/*-
 *  Top users/processes display for Unix
 *
 *  This program may be freely redistributed,
 *  but this entire comment MUST remain intact.
 *
 *  Copyright (c) 1984, 1989, William LeFebvre, Rice University
 *  Copyright (c) 1989 - 1994, William LeFebvre, Northwestern University
 *  Copyright (c) 1994, 1995, William LeFebvre, Argonne National Laboratory
 *  Copyright (c) 1996, William LeFebvre, Group sys Consulting
 */

#include <sys/types.h>
#include <sys/time.h>
#include <sys/cdefs.h>
#include <sys/limits.h>
#include <sys/resource.h>
#include <sys/select.h>
#include <sys/signal.h>

#include <assert.h>
#include <err.h>
#include <errno.h>
#include <getopt.h>
#include <jail.h>
#include <locale.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <signal.h>
#include <string.h>
#include <unistd.h>

#include "commands.h"
#include "display.h"            /* interface to display package */
#include "screen.h"             /* interface to screen package */
#include "top.h"
#include "machine.h"
#include "utils.h"
#include "username.h"

/* Size of the stdio buffer given to stdout */
#define Buffersize      2048

char copyright[] =
    "Copyright (c) 1984 through 1996, William LeFebvre";

typedef void sigret_t;

/* The buffer that stdio will use */
static char stdoutbuf[Buffersize];

static int fmt_flags = 0;
int show_args = false;
int pcpu_stats = false;

/* signal handling routines */
static sigret_t leave(int);
static sigret_t tstop(int);
static sigret_t top_winch(int);

static volatile sig_atomic_t leaveflag;
static volatile sig_atomic_t tstopflag;
static volatile sig_atomic_t winchflag;

/* values which need to be accessed by signal handlers */
static int max_topn;            /* maximum displayable processes */

/* miscellaneous things */
struct process_select ps;
pid_t mypid;

/* pointers to display routines */
static void (*d_loadave)(int mpid, double *avenrun) = i_loadave;
static void (*d_procstates)(int total, int *brkdn) = i_procstates;
static void (*d_cpustates)(int *states) = i_cpustates;
static void (*d_memory)(int *stats) = i_memory;
static void (*d_arc)(int *stats) = i_arc;
static void (*d_carc)(int *stats) = i_carc;
static void (*d_swap)(int *stats) = i_swap;
static void (*d_message)(void) = i_message;
static void (*d_header)(const char *text) = i_header;
static void (*d_process)(int line, char *thisline) = i_process;

static void reset_display(void);

static const struct option longopts[] = {
    { "cpu-display-mode", no_argument, NULL, 'C' }, /* differs from orignal */
    /* D reserved */
    { "thread", no_argument, NULL, 'H' },
    { "idle-procs", no_argument, NULL, 'I' },
        { "jail", required_argument, NULL, 'J' },
        { "per-cpu", no_argument, NULL, 'P' },
    { "system-procs", no_argument, NULL, 'S' },
    { "thread-id", no_argument, NULL, 'T' }, /* differs from orignal */
    { "user", required_argument, NULL, 'U' },
    { "all", no_argument, NULL, 'a' },
    { "batch", no_argument, NULL, 'b' },
    /* c reserved */
    { "displays", required_argument, NULL, 'd' },
    { "interactive", no_argument, NULL, 'i' },
    { "jail-id", no_argument, NULL, 'j' },
    { "display-mode", required_argument, NULL, 'm' },
    /* n is identical to batch */
    { "sort-order", required_argument, NULL, 'o' },
    { "pid", required_argument, NULL, 'p' },
    { "quick", no_argument, NULL, 'q' },
    { "delay", required_argument, NULL, 's' },
    { "threads", no_argument, NULL, 't' },
    { "uids", no_argument, NULL, 'u' },
    { "version", no_argument, NULL, 'v' },
        { "swap", no_argument, NULL, 'w' },
        { "system-idle-procs", no_argument, NULL, 'z' },
        { NULL, 0, NULL, 0 }
};

static void
reset_uids(void)
{
    for (size_t i = 0; i < TOP_MAX_UIDS; ++i)
        ps.uid[i] = -1;
}

static int
add_uid(int uid)
{
    size_t i = 0;

