procps/w.c
Sami Kerola ddd15211e0 w: use utmp definitions to determine array sizes
Signed-off-by: Sami Kerola <kerolasa@iki.fi>

Conflicts:

	w.c
2012-03-04 08:20:39 +11:00

479 lines
12 KiB
C

/*
* w - show what logged in users are doing.
*
* Almost entirely rewritten from scratch by Charles Blake circa
* June 1996. Some vestigal traces of the original may exist.
* That was done in 1993 by Larry Greenfield with some fixes by
* Michael K. Johnson.
*
* Changes by Albert Cahalan, 2002.
*
* This library 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.
*
* This library 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 this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "c.h"
#include "nls.h"
#include "proc/devname.h"
#include "proc/escape.h"
#include "proc/procps.h"
#include "proc/readproc.h"
#include "proc/sysinfo.h"
#include "proc/version.h"
#include "proc/whattime.h"
#include <ctype.h>
#include <errno.h>
#include <fcntl.h>
#include <getopt.h>
#include <limits.h>
#include <locale.h>
#include <locale.h>
#include <pwd.h>
#include <pwd.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/ioctl.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <termios.h>
#include <time.h>
#include <unistd.h>
#include <utmp.h>
static int ignoreuser = 0; /* for '-u' */
static int oldstyle = 0; /* for '-o' */
static proc_t **procs; /* our snapshot of the process table */
typedef struct utmp utmp_t;
#ifdef W_SHOWFROM
# define FROM_STRING "on"
#else
# define FROM_STRING "off"
#endif
/* Arbitary setting, not too big for the screen, max host size */
#define HOSTSZ 40
/*
* This routine is careful since some programs leave utmp strings
* unprintable. Always outputs at least 16 chars padded with
* spaces on the right if necessary.
*/
static void print_host(const char *restrict host, int len, const int fromlen)
{
const char *last;
int width = 0;
if (len > fromlen)
len = fromlen;
last = host + len;
for (; host < last; host++) {
if (isprint(*host) && *host != ' ') {
fputc(*host, stdout);
++width;
} else {
fputc('-', stdout);
++width;
break;
}
}
/*
* space-fill, and a '-' too if needed to ensure the
* column exists
*/
while (width++ < fromlen)
fputc(' ', stdout);
}
/* compact 7 char format for time intervals (belongs in libproc?) */
static void print_time_ival7(time_t t, int centi_sec, FILE * fout)
{
if ((long)t < (long)0) {
/* system clock changed? */
printf(" ? ");
return;
}
if (oldstyle) {
if (t >= 48 * 60 * 60)
/* > 2 days */
fprintf(fout, _(" %2ludays"), t / (24 * 60 * 60));
else if (t >= 60 * 60)
/* > 1 hour */
fprintf(fout, " %2lu:%02u ", t / (60 * 60),
(unsigned)((t / 60) % 60));
else if (t > 60)
/* > 1 minute */
fprintf(fout, _(" %2lu:%02um"), t / 60, (unsigned)t % 60);
else
fprintf(fout, " ");
} else {
if (t >= 48 * 60 * 60)
/* 2 days or more */
fprintf(fout, _(" %2ludays"), t / (24 * 60 * 60));
else if (t >= 60 * 60)
/* 1 hour or more */
fprintf(fout, _(" %2lu:%02um"), t / (60 * 60),
(unsigned)((t / 60) % 60));
else if (t > 60)
/* 1 minute or more */
fprintf(fout, " %2lu:%02u ", t / 60, (unsigned)t % 60);
else
fprintf(fout, _(" %2lu.%02us"), t, centi_sec);
}
}
/* stat the device file to get an idle time */
static time_t idletime(const char *restrict const tty)
{
struct stat sbuf;
if (stat(tty, &sbuf) != 0)
return 0;
return time(NULL) - sbuf.st_atime;
}
/* 7 character formatted login time */
static void print_logintime(time_t logt, FILE * fout)
{
/* FIXME: make use of locale, remember strftime() */
char weekday[][4] = {
"Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"
};
char month[][4] = {
"Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug",
"Sep", "Oct", "Nov", "Dec"
};
time_t curt;
struct tm *logtm, *curtm;
int today;
curt = time(NULL);
curtm = localtime(&curt);
/* localtime returns a pointer to static memory */
today = curtm->tm_yday;
logtm = localtime(&logt);
if (curt - logt > 12 * 60 * 60 && logtm->tm_yday != today) {
if (curt - logt > 6 * 24 * 60 * 60)
fprintf(fout, " %02d%3s%02d", logtm->tm_mday,
month[logtm->tm_mon], logtm->tm_year % 100);
else
fprintf(fout, " %3s%02d ", weekday[logtm->tm_wday],
logtm->tm_hour);
} else {
fprintf(fout, " %02d:%02d ", logtm->tm_hour, logtm->tm_min);
}
}
/*
* This function scans the process table accumulating total cpu
* times for any processes "associated" with this login session.
