/*      $OpenBSD: apmd.c,v 1.113 2025/05/24 02:56:41 kn Exp $   */

/*
 *  Copyright (c) 1995, 1996 John T. Kohl
 *  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 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/stat.h>
#include <sys/ioctl.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <sys/wait.h>
#include <sys/event.h>
#include <sys/time.h>
#include <sys/sysctl.h>
#include <assert.h>
#include <stdarg.h>
#include <stdio.h>
#include <syslog.h>
#include <fcntl.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <signal.h>
#include <errno.h>
#include <err.h>
#include <limits.h>
#include <machine/apmvar.h>

#include "pathnames.h"
#include "apm-proto.h"

#define AUTO_SUSPEND 1
#define AUTO_HIBERNATE 2

int debug = 0;

extern char *__progname;

void usage(void);
int power_status(int fd, int force, struct apm_power_info *pinfo);
int bind_socket(const char *sn);
void handle_client(int sock_fd, int ctl_fd);
void warnlow(void);
int suspend(int ctl_fd);
int stand_by(int ctl_fd);
int hibernate(int ctl_fd);
void resumed(int ctl_fd);
void setperfpolicy(char *policy);
void sigexit(int signo);
void do_etc_file(const char *file);
void error(const char *fmt, const char *arg);
void set_driver_messages(int fd, int mode);

void
sigexit(int signo)
{
        _exit(1);
}

void
logmsg(int prio, const char *msg, ...)
{
        va_list ap;

        va_start(ap, msg);
        if (debug) {
                vfprintf(stderr, msg, ap);
                fprintf(stderr, "\n");
        } else {
                vsyslog(prio, msg, ap);
        }
        va_end(ap);
}

void
usage(void)
{
        fprintf(stderr,
            "usage: %s [-AadHLs] [-f devname] [-S sockname] [-t seconds]"
            " [-w percent]\n"
            "\t[-Z percent] [-z percent]\n", __progname);
        exit(1);
}

void
error(const char *fmt, const char *arg)
{
        char buf[128];

        if (debug)
                err(1, fmt, arg);
        else {
                strlcpy(buf, fmt, sizeof(buf));
                strlcat(buf, ": %m", sizeof(buf));
                syslog(LOG_ERR, buf, arg);
                exit(1);
        }
}


/*
 * tell the driver if it should display messages or not.
 */
void
set_driver_messages(int fd, int mode)
{
        if (ioctl(fd, APM_IOC_PRN_CTL, &mode) == -1)
                logmsg(LOG_DEBUG, "can't disable driver messages, error: %s",
                    strerror(errno));
}

int
power_status(int fd, int force, struct apm_power_info *pinfo)
{
        struct apm_power_info bstate;
        static struct apm_power_info last;
        int acon = 0, priority = LOG_NOTICE;

        if (fd == -1) {
                if (pinfo) {
                        bstate.battery_state = 255;
                        bstate.ac_state = 255;
                        bstate.battery_life = 0;
                        bstate.minutes_left = -1;
                        *pinfo = bstate;
                }

                return 0;
        }

        if (ioctl(fd, APM_IOC_GETPOWER, &bstate) == 0) {
        /* various conditions under which we report status:  something changed
         * enough since last report, or asked to force a print */
                if (bstate.ac_state == APM_AC_ON)
                        acon = 1;
                if (bstate.battery_state == APM_BATT_CRITICAL &&
                    bstate.battery_state != last.battery_state)
                        priority = LOG_EMERG;
                if (force ||
                    bstate.ac_state != last.ac_state ||
                    bstate.battery_state != last.battery_state ||
                    ((bstate.battery_state != APM_BATT_CHARGING) &&
                     (bstate.minutes_left && bstate.minutes_left < 15)) ||
                    abs(bstate.battery_life - last.battery_life) >= 10) {
                        if ((int)bstate.minutes_left > 0)
                                logmsg(priority, "battery status: %s. "
                                    "external power status: %s. "
                                    "estimated battery life %d%% "
                                    "(%u minutes %s time estimate)",
                                    battstate(bstate.battery_state),
                                    ac_state(bstate.ac_state),
                                    bstate.battery_life,
                                    bstate.minutes_left,
                                    (bstate.battery_state == APM_BATT_CHARGING)
                                        ? "recharge" : "life");
                        else
                                logmsg(priority, "battery status: %s. "
                                    "external power status: %s. "
                                    "estimated battery life %d%%",
                                    battstate(bstate.battery_state),
                                    ac_state(bstate.ac_state),
                                    bstate.battery_life);
                        last = bstate;
                }
                if (pinfo)
                        *pinfo = bstate;
        } else
                logmsg(LOG_ERR, "cannot fetch power status: %s", strerror(errno));

        return acon;
}

int
bind_socket(const char *sockname)
{
        struct sockaddr_un s_un;
        mode_t old_umask;
        int sock;

        sock = socket(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC, 0);
        if (sock == -1)
                error("cannot create local socket", NULL);

        s_un.sun_family = AF_UNIX;
        strlcpy(s_un.sun_path, sockname, sizeof(s_un.sun_path));