    /* Add the uid if there's room */
    for (; i < TOP_MAX_UIDS; ++i)
    {
        if (ps.uid[i] == -1 || ps.uid[i] == uid)
        {
            ps.uid[i] = uid;
            break;
        }
    }

    return (i == TOP_MAX_UIDS);
}

static void
rem_uid(int uid)
{
    size_t i = 0;
    size_t where = TOP_MAX_UIDS;

    /* Look for the user to remove - no problem if it's not there */
    for (; i < TOP_MAX_UIDS; ++i)
    {
        if (ps.uid[i] == -1)
            break;
        if (ps.uid[i] == uid)
            where = i;
    }

    /* Make sure we don't leave a hole in the middle */
    if (where != TOP_MAX_UIDS)
    {
        ps.uid[where] = ps.uid[i-1];
        ps.uid[i-1] = -1;
    }
}

static int
handle_user(char *buf, size_t buflen)
{
    int rc = 0;
    int uid = -1;
    char *buf2 = buf;

    new_message(MT_standout, "Username to show (+ for all): ");
    if (readline(buf, buflen, false) <= 0)
    {
        clear_message();
        return (rc);
    }

    if (buf[0] == '+' || buf[0] == '-')
    {
        if (buf[1] == '\0')
        {
            reset_uids();
            goto end;
        }
        else
            ++buf2;
    }

    if ((uid = userid(buf2)) == -1)
    {
        new_message(MT_standout, " %s: unknown user", buf2);
        rc = 1;
        goto end;
    }

    if (buf2 == buf)
    {
        reset_uids();
        ps.uid[0] = uid;
        goto end;
    }

    if (buf[0] == '+')
    {
        if (add_uid(uid))
        {
            new_message(MT_standout, " too many users, reset with '+'");
            rc = 1;
            goto end;
        }
    }
    else
        rem_uid(uid);

end:
    putchar('\r');
    return (rc);
}

int
main(int argc, const char *argv[])
{
    int i;
    int active_procs;

    struct system_info system_info;
    struct statics statics;
    void * processes;

    static char tempbuf1[50];
    static char tempbuf2[50];
        sigset_t old_sigmask, new_sigmask;
    int topn = Infinity;
    struct timeval delay = { 2, 0 };
    int displays = 0;           /* indicates unspecified */
    int sel_ret = 0;
    time_t curr_time;
    char *(*get_userid)(int) = username;
    const char *uname_field = "USERNAME";
    const char *header_text;
    char *env_top;
    const char **preset_argv;
    int  preset_argc = 0;
    const char **av = NULL;
    int  ac = -1;
    bool do_unames = true;
    char interactive = 2;
    char warnings = 0;
    char topn_specified = false;
    char ch;
    char no_command = 1;
    struct timeval timeout;
    char *order_name = NULL;
    const struct sort_info *sort_info = NULL;
    fd_set readfds;
        char *nptr;

    /* set the buffer for stdout */
#ifdef DEBUG
    extern FILE *debug;
    debug = fopen("debug.run", "w");
    setbuffer(stdout, NULL, 0);
#else
    setbuffer(stdout, stdoutbuf, Buffersize);
#endif

    if (setlocale(LC_ALL, "") == NULL) {
        warnx("invalid locale, check your environment");
        sleep(2);
    }

    mypid = getpid();

    /* get our name */
    /* initialize some selection options */
    ps.idle    = true;
    ps.self    = true;
    ps.system  = false;
    reset_uids();
    ps.thread  = false;
    ps.wcpu    = 1;
    ps.jid     = -1;
    ps.jail    = false;
    ps.swap    = false;
    ps.kidle   = true;
    ps.pid     = -1;
    ps.command = NULL;
    ps.thread_id = false;