* It also searches for the "best" process to report as "(w)hat"
* the user for that login session is doing currently. This the
* essential core of 'w'.
*/
static const proc_t *getproc(const utmp_t * restrict const u,
const char *restrict const tty,
unsigned long long *restrict const jcpu,
int *restrict const found_utpid)
{
int line;
proc_t **pptr = procs;
const proc_t *best = NULL;
const proc_t *secondbest = NULL;
unsigned uid = ~0U;
*found_utpid = 0;
if (!ignoreuser) {
char buf[UT_NAMESIZE + 1];
/* pointer to static data */
struct passwd *passwd_data;
strncpy(buf, u->ut_user, UT_NAMESIZE);
buf[UT_NAMESIZE] = '\0';
passwd_data = getpwnam(buf);
if (!passwd_data)
return NULL;
uid = passwd_data->pw_uid;
/* OK to have passwd_data go out of scope here */
}
line = tty_to_dev(tty);
*jcpu = 0;
for (; *pptr; pptr++) {
const proc_t *restrict const tmp = *pptr;
if (unlikely(tmp->tgid == u->ut_pid)) {
*found_utpid = 1;
best = tmp;
}
if (tmp->tty != line)
continue;
(*jcpu) += tmp->utime + tmp->stime;
secondbest = tmp;
/* same time-logic here as for "best" below */
if (!(secondbest && tmp->start_time <= secondbest->start_time)) {
secondbest = tmp;
}
if (!ignoreuser && uid != tmp->euid && uid != tmp->ruid)
continue;
if (tmp->pgrp != tmp->tpgid)
continue;
if (best && tmp->start_time <= best->start_time)
continue;
best = tmp;
}
return best ? best : secondbest;
}
static void showinfo(utmp_t * u, int formtype, int maxcmd, int from,
const int userlen, const int fromlen)
{
unsigned long long jcpu;
int ut_pid_found;
unsigned i;
char uname[UT_NAMESIZE + 1] = "", tty[5 + UT_LINESIZE + 1] = "/dev/";
const proc_t *best;
for (i = 0; i < sizeof(u->ut_line); i++)
/* clean up tty if garbled */
if (isalnum(u->ut_line[i]) || (u->ut_line[i] == '/'))
tty[i + 5] = u->ut_line[i];
else
tty[i + 5] = '\0';
best = getproc(u, tty + 5, &jcpu, &ut_pid_found);
/*
* just skip if stale utmp entry (i.e. login proc doesn't
* exist). If there is a desire a cmdline flag could be
* added to optionally show it with a prefix of (stale)
* in front of cmd or something like that.
*/
if (!ut_pid_found)
return;
/* force NUL term for printf */
strncpy(uname, u->ut_user, UT_NAMESIZE);
if (formtype) {
printf("%-*.*s%-9.8s", userlen + 1, userlen, uname, u->ut_line);
if (from)
print_host(u->ut_host, sizeof u->ut_host, fromlen);
print_logintime(u->ut_time, stdout);
if (*u->ut_line == ':')
/* idle unknown for xdm logins */
printf(" ?xdm? ");
else
print_time_ival7(idletime(tty), 0, stdout);
print_time_ival7(jcpu / Hertz, (jcpu % Hertz) * (100. / Hertz),
stdout);
if (best) {
unsigned long long pcpu = best->utime + best->stime;
print_time_ival7(pcpu / Hertz,
(pcpu % Hertz) * (100. / Hertz),
stdout);
} else
printf(" ? ");
} else {
printf("%-*.*s%-9.8s", userlen + 1, userlen, u->ut_user,
u->ut_line);
if (from)
print_host(u->ut_host, sizeof u->ut_host, fromlen);
if (*u->ut_line == ':')
/* idle unknown for xdm logins */
printf(" ?xdm? ");
else
print_time_ival7(idletime(tty), 0, stdout);
}
fputs(" ", stdout);
if (likely(best)) {
char cmdbuf[512];
escape_command(cmdbuf, best, sizeof cmdbuf, &maxcmd, ESC_ARGS);
fputs(cmdbuf, stdout);
} else {
printf("-");
}
fputc('\n', stdout);
}
static void __attribute__ ((__noreturn__))
usage(FILE * out)
{
fputs(USAGE_HEADER, out);
fprintf(out,
_(" %s [options]\n"), program_invocation_short_name);
fputs(USAGE_OPTIONS, out);
