/* $OpenBSD: machine.c,v 1.113 2023/01/07 05:24:59 guenther Exp $        */

/*-
 * Copyright (c) 1994 Thorsten Lockert <tholo@sigmasoft.com>
 * 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.
 * 3. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED ``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 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.
 *
 * AUTHOR:  Thorsten Lockert <tholo@sigmasoft.com>
 *          Adapted from BSD4.4 by Christos Zoulas <christos@ee.cornell.edu>
 *          Patch for process wait display by Jarl F. Greipsland <jarle@idt.unit.no>
 *          Patch for -DORDER by Kenneth Stailey <kstailey@disclosure.com>
 *          Patch for new swapctl(2) by Tobias Weingartner <weingart@openbsd.org>
 */

#include <sys/param.h>  /* DEV_BSIZE PZERO */
#include <sys/types.h>
#include <sys/signal.h>
#include <sys/mount.h>
#include <sys/proc.h>
#include <sys/sched.h>
#include <sys/swap.h>
#include <sys/sysctl.h>

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <err.h>
#include <errno.h>

#include "top.h"
#include "display.h"
#include "machine.h"
#include "utils.h"

static int      swapmode(int *, int *);
static char     *state_abbr(struct kinfo_proc *);
static char     *format_comm(struct kinfo_proc *);
static int      cmd_matches(struct kinfo_proc *, char *);
static char     **get_proc_args(struct kinfo_proc *);

/* get_process_info passes back a handle.  This is what it looks like: */

struct handle {
        struct kinfo_proc **next_proc;  /* points to next valid proc pointer */
};

/* what we consider to be process size: */
#define PROCSIZE(pp) ((pp)->p_vm_tsize + (pp)->p_vm_dsize + (pp)->p_vm_ssize)

/*
 *  These definitions control the format of the per-process area
 */
static char header[] =
        "  PID X        PRI NICE  SIZE   RES STATE     WAIT      TIME    CPU COMMAND";

/* offsets in the header line to start alternative columns */
#define UNAME_START 6
#define RTABLE_START 46

#define Proc_format \
        "%5d %-8.8s %3d %4d %5s %5s %-9s %-7.7s %6s %5.2f%% %s"

/* process state names for the "STATE" column of the display */
char    *state_abbrev[] = {
        "", "start", "run", "sleep", "stop", "zomb", "dead", "onproc"
};

/* these are for calculating cpu state percentages */
static struct cpustats  *cp_time;
static struct cpustats  *cp_old;
static struct cpustats  *cp_diff;

/* these are for detailing the process states */
int process_states[8];
char *procstatenames[] = {
        "", " starting, ", " running, ", " idle, ",
        " stopped, ", " zombie, ", " dead, ", " on processor, ",
        NULL
};

/* these are for detailing the cpu states */
int64_t *cpu_states;
char *cpustatenames[] = {
        "user", "nice", "sys", "spin", "intr", "idle", NULL
};

/* this is for tracking which cpus are online */
int *cpu_online;

/* these are for detailing the memory statistics */
int memory_stats[10];
char *memorynames[] = {
        "Real: ", "K/", "K act/tot ", "Free: ", "K ",
        "Cache: ", "K ",
        "Swap: ", "K/", "K",
        NULL
};

/* these are names given to allowed sorting orders -- first is default */
char    *ordernames[] = {
        "cpu", "size", "res", "time", "pri", "pid", "command", NULL
};

/* these are for keeping track of the proc array */
static int      nproc;
static int      onproc = -1;
static int      pref_len;
static struct kinfo_proc *pbase;
static struct kinfo_proc **pref;

/* these are for getting the memory statistics */
static int      pageshift;      /* log base 2 of the pagesize */

