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mirror of https://git.FreeBSD.org/src.git synced 2024-12-20 11:11:24 +00:00
freebsd/contrib/top/top.c
Kris Kennaway 26d889d4ff Don't do unsafe activities inside signal handlers. Just set a flag and
return.

Obtained from:	OpenBSD
Reviewed by:	audit
2001-08-06 03:19:22 +00:00

1035 lines
22 KiB
C

char *copyright =
"Copyright (c) 1984 through 1996, William LeFebvre";
/*
* Top users/processes display for Unix
* Version 3
*
* This program may be freely redistributed,
* but this entire comment MUST remain intact.
*
* Copyright (c) 1984, 1989, William LeFebvre, Rice University
* Copyright (c) 1989, 1990, 1992, William LeFebvre, Northwestern University
*
* $FreeBSD$
*/
/*
* See the file "Changes" for information on version-to-version changes.
*/
/*
* This file contains "main" and other high-level routines.
*/
/*
* The following preprocessor variables, when defined, are used to
* distinguish between different Unix implementations:
*
* SIGHOLD - use SVR4 sighold function when defined
* SIGRELSE - use SVR4 sigrelse function when defined
* FD_SET - macros FD_SET and FD_ZERO are used when defined
*/
#include "os.h"
#include <signal.h>
#include <setjmp.h>
#include <ctype.h>
#include <sys/time.h>
/* includes specific to top */
#include "display.h" /* interface to display package */
#include "screen.h" /* interface to screen package */
#include "top.h"
#include "top.local.h"
#include "boolean.h"
#include "machine.h"
#include "utils.h"
/* Size of the stdio buffer given to stdout */
#define Buffersize 2048
/* The buffer that stdio will use */
char stdoutbuf[Buffersize];
/* build Signal masks */
#define Smask(s) (1 << ((s) - 1))
/* for system errors */
extern int errno;
/* for getopt: */
extern int optind;
extern char *optarg;
/* imported from screen.c */
extern int overstrike;
/* signal handling routines */
sigret_t leave();
sigret_t onalrm();
sigret_t tstop();
#ifdef SIGWINCH
sigret_t winch();
#endif
volatile sig_atomic_t leaveflag;
volatile sig_atomic_t tstopflag;
volatile sig_atomic_t winchflag;
/* internal routines */
void quit();
/* values which need to be accessed by signal handlers */
static int max_topn; /* maximum displayable processes */
/* miscellaneous things */
char *myname = "top";
jmp_buf jmp_int;
/* routines that don't return int */
char *username();
char *ctime();
char *kill_procs();
char *renice_procs();
#ifdef ORDER
extern int (*proc_compares[])();
#else
extern int proc_compare();
#endif
time_t time();
caddr_t get_process_info();
/* different routines for displaying the user's identification */
/* (values assigned to get_userid) */
char *username();
char *itoa7();
/* display routines that need to be predeclared */
int i_loadave();
int u_loadave();
int i_procstates();
int u_procstates();
int i_cpustates();
int u_cpustates();
int i_memory();
int u_memory();
int i_swap();
int u_swap();
int i_message();
int u_message();
int i_header();
int u_header();
int i_process();
int u_process();
/* pointers to display routines */
int (*d_loadave)() = i_loadave;
int (*d_procstates)() = i_procstates;
int (*d_cpustates)() = i_cpustates;
int (*d_memory)() = i_memory;
int (*d_swap)() = i_swap;
int (*d_message)() = i_message;
int (*d_header)() = i_header;
int (*d_process)() = i_process;
main(argc, argv)
int argc;
char *argv[];
{
register int i;
register int active_procs;
register int change;
struct system_info system_info;
struct statics statics;
caddr_t processes;
static char tempbuf1[50];
static char tempbuf2[50];
int old_sigmask; /* only used for BSD-style signals */
int topn = Default_TOPN;
int delay = Default_DELAY;
int displays = 0; /* indicates unspecified */
time_t curr_time;
char *(*get_userid)() = username;
char *uname_field = "USERNAME";
char *header_text;
char *env_top;
char **preset_argv;
int preset_argc = 0;
char **av;
int ac;
char dostates = No;