    /* 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_long(ac, __DECONST(char * const *, av), "CSIHPabijJ:nquvzs:d:U:m:o:p:Ttw", longopts, NULL)) != EOF)
        {
            switch(i)
            {
              case 'v':                 /* show version number */
                          errx(0, "version FreeBSD");
                          break;

              case 'u':                 /* toggle uid/username display */
                do_unames = !do_unames;
                break;

              case 'U':                 /* display only username's processes */
                if ((ps.uid[0] = userid(optarg)) == -1)
                {
                    errx(1, "%s: unknown user\n", optarg);
                }
                break;

              case 'S':                 /* show system processes */
                ps.system = true;
                break;

              case 'I':                   /* show idle processes */
                ps.idle = !ps.idle;
                break;

              case 'i':                 /* go interactive regardless */
                interactive = 1;
                break;

              case 'n':                 /* batch, or non-interactive */
              case 'b':
                interactive = 0;
                break;

              case 'a':
                fmt_flags ^= FMT_SHOWARGS;
                break;

              case 'd':                 /* number of displays to show */
                if ((i = atoiwi(optarg)) == Invalid || i == 0)
                {
                    warnx("warning: display count should be positive -- option ignored");
                    warnings++;
                }
                else
                {
                    displays = i;
                }
                break;
              case 'p': {
                unsigned long long num;
                const char *errstr;

                num = strtonum(optarg, 0, INT_MAX, &errstr);
                if (errstr != NULL || !find_pid(num)) {
                        fprintf(stderr, "%s: unknown pid\n", optarg);
                        exit(1);
                }
                ps.pid = (pid_t)num;
                ps.system = true;
                break;
              }

              case 's':
              {
                  double delay_d = strtod(optarg, &nptr);
                  if (nptr == optarg)
                  {
                      warnx("warning: invalid delay");
                      warnings++;
                  }
                  else if (delay_d <= 0)
                  {
                      warnx("warning: seconds delay should be positive -- using default");
                      warnings++;
                  }
                  else
                  {
                      delay.tv_sec = delay_d;
                      delay.tv_usec = (delay_d - delay.tv_sec) * 1e6;
                  }
                  break;
              }

              case 'q':         /* be quick about it */
                        errno = 0;
                        i = setpriority(PRIO_PROCESS, 0, PRIO_MIN);
                        if (i == -1 && errno != 0) {
                                warnx("warning: `-q' option failed (%m)");
                                warnings++;
                        }
                break;

              case 'm':         /* select display mode */
                if (strcmp(optarg, "io") == 0) {
                        displaymode = DISP_IO;
                } else if (strcmp(optarg, "cpu") == 0) {
                        displaymode = DISP_CPU;
                } else {
                        errx(1, "warning: `-m' option can only take args 'io' or 'cpu'");
                }
                break;

              case 'o':         /* select sort order */
                order_name = optarg;
                break;

              case 't':
                ps.self = !ps.self;
                break;

              case 'C':
                ps.wcpu = !ps.wcpu;
                break;

              case 'H':
                ps.thread = !ps.thread;
                break;

              case 'T':
                ps.thread_id = !ps.thread_id;
                break;

              case 'j':
                ps.jail = !ps.jail;
                break;

              case 'J':                 /* display only jail's processes */
                if ((ps.jid = jail_getid(optarg)) == -1)
                {
                    fprintf(stderr, "%s: unknown jail\n", optarg);
                    exit(1);
                }
                ps.jail = 1;
                break;

              case 'P':
                pcpu_stats = !pcpu_stats;
                break;

              case 'w':
                ps.swap = 1;
                break;

              case 'z':
                ps.kidle = !ps.kidle;
                break;

              default:
                errx(1, 
"[-abCHIijnPqSTtuvwz] [-d count] [-J jail] [-m cpu | io] [-o field]\n"
"     [-p pid] [-s time] [-U username] [number]");
            }
        }

