/*-
 * SPDX-License-Identifier: BSD-3-Clause
 *
 * Copyright (c) 1993, John Brezak
 * 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. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``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 REGENTS OR CONTRIBUTORS 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.
 */

#ifdef DEBUG
#include <errno.h>
#endif
#include <stdio.h>
#include <string.h>
#include <sys/param.h>
#include <sys/stat.h>
#include <stdlib.h>
#include <syslog.h>
#include <utmpx.h>
#ifdef XIDLE
#include <setjmp.h>
#include <X11/Xlib.h>
#include <X11/extensions/xidle.h>
#endif
#include <rpcsvc/rnusers.h>

#include "extern.h"

#ifndef _PATH_DEV
#define _PATH_DEV "/dev"
#endif

static utmpidle utmp_idle[MAXUSERS];
static utmp old_utmp[MAXUSERS];
static struct utmpx utmp_list[MAXUSERS];

#ifdef XIDLE
static Display *dpy;

static jmp_buf openAbort;

static void
abortOpen(void)
{
    longjmp (openAbort, 1);
}

XqueryIdle(char *display)
{
        int first_event, first_error;
        Time IdleTime;

        (void) signal (SIGALRM, abortOpen);
        (void) alarm ((unsigned) 10);
        if (!setjmp (openAbort)) {
                if (!(dpy= XOpenDisplay(display))) {
                        syslog(LOG_ERR, "Cannot open display %s", display);
                        return(-1);
                }
                if (XidleQueryExtension(dpy, &first_event, &first_error)) {
                        if (!XGetIdleTime(dpy, &IdleTime)) {
                                syslog(LOG_ERR, "%s: unable to get idle time", display);
                                return(-1);
                        }
                } else {
                        syslog(LOG_ERR, "%s: Xidle extension not loaded", display);
                        return(-1);
                }
                XCloseDisplay(dpy);
        } else {
                syslog(LOG_ERR, "%s: server grabbed for over 10 seconds", display);
                return(-1);
        }
        (void) signal (SIGALRM, SIG_DFL);
        (void) alarm ((unsigned) 0);

        IdleTime /= 1000;
        return((IdleTime + 30) / 60);
}
#endif

static u_int
getidle(const char *tty, const char *display __unused)
{
        struct stat st;
        char ttyname[PATH_MAX];
        time_t now;
        u_long idle;

        /*
         * If this is an X terminal or console, then try the
         * XIdle extension
         */
#ifdef XIDLE
        if (display && *display && (idle = XqueryIdle(display)) >= 0)
                return(idle);
#endif
        idle = 0;
        if (*tty == 'X') {
                u_long kbd_idle, mouse_idle;
#if     !defined(__FreeBSD__)
                kbd_idle = getidle("kbd", NULL);
#else
                kbd_idle = getidle("vga", NULL);
#endif
                mouse_idle = getidle("mouse", NULL);
                idle = (kbd_idle < mouse_idle)?kbd_idle:mouse_idle;
        } else {
                sprintf(ttyname, "%s/%s", _PATH_DEV, tty);
                if (stat(ttyname, &st) < 0) {
#ifdef DEBUG
                        printf("%s: %s\n", ttyname, strerror(errno));
#endif
                        return(-1);
                }
                time(&now);
#ifdef DEBUG
                printf("%s: now=%d atime=%d\n", ttyname, now,
                       st.st_atime);
#endif
                idle = now - st.st_atime;
                idle = (idle + 30) / 60; /* secs->mins */
        }

        return(idle);
}

static utmpidlearr *
do_names_2(void)
{
        static utmpidlearr ut;
        struct utmpx *usr;
        int nusers = 0;

        memset(&ut, 0, sizeof(ut));
        ut.utmpidlearr_val = &utmp_idle[0];

        setutxent();
        while ((usr = getutxent()) != NULL && nusers < MAXUSERS) {
                if (usr->ut_type != USER_PROCESS)
                        continue;

                memcpy(&utmp_list[nusers], usr, sizeof(*usr));
                utmp_idle[nusers].ui_utmp.ut_time = usr->ut_tv.tv_sec;
                utmp_idle[nusers].ui_idle =
                    getidle(usr->ut_line, usr->ut_host);
                utmp_idle[nusers].ui_utmp.ut_line =
                    utmp_list[nusers].ut_line;
                utmp_idle[nusers].ui_utmp.ut_name =
                    utmp_list[nusers].ut_user;
                utmp_idle[nusers].ui_utmp.ut_host =
                    utmp_list[nusers].ut_host;