char do_unames = Yes;
char interactive = Maybe;
char warnings = 0;
#if Default_TOPN == Infinity
char topn_specified = No;
#endif
char ch;
char *iptr;
char no_command = 1;
struct timeval timeout;
struct process_select ps;
#ifdef ORDER
char *order_name = NULL;
int order_index = 0;
#endif
#ifndef FD_SET
/* FD_SET and friends are not present: fake it */
typedef int fd_set;
#define FD_ZERO(x) (*(x) = 0)
#define FD_SET(f, x) (*(x) = f)
#endif
fd_set readfds;
#ifdef ORDER
static char command_chars[] = "\f qh?en#sdkriIuto";
#else
static char command_chars[] = "\f qh?en#sdkriIut";
#endif
/* these defines enumerate the "strchr"s of the commands in command_chars */
#define CMD_redraw 0
#define CMD_update 1
#define CMD_quit 2
#define CMD_help1 3
#define CMD_help2 4
#define CMD_OSLIMIT 4 /* terminals with OS can only handle commands */
#define CMD_errors 5 /* less than or equal to CMD_OSLIMIT */
#define CMD_number1 6
#define CMD_number2 7
#define CMD_delay 8
#define CMD_displays 9
#define CMD_kill 10
#define CMD_renice 11
#define CMD_idletog 12
#define CMD_idletog2 13
#define CMD_user 14
#define CMD_selftog 15
#ifdef ORDER
#define CMD_order 16
#endif
/* set the buffer for stdout */
#ifdef DEBUG
setbuffer(stdout, NULL, 0);
#else
setbuffer(stdout, stdoutbuf, Buffersize);
#endif
/* get our name */
if (argc > 0)
{
if ((myname = strrchr(argv[0], '/')) == 0)
{
myname = argv[0];
}
else
{
myname++;
}
}
/* initialize some selection options */
ps.idle = Yes;
ps.self = -1;
ps.system = No;
ps.uid = -1;
ps.command = NULL;
/* get preset options from the environment */
if ((env_top = getenv("TOP")) != NULL)
{
av = preset_argv = argparse(env_top, &preset_argc);
ac = preset_argc;
/* set the dummy argument to an explanatory message, in case
getopt encounters a bad argument */
preset_argv[0] = "while processing environment";
}
/* process options */
do {
/* if we're done doing the presets, then process the real arguments */
if (preset_argc == 0)
{
ac = argc;
av = argv;
/* this should keep getopt happy... */
optind = 1;
}
while ((i = getopt(ac, av, "SIbinqus:d:U:o:t")) != EOF)
{
switch(i)
{
case 'u': /* toggle uid/username display */
do_unames = !do_unames;
break;
case 'U': /* display only username's processes */
if ((ps.uid = userid(optarg)) == -1)
{
fprintf(stderr, "%s: unknown user\n", optarg);
exit(1);
}
break;
case 'S': /* show system processes */
ps.system = !ps.system;
break;
case 'I': /* show idle processes */
ps.idle = !ps.idle;
break;
case 'i': /* go interactive regardless */
interactive = Yes;
break;
case 'n': /* batch, or non-interactive */
case 'b':
interactive = No;
break;
case 'd': /* number of displays to show */
if ((i = atoiwi(optarg)) == Invalid || i == 0)
{
fprintf(stderr,
"%s: warning: display count should be positive -- option ignored\n",
myname);
warnings++;
}
else
{
displays = i;
}
break;
case 's':
if ((delay = atoi(optarg)) < 0)
{
fprintf(stderr,
"%s: warning: seconds delay should be non-negative -- using default\n",
myname);
delay = Default_DELAY;
warnings++;
}
break;
case 'q': /* be quick about it */
/* only allow this if user is really root */
if (getuid() == 0)
{
/* be very un-nice! */
(void) nice(-20);
}
else
{
fprintf(stderr,
"%s: warning: `-q' option can only be used by root\n",
myname);
warnings++;
}
break;
case 'o': /* select sort order */
#ifdef ORDER
order_name = optarg;
#else
fprintf(stderr,
"%s: this platform does not support arbitrary ordering. Sorry.\n",
myname);
warnings++;
#endif
break;
case 't':
ps.self = (ps.self == -1) ? getpid() : -1;
break;
default:
fprintf(stderr, "\
Top version %s\n\
Usage: %s [-ISbinqut] [-d x] [-s x] [-o field] [-U username] [number]\n",
version_string(), myname);
exit(1);
}
}
/* get count of top processes to display (if any) */
if (optind < ac)
{
if ((topn = atoiwi(av[optind])) == Invalid)
{
fprintf(stderr,