/* define pagetok in terms of pageshift */
#define pagetok(size) ((size) << pageshift)

int             ncpu;
int             ncpuonline;
int             fscale;

unsigned int    maxslp;

int
getfscale(void)
{
        int mib[] = { CTL_KERN, KERN_FSCALE };
        size_t size = sizeof(fscale);

        if (sysctl(mib, sizeof(mib) / sizeof(mib[0]),
            &fscale, &size, NULL, 0) == -1)
                return (-1);
        return fscale;
}

int
getncpu(void)
{
        int mib[] = { CTL_HW, HW_NCPU };
        int numcpu;
        size_t size = sizeof(numcpu);

        if (sysctl(mib, sizeof(mib) / sizeof(mib[0]),
            &numcpu, &size, NULL, 0) == -1)
                return (-1);

        return (numcpu);
}

int
getncpuonline(void)
{
        int mib[] = { CTL_HW, HW_NCPUONLINE };
        int numcpu;
        size_t size = sizeof(numcpu);

        if (sysctl(mib, sizeof(mib) / sizeof(mib[0]),
            &numcpu, &size, NULL, 0) == -1)
                return (-1);

        return (numcpu);
}

int
machine_init(struct statics *statics)
{
        int pagesize;

        ncpu = getncpu();
        if (ncpu == -1)
                return (-1);
        if (getfscale() == -1)
                return (-1);
        cpu_states = calloc(ncpu, CPUSTATES * sizeof(int64_t));
        if (cpu_states == NULL)
                err(1, NULL);
        cp_time = calloc(ncpu, sizeof(*cp_time));
        cp_old  = calloc(ncpu, sizeof(*cp_old));
        cp_diff = calloc(ncpu, sizeof(*cp_diff));
        if (cp_time == NULL || cp_old == NULL || cp_diff == NULL)
                err(1, NULL);
        cpu_online = calloc(ncpu, sizeof(*cpu_online));
        if (cpu_online == NULL)
                err(1, NULL);

        /*
         * get the page size with "getpagesize" and calculate pageshift from
         * it
         */
        pagesize = getpagesize();
        pageshift = 0;
        while (pagesize > 1) {
                pageshift++;
                pagesize >>= 1;
        }

        /* we only need the amount of log(2)1024 for our conversion */
        pageshift -= LOG1024;

        /* fill in the statics information */
        statics->procstate_names = procstatenames;
        statics->cpustate_names = cpustatenames;
        statics->memory_names = memorynames;
        statics->order_names = ordernames;
        return (0);
}

char *
format_header(char *second_field, char *eighth_field)
{
        char *second_fieldp = second_field, *eighth_fieldp = eighth_field, *ptr;

        ptr = header + UNAME_START;
        while (*second_fieldp != '\0')
                *ptr++ = *second_fieldp++;
        ptr = header + RTABLE_START;
        while (*eighth_fieldp != '\0')
                *ptr++ = *eighth_fieldp++;
        return (header);
}

void
get_system_info(struct system_info *si)
{
        static int cpustats_mib[] = {CTL_KERN, KERN_CPUSTATS, /*fillme*/0};
        static int sysload_mib[] = {CTL_VM, VM_LOADAVG};
        static int uvmexp_mib[] = {CTL_VM, VM_UVMEXP};
        static int bcstats_mib[] = {CTL_VFS, VFS_GENERIC, VFS_BCACHESTAT};
        struct loadavg sysload;
        struct uvmexp uvmexp;
        struct bcachestats bcstats;
        double *infoloadp;
        size_t size;
        int i;
        int64_t *tmpstate;

        size = sizeof(*cp_time);
        for (i = 0; i < ncpu; i++) {
                cpustats_mib[2] = i;
                tmpstate = cpu_states + (CPUSTATES * i);
                if (sysctl(cpustats_mib, 3, &cp_time[i], &size, NULL, 0) == -1)
                        warn("sysctl kern.cpustats failed");
                /* convert cpustats counts to percentages */
                (void) percentages(CPUSTATES, tmpstate, cp_time[i].cs_time,
                    cp_old[i].cs_time, cp_diff[i].cs_time);
                /* note whether the cpu is online */
                cpu_online[i] = (cp_time[i].cs_flags & CPUSTATS_ONLINE) != 0;
        }

        size = sizeof(sysload);
        if (sysctl(sysload_mib, 2, &sysload, &size, NULL, 0) == -1)
                warn("sysctl failed");
        infoloadp = si->load_avg;
        for (i = 0; i < 3; i++)
                *infoloadp++ = ((double) sysload.ldavg[i]) / sysload.fscale;


