Aren
/
NetBSD
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity
NetBSD/usr.bin/who/utmpentry.c

330 lines
7.9 KiB
C
Raw Blame History

/* $NetBSD: utmpentry.c,v 1.21 2019/10/05 23:35:57 mrg Exp $ */
/*-
* Copyright (c) 2002 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Christos Zoulas.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#include <sys/cdefs.h>
#ifndef lint
__RCSID("$NetBSD: utmpentry.c,v 1.21 2019/10/05 23:35:57 mrg Exp $");
#endif
#include <sys/stat.h>
#include <time.h>
#include <string.h>
#include <err.h>
#include <stdlib.h>
#ifdef SUPPORT_UTMP
#include <utmp.h>
#endif
#ifdef SUPPORT_UTMPX
#include <utmpx.h>
#endif
#include "utmpentry.h"
/* Fail the compile if x is not true, by constructing an illegal type. */
#define COMPILE_ASSERT(x) /*LINTED null effect */ \
((void)sizeof(struct { unsigned : ((x) ? 1 : -1); }))
#ifdef SUPPORT_UTMP
static void getentry(struct utmpentry *, struct utmp *);
static struct timespec utmptime = {0, 0};
#endif
#ifdef SUPPORT_UTMPX
static void getentryx(struct utmpentry *, struct utmpx *);
static struct timespec utmpxtime = {0, 0};
#endif
#if defined(SUPPORT_UTMPX) || defined(SUPPORT_UTMP)
static int setup(const char *);
static void adjust_size(struct utmpentry *e);
#endif
size_t maxname = 8, maxline = 8, maxhost = 16;
int etype = 1 << USER_PROCESS;
static size_t numutmp = 0;
static struct utmpentry *ehead;
#if defined(SUPPORT_UTMPX) || defined(SUPPORT_UTMP)
static void
adjust_size(struct utmpentry *e)
{
size_t max;
if ((max = strlen(e->name)) > maxname)
maxname = max;
if ((max = strlen(e->line)) > maxline)
maxline = max;
if ((max = strlen(e->host)) > maxhost)
maxhost = max;
}
static int
setup(const char *fname)
{
int what = 3;
struct stat st;
const char *sfname;
if (fname == NULL) {
#ifdef SUPPORT_UTMPX
setutxent();
#endif
#ifdef SUPPORT_UTMP
setutent();
#endif
} else {
size_t len = strlen(fname);
if (len == 0)
errx(1, "Filename cannot be 0 length.");
what = fname[len - 1] == 'x' ? 1 : 2;
if (what == 1) {
#ifdef SUPPORT_UTMPX
if (utmpxname(fname) == 0)
warnx("Cannot set utmpx file to `%s'",
fname);
#else
warnx("utmpx support not compiled in");
#endif
} else {
#ifdef SUPPORT_UTMP
if (utmpname(fname) == 0)
warnx("Cannot set utmp file to `%s'",
fname);
#else
warnx("utmp support not compiled in");
#endif
}
}
#ifdef SUPPORT_UTMPX
if (what & 1) {
sfname = fname ? fname : _PATH_UTMPX;
if (stat(sfname, &st) == -1) {
warn("Cannot stat `%s'", sfname);
what &= ~1;
} else {
if (timespeccmp(&st.st_mtimespec, &utmpxtime, >))
utmpxtime = st.st_mtimespec;
else
what &= ~1;
}
}
#endif
#ifdef SUPPORT_UTMP
if (what & 2) {
sfname = fname ? fname : _PATH_UTMP;
if (stat(sfname, &st) == -1) {
warn("Cannot stat `%s'", sfname);
what &= ~2;
} else {
if (timespeccmp(&st.st_mtimespec, &utmptime, >))
utmptime = st.st_mtimespec;
else
what &= ~2;
}
}
#endif
return what;
}
#endif
void
endutentries(void)
{
struct utmpentry *ep;
#ifdef SUPPORT_UTMP
timespecclear(&utmptime);
#endif
#ifdef SUPPORT_UTMPX
timespecclear(&utmpxtime);
#endif
ep = ehead;
while (ep) {
struct utmpentry *sep = ep;
ep = ep->next;
free(sep);
}
ehead = NULL;
numutmp = 0;
}
size_t
getutentries(const char *fname, struct utmpentry **epp)
{
#ifdef SUPPORT_UTMPX
struct utmpx *utx;
#endif
#ifdef SUPPORT_UTMP
struct utmp *ut;
#endif