"%s: warning: process display count should be non-negative -- using default\n",
myname);
warnings++;
}
#if Default_TOPN == Infinity
else
{
topn_specified = Yes;
}
#endif
}
/* tricky: remember old value of preset_argc & set preset_argc = 0 */
i = preset_argc;
preset_argc = 0;
/* repeat only if we really did the preset arguments */
} while (i != 0);
/* set constants for username/uid display correctly */
if (!do_unames)
{
uname_field = " UID ";
get_userid = itoa7;
}
/* initialize the kernel memory interface */
if (machine_init(&statics) == -1)
{
exit(1);
}
#ifdef ORDER
/* determine sorting order index, if necessary */
if (order_name != NULL)
{
if ((order_index = string_index(order_name, statics.order_names)) == -1)
{
char **pp;
fprintf(stderr, "%s: '%s' is not a recognized sorting order.\n",
myname, order_name);
fprintf(stderr, "\tTry one of these:");
pp = statics.order_names;
while (*pp != NULL)
{
fprintf(stderr, " %s", *pp++);
}
fputc('\n', stderr);
exit(1);
}
}
#endif
#ifdef no_initialization_needed
/* initialize the hashing stuff */
if (do_unames)
{
init_hash();
}
#endif
/* initialize termcap */
init_termcap(interactive);
/* get the string to use for the process area header */
header_text = format_header(uname_field);
/* initialize display interface */
if ((max_topn = display_init(&statics)) == -1)
{
fprintf(stderr, "%s: can't allocate sufficient memory\n", myname);
exit(4);
}
/* print warning if user requested more processes than we can display */
if (topn > max_topn)
{
fprintf(stderr,
"%s: warning: this terminal can only display %d processes.\n",
myname, max_topn);
warnings++;
}
/* adjust for topn == Infinity */
if (topn == Infinity)
{
/*
* For smart terminals, infinity really means everything that can
* be displayed, or Largest.
* On dumb terminals, infinity means every process in the system!
* We only really want to do that if it was explicitly specified.
* This is always the case when "Default_TOPN != Infinity". But if
* topn wasn't explicitly specified and we are on a dumb terminal
* and the default is Infinity, then (and only then) we use
* "Nominal_TOPN" instead.
*/
#if Default_TOPN == Infinity
topn = smart_terminal ? Largest :
(topn_specified ? Largest : Nominal_TOPN);
#else
topn = Largest;
#endif
}
/* set header display accordingly */
display_header(topn > 0);
/* determine interactive state */
if (interactive == Maybe)
{
interactive = smart_terminal;
}
/* if # of displays not specified, fill it in */
if (displays == 0)
{
displays = smart_terminal ? Infinity : 1;
}
/* hold interrupt signals while setting up the screen and the handlers */
#ifdef SIGHOLD
sighold(SIGINT);
sighold(SIGQUIT);
sighold(SIGTSTP);
#else
old_sigmask = sigblock(Smask(SIGINT) | Smask(SIGQUIT) | Smask(SIGTSTP));
#endif
init_screen();
(void) signal(SIGINT, leave);
(void) signal(SIGQUIT, leave);
(void) signal(SIGTSTP, tstop);
#ifdef SIGWINCH
(void) signal(SIGWINCH, winch);
#endif
#ifdef SIGRELSE
sigrelse(SIGINT);
sigrelse(SIGQUIT);
sigrelse(SIGTSTP);
#else
(void) sigsetmask(old_sigmask);
#endif
if (warnings)
{
fputs("....", stderr);
fflush(stderr); /* why must I do this? */
sleep((unsigned)(3 * warnings));
fputc('\n', stderr);
}
restart:
/*
* main loop -- repeat while display count is positive or while it
* indicates infinity (by being -1)
*/
while ((displays == -1) || (displays-- > 0))
{
/* get the current stats */
get_system_info(&system_info);
/* get the current set of processes */
processes =
get_process_info(&system_info,
&ps,
#ifdef ORDER
proc_compares[order_index]);
#else
proc_compare);
#endif
/* display the load averages */
(*d_loadave)(system_info.last_pid,
system_info.load_avg);
/* display the current time */
/* this method of getting the time SHOULD be fairly portable */
time(&curr_time);
i_uptime(&system_info.boottime, &curr_time);
i_timeofday(&curr_time);
/* display process state breakdown */
(*d_procstates)(system_info.p_total,
