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