        /* get count of top processes to display (if any) */
        if (optind < ac)
        {
            if ((topn = atoiwi(av[optind])) == Invalid)
            {
                        warnx("warning: process display count should be non-negative -- using default");
                        warnings++;
            }
            else
            {
                topn_specified = true;
            }
        }

        /* 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);
    }

    /* determine sorting order index, if necessary */
    if (order_name != NULL)
    {
        if ((sort_info = get_sort_info(order_name)) == NULL) {
            warnx("'%s' is not a recognized sorting order.", order_name);
            fprintf(stderr, "\tTry one of these:");
            dump_sort_names(stderr);
            fputc('\n', stderr);
            exit(1);
        }
    }
    else
    {
        sort_info = get_sort_info(NULL);
    }

    /* 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)
    {
                errx(4, "can't allocate sufficient memory");
    }

    /* print warning if user requested more processes than we can display */
    if (topn > max_topn)
    {
                warnx("warning: this terminal can only display %d processes.", 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.
         */
        topn = smart_terminal ? Largest :
                    (topn_specified ? Largest : Nominal_TOPN);
    }

    /* set header display accordingly */
    display_header(topn > 0);

    /* determine interactive state */
    if (interactive == 2)
    {
        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 */

        sigemptyset(&new_sigmask);
        sigaddset(&new_sigmask, SIGINT);
        sigaddset(&new_sigmask, SIGQUIT);
        sigaddset(&new_sigmask, SIGTSTP);
        sigprocmask(SIG_BLOCK, &new_sigmask, &old_sigmask);
    init_screen();
    signal(SIGINT, leave);
    signal(SIGQUIT, leave);
    signal(SIGTSTP, tstop);
    signal(SIGWINCH, top_winch);
    sigprocmask(SIG_SETMASK, &old_sigmask, NULL);
    if (warnings)
    {
        fputs("....", stderr);
        fflush(stderr);
        sleep(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, sort_info);

        /* display the load averages */
        (*d_loadave)(system_info.last_pid,
                     system_info.load_avg);

        /* display the battery info (if any) */
        i_battery(statics.nbatteries, system_info.battery);

        /* 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);
        (*d_cpustates)(system_info.cpustates);

        /* display memory stats */
        (*d_memory)(system_info.memory);
        (*d_arc)(system_info.arc);
        (*d_carc)(system_info.carc);

        /* 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 accommodates */
            active_procs = system_info.p_pactive;
            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,
                             fmt_flags));
            }
        }
        else
        {
            i = 0;
        }

        /* do end-screen processing */
        u_endscreen(i);

        /* now, flush the output buffer */
        if (fflush(stdout) != 0)
        {
            new_message(MT_standout, " Write error on stdout");
            putchar('\r');
            quit(1);
        }

        /* 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_arc = u_arc;
                    d_carc = u_carc;
                    d_swap = u_swap;
                    d_message = u_message;
                    d_header = u_header;
                    d_process = u_process;
                }
            }

            no_command = true;
            if (!interactive)
            {
                timeout = delay;
                select(0, NULL, NULL, NULL, &timeout);
                if (leaveflag) {
                    end_screen();
                    exit(0);
                }
            }
            else while (no_command)
            {
                /* assume valid command unless told otherwise */
                no_command = false;

                /* set up arguments for select with timeout */
                FD_ZERO(&readfds);
                FD_SET(0, &readfds);            /* for standard input */
                timeout = delay;

                if (leaveflag) {
                    end_screen();
                    exit(0);
                }

                if (tstopflag) {
                    /* move to the lower left */
                    end_screen();
                    fflush(stdout);

                    /* default the signal handler action */
                    signal(SIGTSTP, SIG_DFL);

