* Copyright (c) 1987, 1993, 1994

/* $NetBSD: want.c,v 1.17 2012/03/15 03:04:05 dholland Exp $ */

/*
* Copyright (c) 1987, 1993, 1994
* The Regents of the University of California. All rights reserved.
*
* 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.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
*/
static struct utmp *buf;
static time_t seentime;

static void onintr(int);
static int want(struct utmp *, int);
static const char *gethost(struct utmp *, const char *, int);

static const char *
/*ARGSUSED*/
gethost(struct utmp *ut, const char *host, int numeric)
{
#if HAS_UT_SS == 0
return numeric ? "" : host;
#else
if (numeric) {
static char hbuf[512];
hbuf[0] = '\0';
(void)sockaddr_snprintf(hbuf, sizeof(hbuf), "%a",
(struct sockaddr *)&ut->ut_ss);
return hbuf;
} else
return host;
#endif
}

#define NULTERM(what) \
if (check ## what) \
(void)strlcpy(what ## p = what ## buf, bp->ut_ ## what, \
sizeof(what ## buf)); \
else \
what ## p = bp->ut_ ## what

/*
* wtmp --
* read through the wtmp file
*/
static void
wtmp(const char *file, int namesz, int linesz, int hostsz, int numeric)
{
struct utmp *bp; /* current structure */
TTY *T; /* tty list entry */
struct stat stb; /* stat of file for sz */
off_t offset;
int wfd;
char *ct;
const char *crmsg;
size_t len = sizeof(*buf) * MAXUTMP;
char namebuf[sizeof(bp->ut_name) + 1], *namep;
char linebuf[sizeof(bp->ut_line) + 1], *linep;
char hostbuf[sizeof(bp->ut_host) + 1], *hostp;
int checkname = namesz > (int)sizeof(bp->ut_name);
int checkline = linesz > (int)sizeof(bp->ut_line);
int checkhost = hostsz > (int)sizeof(bp->ut_host);

if ((buf = malloc(len)) == NULL)
err(EXIT_FAILURE, "Cannot allocate utmp buffer");

crmsg = NULL;

if (!strcmp(file, "-")) {
wfd = STDIN_FILENO;
file = "<stdin>";
} else if ((wfd = open(file, O_RDONLY, 0)) < 0) {
err(EXIT_FAILURE, "%s", file);
}

if (lseek(wfd, 0, SEEK_CUR) < 0) {
const char *dir;
char *tfile;
int tempfd;
ssize_t tlen;

if (ESPIPE != errno) {
err(EXIT_FAILURE, "lseek");
}
dir = getenv("TMPDIR");
if (asprintf(&tfile, "%s/last.XXXXXX", dir ? dir : _PATH_TMP) == -1)
err(EXIT_FAILURE, "asprintf");
tempfd = mkstemp(tfile);
if (tempfd < 0) {
err(EXIT_FAILURE, "mkstemp");
}
unlink(tfile);
for (;;) {
tlen = read(wfd, buf, len);
if (tlen < 0) {
err(1, "%s: read", file);
}
if (tlen == 0) {
break;
}
if (write(tempfd, buf, tlen) != tlen) {
err(1, "%s: write", tfile);
}
}
wfd = tempfd;
}

if (fstat(wfd, &stb) == -1)
err(EXIT_FAILURE, "%s: fstat", file);
if (!S_ISREG(stb.st_mode))
errx(EXIT_FAILURE, "%s: Not a regular file", file);

seentime = stb.st_mtime;
(void)signal(SIGINT, onintr);
(void)signal(SIGQUIT, onintr);

offset = stb.st_size;
/* Ignore trailing garbage or partial record */
offset -= offset % (off_t) sizeof(*buf);

while (offset >= (off_t) sizeof(*buf)) {
ssize_t ret, i;
size_t size;

size = MIN((off_t)len, offset);
offset -= size; /* Always a multiple of sizeof(*buf) */
ret = pread(wfd, buf, size, offset);
if (ret < 0) {
err(EXIT_FAILURE, "%s: pread", file);
} else if ((size_t) ret < size) {
err(EXIT_FAILURE, "%s: Unexpected end of file", file);
}

for (i = ret / sizeof(*buf) - 1; i >= 0; i--) {
bp = &buf[i];

NULTERM(name);
NULTERM(line);
NULTERM(host);

seentime = bp->ut_timefld;

