LXR busybox/util-linux/acpid.c

   1/* vi: set sw=4 ts=4: */
   2/*
   3 * simple ACPI events listener
   4 *
   5 * Copyright (C) 2008 by Vladimir Dronnikov <dronnikov@gmail.com>
   6 *
   7 * Licensed under GPLv2, see file LICENSE in this source tree.
   8 */
   9//config:config ACPID
  10//config:       bool "acpid (9 kb)"
  11//config:       default y
  12//config:       select PLATFORM_LINUX
  13//config:       help
  14//config:       acpid listens to ACPI events coming either in textual form from
  15//config:       /proc/acpi/event (though it is marked deprecated it is still widely
  16//config:       used and _is_ a standard) or in binary form from specified evdevs
  17//config:       (just use /dev/input/event*).
  18//config:
  19//config:       It parses the event to retrieve ACTION and a possible PARAMETER.
  20//config:       It then spawns /etc/acpi/<ACTION>[/<PARAMETER>] either via run-parts
  21//config:       (if the resulting path is a directory) or directly as an executable.
  22//config:
  23//config:       N.B. acpid relies on run-parts so have the latter installed.
  24//config:
  25//config:config FEATURE_ACPID_COMPAT
  26//config:       bool "Accept and ignore redundant options"
  27//config:       default y
  28//config:       depends on ACPID
  29//config:       help
  30//config:       Accept and ignore compatibility options -g -m -s -S -v.
  31
  32//applet:IF_ACPID(APPLET(acpid, BB_DIR_SBIN, BB_SUID_DROP))
  33
  34//kbuild:lib-$(CONFIG_ACPID) += acpid.o
  35
  36//usage:#define acpid_trivial_usage
  37//usage:       "[-df] [-c CONFDIR] [-l LOGFILE] [-a ACTIONFILE] [-M MAPFILE] [-e PROC_EVENT_FILE] [-p PIDFILE]"
  38//usage:#define acpid_full_usage "\n\n"
  39//usage:       "Listen to ACPI events and spawn specific helpers on event arrival\n"
  40//usage:     "\n        -d      Log to stderr, not log file (implies -f)"
  41//usage:     "\n        -f      Run in foreground"
  42//usage:     "\n        -c DIR  Config directory [/etc/acpi]"
  43//usage:     "\n        -e FILE /proc event file [/proc/acpi/event]"
  44//usage:     "\n        -l FILE Log file [/var/log/acpid.log]"
  45//usage:     "\n        -p FILE Pid file [/var/run/acpid.pid]"
  46//usage:     "\n        -a FILE Action file [/etc/acpid.conf]"
  47//usage:     "\n        -M FILE Map file [/etc/acpi.map]"
  48//usage:        IF_FEATURE_ACPID_COMPAT(
  49//usage:     "\n\nAccept and ignore compatibility options -g -m -s -S -v"
  50//usage:        )
  51//usage:
  52//usage:#define acpid_example_usage
  53//usage:       "Without -e option, acpid uses all /dev/input/event* files\n"
  54//usage:       "# acpid\n"
  55//usage:       "# acpid -l /var/log/my-acpi-log\n"
  56//usage:       "# acpid -e /proc/acpi/event\n"
  57
  58#include "libbb.h"
  59#include <syslog.h>
  60#include <linux/input.h>
  61
  62#ifndef EV_SW
  63# define EV_SW         0x05
  64#endif
  65#ifndef EV_KEY
  66# define EV_KEY        0x01
  67#endif
  68#ifndef SW_LID
  69# define SW_LID        0x00
  70#endif
  71#ifndef SW_RFKILL_ALL
  72# define SW_RFKILL_ALL 0x03
  73#endif
  74#ifndef KEY_POWER
  75# define KEY_POWER      116     /* SC System Power Down */
  76#endif
  77#ifndef KEY_SLEEP
  78# define KEY_SLEEP      142     /* SC System Sleep */
  79#endif
  80
  81enum {
  82        OPT_c = (1 << 0),
  83        OPT_d = (1 << 1),
  84        OPT_e = (1 << 2),
  85        OPT_f = (1 << 3),
  86        OPT_l = (1 << 4),
  87        OPT_a = (1 << 5),
  88        OPT_M = (1 << 6),
