/*      $NetBSD: apmd.c,v 1.32 2011/11/25 12:51:27 joerg Exp $  */

/*-
 * Copyright (c) 1996, 2000 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by John Kohl.
 *
 * 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
 */

#include <stdio.h>
#include <errno.h>
#include <syslog.h>
#include <fcntl.h>
#include <unistd.h>
#include <util.h>
#include <stdlib.h>
#include <string.h>
#include <signal.h>
#include <sys/types.h>
#include <pwd.h>
#include <grp.h>
#include <sys/stat.h>
#include <sys/ioctl.h>
#include <sys/time.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <sys/wait.h>
#include <poll.h>
#include <machine/apmvar.h>
#include <err.h>
#include "pathnames.h"
#include "apm-proto.h"

#define TRUE 1
#define FALSE 0

#define POWER_STATUS_ACON       0x1
#define POWER_STATUS_LOWBATTNOW 0x2

static const char apmdev[] = _PATH_APM_CTLDEV;
static const char sockfile[] = _PATH_APM_SOCKET;

static int debug = 0;
static int verbose = 0;

__dead static void usage (void);
static int power_status (int fd, int force, struct apm_power_info *pinfo);
static int bind_socket (const char *sn, mode_t mode, uid_t uid, gid_t gid);
static enum apm_state handle_client(int sock_fd, int ctl_fd);
static void suspend(int ctl_fd);
static void stand_by(int ctl_fd);
static void resume(int ctl_fd);
__dead static void sigexit(int signo);
static void make_noise(int howmany);
static void do_etc_file(const char *file);
static void do_ac_state(int state);

static void
sigexit(int signo)
{
    exit(1);
}

static void
usage(void)
{
    fprintf(stderr,"usage: %s [-adlqsv] [-t seconds] [-S sockname]\n\t[-m sockmode] [-o sockowner:sockgroup] [-f devname]\n", getprogname());
    exit(1);
}


static 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;
    int lowbattnow = 0;

    memset(&bstate, 0, sizeof(bstate));
    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 != last.battery_state  &&
            bstate.battery_state == APM_BATT_LOW)
                lowbattnow = 1;
        if (force || 
            bstate.ac_state != last.ac_state ||
            bstate.battery_state != last.battery_state ||
            (bstate.minutes_left && bstate.minutes_left < 15) ||
            abs(bstate.battery_life - last.battery_life) > 20) {
            if (verbose) {
                if (bstate.minutes_left)
                    syslog(LOG_NOTICE,
                           "battery status: %s. external power status: %s. "
                           "estimated battery life %d%% (%d minutes)",
                           battstate(bstate.battery_state),
                           ac_state(bstate.ac_state), bstate.battery_life,
                           bstate.minutes_left);
                else
                    syslog(LOG_NOTICE,
                           "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
        syslog(LOG_ERR, "cannot fetch power status: %m");
    return ((acon?POWER_STATUS_ACON:0) |
        (lowbattnow?POWER_STATUS_LOWBATTNOW:0));
}

static char *socketname;

static void sockunlink(void);

static void
sockunlink(void)
{
    if (socketname)
        (void) remove(socketname);
}

static int
bind_socket(const char *sockname, mode_t mode, uid_t uid, gid_t gid)
{
    int sock;
    struct sockaddr_un s_un;

    sock = socket(AF_LOCAL, SOCK_STREAM, 0);
    if (sock == -1)
        err(1, "cannot create local socket");

    s_un.sun_family = AF_LOCAL;
    strncpy(s_un.sun_path, sockname, sizeof(s_un.sun_path));
    s_un.sun_len = SUN_LEN(&s_un);
    /* remove it if present, we're moving in */
    (void) remove(sockname);
    if (bind(sock, (struct sockaddr *)&s_un, s_un.sun_len) == -1)
        err(1, "cannot create APM socket");
    if (chmod(sockname, mode) == -1 || chown(sockname, uid, gid) == -1)
        err(1, "cannot set socket mode/owner/group to %o/%d/%d",
            mode, uid, gid);
    listen(sock, 1);
    socketname = strdup(sockname);
    atexit(sockunlink);
    return sock;
}

static enum apm_state
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 = sizeof(from);
    struct apm_command cmd;
    struct apm_reply reply;

    cli_fd = accept(sock_fd, (struct sockaddr *)&from, &fromlen);
    if (cli_fd == -1) {
        syslog(LOG_INFO, "client accept failure: %m");
        return NORMAL;
    }
    if (recv(cli_fd, &cmd, sizeof(cmd), 0) != sizeof(cmd)) {
        (void) close(cli_fd);
        syslog(LOG_INFO, "client size botch");
        return NORMAL;
    }
    if (cmd.vno != APMD_VNO) {
        close(cli_fd);                  /* terminate client */
        /* no error message, just drop it. */
        return NORMAL;
    }
    power_status(ctl_fd, 0, &reply.batterystate);
    switch (cmd.action) {
    default:
        reply.newstate = NORMAL;
        break;
    case SUSPEND:
        reply.newstate = SUSPENDING;
        break;
    case STANDBY:
        reply.newstate = STANDING_BY;
        break;
    }   
    reply.vno = APMD_VNO;
    if (send(cli_fd, &reply, sizeof(reply), 0) != sizeof(reply)) {
        syslog(LOG_INFO, "client reply botch");
    }
    close(cli_fd);
    return reply.newstate;
}

