/*	$NetBSD: swaplist.c,v 1.23 2026/02/16 23:18:54 kre Exp $	*/

/*
 * Copyright (c) 1997 Matthew R. Green
 * 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.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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.
 */
#include <sys/cdefs.h>

#ifndef lint
__RCSID("$NetBSD: swaplist.c,v 1.23 2026/02/16 23:18:54 kre Exp $");
#endif


#include <sys/param.h>
#include <sys/stat.h>
#include <sys/swap.h>

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

#define	dbtoqb(b) dbtob((int64_t)(b))

/*
 * NOTE:  This file is separate from swapctl.c so that pstat can grab it.
 */

#include "swapctl.h"

static int
swapent_cmp(const void *a, const void *b)
{
	const struct swapent *p, *q;
	size_t l1, l2;

	p = (const struct swapent *)a;
	q = (const struct swapent *)b;

	/*
	 * Sort by priority first, highest priority first
	 * (which means increasing order of the priority field)
	 */
	if (p->se_priority != q->se_priority)
		return p->se_priority - q->se_priority;

	/*
	 * Then sort by device name.  These are arbitrary,
	 * and no order really makes more sense than any
	 * other, but the kernel's lists of swap devices at
	 * the same priority are reordered at will, but for
	 * a better human experience, keeping a constant
	 * ordering is better, this should achieve that.
	 */
	if ((l1 = strlen(p->se_path)) != (l2 = strlen(q->se_path)))
		return l1 > l2 ? 1 : -1;
	return strcmp(p->se_path, q->se_path);
}

int
list_swap(int pri, int kflag, int pflag, int tflag, int dolong, int hflag)
{
	struct	swapent *sep, *fsep;
	long	blocksize;
	char	szbuf[5], usbuf[5], avbuf[5]; /* size, used, avail */
	const	char *header, *suff;
	size_t	l;
	int	hlen, size, inuse, ncounted, pathmax, cw;
	int	rnswap, nswap = swapctl(SWAP_NSWAP, 0, 0), i;
	int64_t	totalsize, totalinuse;

	if (nswap < 1) {
		puts("no swap devices configured");
		return 0;
	}

	/*
	 * treat the value from swapctl(SWAP_NSWAP) as a hint,
	 * as the value might have changed (swap devices added
	 * or removed) between when that info was obtained, and
	 * when we actually request the stats.
	 *
	 * Assume it will be increasing (if descreasing no harm)
	 * and allow for it to have grown a reasonable amount.
	 *
	 * Then we simply use however many swap table entries
	 * the kernel returns from swapctl(SWAP_STATS), be that
	 * more or less than swapctl(SWAP_NSWAP) claimed, or
	 * as many as or less than we have allocated space for.
	 * If the kernel has added even more than the guess
	 * below, then we will not get all of them.   Oh well...
	 */
	nswap += 3;

	fsep = sep = (struct swapent *)malloc(nswap * sizeof(*sep));
	if (sep == NULL)
		err(1, "malloc");
	rnswap = swapctl(SWAP_STATS, (void *)sep, nswap);
	if (rnswap < 0)
		err(1, "SWAP_STATS");

	if (rnswap == 0) {
		puts("no swap devices configured");
		return 0;
	}

	/* keep the list ordered, as long as it remains stable */
	if (rnswap > 1)
		qsort(sep, rnswap, sizeof(struct swapent), swapent_cmp);

	pathmax = 11;
	switch (kflag) {
		case 1:
			header = "1K-blocks";
			blocksize = 1024;
			suff = "KBytes";
			break;
		case 2:
			suff = "MBytes";
			header = "1M-blocks";
			blocksize = 1024 * 1024;
			break;
		case 3:
			header = "1G-blocks";
			blocksize = 1024 * 1024 * 1024;
			suff = "GBytes";
			break;
		default:
			suff = "blocks";
			if (!hflag) {
				header = getbsize(&hlen, &blocksize);
			} else {
				header = "Size";
				blocksize = 1; suff = ""; /* unused */
			}
			break;
	}
	if (hflag || kflag)
		hlen = strlen(header);

	cw = 8;
	if (dolong && tflag == 0) {
		totalsize = 0;
		for (i = rnswap; i-- > 0; sep++) {
			if ((size_t)pathmax < (l = strlen(sep->se_path)))
				pathmax = l;
			totalsize += sep->se_nblks;
		}
		sep = fsep;

		if (!hflag) {
			totalsize = dbtoqb(totalsize) / blocksize;
			if (totalsize > 9999999990)
				cw = 11;
			else if (totalsize > 999999990)
				cw = 10;
			else if (totalsize > 99999990)
				cw = 9;

			if (hlen < cw)
				hlen = cw;
		}

		/*
		 * The intent here is that for the 3 size columns,
		 * the units digit (or scale letter with -h) is always
		 * under the rightmost character of its heading, the
		 * '%' character is under the 't' in "Capacity" and
		 * the units digit of the priority is under the 'o'
		 * of "Priority".    This looks reasonably good.
		 */
		(void)printf("%-*s %*s %*s %*s %8s  %s\n",
		    pathmax, "Device", hlen, header, cw, "Used",
		    cw, "Avail", "Capacity", "Priority");
	}
	totalsize = totalinuse = ncounted = 0;
	for (; rnswap-- > 0; sep++) {
		if (pflag && sep->se_priority != pri)
			continue;
		ncounted++;
		size = sep->se_nblks;
		inuse = sep->se_inuse;
		totalsize += size;
		totalinuse += inuse;

		if (dolong && tflag == 0) {
			if (hflag == 0) {
				(void)printf("%-*s %*ld ",
				    pathmax, sep->se_path, hlen,
				    (long)(dbtoqb(size) / blocksize));