  89        OPT_p = (1 << 7) * ENABLE_FEATURE_PIDFILE,
  90};
  91
  92struct acpi_event {
  93        const char *s_type;
  94        uint16_t n_type;
  95        const char *s_code;
  96        uint16_t n_code;
  97        uint32_t value;
  98        const char *desc;
  99};
 100
 101static const struct acpi_event f_evt_tab[] = {
 102        { "EV_KEY", 0x01, "KEY_POWER", 116, 1, "button/power PWRF 00000080" },
 103        { "EV_KEY", 0x01, "KEY_POWER", 116, 1, "button/power PWRB 00000080" },
 104        { "EV_SW", 0x05, "SW_LID", 0x00, 1, "button/lid LID0 00000080" },
 105};
 106
 107struct acpi_action {
 108        const char *key;
 109        const char *action;
 110};
 111
 112static const struct acpi_action f_act_tab[] = {
 113        { "PWRF", "PWRF/00000080" },
 114        { "LID0", "LID/00000080" },
 115};
 116
 117struct globals {
 118        struct acpi_action *act_tab;
 119        int n_act;
 120        struct acpi_event *evt_tab;
 121        int n_evt;
 122} FIX_ALIASING;
 123#define G (*ptr_to_globals)
 124#define act_tab         (G.act_tab)
 125#define n_act           (G.n_act  )
 126#define evt_tab         (G.evt_tab)
 127#define n_evt           (G.n_evt  )
 128#define INIT_G() do { \
 129        SET_PTR_TO_GLOBALS(xzalloc(sizeof(G))); \
 130} while (0)
 131
 132/*
 133 * acpid listens to ACPI events coming either in textual form
 134 * from /proc/acpi/event (though it is marked deprecated,
 135 * it is still widely used and _is_ a standard) or in binary form
 136 * from specified evdevs (just use /dev/input/event*).
 137 * It parses the event to retrieve ACTION and a possible PARAMETER.
 138 * It then spawns /etc/acpi/<ACTION>[/<PARAMETER>] either via run-parts
 139 * (if the resulting path is a directory) or directly.
 140 * If the resulting path does not exist it logs it via perror
 141 * and continues listening.
 142 */
 143
 144static void process_event(const char *event)
 145{
 146        struct stat st;
 147        char *handler = xasprintf("./%s", event);
 148        const char *args[] = { "run-parts", handler, NULL };
 149
 150        // log the event
 151        bb_error_msg("%s", event);
 152
 153        // spawn handler
 154        // N.B. run-parts would require scripts to have #!/bin/sh
 155        // handler is directory? -> use run-parts
 156        // handler is file? -> run it directly
 157        if (0 == stat(event, &st))
 158                spawn((char **)args + (0==(st.st_mode & S_IFDIR)));
 159        else
 160                bb_simple_perror_msg(event);
 161
 162        free(handler);
 163}
 164
 165static const char *find_action(struct input_event *ev, const char *buf)
 166{
 167        const char *action = NULL;
 168        int i;
 169
 170        // map event
 171        for (i = 0; i < n_evt; i++) {
 172                if (ev) {
 173                        if (ev->type == evt_tab[i].n_type && ev->code == evt_tab[i].n_code && ev->value == evt_tab[i].value) {
 174                                action = evt_tab[i].desc;
 175                                break;
 176                        }
 177                }
 178
 179                if (buf) {
 180                        if (is_prefixed_with(evt_tab[i].desc, buf)) {
 181                                action = evt_tab[i].desc;
 182                                break;
 183                        }
 184                }
 185        }
 186
 187        // get action
 188        if (action) {
 189                for (i = 0; i < n_act; i++) {
 190                        if (strstr(action, act_tab[i].key)) {
