source: MondoRescue/branches/3.2/mindi-busybox/util-linux/acpid.c@ 3232

/* vi: set sw=4 ts=4: */
/*
 * simple ACPI events listener
 *
 * Copyright (C) 2008 by Vladimir Dronnikov <dronnikov@gmail.com>
 *
 * Licensed under GPLv2, see file LICENSE in this source tree.
 */

//usage:#define acpid_trivial_usage
//usage:       "[-df] [-c CONFDIR] [-l LOGFILE] [-a ACTIONFILE] [-M MAPFILE] [-e PROC_EVENT_FILE] [-p PIDFILE]"
//usage:#define acpid_full_usage "\n\n"
//usage:       "Listen to ACPI events and spawn specific helpers on event arrival\n"
//usage:     "\n    -d  Log to stderr, not log file (implies -f)"
//usage:     "\n    -f  Run in foreground"
//usage:     "\n    -c DIR  Config directory [/etc/acpi]"
//usage:     "\n    -e FILE /proc event file [/proc/acpi/event]"
//usage:     "\n    -l FILE Log file [/var/log/acpid.log]"
//usage:     "\n    -p FILE Pid file [/var/run/acpid.pid]"
//usage:     "\n    -a FILE Action file [/etc/acpid.conf]"
//usage:     "\n    -M FILE Map file [/etc/acpi.map]"
//usage:    IF_FEATURE_ACPID_COMPAT(
//usage:     "\n\nAccept and ignore compatibility options -g -m -s -S -v"
//usage:    )
//usage:
//usage:#define acpid_example_usage
//usage:       "Without -e option, acpid uses all /dev/input/event* files\n"
//usage:       "# acpid\n"
//usage:       "# acpid -l /var/log/my-acpi-log\n"
//usage:       "# acpid -e /proc/acpi/event\n"

#include "libbb.h"
#include <syslog.h>
#include <linux/input.h>

#ifndef EV_SW
# define EV_SW         0x05
#endif
#ifndef EV_KEY
# define EV_KEY        0x01
#endif
#ifndef SW_LID
# define SW_LID        0x00
#endif
#ifndef SW_RFKILL_ALL
# define SW_RFKILL_ALL 0x03
#endif
#ifndef KEY_POWER
# define KEY_POWER      116     /* SC System Power Down */
#endif
#ifndef KEY_SLEEP
# define KEY_SLEEP      142     /* SC System Sleep */
#endif

enum {
    OPT_c = (1 << 0),
    OPT_d = (1 << 1),
    OPT_e = (1 << 2),
    OPT_f = (1 << 3),
    OPT_l = (1 << 4),
    OPT_a = (1 << 5),
    OPT_M = (1 << 6),
    OPT_p = (1 << 7) * ENABLE_FEATURE_PIDFILE,
};

struct acpi_event {
    const char *s_type;
    uint16_t n_type;
    const char *s_code;
    uint16_t n_code;
    uint32_t value;
    const char *desc;
};

static const struct acpi_event f_evt_tab[] = {
    { "EV_KEY", 0x01, "KEY_POWER", 116, 1, "button/power PWRF 00000080" },
    { "EV_KEY", 0x01, "KEY_POWER", 116, 1, "button/power PWRB 00000080" },
    { "EV_SW", 0x05, "SW_LID", 0x00, 1, "button/lid LID0 00000080" },
};

struct acpi_action {
    const char *key;
    const char *action;
};

static const struct acpi_action f_act_tab[] = {
    { "PWRF", "PWRF/00000080" },
    { "LID0", "LID/00000080" },
};

struct globals {
    struct acpi_action *act_tab;
    int n_act;
    struct acpi_event *evt_tab;
    int n_evt;
} FIX_ALIASING;
#define G (*ptr_to_globals)
#define act_tab         (G.act_tab)
#define n_act           (G.n_act  )
#define evt_tab         (G.evt_tab)
#define n_evt           (G.n_evt  )
#define INIT_G() do { \
    SET_PTR_TO_GLOBALS(xzalloc(sizeof(G))); \
} while (0)