        /* get total -- systemwide main memory usage structure */
        size = sizeof(uvmexp);
        if (sysctl(uvmexp_mib, 2, &uvmexp, &size, NULL, 0) == -1) {
                warn("sysctl failed");
                bzero(&uvmexp, sizeof(uvmexp));
        }
        size = sizeof(bcstats);
        if (sysctl(bcstats_mib, 3, &bcstats, &size, NULL, 0) == -1) {
                warn("sysctl failed");
                bzero(&bcstats, sizeof(bcstats));
        }
        /* convert memory stats to Kbytes */
        memory_stats[0] = -1;
        memory_stats[1] = pagetok(uvmexp.active);
        memory_stats[2] = pagetok(uvmexp.npages - uvmexp.free);
        memory_stats[3] = -1;
        memory_stats[4] = pagetok(uvmexp.free);
        memory_stats[5] = -1;
        memory_stats[6] = pagetok(bcstats.numbufpages);
        memory_stats[7] = -1;

        if (!swapmode(&memory_stats[8], &memory_stats[9])) {
                memory_stats[8] = 0;
                memory_stats[9] = 0;
        }

        /* set arrays and strings */
        si->cpustates = cpu_states;
        si->cpuonline = cpu_online;
        si->memory = memory_stats;
}

static struct handle handle;

struct kinfo_proc *
getprocs(int op, int arg, int *cnt)
{
        size_t size;
        int mib[6] = {CTL_KERN, KERN_PROC, KERN_PROC_ALL, 0,
            sizeof(struct kinfo_proc), 0};
        static int maxslp_mib[] = {CTL_VM, VM_MAXSLP};
        static struct kinfo_proc *procbase;
        int st;

        mib[2] = op;
        mib[3] = arg;

        size = sizeof(maxslp);
        if (sysctl(maxslp_mib, 2, &maxslp, &size, NULL, 0) == -1) {
                warn("sysctl vm.maxslp failed");
                return (0);
        }
    retry:
        free(procbase);
        st = sysctl(mib, 6, NULL, &size, NULL, 0);
        if (st == -1) {
                /* _kvm_syserr(kd, kd->program, "kvm_getprocs"); */
                return (0);
        }
        size = 5 * size / 4;                    /* extra slop */
        if ((procbase = malloc(size)) == NULL)
                return (0);
        mib[5] = (int)(size / sizeof(struct kinfo_proc));
        st = sysctl(mib, 6, procbase, &size, NULL, 0);
        if (st == -1) {
                if (errno == ENOMEM)
                        goto retry;
                /* _kvm_syserr(kd, kd->program, "kvm_getprocs"); */
                return (0);
        }
        *cnt = (int)(size / sizeof(struct kinfo_proc));
        return (procbase);
}

static char **
get_proc_args(struct kinfo_proc *kp)
{
        static char     **s;
        static size_t   siz = 1023;
        int             mib[4];

        if (!s && !(s = malloc(siz)))
                err(1, NULL);

        mib[0] = CTL_KERN;
        mib[1] = KERN_PROC_ARGS;
        mib[2] = kp->p_pid;
        mib[3] = KERN_PROC_ARGV;
        for (;;) {
                size_t space = siz;
                if (sysctl(mib, 4, s, &space, NULL, 0) == 0)
                        break;
                if (errno != ENOMEM)
                        return NULL;
                siz *= 2;
                if ((s = realloc(s, siz)) == NULL)
                        err(1, NULL);
        }
        return s;
}

static int
cmd_matches(struct kinfo_proc *proc, char *term)
{
        extern int      show_args;
        char            **args = NULL;

        if (!term) {
                /* No command filter set */
                return 1;
        } else {
                /* Filter set, process name needs to contain term */
                if (strstr(proc->p_comm, term))
                        return 1;
                /* If thread name set, search that too */
                if (strstr(proc->p_name, term))
                        return 1;
                /* If showing arguments, search those as well */
                if (show_args) {
                        args = get_proc_args(proc);

                        if (args == NULL) {
                                /* Failed to get args, so can't search them */
                                return 0;
                        }