static int speaker_ok = TRUE;

static void
make_noise(int howmany)
{
    int spkrfd;
    int trycnt;

    if (!speaker_ok)            /* don't bother after sticky errors */
        return;

    for (trycnt = 0; trycnt < 3; trycnt++) {
        spkrfd = open(_PATH_DEV_SPEAKER, O_WRONLY);
        if (spkrfd == -1) {
            switch (errno) {
            case EBUSY:
                usleep(500000);
                errno = EBUSY;
                continue;
            case ENOENT:
            case ENODEV:
            case ENXIO:
            case EPERM:
            case EACCES:
                syslog(LOG_INFO,
                       "speaker device " _PATH_DEV_SPEAKER " unavailable: %m");
                speaker_ok = FALSE;
                return;
            }
        } else
            break;
    }
    if (spkrfd == -1) {
        syslog(LOG_WARNING, "cannot open " _PATH_DEV_SPEAKER ": %m");
        return;
    }
    syslog(LOG_DEBUG, "sending %d tones to speaker\n", howmany);
    write (spkrfd, "o4cc", 2 + howmany);
    close(spkrfd);
    return;
}


static void
suspend(int ctl_fd)
{
    do_etc_file(_PATH_APM_ETC_SUSPEND);
    sync();
    make_noise(2);
    sync();
    sync();
    sleep(1);
    ioctl(ctl_fd, APM_IOC_SUSPEND, 0);
}

static void
stand_by(int ctl_fd)
{
    do_etc_file(_PATH_APM_ETC_STANDBY);
    sync();
    make_noise(1);
    sync();
    sync();
    sleep(1);
    ioctl(ctl_fd, APM_IOC_STANDBY, 0);
}

#define TIMO (10*60)                    /* 10 minutes */

static void
resume(int ctl_fd)
{
    do_etc_file(_PATH_APM_ETC_RESUME);
}

int
main(int argc, char *argv[])
{
    const char *fname = apmdev;
    int ctl_fd, sock_fd, ch, ready;
    int statonly = 0;
    struct pollfd set[2];
    struct apm_event_info apmevent;
    int suspends, standbys, resumes;
    int ac_is_off;
    int noacsleep = 0;
    int lowbattsleep = 0;
    mode_t mode = 0660;
    unsigned long timeout = TIMO;
    const char *sockname = sockfile;
    char *user, *group;
    char *scratch;
    uid_t uid = 2; /* operator */
    gid_t gid = 5; /* operator */
    struct passwd *pw;
    struct group *gr;

    while ((ch = getopt(argc, argv, "adlqsvf:t:S:m:o:")) != -1)
        switch(ch) {
        case 'q':
            speaker_ok = FALSE;
            break;
        case 'a':
            noacsleep = 1;
            break;
        case 'l':
            lowbattsleep = 1;
            break;
        case 'd':
            debug = 1;
            break;
        case 'v':
            verbose = 1;
            break;
        case 'f':
            fname = optarg;
            break;
        case 'S':
            sockname = optarg;
            break;
        case 't':
            timeout = strtoul(optarg, 0, 0);
            if (timeout == 0)
                usage();
            break;
        case 'm':
            mode = strtoul(optarg, 0, 8);
            if (mode == 0)
                usage();
            break;
        case 'o':
            /* (user):(group) */
            user = optarg;
            group = strchr(user, ':');
            if (group)
                *group++ = '\0';
            if (*user) {
                uid = strtoul(user, &scratch, 0);
                if (*scratch != '\0') {
                    pw = getpwnam(user);
                    if (pw)
                        uid = pw->pw_uid;
                    else
                        errx(1, "user name `%s' unknown", user);
                }
            }
            if (group && *group) {
                gid = strtoul(group, &scratch, 0);
                if (*scratch != '\0') {
                    gr = getgrnam(group);
                    if (gr)
                        gid = gr->gr_gid;
                    else
                        errx(1, "group name `%s' unknown", group);
                }
            }
            break;
        case 's':                       /* status only */
            statonly = 1;
            break;
        case '?':

        default:
            usage();
        }
    argc -= optind;
    argv += optind;
    if (debug) {
        openlog("apmd", 0, LOG_LOCAL1);
    } else {
        daemon(0, 0);
        openlog("apmd", 0, LOG_DAEMON);
        setlogmask(LOG_UPTO(LOG_NOTICE));
        pidfile(NULL);
    }
    if ((ctl_fd = open(fname, O_RDWR)) == -1) {
        syslog(LOG_ERR, "cannot open device file `%s'", fname);
        exit(1);
    } 

    if (statonly) {
        power_status(ctl_fd, 1, 0);
        exit(0);
    } else {
        struct apm_power_info pinfo;
        power_status(ctl_fd, 1, &pinfo);
        do_ac_state(pinfo.ac_state);
        ac_is_off = (pinfo.ac_state == APM_AC_OFF);
    }

