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/*
* utmpwatcher.c
*
* Copyright (C) 2006 Red Hat
* see file 'COPYING' for use and warranty information
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of
* the License, or (at your option) any later version.
*
* This program 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 General Public License for more details.
.*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
* 02111-1307 USA
*
* Authors:
* Dan Walsh <dwalsh@redhat.com>
*
*
*/
#define _GNU_SOURCE
#include <sys/inotify.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <syslog.h>
#include <limits.h>
#include <utmp.h>
#include <sys/types.h>
#include <pwd.h>
#include "restorecond.h"
#include "utmpwatcher.h"
#include "stringslist.h"
static struct stringsList *utmp_ptr = NULL;
static int utmp_wd = -1;
unsigned int utmpwatcher_handle(int inotify_fd, int wd)
{
int changed = 0;
struct utmp u;
const char *utmp_path = "/var/run/utmp";
struct stringsList *prev_utmp_ptr = utmp_ptr;
if (wd != utmp_wd)
return -1;
utmp_ptr = NULL;
FILE *cfg = fopen(utmp_path, "r");
if (!cfg)
exitApp("Error reading utmp file.");
while (fread(&u, sizeof(struct utmp), 1, cfg) > 0) {
if (u.ut_type == USER_PROCESS)
strings_list_add(&utmp_ptr, u.ut_user);
}
fclose(cfg);
if (utmp_wd >= 0)
inotify_rm_watch(inotify_fd, utmp_wd);
utmp_wd =
inotify_add_watch(inotify_fd, utmp_path, IN_MOVED_FROM | IN_MODIFY);
if (utmp_wd == -1)
exitApp("Error watching utmp file.");
changed = strings_list_diff(prev_utmp_ptr, utmp_ptr);
if (prev_utmp_ptr) {
strings_list_free(prev_utmp_ptr);
}
return changed;
}
static void watch_file(int inotify_fd, const char *file)
{
struct stringsList *ptr = utmp_ptr;
while (ptr) {
struct passwd *pwd = getpwnam(ptr->string);
if (pwd) {
char *path = NULL;
if (asprintf(&path, "%s%s", pwd->pw_dir, file) < 0)
exitApp("Error allocating memory.");
watch_list_add(inotify_fd, path);
free(path);
}
ptr = ptr->next;
}
}
void utmpwatcher_add(int inotify_fd, const char *path)
{
if (utmp_ptr == NULL) {
utmpwatcher_handle(inotify_fd, utmp_wd);
}
watch_file(inotify_fd, path);
}
void utmpwatcher_free(void)
{
if (utmp_ptr)
strings_list_free(utmp_ptr);
}
#ifdef TEST
int main(int argc, char **argv)
{
read_utmp();
return 0;
}
#endif