/*
* if the terminal line is '~', the machine stopped.
* see utmp(5) for more info.
*/
if (linep[0] == '~' && !linep[1]) {
/* everybody just logged out */
for (T = ttylist; T; T = T->next)
T->logout = -bp->ut_timefld;
currentout = -bp->ut_timefld;
crmsg = strncmp(namep, "shutdown",
namesz) ? "crash" : "shutdown";
if (want(bp, NO)) {
ct = fmttime(bp->ut_timefld, fulltime);
printf("%-*.*s %-*.*s %-*.*s %s\n",
namesz, namesz, namep,
linesz, linesz, linep,
hostsz, hostsz,
gethost(bp, hostp, numeric), ct);
if (maxrec != -1 && !--maxrec)
return;
}
continue;
}
/*
* if the line is '{' or '|', date got set; see
* utmp(5) for more info.
*/
if ((linep[0] == '{' || linep[0] == '|') && !linep[1]) {
if (want(bp, NO)) {
ct = fmttime(bp->ut_timefld, fulltime);
printf("%-*.*s %-*.*s %-*.*s %s\n",
namesz, namesz, namep,
linesz, linesz, linep,
hostsz, hostsz,
gethost(bp, hostp, numeric),
ct);
if (maxrec && !--maxrec)
return;
}
continue;
}
/* find associated tty */
for (T = ttylist;; T = T->next) {
if (!T) {
/* add new one */
T = addtty(linep);
break;
}
if (!strncmp(T->tty, linep, LINESIZE))
break;
}
if (TYPE(bp) == SIGNATURE)
continue;
if (namep[0] && want(bp, YES)) {
ct = fmttime(bp->ut_timefld, fulltime);
printf("%-*.*s %-*.*s %-*.*s %s ",
namesz, namesz, namep,
linesz, linesz, linep,
hostsz, hostsz,
gethost(bp, hostp, numeric),
ct);
if (!T->logout)
puts(" still logged in");
else {
time_t delta; /* time difference */

if (T->logout < 0) {
T->logout = -T->logout;
printf("- %s", crmsg);
}
else
printf("- %s",
fmttime(T->logout,
fulltime | TIMEONLY));
delta = T->logout - bp->ut_timefld;
if (delta < SECSPERDAY)
printf(" (%s)\n",
fmttime(delta,
fulltime | TIMEONLY | GMT));
else
printf(" (%lld+%s)\n",
(long long)
delta / SECSPERDAY,
fmttime(delta,
fulltime | TIMEONLY | GMT));
}
if (maxrec != -1 && !--maxrec)
return;
}
T->logout = bp->ut_timefld;
}
}
fulltime = 1; /* show full time */
crmsg = fmttime(seentime, FULLTIME);
if ((ct = strrchr(file, '/')) != NULL)
ct++;
printf("\n%s begins %s\n", ct ? ct : file, crmsg);
}

/*
* want --
* see if want this entry
*/
static int
want(struct utmp *bp, int check)
{
ARG *step;

if (check) {
/*
* when uucp and ftp log in over a network, the entry in
* the utmp file is the name plus their process id. See
* etc/ftpd.c and usr.bin/uucp/uucpd.c for more information.
*/
if (!strncmp(bp->ut_line, "ftp", sizeof("ftp") - 1))
bp->ut_line[3] = '\0';
else if (!strncmp(bp->ut_line, "uucp", sizeof("uucp") - 1))
bp->ut_line[4] = '\0';
}
if (!arglist)
return (YES);

for (step = arglist; step; step = step->next)
switch(step->type) {
case HOST_TYPE:
if (!strncasecmp(step->name, bp->ut_host, HOSTSIZE))
return (YES);
break;
case TTY_TYPE:
if (!strncmp(step->name, bp->ut_line, LINESIZE))
return (YES);
break;
case USER_TYPE:
if (!strncmp(step->name, bp->ut_name, NAMESIZE))
return (YES);
break;
}
return (NO);
}

/*
* onintr --
* on interrupt, we inform the user how far we've gotten
*/
static void
onintr(int signo)
{
/* FIXME: None of this is allowed in a signal handler */
printf("\ninterrupted %s\n", fmttime(seentime, FULLTIME));
if (signo == SIGINT) {
(void)raise_default_signal(signo);
exit(EXIT_FAILURE);
}
(void)fflush(stdout); /* fix required for rsh */
}