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


    sock_fd = bind_socket(sockname, mode, uid, gid);

    set[0].fd = ctl_fd;
    set[0].events = POLLIN;
    set[1].fd = sock_fd;
    set[1].events = POLLIN;

    
    for (errno = 0;
         (ready = poll(set, 2, timeout * 1000)) >= 0 || errno == EINTR;
         errno = 0) {
        if (errno == EINTR)
            continue;
        if (ready == 0) {
                int status;
                /* wakeup for timeout: take status */
                status = power_status(ctl_fd, 0, 0);
                if (lowbattsleep && status&POWER_STATUS_LOWBATTNOW) {
                        if (noacsleep && status&POWER_STATUS_ACON) {
                                if (debug)
                                        syslog(LOG_DEBUG,
                                            "not sleeping because "
                                            "AC is connected");
                        } else
                                suspend(ctl_fd);
                }
        }
        if (set[0].revents & POLLIN) {
            suspends = standbys = resumes = 0;
            while (ioctl(ctl_fd, APM_IOC_NEXTEVENT, &apmevent) == 0) {
                if (debug)
                    syslog(LOG_DEBUG, "apmevent %04x index %d", apmevent.type,
                           apmevent.index);
                switch (apmevent.type) {
                case APM_SUSPEND_REQ:
                case APM_USER_SUSPEND_REQ:
                case APM_CRIT_SUSPEND_REQ:
                    suspends++;
                    break;
                case APM_BATTERY_LOW:
                    if (lowbattsleep)
                        suspends++;
                    break;
                case APM_USER_STANDBY_REQ:
                case APM_STANDBY_REQ:
                    standbys++;
                    break;
#if 0
                case APM_CANCEL:
                    suspends = standbys = 0;
                    break;
#endif
                case APM_NORMAL_RESUME:
                case APM_CRIT_RESUME:
                case APM_SYS_STANDBY_RESUME:
                    resumes++;
                    break;
                case APM_POWER_CHANGE:
                {
                    struct apm_power_info pinfo;
                    power_status(ctl_fd, 0, &pinfo);
                    /* power status can change without ac status changing */
                    if (ac_is_off != (pinfo.ac_state == APM_AC_OFF)) {
                        do_ac_state(pinfo.ac_state);
                        ac_is_off = (pinfo.ac_state == APM_AC_OFF);
                    }
                    break;
                }
                default:
                    break;
                }
            }
            if ((standbys || suspends) && noacsleep &&
                (power_status(ctl_fd, 0, 0) & POWER_STATUS_ACON)) {
                if (debug)
                    syslog(LOG_DEBUG, "not sleeping because AC is connected");
            } else if (suspends) {
                suspend(ctl_fd);
            } else if (standbys) {
                stand_by(ctl_fd);
            } else if (resumes) {
                resume(ctl_fd);
                if (verbose)
                    syslog(LOG_NOTICE, "system resumed from APM sleep");
            }
            ready--;
        }
        if (ready == 0)
            continue;
        if (set[1].revents & POLLIN) {
            switch (handle_client(sock_fd, ctl_fd)) {
            case NORMAL:
                break;
            case SUSPENDING:
                suspend(ctl_fd);
                break;
            case STANDING_BY:
                stand_by(ctl_fd);
                break;
            }
        }
    }
    syslog(LOG_ERR, "poll failed: %m");
    exit(1);
}

static 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)) {
        if (debug)
            syslog(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:
        syslog(LOG_ERR, "failed to fork(): %m");
        return;
    case 0:
        /* We are the child. */
        if (execl(file, prog, NULL) == -1)
                syslog(LOG_ERR, "could not execute \"%s\": %m", file);
        _exit(1);
        /* NOTREACHED */
    default:
        /* We are the parent. */
        wait4(pid, &status, 0, 0);
        if (WIFEXITED(status)) {
            if (debug)
                syslog(LOG_DEBUG, "%s exited with status %d", file,
                       WEXITSTATUS(status));
        } else
            syslog(LOG_ERR, "%s exited abnormally.", file);
        break;
    }
}

static void
do_ac_state(int state)
{
        switch (state) {
        case APM_AC_OFF:
                do_etc_file(_PATH_APM_ETC_BATTERY);
                break;
        case APM_AC_ON:
        case APM_AC_BACKUP:
                do_etc_file(_PATH_APM_ETC_LINE);
                break;
        default:
                /* Silently ignore */ ;
        }
}