/*
 * acpid listens to ACPI events coming either in textual form
 * from /proc/acpi/event (though it is marked deprecated,
 * it is still widely used and _is_ a standard) or in binary form
 * from specified evdevs (just use /dev/input/event*).
 * It parses the event to retrieve ACTION and a possible PARAMETER.
 * It then spawns /etc/acpi/<ACTION>[/<PARAMETER>] either via run-parts
 * (if the resulting path is a directory) or directly.
 * If the resulting path does not exist it logs it via perror
 * and continues listening.
 */

static void process_event(const char *event)
{
    struct stat st;
    char *handler = xasprintf("./%s", event);
    const char *args[] = { "run-parts", handler, NULL };

    // debug info
    if (option_mask32 & OPT_d) {
        bb_error_msg("%s", event);
    }

    // spawn handler
    // N.B. run-parts would require scripts to have #!/bin/sh
    // handler is directory? -> use run-parts
    // handler is file? -> run it directly
    if (0 == stat(event, &st))
        spawn((char **)args + (0==(st.st_mode & S_IFDIR)));
    else
        bb_simple_perror_msg(event);

    free(handler);
}

static const char *find_action(struct input_event *ev, const char *buf)
{
    const char *action = NULL;
    int i;

    // map event
    for (i = 0; i < n_evt; i++) {
        if (ev) {
            if (ev->type == evt_tab[i].n_type && ev->code == evt_tab[i].n_code && ev->value == evt_tab[i].value) {
                action = evt_tab[i].desc;
                break;
            }
        }

        if (buf) {
            if (strncmp(buf, evt_tab[i].desc, strlen(buf)) == 0) {
                action = evt_tab[i].desc;
                break;
            }
        }
    }

    // get action
    if (action) {
        for (i = 0; i < n_act; i++) {
            if (strstr(action, act_tab[i].key)) {
                action = act_tab[i].action;
                break;
            }
        }
    }

    return action;
}

static void parse_conf_file(const char *filename)
{
    parser_t *parser;
    char *tokens[2];

    parser = config_open2(filename, fopen_for_read);

    if (parser) {
        while (config_read(parser, tokens, 2, 2, "# \t", PARSE_NORMAL)) {
            act_tab = xrealloc_vector(act_tab, 1, n_act);
            act_tab[n_act].key = xstrdup(tokens[0]);
            act_tab[n_act].action = xstrdup(tokens[1]);
            n_act++;
        }
        config_close(parser);
    } else {
        act_tab = (void*)f_act_tab;
        n_act = ARRAY_SIZE(f_act_tab);
    }
}

static void parse_map_file(const char *filename)
{
    parser_t *parser;
    char *tokens[6];

    parser = config_open2(filename, fopen_for_read);

    if (parser) {
        while (config_read(parser, tokens, 6, 6, "# \t", PARSE_NORMAL)) {
            evt_tab = xrealloc_vector(evt_tab, 1, n_evt);
            evt_tab[n_evt].s_type = xstrdup(tokens[0]);
            evt_tab[n_evt].n_type = xstrtou(tokens[1], 16);
            evt_tab[n_evt].s_code = xstrdup(tokens[2]);
            evt_tab[n_evt].n_code = xatou16(tokens[3]);
            evt_tab[n_evt].value = xatoi_positive(tokens[4]);
            evt_tab[n_evt].desc = xstrdup(tokens[5]);
            n_evt++;
        }
        config_close(parser);
    } else {
        evt_tab = (void*)f_evt_tab;
        n_evt = ARRAY_SIZE(f_evt_tab);
    }
}

/*
 * acpid [-c conf_dir] [-r conf_file ] [-a map_file ] [-l log_file] [-e proc_event_file]
 */

int acpid_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int acpid_main(int argc UNUSED_PARAM, char **argv)
{
    int nfd;
    int opts;
    struct pollfd *pfd;
    const char *opt_dir = "/etc/acpi";
    const char *opt_input = "/dev/input/event";
    const char *opt_logfile = "/var/log/acpid.log";
    const char *opt_action = "/etc/acpid.conf";
    const char *opt_map = "/etc/acpi.map";
#if ENABLE_FEATURE_PIDFILE
    const char *opt_pidfile = CONFIG_PID_FILE_PATH "/acpid.pid";
#endif