        /* remove it if present, we're moving in */
        (void) remove(sockname);

        old_umask = umask(077);
        if (bind(sock, (struct sockaddr *)&s_un, sizeof(s_un)) == -1)
                error("cannot bind on APM socket", NULL);
        umask(old_umask);
        if (chmod(sockname, 0660) == -1 || chown(sockname, 0, 0) == -1)
                error("cannot set socket mode/owner/group to 660/0/0", NULL);

        listen(sock, 1);

        return sock;
}

void
handle_client(int sock_fd, int ctl_fd)
{
        /* accept a handle from the client, process it, then clean up */
        int cli_fd;
        struct sockaddr_un from;
        socklen_t fromlen;
        struct apm_command cmd;
        struct apm_reply reply;
        int perfpol_mib[] = { CTL_HW, HW_PERFPOLICY };
        char perfpol[32];
        size_t perfpol_sz = sizeof(perfpol);
        int cpuspeed_mib[] = { CTL_HW, HW_CPUSPEED };
        int cpuspeed = 0;
        size_t cpuspeed_sz = sizeof(cpuspeed);

        fromlen = sizeof(from);
        cli_fd = accept(sock_fd, (struct sockaddr *)&from, &fromlen);
        if (cli_fd == -1) {
                logmsg(LOG_INFO, "client accept failure: %s", strerror(errno));
                return;
        }

        if (recv(cli_fd, &cmd, sizeof(cmd), 0) != sizeof(cmd)) {
                (void) close(cli_fd);
                logmsg(LOG_INFO, "client size botch");
                return;
        }

        if (cmd.vno != APMD_VNO) {
                close(cli_fd);                  /* terminate client */
                /* no error message, just drop it. */
                return;
        }

        bzero(&reply, sizeof(reply));
        power_status(ctl_fd, 0, &reply.batterystate);
        switch (cmd.action) {
        case SUSPEND:
                reply.newstate = SUSPENDING;
                reply.error = suspend(ctl_fd);
                break;
        case STANDBY:
                reply.newstate = STANDING_BY;
                reply.error = stand_by(ctl_fd);
                break;
        case HIBERNATE:
                reply.newstate = HIBERNATING;
                reply.error = hibernate(ctl_fd);
                break;
        case SETPERF_LOW:
                reply.newstate = NORMAL;
                logmsg(LOG_NOTICE, "setting hw.perfpolicy to low");
                setperfpolicy("low");
                break;
        case SETPERF_HIGH:
                reply.newstate = NORMAL;
                logmsg(LOG_NOTICE, "setting hw.perfpolicy to high");
                setperfpolicy("high");
                break;
        case SETPERF_AUTO:
                reply.newstate = NORMAL;
                logmsg(LOG_NOTICE, "setting hw.perfpolicy to auto");
                setperfpolicy("auto");
                break;
        default:
                reply.newstate = NORMAL;
                break;
        }

        reply.perfmode = PERF_NONE;
        if (sysctl(perfpol_mib, 2, perfpol, &perfpol_sz, NULL, 0) == -1)
                logmsg(LOG_INFO, "cannot read hw.perfpolicy");
        else {
                if (strcmp(perfpol, "manual") == 0 ||
                    strcmp(perfpol, "high") == 0) {
                        reply.perfmode = PERF_MANUAL;
                } else if (strcmp(perfpol, "auto") == 0)
                        reply.perfmode = PERF_AUTO;
        }

        if (sysctl(cpuspeed_mib, 2, &cpuspeed, &cpuspeed_sz, NULL, 0) == -1) {
                logmsg(LOG_INFO, "cannot read hw.cpuspeed");
                cpuspeed = 0;
        }
        reply.cpuspeed = cpuspeed;
        reply.vno = APMD_VNO;
        if (send(cli_fd, &reply, sizeof(reply), 0) != sizeof(reply))
                logmsg(LOG_INFO, "reply to client botched");
        close(cli_fd);
}