                    /* unblock the signal and send ourselves one */
                    sigsetmask(sigblock(0) & ~(1 << (SIGTSTP - 1)));
                    kill(0, SIGTSTP);

                    /* reset the signal handler */
                    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 */
                    signal(SIGWINCH, top_winch);

                    reset_display();
                    winchflag = 0;
                    goto restart;
                }

                /* wait for either input or the end of the delay period */
                sel_ret = select(2, &readfds, NULL, NULL, &timeout);
                if (sel_ret < 0 && errno != EINTR)
                    quit(0);
                if (sel_ret > 0)
                {
                    int newval;
                    const char *errmsg;
                        const struct command *cptr;

                    /* 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) */
                    if (read(0, &ch, 1) != 1)
                    {
                        /* read error: either 0 or -1 */
                        new_message(MT_standout, " Read error on stdin");
                        putchar('\r');
                        quit(1);
                    }
                        if (ch == '\r' || ch == '\n') {
                                continue;
                        }
                        cptr = all_commands;
                        while (cptr->c != '\0') {
                                if (cptr->c == ch) {
                                        break;
                                }
                                cptr++;
                        }
                        if (cptr->c == '\0') {
                            new_message(MT_standout, " Command not understood");
                            putchar('\r');
                                no_command = true;
                        }
                        if (overstrike && !cptr->available_to_dumb)
                        {
                            new_message(MT_standout,
                            " Command cannot be handled by this terminal");
                            putchar('\r');
                                no_command = true;
                        }
                        if (!no_command) {
                        switch(cptr->id)
                        {
                            case CMD_redraw:    /* redraw screen */
                                reset_display();
                                break;

                            case CMD_update:    /* merely update display */
                                break;

                            case CMD_quit:
                                quit(0);
                                break;

                            case CMD_help:
                                reset_display();
                                top_clear();
                                show_help();
                                top_standout("Hit any key to continue: ");
                                fflush(stdout);
                                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 = true;
                                }
                                else
                                {
                                    reset_display();
                                    top_clear();
                                    show_errors();
                                    top_standout("Hit any key to continue: ");
                                    fflush(stdout);
                                    read(0, &ch, 1);
                                }
                                break;

                            case CMD_number:
                                new_message(MT_standout,
                                    "Number of processes to show: ");
                                newval = readline(tempbuf1, 8, true);
                                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(false);
                                    }
                                    else if (newval > topn && topn == 0)
                                    {
                                        /* redraw the header */
                                        display_header(true);
                                        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, false)) > 0)
                                {
                                    double delay_d = strtod(tempbuf1, &nptr);
                                    if (nptr == tempbuf1 || delay_d <= 0)
                                    {
                                        new_message(MT_standout, " Invalid delay");
                                        putchar('\r');
                                        no_command = true;
                                    }
                                    else
                                    {
                                        delay.tv_sec = delay_d;
                                        delay.tv_usec = (delay_d - delay.tv_sec) * 1e6;
                                        clear_message();
                                    }
                                }
                                break;

                            case CMD_grep: /* grep command name */
                                new_message(MT_standout,
                                    "Grep command name (+ for all): ");
                                if (readline(tempbuf1, sizeof(tempbuf1), false) > 0) {
                                        free(ps.command);
                                        if (tempbuf1[0] == '+' && tempbuf1[1] == '\0') {
                                                ps.command = NULL;
                                        } else if ((ps.command = strdup(tempbuf1)) == NULL)
                                                quit(1);
                                }
                                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, true)) > 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), false) > 0)
                                {
                                    if ((errmsg = kill_procs(tempbuf2)) != NULL)
                                    {
                                        new_message(MT_standout, "%s", errmsg);
                                        putchar('\r');
                                        no_command = true;
                                    }
                                }
                                else
                                {
                                    clear_message();
                                }
                                break;