fputs(_(" -h, --no-header do not print header\n"
" -u, --no-current ignore current process username\n"
" -s, --short short format\n"
" -f, --from show remote hostname field\n"
" -o, --old-style old style output\n"), out);
fputs(USAGE_SEPARATOR, out);
fputs(_(" --help display this help and exit\n"), out);
fputs(USAGE_VERSION, out);
fprintf(out, USAGE_MAN_TAIL("w(1)"));
exit(out == stderr ? EXIT_FAILURE : EXIT_SUCCESS);
}
int main(int argc, char **argv)
{
char *user = NULL, *p;
utmp_t *u;
struct winsize win;
int header = 1, longform = 1, from = 1, maxcmd = 80, ch;
int userlen = 8;
int fromlen = 16;
char *env_var;
enum {
HELP_OPTION = CHAR_MAX + 1
};
static const struct option longopts[] = {
{"no-header", no_argument, NULL, 'h'},
{"no-current", no_argument, NULL, 'u'},
{"sort", no_argument, NULL, 's'},
{"from", no_argument, NULL, 'f'},
{"old-style", no_argument, NULL, 'o'},
{"help", no_argument, NULL, HELP_OPTION},
{"version", no_argument, NULL, 'V'},
{NULL, 0, NULL, 0}
};
program_invocation_name = program_invocation_short_name;
setlocale (LC_ALL, "");
bindtextdomain(PACKAGE, LOCALEDIR);
textdomain(PACKAGE);
#ifndef W_SHOWFROM
from = 0;
#endif
while ((ch =
getopt_long(argc, argv, "husfoV", longopts, NULL)) != -1)
switch (ch) {
case 'h':
header = 0;
break;
case 'l':
longform = 1;
break;
case 's':
longform = 0;
break;
case 'f':
from = !from;
break;
case 'V':
printf(PROCPS_NG_VERSION);
exit(0);
case 'u':
ignoreuser = 1;
break;
case 'o':
oldstyle = 1;
break;
case HELP_OPTION:
usage(stdout);
default:
usage(stderr);
}
if ((argv[optind]))
user = (argv[optind]);
/* Get user field length from environment */
if ((env_var = getenv("PROCPS_USERLEN")) != NULL) {
userlen = atoi(env_var);
if (userlen < 8 || userlen > UT_NAMESIZE) {
xwarnx
(_("User length environment PROCPS_USERLEN must be between 8 and %zu, ignoring.\n"),
UT_NAMESIZE);
userlen = 8;
}
}
/* Get from field length from environment */
if ((env_var = getenv("PROCPS_FROMLEN")) != NULL) {
fromlen = atoi(env_var);
if (fromlen < 8 || fromlen > HOSTSZ) {
xwarnx
(_("from length environment PROCPS_FROMLEN must be between 8 and %d, ignoring\n"),
HOSTSZ);
fromlen = 16;
}
}
if (ioctl(STDOUT_FILENO, TIOCGWINSZ, &win) != -1 && win.ws_col > 0)
maxcmd = win.ws_col;
else if ((p = getenv("COLUMNS")))
maxcmd = atoi(p);
else
maxcmd = 80;
if (maxcmd < 71)
xerrx(EXIT_FAILURE, _("%d column window is too narrow"), maxcmd);
maxcmd -= 21 + userlen + (from ? fromlen : 0) + (longform ? 20 : 0);
if (maxcmd < 3)
xwarnx(_("warning: screen width %d suboptimal"), win.ws_col);
procs = readproctab(PROC_FILLCOM | PROC_FILLUSR | PROC_FILLSTAT);
if (header) {
/* print uptime and headers */
print_uptime();
/* Translation Hint: Following five uppercase messages are
* headers. Try to keep alignment intact. */
printf(_("%-*s TTY "), userlen, _("USER"));
if (from)
printf(_("FROM "));
if (longform)
printf(_(" LOGIN@ IDLE JCPU PCPU WHAT\n"));
else
printf(_(" IDLE WHAT\n"));
}
utmpname(UTMP_FILE);
setutent();
if (user) {
for (;;) {
u = getutent();
if (unlikely(!u))
break;
if (u->ut_type != USER_PROCESS)
continue;
if (!strncmp(u->ut_user, user, UT_NAMESIZE))
showinfo(u, longform, maxcmd, from, userlen,
fromlen);
}
} else {
for (;;) {
u = getutent();
if (unlikely(!u))
break;
if (u->ut_type != USER_PROCESS)
continue;
if (*u->ut_user)
showinfo(u, longform, maxcmd, from, userlen,
fromlen);
}
}
endutent();
return EXIT_SUCCESS;
}