                nusers++;
        }
        endutxent();

        ut.utmpidlearr_len = nusers;
        return(&ut);
}

static int *
rusers_num(void *argp __unused, struct svc_req *rqstp __unused)
{
        static int num_users = 0;
        struct utmpx *usr;
 
        setutxent();
        while ((usr = getutxent()) != NULL) {
                if (usr->ut_type != USER_PROCESS)
                        continue;
                num_users++;
        }
        endutxent();
 
        return(&num_users);
}

static utmparr *
do_names_1(void)
{
        utmpidlearr *utidle;
        static utmparr ut;
        unsigned int i;

        bzero((char *)&ut, sizeof(ut));

        utidle = do_names_2();
        if (utidle) {
                ut.utmparr_len = utidle->utmpidlearr_len;
                ut.utmparr_val = &old_utmp[0];
                for (i = 0; i < ut.utmparr_len; i++)
                        bcopy(&utmp_idle[i].ui_utmp, &old_utmp[i],
                              sizeof(old_utmp[0]));

        }

        return(&ut);
}

utmpidlearr *
rusersproc_names_2_svc(void *argp __unused, struct svc_req *rqstp __unused)
{

        return (do_names_2());
}

utmpidlearr *
rusersproc_allnames_2_svc(void *argp __unused, struct svc_req *rqstp __unused)
{

        return (do_names_2());
}

utmparr *
rusersproc_names_1_svc(void *argp __unused, struct svc_req *rqstp __unused)
{

        return (do_names_1());
}

utmparr *
rusersproc_allnames_1_svc(void *argp __unused, struct svc_req *rqstp __unused)
{

        return (do_names_1());
}

typedef void *(*rusersproc_t)(void *, struct svc_req *);

void
rusers_service(struct svc_req *rqstp, SVCXPRT *transp)
{
        union {
                int fill;
        } argument;
        char *result;
        xdrproc_t xdr_argument, xdr_result;
        rusersproc_t local;

        switch (rqstp->rq_proc) {
        case NULLPROC:
                (void)svc_sendreply(transp, (xdrproc_t)xdr_void, NULL);
                goto leave;

        case RUSERSPROC_NUM:
                xdr_argument = (xdrproc_t)xdr_void;
                xdr_result = (xdrproc_t)xdr_int;
                local = (rusersproc_t)rusers_num;
                break;

        case RUSERSPROC_NAMES:
                xdr_argument = (xdrproc_t)xdr_void;
                xdr_result = (xdrproc_t)xdr_utmpidlearr;
                switch (rqstp->rq_vers) {
                case RUSERSVERS_ORIG:
                        local = (rusersproc_t)rusersproc_names_1_svc;
                        break;
                case RUSERSVERS_IDLE:
                        local = (rusersproc_t)rusersproc_names_2_svc;
                        break;
                default:
                        svcerr_progvers(transp, RUSERSVERS_ORIG, RUSERSVERS_IDLE);
                        goto leave;
                        /*NOTREACHED*/
                }
                break;

        case RUSERSPROC_ALLNAMES:
                xdr_argument = (xdrproc_t)xdr_void;
                xdr_result = (xdrproc_t)xdr_utmpidlearr;
                switch (rqstp->rq_vers) {
                case RUSERSVERS_ORIG:
                        local = (rusersproc_t)rusersproc_allnames_1_svc;
                        break;
                case RUSERSVERS_IDLE:
                        local = (rusersproc_t)rusersproc_allnames_2_svc;
                        break;
                default:
                        svcerr_progvers(transp, RUSERSVERS_ORIG, RUSERSVERS_IDLE);
                        goto leave;
                        /*NOTREACHED*/
                }
                break;

        default:
                svcerr_noproc(transp);
                goto leave;
        }
        bzero(&argument, sizeof(argument));
        if (!svc_getargs(transp, (xdrproc_t)xdr_argument, &argument)) {
                svcerr_decode(transp);
                goto leave;
        }
        result = (*local)(&argument, rqstp);
        if (result != NULL &&
            !svc_sendreply(transp, (xdrproc_t)xdr_result, result)) {
                svcerr_systemerr(transp);
        }
        if (!svc_freeargs(transp, (xdrproc_t)xdr_argument, &argument)) {
                syslog(LOG_ERR, "unable to free arguments");
                exit(1);
        }
leave:
        if (from_inetd)
                exit(0);
}