/*
 * Refresh the random file read by the bootblocks, and remove the +t bit
 * which the bootblock use to track "reuse of the file".
 */
void
fixrandom(void)
{
        char buf[512];
        int fd;

        fd = open("/etc/random.seed", O_WRONLY);
        if (fd != -1) {
                arc4random_buf(buf, sizeof buf);
                write(fd, buf, sizeof buf);
                fchmod(fd, 0600);
                close(fd);
        }
}

void
warnlow(void)
{
        do_etc_file(_PATH_APM_ETC_WARNLOW);
}

int
suspend(int ctl_fd)
{
        int error = 0;

        logmsg(LOG_NOTICE, "system suspending");
        power_status(ctl_fd, 1, NULL);
        fixrandom();
        do_etc_file(_PATH_APM_ETC_SUSPEND);
        sync();
        sleep(1);

        if (ioctl(ctl_fd, APM_IOC_SUSPEND, 0) == -1) {
                error = errno;
                logmsg(LOG_WARNING, "%s: %s", __func__, strerror(errno));
        }

        return error;
}

int
stand_by(int ctl_fd)
{
        int error = 0;

        logmsg(LOG_NOTICE, "system entering standby");
        power_status(ctl_fd, 1, NULL);
        fixrandom();
        do_etc_file(_PATH_APM_ETC_STANDBY);
        sync();
        sleep(1);

        if (ioctl(ctl_fd, APM_IOC_STANDBY, 0) == -1) {
                error = errno;
                logmsg(LOG_WARNING, "%s: %s", __func__, strerror(errno));
        }

        return error;
}

int
hibernate(int ctl_fd)
{
        int error = 0;

        logmsg(LOG_NOTICE, "system hibernating");
        power_status(ctl_fd, 1, NULL);
        fixrandom();
        do_etc_file(_PATH_APM_ETC_HIBERNATE);
        sync();
        sleep(1);

        if (ioctl(ctl_fd, APM_IOC_HIBERNATE, 0) == -1) {
                error = errno;
                logmsg(LOG_WARNING, "%s: %s", __func__, strerror(errno));
        }

        return error;
}

void
resumed(int ctl_fd)
{
        do_etc_file(_PATH_APM_ETC_RESUME);
        logmsg(LOG_NOTICE, "system resumed from sleep");
        power_status(ctl_fd, 1, NULL);
}

#define TIMO (10*60)                    /* 10 minutes */
#define AUTOACTION_GRACE_PERIOD (60)    /* 1 minute after resume */
#define WARNING_GRACE_PERIOD    (2*60)  /* 2 minutes after last warning */

int
main(int argc, char *argv[])
{
        const char *fname = _PATH_APM_CTLDEV;
        int ctl_fd, sock_fd, ch, warnlows, suspends, standbys, hibernates, resumes;
        int autoaction = 0, autoaction_inflight = 0;
        int autolimit = 0, warnlimit = 0;
        int statonly = 0;
        int powerstatus = 0, powerbak = 0, powerchange = 0;
        int noacsleep = 0;
        struct timespec ts = {TIMO, 0}, sts = {0, 0};
        struct timespec last_resume = { 0, 0 };
        struct apm_power_info pinfo;
        const char *sockname = _PATH_APM_SOCKET;
        const char *errstr;
        int kq, nchanges;
        struct kevent ev[2];
        int doperf = PERF_NONE;

        while ((ch = getopt(argc, argv, "aACdHLsf:t:S:w:z:Z:")) != -1)
                switch(ch) {
                case 'a':
                        noacsleep = 1;
                        break;
                case 'd':
                        debug = 1;
                        break;
                case 'f':
                        fname = optarg;
                        break;
                case 'S':
                        sockname = optarg;
                        break;
                case 't':
                        ts.tv_sec = strtonum(optarg, 1, LLONG_MAX, &errstr);
                        if (errstr != NULL)
                                errx(1, "number of seconds is %s: %s", errstr,
                                    optarg);
                        break;
                case 's':       /* status only */
                        statonly = 1;
                        break;
                case 'A':
                case 'C':
                        if (doperf != PERF_NONE)
                                usage();
                        doperf = PERF_AUTO;
                        setperfpolicy("auto");
                        break;
                case 'L':
                        if (doperf != PERF_NONE)
                                usage();
                        doperf = PERF_MANUAL;
                        setperfpolicy("low");
                        break;
                case 'H':
                        if (doperf != PERF_NONE)
                                usage();
                        doperf = PERF_MANUAL;
                        setperfpolicy("high");
                        break;
                case 'w':
                        warnlimit = strtonum(optarg, 1, 100, &errstr);
                        if (errstr != NULL)
                                errx(1, "battery percentage is %s: %s", errstr,
                                    optarg);
                        break;
                case 'Z':
                        autoaction = AUTO_HIBERNATE;
                        autolimit = strtonum(optarg, 1, 100, &errstr);
                        if (errstr != NULL)
                                errx(1, "battery percentage is %s: %s", errstr,
                                    optarg);
                        break;
                case 'z':
                        autoaction = AUTO_SUSPEND;
                        autolimit = strtonum(optarg, 1, 100, &errstr);
                        if (errstr != NULL)
                                errx(1, "battery percentage is %s: %s", errstr,
                                    optarg);
                        break;
                default:
                        usage();
                }