				(void)printf("%*ld %*ld  %5.0f%%    %3d\n",
				    cw, (long)(dbtoqb(inuse) / blocksize), cw,
				    (long)(dbtoqb(size - inuse) / blocksize),
				    (double)inuse / (double)size * 100.0,
				    sep->se_priority);
			} else {
				if ((humanize_number(szbuf, sizeof(szbuf),
				    (dbtoqb(size)), "", HN_AUTOSCALE,
				    (HN_DECIMAL | HN_B | HN_NOSPACE))) == -1)
					err(1, "humanize_number");
				if ((humanize_number(usbuf, sizeof(usbuf),
				    (dbtoqb(inuse)), "", HN_AUTOSCALE,
				    (HN_DECIMAL | HN_B | HN_NOSPACE))) == -1)
					err(1, "humanize_number");
				if ((humanize_number(avbuf, sizeof(avbuf),
				    (dbtoqb(size-inuse)), "", HN_AUTOSCALE,
				    (HN_DECIMAL | HN_B | HN_NOSPACE))) == -1)
					err(1, "humanize_number");
				(void)printf("%-*s %*s ",
				    pathmax, sep->se_path, hlen, szbuf);

				(void)printf("%*s %*s  %5.0f%%    %3d\n",
				    cw, usbuf, cw, avbuf,
				    (double)inuse / (double)size * 100.0,
				    sep->se_priority);
			}
		}
	}
	if (tflag) {
		if (hflag) {
			if ((humanize_number(usbuf, sizeof(usbuf),
			    (dbtoqb(totalinuse)), "", HN_AUTOSCALE,
			    (HN_DECIMAL | HN_B | HN_NOSPACE))) == -1)
				err(1, "humanize_number");
			if ((humanize_number(szbuf, sizeof(szbuf),
			    (dbtoqb(totalsize)), "", HN_AUTOSCALE,
			    (HN_DECIMAL | HN_B | HN_NOSPACE))) == -1)
				err(1, "humanize_number");
			(void)printf("%s/%s swap space\n", usbuf, szbuf);
		} else {
			(void)printf("%ld/%ld %s swap space\n",
				(long)(dbtoqb(totalinuse) / blocksize),
				(long)(dbtoqb(totalsize) / blocksize),
				suff);
		}
	} else if (dolong == 0) {
		if (hflag) {
			if ((humanize_number(szbuf, sizeof(szbuf),
			    (dbtoqb(totalsize)), "", HN_AUTOSCALE,
			    (HN_DECIMAL | HN_B | HN_NOSPACE))) == -1)
				err(1, "humanize_number");
			if ((humanize_number(usbuf, sizeof(usbuf),
			    (dbtoqb(totalinuse)), "", HN_AUTOSCALE,
			    (HN_DECIMAL | HN_B | HN_NOSPACE))) == -1)
				err(1, "humanize_number");
			if ((humanize_number(avbuf, sizeof(avbuf),
			    (dbtoqb(totalsize-totalinuse)), "", HN_AUTOSCALE,
			    (HN_DECIMAL | HN_B | HN_NOSPACE))) == -1)
				err(1, "humanize_number");
			(void)printf(
			    "total: %s allocated, %s used, %s available.\n",
			    szbuf, usbuf, avbuf);
		} else {
		    printf("total: %ld %s allocated, %ld %s used, "
			   "%ld %s available\n",
		    (long)(dbtoqb(totalsize) / blocksize), suff,
		    (long)(dbtoqb(totalinuse) / blocksize), suff,
		    (long)(dbtoqb(totalsize - totalinuse) / blocksize), suff);
		}
	} else if (ncounted > 1) {
		if (hflag) {
			if ((humanize_number(szbuf, sizeof(szbuf),
			    (dbtoqb(totalsize)), "", HN_AUTOSCALE,
			    (HN_DECIMAL | HN_B | HN_NOSPACE))) == -1)
				err(1, "humanize_number");
			if ((humanize_number(usbuf, sizeof(usbuf),
			    (dbtoqb(totalinuse)), "", HN_AUTOSCALE,
			    (HN_DECIMAL | HN_B | HN_NOSPACE))) == -1)
				err(1, "humanize_number");
			if ((humanize_number(avbuf, sizeof(avbuf),
			    (dbtoqb(totalsize-totalinuse)), "", HN_AUTOSCALE,
			    (HN_DECIMAL | HN_B | HN_NOSPACE))) == -1)
				err(1, "humanize_number");
			(void)printf("%-*s %*s %*s %*s  %5.0f%%\n",
			    pathmax, "Total", hlen, szbuf, cw, usbuf, cw, avbuf,
			    (double)(totalinuse) / (double)totalsize * 100.0);
		} else {
			(void)printf("%-*s %*ld %*ld %*ld  %5.0f%%\n",
			    pathmax, "Total", hlen,
			    (long)(dbtoqb(totalsize) / blocksize),
			    cw, (long)(dbtoqb(totalinuse) / blocksize), cw,
			    (long)(dbtoqb(totalsize - totalinuse) / blocksize),
			    (double)(totalinuse) / (double)totalsize * 100.0);
		}
	}
	if (fsep)
		(void)free(fsep);

	return 1;
}