 191                                action = act_tab[i].action;
 192                                break;
 193                        }
 194                }
 195        }
 196
 197        return action;
 198}
 199
 200static void parse_conf_file(const char *filename)
 201{
 202        parser_t *parser;
 203        char *tokens[2];
 204
 205        parser = config_open2(filename, fopen_for_read);
 206
 207        if (parser) {
 208                while (config_read(parser, tokens, 2, 2, "# \t", PARSE_NORMAL)) {
 209                        act_tab = xrealloc_vector(act_tab, 1, n_act);
 210                        act_tab[n_act].key = xstrdup(tokens[0]);
 211                        act_tab[n_act].action = xstrdup(tokens[1]);
 212                        n_act++;
 213                }
 214                config_close(parser);
 215        } else {
 216                act_tab = (void*)f_act_tab;
 217                n_act = ARRAY_SIZE(f_act_tab);
 218        }
 219}
 220
 221static void parse_map_file(const char *filename)
 222{
 223        parser_t *parser;
 224        char *tokens[6];
 225
 226        parser = config_open2(filename, fopen_for_read);
 227
 228        if (parser) {
 229                while (config_read(parser, tokens, 6, 6, "# \t", PARSE_NORMAL)) {
 230                        evt_tab = xrealloc_vector(evt_tab, 1, n_evt);
 231                        evt_tab[n_evt].s_type = xstrdup(tokens[0]);
 232                        evt_tab[n_evt].n_type = xstrtou(tokens[1], 16);
 233                        evt_tab[n_evt].s_code = xstrdup(tokens[2]);
 234                        evt_tab[n_evt].n_code = xatou16(tokens[3]);
 235                        evt_tab[n_evt].value = xatoi_positive(tokens[4]);
 236                        evt_tab[n_evt].desc = xstrdup(tokens[5]);
 237                        n_evt++;
 238                }
 239                config_close(parser);
 240        } else {
 241                evt_tab = (void*)f_evt_tab;
 242                n_evt = ARRAY_SIZE(f_evt_tab);
 243        }
 244}
 245
 246/*
 247 * acpid [-c conf_dir] [-r conf_file ] [-a map_file ] [-l log_file] [-e proc_event_file]
 248 */
 249
 250int acpid_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 251int acpid_main(int argc UNUSED_PARAM, char **argv)
 252{
 253        int nfd;
 254        int opts;
 255        struct pollfd *pfd;
 256        const char *opt_dir = "/etc/acpi";
 257        const char *opt_input = "/dev/input/event";
 258        const char *opt_logfile = "/var/log/acpid.log";
 259        const char *opt_action = "/etc/acpid.conf";
 260        const char *opt_map = "/etc/acpi.map";
 261#if ENABLE_FEATURE_PIDFILE
 262        const char *opt_pidfile = CONFIG_PID_FILE_PATH "/acpid.pid";
 263#endif
 264
 265        INIT_G();
 266
 267        opts = getopt32(argv, "^"
 268                "c:de:fl:a:M:"
 269                IF_FEATURE_PIDFILE("p:")
 270                IF_FEATURE_ACPID_COMPAT("g:m:s:S:v")
 271                "\0"
 272                "df:e--e",
 273                &opt_dir, &opt_input, &opt_logfile, &opt_action, &opt_map
 274                IF_FEATURE_PIDFILE(, &opt_pidfile)
 275                IF_FEATURE_ACPID_COMPAT(, NULL, NULL, NULL, NULL)
 276        );
 277
 278        if (!(opts & OPT_f)) {
 279                /* No -f "Foreground", we go to background */
 280                bb_daemonize_or_rexec(DAEMON_CLOSE_EXTRA_FDS, argv);
 281        }
 282
 283        if (!(opts & OPT_d)) {
 284                /* No -d "Debug", we log to log file.