                        while (*args != NULL) {
                                if (strstr(*args, term))
                                        return 1;
                                args++;
                        }
                }
        }
        return 0;
}

struct handle *
get_process_info(struct system_info *si, struct process_select *sel,
    int (*compare) (const void *, const void *))
{
        int show_idle, show_system, show_threads, show_uid, show_pid, show_cmd;
        int show_rtableid, hide_rtableid, hide_uid;
        int total_procs, active_procs;
        struct kinfo_proc **prefp, *pp;
        int what = KERN_PROC_ALL;

        show_system = sel->system;
        show_threads = sel->threads;

        if (show_system)
                what = KERN_PROC_KTHREAD;
        if (show_threads)
                what |= KERN_PROC_SHOW_THREADS;

        if ((pbase = getprocs(what, 0, &nproc)) == NULL) {
                /* warnx("%s", kvm_geterr(kd)); */
                quit(23);
        }
        if (nproc > onproc)
                pref = reallocarray(pref, (onproc = nproc),
                    sizeof(struct kinfo_proc *));
        if (pref == NULL) {
                warnx("Out of memory.");
                quit(23);
        }
        /* get a pointer to the states summary array */
        si->procstates = process_states;

        /* set up flags which define what we are going to select */
        show_idle = sel->idle;
        show_uid = sel->uid != (uid_t)-1;
        hide_uid = sel->huid != (uid_t)-1;
        show_pid = sel->pid != (pid_t)-1;
        show_rtableid = sel->rtableid != -1;
        hide_rtableid = sel->hrtableid != -1;
        show_cmd = sel->command != NULL;

        /* count up process states and get pointers to interesting procs */
        total_procs = 0;
        active_procs = 0;
        memset((char *) process_states, 0, sizeof(process_states));
        prefp = pref;
        for (pp = pbase; pp < &pbase[nproc]; pp++) {
                /*
                 * When showing threads, we want to ignore the structure
                 * that represents the entire process, which has TID == -1
                 */
                if (show_threads && pp->p_tid == -1)
                        continue;
                /*
                 * Place pointers to each valid proc structure in pref[].
                 * Process slots that are actually in use have a non-zero
                 * status field.
                 */
                if (pp->p_stat != 0) {
                        total_procs++;
                        process_states[(unsigned char) pp->p_stat]++;
                        if ((pp->p_psflags & PS_ZOMBIE) == 0 &&
                            (show_idle || pp->p_pctcpu != 0 ||
                            pp->p_stat == SRUN) &&
                            (!hide_uid || pp->p_ruid != sel->huid) &&
                            (!show_uid || pp->p_ruid == sel->uid) &&
                            (!show_pid || pp->p_pid == sel->pid) &&
                            (!hide_rtableid || pp->p_rtableid != sel->hrtableid) &&
                            (!show_rtableid || pp->p_rtableid == sel->rtableid) &&
                            (!show_cmd || cmd_matches(pp, sel->command))) {
                                *prefp++ = pp;
                                active_procs++;
                        }
                }
        }

        qsort((char *)pref, active_procs, sizeof(struct kinfo_proc *), compare);
        /* remember active and total counts */
        si->p_total = total_procs;
        si->p_active = pref_len = active_procs;

        /* pass back a handle */
        handle.next_proc = pref;
        return &handle;
}

char fmt[MAX_COLS];     /* static area where result is built */

static char *
state_abbr(struct kinfo_proc *pp)
{
        static char buf[10];

        if (ncpu > 1 && pp->p_cpuid != KI_NOCPU)
                snprintf(buf, sizeof buf, "%s/%llu",
                    state_abbrev[(unsigned char)pp->p_stat], pp->p_cpuid);
        else
                snprintf(buf, sizeof buf, "%s",
                    state_abbrev[(unsigned char)pp->p_stat]);
        return buf;
}

static char *
format_comm(struct kinfo_proc *kp)
{
        static char     buf[MAX_COLS];
        char            **p, **s;
        extern int      show_args;

        if (show_args && (s = get_proc_args(kp)) != NULL) {
                buf[0] = '\0';
                for (p = s; *p != NULL; p++) {
                        if (p != s)
                                strlcat(buf, " ", sizeof(buf));
                        strlcat(buf, *p, sizeof(buf));
                }
                if (buf[0] != '\0')
                        return buf;
        }
        if (kp->p_name[0] != '\0') {
                snprintf(buf, sizeof buf, "%s/%s", kp->p_comm,
                    kp->p_name);
                return buf;
        }
        return kp->p_comm;
}

void
skip_processes(struct handle *hndl, int n)
{
        hndl->next_proc += n;
}

char *
format_next_process(struct handle *hndl, const char *(*get_userid)(uid_t, int),
    int rtable, pid_t *pid)
{
        struct kinfo_proc *pp;
        int cputime;
        double pct;
        char second_buf[16], eighth_buf[8];