        argc -= optind;
        argv += optind;

        if (argc != 0)
                usage();

        if (doperf == PERF_NONE)
                doperf = PERF_MANUAL;

        if (debug == 0) {
                if (daemon(0, 0) == -1)
                        error("failed to daemonize", NULL);
                openlog(__progname, LOG_CONS, LOG_DAEMON);
                setlogmask(LOG_UPTO(LOG_NOTICE));
        }

        (void) signal(SIGTERM, sigexit);
        (void) signal(SIGHUP, sigexit);
        (void) signal(SIGINT, sigexit);

        if ((ctl_fd = open(fname, O_RDWR | O_CLOEXEC)) == -1) {
                if (errno != ENXIO && errno != ENOENT)
                        error("cannot open device file `%s'", fname);
        }

        sock_fd = bind_socket(sockname);

        power_status(ctl_fd, 1, &pinfo);

        if (statonly)
                exit(0);

        if (unveil(_PATH_APM_ETC_DIR, "rx") == -1)
                err(1, "unveil %s", _PATH_APM_ETC_DIR);
        if (unveil("/etc/random.seed", "w") == -1)
                err(1, "unveil /etc/random.seed");
        if (unveil(NULL, NULL) == -1)
                err(1, "unveil");

        set_driver_messages(ctl_fd, APM_PRINT_OFF);

        kq = kqueue();
        if (kq <= 0)
                error("kqueue", NULL);

        EV_SET(&ev[0], sock_fd, EVFILT_READ, EV_ADD | EV_ENABLE | EV_CLEAR,
            0, 0, NULL);
        if (ctl_fd == -1)
                nchanges = 1;
        else {
                EV_SET(&ev[1], ctl_fd, EVFILT_READ, EV_ADD | EV_ENABLE |
                    EV_CLEAR, 0, 0, NULL);
                nchanges = 2;
        }
        if (kevent(kq, ev, nchanges, NULL, 0, &sts) == -1)
                error("kevent", NULL);

        for (;;) {
                int rv, event, index;

                sts = ts;

                if ((rv = kevent(kq, NULL, 0, ev, 1, &sts)) == -1)
                        break;

                if (rv == 1 && ev->ident == sock_fd) {
                        handle_client(sock_fd, ctl_fd);
                        continue;
                }

                warnlows = suspends = standbys = hibernates = resumes = 0;

                if (rv == 0 && ctl_fd == -1) {
                        /* timeout and no way to query status */
                        continue;
                } else if (rv == 0) {
                        /* wakeup for timeout: take status */
                        event = APM_POWER_CHANGE;
                        index = -1;
                } else {
                        assert(rv == 1 && ev->ident == ctl_fd);
                        event = APM_EVENT_TYPE(ev->data);
                        index = APM_EVENT_INDEX(ev->data);
                }

                logmsg(LOG_DEBUG, "apmevent %04x index %d", event, index);

                switch (event) {
                case APM_SUSPEND_REQ:
                case APM_USER_SUSPEND_REQ:
                case APM_CRIT_SUSPEND_REQ:
                case APM_BATTERY_LOW:
                        suspends++;
                        break;
                case APM_USER_STANDBY_REQ:
                case APM_STANDBY_REQ:
                        standbys++;
                        break;
                case APM_USER_HIBERNATE_REQ:
                        hibernates++;
                        break;
                case APM_NORMAL_RESUME:
                case APM_CRIT_RESUME:
                case APM_SYS_STANDBY_RESUME:
                        powerbak = power_status(ctl_fd, 0, &pinfo);
                        if (powerstatus != powerbak) {
                                powerstatus = powerbak;
                                powerchange = 1;
                        }
                        clock_gettime(CLOCK_MONOTONIC, &last_resume);
                        autoaction_inflight = 0;
                        resumes++;
                        break;
                case APM_POWER_CHANGE:
                        powerbak = power_status(ctl_fd, 0, &pinfo);
                        if (powerstatus != powerbak) {
                                powerstatus = powerbak;
                                powerchange = 1;
                        }