 285                 * This includes any output from children.
 286                 */
 287                xmove_fd(xopen(opt_logfile, O_WRONLY | O_CREAT | O_APPEND), STDOUT_FILENO);
 288                xdup2(STDOUT_FILENO, STDERR_FILENO);
 289                /* Also, acpid's messages (but not children) will go to syslog too */
 290                openlog(applet_name, LOG_PID, LOG_DAEMON);
 291                logmode = LOGMODE_SYSLOG | LOGMODE_STDIO;
 292        }
 293        /* else: -d "Debug", log is not redirected */
 294
 295        parse_conf_file(opt_action);
 296        parse_map_file(opt_map);
 297
 298        xchdir(opt_dir);
 299
 300        /* We spawn children but don't wait for them. Prevent zombies: */
 301        bb_signals((1 << SIGCHLD), SIG_IGN);
 302        // If you enable this, (1) explain why, (2)
 303        // make sure while(poll) loop below is still interruptible
 304        // by SIGTERM et al:
 305        //bb_signals(BB_FATAL_SIGS, record_signo);
 306
 307        pfd = NULL;
 308        nfd = 0;
 309        while (1) {
 310                int fd;
 311                char *dev_event;
 312
 313                dev_event = xasprintf((opts & OPT_e) ? "%s" : "%s%u", opt_input, nfd);
 314                fd = open(dev_event, O_RDONLY | O_NONBLOCK);
 315                if (fd < 0) {
 316                        if (nfd == 0)
 317                                bb_simple_perror_msg_and_die(dev_event);
 318                        break;
 319                }
 320                free(dev_event);
 321                pfd = xrealloc_vector(pfd, 1, nfd);
 322                pfd[nfd].fd = fd;
 323                pfd[nfd].events = POLLIN;
 324                nfd++;
 325        }
 326
 327        write_pidfile(opt_pidfile);
 328
 329        while (safe_poll(pfd, nfd, -1) > 0) {
 330                int i;
 331                for (i = 0; i < nfd; i++) {
 332                        const char *event;
 333
 334                        if (!(pfd[i].revents & POLLIN)) {
 335                                if (pfd[i].revents == 0)
 336                                        continue; /* this fd has nothing */
 337
 338                                /* Likely POLLERR, POLLHUP, POLLNVAL.
 339                                 * Do not listen on this fd anymore.
 340                                 */
 341                                close(pfd[i].fd);
 342                                nfd--;
 343                                for (; i < nfd; i++)
 344                                        pfd[i].fd = pfd[i + 1].fd;
 345                                break; /* do poll() again */
 346                        }
 347
 348                        event = NULL;
 349                        if (option_mask32 & OPT_e) {
 350                                char *buf;
 351                                int len;
 352
 353                                buf = xmalloc_reads(pfd[i].fd, NULL);
 354                                /* buf = "button/power PWRB 00000080 00000000" */
 355                                len = strlen(buf) - 9;
 356                                if (len >= 0)
 357                                        buf[len] = '\0';
 358                                event = find_action(NULL, buf);
 359                                free(buf);
 360                        } else {
 361                                struct input_event ev;
 362
 363                                if (sizeof(ev) != full_read(pfd[i].fd, &ev, sizeof(ev)))
 364                                        continue;
 365
 366                                if (ev.value != 1 && ev.value != 0)
 367                                        continue;
 368
 369                                event = find_action(&ev, NULL);
 370                        }
 371                        if (!event)
 372                                continue;
 373                        /* spawn event handler */
 374                        process_event(event);
 375                }
 376        }
 377
 378        if (ENABLE_FEATURE_CLEAN_UP) {
 379                while (nfd--)
 380                        close(pfd[nfd].fd);
 381                free(pfd);
 382        }
 383        remove_pidfile(opt_pidfile);
 384
 385        return EXIT_SUCCESS;
 386}
 387