system_info.procstates);
/* display the cpu state percentage breakdown */
if (dostates) /* but not the first time */
{
(*d_cpustates)(system_info.cpustates);
}
else
{
/* we'll do it next time */
if (smart_terminal)
{
z_cpustates();
}
else
{
putchar('\n');
}
dostates = Yes;
}
/* display memory stats */
(*d_memory)(system_info.memory);
/* display swap stats */
(*d_swap)(system_info.swap);
/* handle message area */
(*d_message)();
/* update the header area */
(*d_header)(header_text);
if (topn > 0)
{
/* determine number of processes to actually display */
/* this number will be the smallest of: active processes,
number user requested, number current screen accomodates */
active_procs = system_info.p_active;
if (active_procs > topn)
{
active_procs = topn;
}
if (active_procs > max_topn)
{
active_procs = max_topn;
}
/* now show the top "n" processes. */
for (i = 0; i < active_procs; i++)
{
(*d_process)(i, format_next_process(processes, get_userid));
}
}
else
{
i = 0;
}
/* do end-screen processing */
u_endscreen(i);
/* now, flush the output buffer */
fflush(stdout);
/* only do the rest if we have more displays to show */
if (displays)
{
/* switch out for new display on smart terminals */
if (smart_terminal)
{
if (overstrike)
{
reset_display();
}
else
{
d_loadave = u_loadave;
d_procstates = u_procstates;
d_cpustates = u_cpustates;
d_memory = u_memory;
d_swap = u_swap;
d_message = u_message;
d_header = u_header;
d_process = u_process;
}
}
no_command = Yes;
if (!interactive)
{
/* set up alarm */
(void) signal(SIGALRM, onalrm);
(void) alarm((unsigned)delay);
/* wait for the rest of it .... */
pause();
}
else while (no_command)
{
/* assume valid command unless told otherwise */
no_command = No;
/* set up arguments for select with timeout */
FD_ZERO(&readfds);
FD_SET(1, &readfds); /* for standard input */
timeout.tv_sec = delay;
timeout.tv_usec = 0;
if (leaveflag) {
end_screen();
exit(0);
}
if (tstopflag) {
/* move to the lower left */
end_screen();
fflush(stdout);
/* default the signal handler action */
(void) signal(SIGTSTP, SIG_DFL);
/* unblock the signal and send ourselves one */
#ifdef SIGRELSE
sigrelse(SIGTSTP);
#else
(void) sigsetmask(sigblock(0) & ~(1 << (SIGTSTP - 1)));
#endif
(void) kill(0, SIGTSTP);
/* reset the signal handler */
(void) signal(SIGTSTP, tstop);
/* reinit screen */
reinit_screen();
reset_display();
tstopflag = 0;
goto restart;
}
if (winchflag) {
/* reascertain the screen dimensions */
get_screensize();
/* tell display to resize */
max_topn = display_resize();
/* reset the signal handler */
(void) signal(SIGWINCH, winch);
reset_display();
winchflag = 0;
goto restart;
}
/* wait for either input or the end of the delay period */
if (select(32, &readfds, (fd_set *)NULL, (fd_set *)NULL, &timeout) > 0)
{
int newval;
char *errmsg;
/* something to read -- clear the message area first */
clear_message();
/* now read it and convert to command strchr */
/* (use "change" as a temporary to hold strchr) */
(void) read(0, &ch, 1);
if ((iptr = strchr(command_chars, ch)) == NULL)
{
if (ch != '\r' && ch != '\n')
{
/* illegal command */
new_message(MT_standout, " Command not understood");
}
putchar('\r');
no_command = Yes;
}
else
{
change = iptr - command_chars;
if (overstrike && change > CMD_OSLIMIT)
{
/* error */
new_message(MT_standout,
" Command cannot be handled by this terminal");
putchar('\r');
no_command = Yes;
}
else switch(change)
{
case CMD_redraw: /* redraw screen */
reset_display();
break;
case CMD_update: /* merely update display */
/* is the load average high? */
if (system_info.load_avg[0] > LoadMax)
{
/* yes, go home for visual feedback */
go_home();
fflush(stdout);
}
break;
case CMD_quit: /* quit */
quit(0);
/*NOTREACHED*/
break;
case CMD_help1: /* help */
case CMD_help2:
reset_display();
clear();
show_help();
standout("Hit any key to continue: ");
fflush(stdout);
(void) read(0, &ch, 1);