                        if (!powerstatus && autoaction &&
                            autolimit > (int)pinfo.battery_life) {
                                struct timespec graceperiod, now;

                                graceperiod = last_resume;
                                graceperiod.tv_sec += AUTOACTION_GRACE_PERIOD;
                                clock_gettime(CLOCK_MONOTONIC, &now);

                                logmsg(LOG_NOTICE,
                                    "estimated battery life %d%%"
                                    " below configured limit %d%%%s%s",
                                    pinfo.battery_life, autolimit,
                                    !autoaction_inflight ? "" : ", in flight",
                                    timespeccmp(&now, &graceperiod, >) ?
                                        "" : ", grace period"
                                );

                                if (!autoaction_inflight &&
                                    timespeccmp(&now, &graceperiod, >)) {
                                        if (autoaction == AUTO_SUSPEND)
                                                suspends++;
                                        else
                                                hibernates++;
                                        /* Block autoaction until next resume */
                                        autoaction_inflight = 1;
                                }
                        } else if (!powerstatus && warnlimit > 0 &&
                            warnlimit > (int)pinfo.battery_life) {
                                static struct timespec last_warn = {0, 0};
                                struct timespec graceperiod_w, now_w;

                                graceperiod_w = last_warn;
                                graceperiod_w.tv_sec += WARNING_GRACE_PERIOD;
                                clock_gettime(CLOCK_MONOTONIC, &now_w);

                                if (timespeccmp(&now_w, &graceperiod_w, >)) {
                                        logmsg(LOG_NOTICE,
                                            "estimated battery life %d%%"
                                            " below configured limit %d%%",
                                            pinfo.battery_life, warnlimit);

                                        last_warn = now_w;
                                        warnlows++;
                                }
                        }
                        break;
                default:
                        ;
                }

                if ((standbys || suspends) && noacsleep &&
                    power_status(ctl_fd, 0, &pinfo))
                        logmsg(LOG_DEBUG, "no! sleep! till brooklyn!");
                else if (warnlows)
                        warnlow();
                else if (suspends)
                        suspend(ctl_fd);
                else if (standbys)
                        stand_by(ctl_fd);
                else if (hibernates)
                        hibernate(ctl_fd);
                else if (resumes)
                        resumed(ctl_fd);

                if (powerchange) {
                        if (powerstatus)
                                do_etc_file(_PATH_APM_ETC_POWERUP);
                        else
                                do_etc_file(_PATH_APM_ETC_POWERDOWN);
                        powerchange = 0;
                }
        }
        error("kevent loop", NULL);

        return 1;
}

void
setperfpolicy(char *policy)
{
        int hw_perfpol_mib[] = { CTL_HW, HW_PERFPOLICY };
        int hw_perf_mib[] = { CTL_HW, HW_SETPERF };
        int new_perf = -1;

        if (strcmp(policy, "low") == 0) {
                policy = "manual";
                new_perf = 0;
        } else if (strcmp(policy, "high") == 0) {
                policy = "manual";
                new_perf = 100;
        }

        if (sysctl(hw_perfpol_mib, 2, NULL, NULL,
            policy, strlen(policy) + 1) == -1)
                logmsg(LOG_INFO, "cannot set hw.perfpolicy");

        if (new_perf == -1)
                return;

        if (sysctl(hw_perf_mib, 2, NULL, NULL,
            &new_perf, sizeof(new_perf)) == -1)
                logmsg(LOG_INFO, "cannot set hw.setperf");
}

void
do_etc_file(const char *file)
{
        pid_t pid;
        int status;
        const char *prog;

        /* If file doesn't exist, do nothing. */
        if (access(file, X_OK|R_OK)) {
                logmsg(LOG_DEBUG, "do_etc_file(): cannot access file %s", file);
                return;
        }

        prog = strrchr(file, '/');
        if (prog)
                prog++;
        else
                prog = file;

        pid = fork();
        switch (pid) {
        case -1:
                logmsg(LOG_ERR, "failed to fork(): %s", strerror(errno));
                return;
        case 0:
                /* We are the child. */
                execl(file, prog, (char *)NULL);
                logmsg(LOG_ERR, "failed to exec %s: %s", file, strerror(errno));
                _exit(1);
                /* NOTREACHED */
        default:
                /* We are the parent. */
                wait4(pid, &status, 0, 0);
                if (WIFEXITED(status))
                        logmsg(LOG_DEBUG, "%s exited with status %d", file,
                            WEXITSTATUS(status));
                else
                        logmsg(LOG_ERR, "%s exited abnormally.", file);
        }
}