                            case CMD_renice:    /* renice program */
                                new_message(0, "renice ");
                                if (readline(tempbuf2, sizeof(tempbuf2), false) > 0)
                                {
                                    if ((errmsg = renice_procs(tempbuf2)) != NULL)
                                    {
                                        new_message(MT_standout, "%s", errmsg);
                                        putchar('\r');
                                        no_command = true;
                                    }
                                }
                                else
                                {
                                    clear_message();
                                }
                                break;

                            case CMD_idletog:
                                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;
                                new_message(MT_standout | MT_delayed,
                                    " %sisplaying self.",
                                    (ps.self) ? "D" : "Not d");
                                putchar('\r');
                                break;

                            case CMD_user:
                                if (handle_user(tempbuf2, sizeof(tempbuf2)))
                                    no_command = true;
                                break;

                            case CMD_thrtog:
                                ps.thread = !ps.thread;
                                new_message(MT_standout | MT_delayed,
                                    " Displaying threads %s",
                                    ps.thread ? "separately" : "as a count");
                                header_text = format_header(uname_field);
                                reset_display();
                                putchar('\r');
                                break;

                            case CMD_toggletid:
                                ps.thread_id = !ps.thread_id;
                                new_message(MT_standout | MT_delayed,
                                    " Displaying %s",
                                    ps.thread_id ? "tid" : "pid");
                                header_text = format_header(uname_field);
                                reset_display();
                                putchar('\r');
                                break;

                            case CMD_wcputog:
                                ps.wcpu = !ps.wcpu;
                                new_message(MT_standout | MT_delayed,
                                    " Displaying %s CPU",
                                    ps.wcpu ? "weighted" : "raw");
                                header_text = format_header(uname_field);
                                reset_display();
                                putchar('\r');
                                break;
                            case CMD_viewtog:
                                displaymode = displaymode == DISP_IO ? DISP_CPU : DISP_IO;
                                new_message(MT_standout | MT_delayed,
                                    " Displaying %s statistics.",
                                    displaymode == DISP_IO ? "IO" : "CPU");
                                header_text = format_header(uname_field);
                                display_header(true);
                                d_header = i_header;
                                reset_display();
                                break;
                            case CMD_viewsys:
                                ps.system = !ps.system;
                                new_message(MT_standout | MT_delayed,
                                    " %sisplaying system processes.",
                                    ps.system ? "D" : "Not d");
                                break;
                            case CMD_showargs:
                                fmt_flags ^= FMT_SHOWARGS;
                                show_args = fmt_flags & FMT_SHOWARGS;
                                new_message(MT_standout | MT_delayed,
                                    " %sisplaying process arguments.",
                                    fmt_flags & FMT_SHOWARGS ? "D" : "Not d");
                                break;
                            case CMD_order:
                                new_message(MT_standout,
                                    "Order to sort: ");
                                if (readline(tempbuf2, sizeof(tempbuf2), false) > 0)
                                {
                                  const struct sort_info *new_sort_info;

                                  if ((new_sort_info = get_sort_info(tempbuf2)) == NULL)
                                        {
                                          new_message(MT_standout,
                                              " %s: unrecognized sorting order", tempbuf2);
                                          no_command = true;
                                    }
                                    else
                                    {
                                        sort_info = new_sort_info;
                                    }
                                    putchar('\r');
                                }
                                else
                                {
                                    clear_message();
                                }
                                break;
                            case CMD_jidtog:
                                ps.jail = !ps.jail;
                                new_message(MT_standout | MT_delayed,
                                    " %sisplaying jail ID.",
                                    ps.jail ? "D" : "Not d");
                                header_text = format_header(uname_field);
                                reset_display();
                                putchar('\r');
                                break;