break;
case CMD_errors: /* show errors */
if (error_count() == 0)
{
new_message(MT_standout,
" Currently no errors to report.");
putchar('\r');
no_command = Yes;
}
else
{
reset_display();
clear();
show_errors();
standout("Hit any key to continue: ");
fflush(stdout);
(void) read(0, &ch, 1);
}
break;
case CMD_number1: /* new number */
case CMD_number2:
new_message(MT_standout,
"Number of processes to show: ");
newval = readline(tempbuf1, 8, Yes);
if (newval > -1)
{
if (newval > max_topn)
{
new_message(MT_standout | MT_delayed,
" This terminal can only display %d processes.",
max_topn);
putchar('\r');
}
if (newval == 0)
{
/* inhibit the header */
display_header(No);
}
else if (newval > topn && topn == 0)
{
/* redraw the header */
display_header(Yes);
d_header = i_header;
}
topn = newval;
}
break;
case CMD_delay: /* new seconds delay */
new_message(MT_standout, "Seconds to delay: ");
if ((i = readline(tempbuf1, 8, Yes)) > -1)
{
delay = i;
}
clear_message();
break;
case CMD_displays: /* change display count */
new_message(MT_standout,
"Displays to show (currently %s): ",
displays == -1 ? "infinite" :
itoa(displays));
if ((i = readline(tempbuf1, 10, Yes)) > 0)
{
displays = i;
}
else if (i == 0)
{
quit(0);
}
clear_message();
break;
case CMD_kill: /* kill program */
new_message(0, "kill ");
if (readline(tempbuf2, sizeof(tempbuf2), No) > 0)
{
if ((errmsg = kill_procs(tempbuf2)) != NULL)
{
new_message(MT_standout, "%s", errmsg);
putchar('\r');
no_command = Yes;
}
}
else
{
clear_message();
}
break;
case CMD_renice: /* renice program */
new_message(0, "renice ");
if (readline(tempbuf2, sizeof(tempbuf2), No) > 0)
{
if ((errmsg = renice_procs(tempbuf2)) != NULL)
{
new_message(MT_standout, "%s", errmsg);
putchar('\r');
no_command = Yes;
}
}
else
{
clear_message();
}
break;
case CMD_idletog:
case CMD_idletog2:
ps.idle = !ps.idle;
new_message(MT_standout | MT_delayed,
" %sisplaying idle processes.",
ps.idle ? "D" : "Not d");
putchar('\r');
break;
case CMD_selftog:
ps.self = (ps.self == -1) ? getpid() : -1;
new_message(MT_standout | MT_delayed,
" %sisplaying self.",
(ps.self == -1) ? "D" : "Not d");
putchar('\r');
break;
case CMD_user:
new_message(MT_standout,
"Username to show: ");
if (readline(tempbuf2, sizeof(tempbuf2), No) > 0)
{
if (tempbuf2[0] == '+' &&
tempbuf2[1] == '\0')
{
ps.uid = -1;
}
else if ((i = userid(tempbuf2)) == -1)
{
new_message(MT_standout,
" %s: unknown user", tempbuf2);
no_command = Yes;
}
else
{
ps.uid = i;
}
putchar('\r');
}
else
{
clear_message();
}
break;
#ifdef ORDER
case CMD_order:
new_message(MT_standout,
"Order to sort: ");
if (readline(tempbuf2, sizeof(tempbuf2), No) > 0)
{
if ((i = string_index(tempbuf2, statics.order_names)) == -1)
{
new_message(MT_standout,
" %s: unrecognized sorting order", tempbuf2);
no_command = Yes;
}
else
{
order_index = i;
}
putchar('\r');
}
else
{
clear_message();
}
break;
#endif
default:
new_message(MT_standout, " BAD CASE IN SWITCH!");
putchar('\r');
}
}
/* flush out stuff that may have been written */
fflush(stdout);
}
}
}
}
quit(0);
/*NOTREACHED*/
}
/*
* reset_display() - reset all the display routine pointers so that entire
* screen will get redrawn.
*/
reset_display()
{
d_loadave = i_loadave;
d_procstates = i_procstates;
d_cpustates = i_cpustates;
d_memory = i_memory;
d_swap = i_swap;
d_message = i_message;
d_header = i_header;
d_process = i_process;
}
/*
* signal handlers
*/
sigret_t leave() /* exit under normal conditions -- INT handler */
{
leaveflag = 1;
}
sigret_t tstop(i) /* SIGTSTP handler */
int i;
{
tstopflag = 1;
}
#ifdef SIGWINCH
sigret_t winch(i) /* SIGWINCH handler */
int i;
{
winchflag = 1;
}
#endif
void quit(status) /* exit under duress */
int status;
{
end_screen();
exit(status);
/*NOTREACHED*/
}
sigret_t onalrm() /* SIGALRM handler */
{
/* this is only used in batch mode to break out of the pause() */
/* return; */
}