    INIT_G();

    opt_complementary = "df:e--e";
    opts = getopt32(argv, "c:de:fl:a:M:" IF_FEATURE_PIDFILE("p:") IF_FEATURE_ACPID_COMPAT("g:m:s:S:v"),
        &opt_dir, &opt_input, &opt_logfile, &opt_action, &opt_map
        IF_FEATURE_PIDFILE(, &opt_pidfile)
        IF_FEATURE_ACPID_COMPAT(, NULL, NULL, NULL, NULL)
    );

    if (!(opts & OPT_f)) {
        /* No -f "Foreground", we go to background */
        bb_daemonize_or_rexec(DAEMON_CLOSE_EXTRA_FDS, argv);
    }

    if (!(opts & OPT_d)) {
        /* No -d "Debug", we log to log file.
         * This includes any output from children.
         */
        xmove_fd(xopen(opt_logfile, O_WRONLY | O_CREAT | O_TRUNC), STDOUT_FILENO);
        xdup2(STDOUT_FILENO, STDERR_FILENO);
        /* Also, acpid's messages (but not children) will go to syslog too */
        openlog(applet_name, LOG_PID, LOG_DAEMON);
        logmode = LOGMODE_SYSLOG | LOGMODE_STDIO;
    }
    /* else: -d "Debug", log is not redirected */

    parse_conf_file(opt_action);
    parse_map_file(opt_map);

    xchdir(opt_dir);

    /* We spawn children but don't wait for them. Prevent zombies: */
    bb_signals((1 << SIGCHLD), SIG_IGN);
    // If you enable this, (1) explain why, (2)
    // make sure while(poll) loop below is still interruptible
    // by SIGTERM et al:
    //bb_signals(BB_FATAL_SIGS, record_signo);

    pfd = NULL;
    nfd = 0;
    while (1) {
        int fd;
        char *dev_event;

        dev_event = xasprintf((opts & OPT_e) ? "%s" : "%s%u", opt_input, nfd);
        fd = open(dev_event, O_RDONLY | O_NONBLOCK);
        if (fd < 0) {
            if (nfd == 0)
                bb_simple_perror_msg_and_die(dev_event);
            break;
        }
        free(dev_event);
        pfd = xrealloc_vector(pfd, 1, nfd);
        pfd[nfd].fd = fd;
        pfd[nfd].events = POLLIN;
        nfd++;
    }

    write_pidfile(opt_pidfile);

    while (safe_poll(pfd, nfd, -1) > 0) {
        int i;
        for (i = 0; i < nfd; i++) {
            const char *event;

            if (!(pfd[i].revents & POLLIN)) {
                if (pfd[i].revents == 0)
                    continue; /* this fd has nothing */

                /* Likely POLLERR, POLLHUP, POLLNVAL.
                 * Do not listen on this fd anymore.
                 */
                close(pfd[i].fd);
                nfd--;
                for (; i < nfd; i++)
                    pfd[i].fd = pfd[i + 1].fd;
                break; /* do poll() again */
            }

            event = NULL;
            if (option_mask32 & OPT_e) {
                char *buf;
                int len;

                buf = xmalloc_reads(pfd[i].fd, NULL);
                /* buf = "button/power PWRB 00000080 00000000" */
                len = strlen(buf) - 9;
                if (len >= 0)
                    buf[len] = '\0';
                event = find_action(NULL, buf);
                free(buf);
            } else {
                struct input_event ev;

                if (sizeof(ev) != full_read(pfd[i].fd, &ev, sizeof(ev)))
                    continue;

                if (ev.value != 1 && ev.value != 0)
                    continue;

                event = find_action(&ev, NULL);
            }
            if (!event)
                continue;
            /* spawn event handler */
            process_event(event);
        }
    }

    if (ENABLE_FEATURE_CLEAN_UP) {
        while (nfd--)
            close(pfd[nfd].fd);
        free(pfd);
    }
    remove_pidfile(opt_pidfile);

    return EXIT_SUCCESS;
}