        /* find and remember the next proc structure */
        pp = *(hndl->next_proc++);

        cputime = pp->p_rtime_sec + ((pp->p_rtime_usec + 500000) / 1000000);

        /* calculate the base for cpu percentages */
        pct = (double)pp->p_pctcpu / fscale;

        if (get_userid == NULL)
                snprintf(second_buf, sizeof(second_buf), "%8d", pp->p_tid);
        else
                strlcpy(second_buf, (*get_userid)(pp->p_ruid, 0),
                    sizeof(second_buf));

        if (rtable)
                snprintf(eighth_buf, sizeof(eighth_buf), "%7d", pp->p_rtableid);
        else
                strlcpy(eighth_buf, pp->p_wmesg[0] ? pp->p_wmesg : "-",
                    sizeof(eighth_buf));

        /* format this entry */
        snprintf(fmt, sizeof(fmt), Proc_format, pp->p_pid, second_buf,
            pp->p_priority - PZERO, pp->p_nice - NZERO,
            format_k(pagetok(PROCSIZE(pp))),
            format_k(pagetok(pp->p_vm_rssize)),
            (pp->p_stat == SSLEEP && pp->p_slptime > maxslp) ?
            "idle" : state_abbr(pp),
            eighth_buf, format_time(cputime), 100.0 * pct,
            printable(format_comm(pp)));

        *pid = pp->p_pid;
        /* return the result */
        return (fmt);
}

/* comparison routine for qsort */
static unsigned char sorted_state[] =
{
        0,                      /* not used              */
        4,                      /* start                 */
        5,                      /* run                   */
        2,                      /* sleep                 */
        3,                      /* stop                  */
        1                       /* zombie                */
};

extern int rev_order;

/*
 *  proc_compares - comparison functions for "qsort"
 */

/*
 * First, the possible comparison keys.  These are defined in such a way
 * that they can be merely listed in the source code to define the actual
 * desired ordering.
 */

#define ORDERKEY_PCTCPU \
        if ((result = (int)(p2->p_pctcpu - p1->p_pctcpu)) == 0)
#define ORDERKEY_CPUTIME \
        if ((result = p2->p_rtime_sec - p1->p_rtime_sec) == 0) \
                if ((result = p2->p_rtime_usec - p1->p_rtime_usec) == 0)
#define ORDERKEY_STATE \
        if ((result = sorted_state[(unsigned char)p2->p_stat] - \
            sorted_state[(unsigned char)p1->p_stat])  == 0)
#define ORDERKEY_PRIO \
        if ((result = p2->p_priority - p1->p_priority) == 0)
#define ORDERKEY_RSSIZE \
        if ((result = p2->p_vm_rssize - p1->p_vm_rssize) == 0)
#define ORDERKEY_MEM \
        if ((result = PROCSIZE(p2) - PROCSIZE(p1)) == 0)
#define ORDERKEY_PID \
        if ((result = p1->p_pid - p2->p_pid) == 0)
#define ORDERKEY_CMD \
        if ((result = strcmp(p1->p_comm, p2->p_comm)) == 0)

/* remove one level of indirection and set sort order */
#define SETORDER do { \
                if (rev_order) { \
                        p1 = *(struct kinfo_proc **) v2; \
                        p2 = *(struct kinfo_proc **) v1; \
                } else { \
                        p1 = *(struct kinfo_proc **) v1; \
                        p2 = *(struct kinfo_proc **) v2; \
                } \
        } while (0)

/* compare_cpu - the comparison function for sorting by cpu percentage */
static int
compare_cpu(const void *v1, const void *v2)
{
        struct kinfo_proc *p1, *p2;
        int result;

        SETORDER;

        ORDERKEY_PCTCPU
        ORDERKEY_CPUTIME
        ORDERKEY_STATE
        ORDERKEY_PRIO
        ORDERKEY_RSSIZE
        ORDERKEY_MEM
                ;
        return (result);
}

/* compare_size - the comparison function for sorting by total memory usage */
static int
compare_size(const void *v1, const void *v2)
{
        struct kinfo_proc *p1, *p2;
        int result;

        SETORDER;

        ORDERKEY_MEM
        ORDERKEY_RSSIZE
        ORDERKEY_PCTCPU
        ORDERKEY_CPUTIME
        ORDERKEY_STATE
        ORDERKEY_PRIO
                ;
        return (result);
}