                            case CMD_jail:
                                new_message(MT_standout,
                                    "Jail to show (+ for all): ");
                                if (readline(tempbuf2, sizeof(tempbuf2), false) > 0)
                                {
                                    if (tempbuf2[0] == '+' &&
                                        tempbuf2[1] == '\0')
                                    {
                                        ps.jid = -1;
                                    }
                                    else if ((i = jail_getid(tempbuf2)) == -1)
                                    {
                                        new_message(MT_standout,
                                            " %s: unknown jail", tempbuf2);
                                        no_command = true;
                                    }
                                    else
                                    {
                                        ps.jid = i;
                                    }
                                    if (ps.jail == 0) {
                                            ps.jail = 1;
                                            new_message(MT_standout |
                                                MT_delayed, " Displaying jail "
                                                "ID.");
                                            header_text =
                                                format_header(uname_field);
                                            reset_display();
                                    }
                                    putchar('\r');
                                }
                                else
                                {
                                    clear_message();
                                }
                                break;

                            case CMD_kidletog:
                                ps.kidle = !ps.kidle;
                                new_message(MT_standout | MT_delayed,
                                    " %sisplaying system idle process.",
                                    ps.kidle ? "D" : "Not d");
                                putchar('\r');
                                break;
                            case CMD_pcputog:
                                pcpu_stats = !pcpu_stats;
                                new_message(MT_standout | MT_delayed,
                                    " Displaying %sCPU statistics.",
                                    pcpu_stats ? "per-" : "global ");
                                toggle_pcpustats();
                                max_topn = display_updatecpus(&statics);
                                reset_display();
                                putchar('\r');
                                break;
                            case CMD_swaptog:
                                ps.swap = !ps.swap;
                                new_message(MT_standout | MT_delayed,
                                    " %sisplaying per-process swap usage.",
                                    ps.swap ? "D" : "Not d");
                                header_text = format_header(uname_field);
                                reset_display();
                                putchar('\r');
                                break;
                            case CMD_pid:
                                new_message(MT_standout,
                                        "Process id to show (+ for all): ");
                                if (readline(tempbuf2, sizeof(tempbuf2), false) > 0) {
                                        if (tempbuf2[0] == '+' &&
                                            tempbuf2[1] == '\0') {
                                                ps.pid = (pid_t)-1;
                                        } else {
                                                unsigned long long num;
                                                const char *errstr;

                                                num = strtonum(tempbuf2, 0, INT_MAX,
                                                        &errstr);
                                                if (errstr != NULL || !find_pid(num)) {
                                                        new_message(MT_standout,
                                                                " %s: unknown pid",
                                                                tempbuf2);
                                                        no_command = true;
                                                } else {
                                                        ps.pid = (pid_t)num;
                                                }
                                        }
                                        putchar('\r');
                                } else
                                        clear_message();
                                break;
                            case CMD_NONE:
                                        assert(false && "reached switch without command");
                        }
                        }
                    }

                    /* flush out stuff that may have been written */
                    fflush(stdout);
                }
            }
    }

#ifdef DEBUG
    fclose(debug);
#endif
    quit(0);
}

/*
 *  reset_display() - reset all the display routine pointers so that entire
 *      screen will get redrawn.
 */

static void
reset_display(void)
{
    d_loadave    = i_loadave;
    d_procstates = i_procstates;
    d_cpustates  = i_cpustates;
    d_memory     = i_memory;
    d_arc        = i_arc;
    d_carc       = i_carc;
    d_swap       = i_swap;
    d_message    = i_message;
    d_header     = i_header;
    d_process    = i_process;
}

/*
 *  signal handlers
 */

static sigret_t
leave(int i __unused)   /* exit under normal conditions -- INT handler */
{

    leaveflag = 1;
}

static sigret_t
tstop(int i __unused)   /* SIGTSTP handler */
{

    tstopflag = 1;
}

static sigret_t
top_winch(int i __unused)               /* SIGWINCH handler */
{

    winchflag = 1;
}

void __dead2
quit(int status)                /* exit under duress */
{
    end_screen();
    exit(status);
}