(&store);
-}
-
-_pure_ static const char *sanitize_id(const char *id) {
- size_t l;
-
- assert(id);
- l = strlen(id);
-
- if (l <= sizeof(((struct utmpx*) NULL)->ut_id))
- return id;
-
- return id + l - sizeof(((struct utmpx*) NULL)->ut_id);
-}
-
-int utmp_put_init_process(const char *id, pid_t pid, pid_t sid, const char *line) {
- struct utmpx store = {
- .ut_type = INIT_PROCESS,
- .ut_pid = pid,
- .ut_session = sid,
- };
-
- assert(id);
-
- init_timestamp(&store, 0);
-
- /* ut_id needs only be nul-terminated if it is shorter than sizeof(ut_id) */
- strncpy(store.ut_id, sanitize_id(id), sizeof(store.ut_id));
-
- if (line)
- strncpy(store.ut_line, basename(line), sizeof(store.ut_line));
-
- return write_entry_both(&store);
-}
-
-int utmp_put_dead_process(const char *id, pid_t pid, int code, int status) {
- struct utmpx lookup = {
- .ut_type = INIT_PROCESS /* looks for DEAD_PROCESS, LOGIN_PROCESS, USER_PROCESS, too */
- }, store, store_wtmp, *found;
-
- assert(id);
-
- setutxent();
-
- /* ut_id needs only be nul-terminated if it is shorter than sizeof(ut_id) */
- strncpy(lookup.ut_id, sanitize_id(id), sizeof(lookup.ut_id));
-
- found = getutxid(&lookup);
- if (!found)
- return 0;
-
- if (found->ut_pid != pid)
- return 0;
-
- memcpy(&store, found, sizeof(store));
- store.ut_type = DEAD_PROCESS;
- store.ut_exit.e_termination = code;
- store.ut_exit.e_exit = status;
-
- zero(store.ut_user);
- zero(store.ut_host);
- zero(store.ut_tv);
-
- memcpy(&store_wtmp, &store, sizeof(store_wtmp));
- /* wtmp wants the current time */
- init_timestamp(&store_wtmp, 0);
-
- return write_utmp_wtmp(&store, &store_wtmp);
-}
-
-
-int utmp_put_runlevel(int runlevel, int previous) {
- struct utmpx store = {};
- int r;
-
- assert(runlevel > 0);
-
- if (previous <= 0) {
- /* Find the old runlevel automatically */
-
- r = utmp_get_runlevel(&previous, NULL);
- if (r < 0) {
- if (r != -ESRCH)
- return r;
-
- previous = 0;
- }
- }
-
- if (previous == runlevel)
- return 0;
-
- init_entry(&store, 0);
-
- store.ut_type = RUN_LVL;
- store.ut_pid = (runlevel & 0xFF) | ((previous & 0xFF) << 8);
- strncpy(store.ut_user, "runlevel", sizeof(store.ut_user));
-
- return write_entry_both(&store);
-}
-
-#define TIMEOUT_MSEC 50
-
-static int write_to_terminal(const char *tty, const char *message) {
- _cleanup_close_ int fd = -1;
- const char *p;
- size_t left;
- usec_t end;
-
- assert(tty);
- assert(message);
-
- fd = open(tty, O_WRONLY|O_NDELAY|O_NOCTTY|O_CLOEXEC);
- if (fd < 0 || !isatty(fd))
- return -errno;
-
- p = message;
- left = strlen(message);
-
- end = now(CLOCK_MONOTONIC) + TIMEOUT_MSEC*USEC_PER_MSEC;
-
- while (left > 0) {
- ssize_t n;
- struct pollfd pollfd = {
- .fd = fd,
- .events = POLLOUT,
- };
- usec_t t;
- int k;
-
- t = now(CLOCK_MONOTONIC);
-
- if (t >= end)
- return -ETIME;
-
- k = poll(&pollfd, 1, (end - t) / USEC_PER_MSEC);
- if (k < 0)
- return -errno;
-
- if (k == 0)
- return -ETIME;
-
- n = write(fd, p, left);
- if (n < 0) {
- if (errno == EAGAIN)
- continue;
-
- return -errno;
- }
-
- assert((size_t) n <= left);
-
- p += n;
- left -= n;
- }
-
- return 0;
-}
-
-int utmp_wall(const char *message, const char *username, bool (*match_tty)(const char *tty)) {
- _cleanup_free_ char *text = NULL, *hn = NULL, *un = NULL, *tty = NULL;
- char date[FORMAT_TIMESTAMP_MAX];
- struct utmpx *u;
- int r;
-
- hn = gethostname_malloc();
- if (!hn)
- return -ENOMEM;
- if (!username) {
- un = getlogname_malloc();
- if (!un)
- return -ENOMEM;
- }
-
- getttyname_harder(STDIN_FILENO, &tty);
-
- if (asprintf(&text,
- "\a\r\n"
- "Broadcast message from %s@%s%s%s (%s):\r\n\r\n"
- "%s\r\n\r\n",
- un ?: username, hn,
- tty ? " on " : "", strempty(tty),
- format_timestamp(date, sizeof(date), now(CLOCK_REALTIME)),
- message) < 0)
- return -ENOMEM;
-
- setutxent();
-
- r = 0;
-
- while ((u = getutxent())) {
- _cleanup_free_ char *buf = NULL;
- const char *path;
- int q;
-
- if (u->ut_type != USER_PROCESS || u->ut_user[0] == 0)
- continue;
-
- /* this access is fine, because strlen("/dev/") << 32 (UT_LINESIZE) */
- if (path_startswith(u->ut_line, "/dev/"))
- path = u->ut_line;
- else {
- if (asprintf(&buf, "/dev/%.*s", (int) sizeof(u->ut_line), u->ut_line) < 0)
- return -ENOMEM;
-
- path = buf;
- }
-
- if (!match_tty || match_tty(path)) {
- q = write_to_terminal(path, text);
- if (q < 0)
- r = q;
- }
- }
-
- return r;
-}
~ianmdlvl / elogind.git / blobdiff