procps/w.c
Craig Small 99bebff06a w: use environment to set user and from/host column widths
A patch from Debian.

Bug-Debian: http://bugs.debian.org/396423
Bug-Debian: http://bugs.debian.org/341439
Backported-by: Sami Kerola <kerolasa@iki.fi>
2011-12-18 22:57:35 +11:00

346 lines
10 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.
*/
#include "proc/version.h"
#include "proc/whattime.h"
#include "proc/readproc.h"
#include "proc/devname.h"
#include "proc/procps.h"
#include "proc/sysinfo.h"
#include "proc/escape.h"
#include <ctype.h>
#include <errno.h>
#include <fcntl.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 <pwd.h>
#include <time.h>
#include <unistd.h>
#include <utmp.h>
#include <locale.h>
#include <termios.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
/* Uh... same thing as UT_NAMESIZE */
#define USERSZ (sizeof u->ut_user)
/* 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 fromlen 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 {
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 */
fprintf(fout, " %2ludays", t/(24*60*60));
else if (t >= 60*60) /* > 1 hour */
fprintf(fout, " %2lu:%02um", t/(60*60), (unsigned) ((t/60)%60));
else if (t > 60) /* > 1 minute */
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) {
char weekday[][4] = { "Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat" },
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];
struct passwd *passwd_data; /* pointer to static 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;
}
/***** showinfo */
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[USERSZ + 1] = "",
tty[5 + sizeof u->ut_line + 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;
strncpy(uname, u->ut_user, USERSZ); /* force NUL term for printf */
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);
}
/***** main */
int main(int argc, char **argv) {
char *user = NULL, *p;
utmp_t *u;
struct winsize win;
int header=1, longform=1, from=1, args, maxcmd=80, ch;
int userlen = 8;
int fromlen = 16;
char *env_var;
#ifndef W_SHOWFROM
from = 0;
#endif
setlocale(LC_ALL, "");
for (args=0; (ch = getopt(argc, argv, "hlusfVo")) != EOF; args++)
switch (ch) {
case 'h': header = 0; break;
case 'l': longform = 1; break;
case 's': longform = 0; break;
case 'f': from = !from; break;
case 'V': display_version(); exit(0);
case 'u': ignoreuser = 1; break;
case 'o': oldstyle = 1; break;
default:
printf("usage: w -hlsufV [user]\n"
" -h skip header\n"
" -l long listing (default)\n"
" -s short listing\n"
" -u ignore uid of processes\n"
" -f toggle FROM field (default %s)\n"
" -o old-style output\n"
" -V display version\n", FROM_STRING);
exit(1);
}
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 > USERSZ) {
fprintf(stderr, "User length environment PROCPS_USERLEN must be between 8 and %d, ignoring.\n", USERSZ);
userlen=8;
}
}
/* Get from field length from environment */
if ( (env_var = getenv("PROCPS_FROMLEN")) != NULL) {
fromlen = atoi(env_var);
if (fromlen < 8 || fromlen > HOSTSZ) {
fprintf(stderr, "From length environment PROCPS_FROMLEN must be between 8 and %d, ignoring.\n", HOSTSZ);
fromlen=16;
}
}
if (ioctl(1, 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) {
fprintf(stderr, "%d column window is too narrow\n", maxcmd);
exit(1);
}
maxcmd -= 21 + userlen + (from ? fromlen : 0) + (longform ? 20 : 0);
if (maxcmd < 3)
fprintf(stderr, "warning: screen width %d suboptimal.\n", win.ws_col);
procs = readproctab(PROC_FILLCOM | PROC_FILLUSR | PROC_FILLSTAT);
if (header) { /* print uptime and headers */
print_uptime();
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, USERSZ)) 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 0;
}