freebsd-src/usr.bin/who/who.c
Peter Wemm 10ebb45ae0 Fix a warning that showed up on 64 bit systems. It was actually a real
bug that had been swept under the carpet.
2003-10-26 05:05:48 +00:00

295 lines
6.5 KiB
C

/*-
* Copyright (c) 2002 Tim J. Robbins.
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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>
__FBSDID("$FreeBSD$");
#include <sys/types.h>
#include <sys/ioctl.h>
#include <sys/stat.h>
#include <err.h>
#include <errno.h>
#include <langinfo.h>
#include <limits.h>
#include <locale.h>
#include <paths.h>
#include <pwd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <timeconv.h>
#include <unistd.h>
#include <utmp.h>
static void heading(void);
static void process_utmp(FILE *);
static void quick(FILE *);
static void row(struct utmp *);
static int ttywidth(void);
static void usage(void);
static void whoami(FILE *);
static int Hflag; /* Write column headings */
static int mflag; /* Show info about current terminal */
static int qflag; /* "Quick" mode */
static int sflag; /* Show name, line, time */
static int Tflag; /* Show terminal state */
static int uflag; /* Show idle time */
int
main(int argc, char *argv[])
{
int ch;
const char *file;
FILE *fp;
setlocale(LC_TIME, "");
while ((ch = getopt(argc, argv, "HTmqsu")) != -1) {
switch (ch) {
case 'H': /* Write column headings */
Hflag = 1;
break;
case 'T': /* Show terminal state */
Tflag = 1;
break;
case 'm': /* Show info about current terminal */
mflag = 1;
break;
case 'q': /* "Quick" mode */
qflag = 1;
break;
case 's': /* Show name, line, time */
sflag = 1;
break;
case 'u': /* Show idle time */
uflag = 1;
break;
default:
usage();
/*NOTREACHED*/
}
}
argc -= optind;
argv += optind;
if (argc >= 2 && strcmp(argv[0], "am") == 0 &&
(strcmp(argv[1], "i") == 0 || strcmp(argv[1], "I") == 0)) {
/* "who am i" or "who am I", equivalent to -m */
mflag = 1;
argc -= 2;
argv += 2;
}
if (argc > 1)
usage();
if (*argv != NULL)
file = *argv;
else
file = _PATH_UTMP;
if ((fp = fopen(file, "r")) == NULL)
err(1, "%s", file);
if (qflag)
quick(fp);
else {
if (sflag)
Tflag = uflag = 0;
if (Hflag)
heading();
if (mflag)
whoami(fp);
else
process_utmp(fp);
}
fclose(fp);
exit(0);
}
static void
usage(void)
{
fprintf(stderr, "usage: who [-HmqsTu] [am I] [file]\n");
exit(1);
}
static void
heading(void)
{
printf("%-*s ", UT_NAMESIZE, "NAME");
if (Tflag)
printf("S ");
printf("%-*s ", UT_LINESIZE, "LINE");
printf("%-*s ", 12, "TIME");
if (uflag)
printf("IDLE ");
printf("%-*s", UT_HOSTSIZE, "FROM");
putchar('\n');
}
static void
row(struct utmp *ut)
{
char buf[80], tty[sizeof(_PATH_DEV) + UT_LINESIZE];
struct stat sb;
time_t idle, t;
static int d_first = -1;
struct tm *tm;
char state;
if (d_first < 0)
d_first = (*nl_langinfo(D_MD_ORDER) == 'd');
if (Tflag || uflag) {
snprintf(tty, sizeof(tty), "%s%.*s", _PATH_DEV,
UT_LINESIZE, ut->ut_line);
state = '?';
idle = 0;
if (stat(tty, &sb) == 0) {
state = sb.st_mode & (S_IWOTH|S_IWGRP) ?
'+' : '-';
idle = time(NULL) - sb.st_mtime;
}
}
printf("%-*.*s ", UT_NAMESIZE, UT_NAMESIZE, ut->ut_name);
if (Tflag)
printf("%c ", state);
printf("%-*.*s ", UT_LINESIZE, UT_LINESIZE, ut->ut_line);
t = _time32_to_time(ut->ut_time);
tm = localtime(&t);
strftime(buf, sizeof(buf), d_first ? "%e %b %R" : "%b %e %R", tm);
printf("%-*s ", 12, buf);
if (uflag) {
if (idle < 60)
printf(" . ");
else if (idle < 24 * 60 * 60)
printf("%02d:%02d ", (int)(idle / 60 / 60),
(int)(idle / 60 % 60));
else
printf(" old ");
}
if (*ut->ut_host != '\0')
printf("(%.*s)", UT_HOSTSIZE, ut->ut_host);
putchar('\n');
}
static void
process_utmp(FILE *fp)
{
struct utmp ut;
while (fread(&ut, sizeof(ut), 1, fp) == 1)
if (*ut.ut_name != '\0')
row(&ut);
}
static void
quick(FILE *fp)
{
struct utmp ut;
int col, ncols, num;
ncols = ttywidth();
col = num = 0;
while (fread(&ut, sizeof(ut), 1, fp) == 1) {
if (*ut.ut_name == '\0')
continue;
printf("%-*.*s", UT_NAMESIZE, UT_NAMESIZE, ut.ut_name);
if (++col < ncols / (UT_NAMESIZE + 1))
putchar(' ');
else {
col = 0;
putchar('\n');
}
num++;
}
if (col != 0)
putchar('\n');
printf("# users = %d\n", num);
}
static void
whoami(FILE *fp)
{
struct utmp ut;
struct passwd *pwd;
const char *name, *p, *tty;
if ((tty = ttyname(STDIN_FILENO)) == NULL)
tty = "tty??";
else if ((p = strrchr(tty, '/')) != NULL)
tty = p + 1;
/* Search utmp for our tty, dump first matching record. */
while (fread(&ut, sizeof(ut), 1, fp) == 1)
if (*ut.ut_name != '\0' && strncmp(ut.ut_line, tty,
UT_LINESIZE) == 0) {
row(&ut);
return;
}
/* Not found; fill the utmp structure with the information we have. */
memset(&ut, 0, sizeof(ut));
if ((pwd = getpwuid(getuid())) != NULL)
name = pwd->pw_name;
else
name = "?";
strncpy(ut.ut_name, name, UT_NAMESIZE);
strncpy(ut.ut_line, tty, UT_LINESIZE);
ut.ut_time = _time_to_time32(time(NULL));
row(&ut);
}
static int
ttywidth(void)
{
struct winsize ws;
long width;
char *cols, *ep;
if ((cols = getenv("COLUMNS")) != NULL && *cols != '\0') {
errno = 0;
width = strtol(cols, &ep, 10);
if (errno || width <= 0 || width > INT_MAX || ep == cols ||
*ep != '\0')
warnx("invalid COLUMNS environment variable ignored");
else
return (width);
}
if (ioctl(STDOUT_FILENO, TIOCGWINSZ, &ws) != -1)
return (ws.ws_col);
return (80);
}