#if defined(SUPPORT_UTMP) || defined(SUPPORT_UTMPX)
struct utmpentry *ep;
int what = setup(fname);
struct utmpentry **nextp = &ehead;
switch (what) {
case 0:
/* No updates */
*epp = ehead;
return numutmp;
default:
/* Need to re-scan */
ehead = NULL;
numutmp = 0;
}
#endif
#ifdef SUPPORT_UTMPX
while ((what & 1) && (utx = getutxent()) != NULL) {
if (fname == NULL && ((1 << utx->ut_type) & etype) == 0)
continue;
if ((ep = calloc(1, sizeof(struct utmpentry))) == NULL) {
warn(NULL);
return 0;
}
getentryx(ep, utx);
*nextp = ep;
nextp = &(ep->next);
}
#endif
#ifdef SUPPORT_UTMP
if ((etype & (1 << USER_PROCESS)) != 0) {
while ((what & 2) && (ut = getutent()) != NULL) {
if (fname == NULL && (*ut->ut_name == '\0' ||
*ut->ut_line == '\0'))
continue;
/* Don't process entries that we have utmpx for */
for (ep = ehead; ep != NULL; ep = ep->next) {
if (strncmp(ep->line, ut->ut_line,
sizeof(ut->ut_line)) == 0)
break;
}
if (ep != NULL)
continue;
if ((ep = calloc(1, sizeof(*ep))) == NULL) {
warn(NULL);
return 0;
}
getentry(ep, ut);
*nextp = ep;
nextp = &(ep->next);
}
}
#endif
numutmp = 0;
#if defined(SUPPORT_UTMP) || defined(SUPPORT_UTMPX)
if (ehead != NULL) {
struct utmpentry *from = ehead, *save;
ehead = NULL;
while (from != NULL) {
for (nextp = &ehead;
(*nextp) && strcmp(from->line, (*nextp)->line) > 0;
nextp = &(*nextp)->next)
continue;
save = from;
from = from->next;
save->next = *nextp;
*nextp = save;
numutmp++;
}
}
*epp = ehead;
return numutmp;
#else
*epp = NULL;
return 0;
#endif
}
#ifdef SUPPORT_UTMP
static void
getentry(struct utmpentry *e, struct utmp *up)
{
COMPILE_ASSERT(sizeof(e->name) > sizeof(up->ut_name));
COMPILE_ASSERT(sizeof(e->line) > sizeof(up->ut_line));
COMPILE_ASSERT(sizeof(e->host) > sizeof(up->ut_host));
/*
* e has just been calloc'd. We don't need to clear it or
* append null-terminators, because its length is strictly
* greater than the source string. Use memcpy to _read_
* up->ut_* because they may not be terminated. For this
* reason we use the size of the _source_ as the length
* argument.
*/
memcpy(e->name, up->ut_name, sizeof(up->ut_name));
memcpy(e->line, up->ut_line, sizeof(up->ut_line));
memcpy(e->host, up->ut_host, sizeof(up->ut_host));
e->tv.tv_sec = up->ut_time;
e->tv.tv_usec = 0;
e->pid = 0;
e->term = 0;
e->exit = 0;
e->sess = 0;
e->type = USER_PROCESS;
adjust_size(e);
}
#endif
#ifdef SUPPORT_UTMPX
static void
getentryx(struct utmpentry *e, struct utmpx *up)
{
COMPILE_ASSERT(sizeof(e->name) > sizeof(up->ut_name));
COMPILE_ASSERT(sizeof(e->line) > sizeof(up->ut_line));
COMPILE_ASSERT(sizeof(e->host) > sizeof(up->ut_host));
/*
* e has just been calloc'd. We don't need to clear it or
* append null-terminators, because its length is strictly
* greater than the source string. Use memcpy to _read_
* up->ut_* because they may not be terminated. For this
* reason we use the size of the _source_ as the length
* argument.
*/
memcpy(e->name, up->ut_name, sizeof(up->ut_name));
memcpy(e->line, up->ut_line, sizeof(up->ut_line));
memcpy(e->host, up->ut_host, sizeof(up->ut_host));
e->tv = up->ut_tv;
e->pid = up->ut_pid;
e->term = up->ut_exit.e_termination;
e->exit = up->ut_exit.e_exit;
e->sess = up->ut_session;
e->type = up->ut_type;
adjust_size(e);
}
#endif
Reference in New Issue View Git Blame Copy Permalink