/* compare_res - the comparison function for sorting by resident set size */
static int
compare_res(const void *v1, const void *v2)
{
        struct kinfo_proc *p1, *p2;
        int result;

        SETORDER;

        ORDERKEY_RSSIZE
        ORDERKEY_MEM
        ORDERKEY_PCTCPU
        ORDERKEY_CPUTIME
        ORDERKEY_STATE
        ORDERKEY_PRIO
                ;
        return (result);
}

/* compare_time - the comparison function for sorting by CPU time */
static int
compare_time(const void *v1, const void *v2)
{
        struct kinfo_proc *p1, *p2;
        int result;

        SETORDER;

        ORDERKEY_CPUTIME
        ORDERKEY_PCTCPU
        ORDERKEY_STATE
        ORDERKEY_PRIO
        ORDERKEY_MEM
        ORDERKEY_RSSIZE
                ;
        return (result);
}

/* compare_prio - the comparison function for sorting by CPU time */
static int
compare_prio(const void *v1, const void *v2)
{
        struct kinfo_proc *p1, *p2;
        int result;

        SETORDER;

        ORDERKEY_PRIO
        ORDERKEY_PCTCPU
        ORDERKEY_CPUTIME
        ORDERKEY_STATE
        ORDERKEY_RSSIZE
        ORDERKEY_MEM
                ;
        return (result);
}

static int
compare_pid(const void *v1, const void *v2)
{
        struct kinfo_proc *p1, *p2;
        int result;

        SETORDER;

        ORDERKEY_PID
        ORDERKEY_PCTCPU
        ORDERKEY_CPUTIME
        ORDERKEY_STATE
        ORDERKEY_PRIO
        ORDERKEY_RSSIZE
        ORDERKEY_MEM
                ;
        return (result);
}

static int
compare_cmd(const void *v1, const void *v2)
{
        struct kinfo_proc *p1, *p2;
        int result;

        SETORDER;

        ORDERKEY_CMD
        ORDERKEY_PCTCPU
        ORDERKEY_CPUTIME
        ORDERKEY_STATE
        ORDERKEY_PRIO
        ORDERKEY_RSSIZE
        ORDERKEY_MEM
                ;
        return (result);
}


int (*proc_compares[])(const void *, const void *) = {
        compare_cpu,
        compare_size,
        compare_res,
        compare_time,
        compare_prio,
        compare_pid,
        compare_cmd,
        NULL
};

/*
 * proc_owner(pid) - returns the uid that owns process "pid", or -1 if
 *              the process does not exist.
 *              It is EXTREMELY IMPORTANT that this function work correctly.
 *              If top runs setuid root (as in SVR4), then this function
 *              is the only thing that stands in the way of a serious
 *              security problem.  It validates requests for the "kill"
 *              and "renice" commands.
 */
uid_t
proc_owner(pid_t pid)
{
        struct kinfo_proc **prefp, *pp;
        int cnt;

        prefp = pref;
        cnt = pref_len;
        while (--cnt >= 0) {
                pp = *prefp++;
                if (pp->p_pid == pid)
                        return ((uid_t)pp->p_ruid);
        }
        return (uid_t)(-1);
}

/*
 * swapmode is rewritten by Tobias Weingartner <weingart@openbsd.org>
 * to be based on the new swapctl(2) system call.
 */
static int
swapmode(int *used, int *total)
{
        struct swapent *swdev;
        int nswap, rnswap, i;

        nswap = swapctl(SWAP_NSWAP, 0, 0);
        if (nswap == 0)
                return 0;

        swdev = calloc(nswap, sizeof(*swdev));
        if (swdev == NULL)
                return 0;

        rnswap = swapctl(SWAP_STATS, swdev, nswap);
        if (rnswap == -1) {
                free(swdev);
                return 0;
        }

        /* if rnswap != nswap, then what? */

        /* Total things up */
        *total = *used = 0;
        for (i = 0; i < nswap; i++) {
                if (swdev[i].se_flags & SWF_ENABLE) {
                        *used += (swdev[i].se_inuse / (1024 / DEV_BSIZE));
                        *total += (swdev[i].se_nblks / (1024 / DEV_BSIZE));
                }
        }
        free(swdev);
        return 1;
}