release/src/router/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
  55 enum {
  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
  66 struct 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
  75 static 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
  81 struct acpi_action {
  82         const char *key;
  83         const char *action;
  84 };
  85
  86 static const struct acpi_action f_act_tab[] = {
  87         { "PWRF", "PWRF/00000080" },
  88         { "LID0", "LID/00000080" },
  89 };
  90
  91 struct 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
 118 static 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         // log the event
 125         bb_error_msg("%s", event);
 126
 127         // spawn handler
 128         // N.B. run-parts would require scripts to have #!/bin/sh
 129         // handler is directory? -> use run-parts
 130         // handler is file? -> run it directly
 131         if (0 == stat(event, &st))
 132                 spawn((char **)args + (0==(st.st_mode & S_IFDIR)));
 133         else
 134                 bb_simple_perror_msg(event);
 135
 136         free(handler);
 137 }
 138
 139 static const char *find_action(struct input_event *ev, const char *buf)
 140 {
 141         const char *action = NULL;
 142         int i;
 143
 144         // map event
 145         for (i = 0; i < n_evt; i++) {
 146                 if (ev) {
 147                         if (ev->type == evt_tab[i].n_type && ev->code == evt_tab[i].n_code && ev->value == evt_tab[i].value) {
 148                                 action = evt_tab[i].desc;
 149                                 break;
 150                         }
 151                 }
 152
 153                 if (buf) {
 154                         if (is_prefixed_with(evt_tab[i].desc, buf)) {
 155                                 action = evt_tab[i].desc;
 156                                 break;
 157                         }
 158                 }
 159         }
 160
 161         // get action
 162         if (action) {
 163                 for (i = 0; i < n_act; i++) {
 164                         if (strstr(action, act_tab[i].key)) {
 165                                 action = act_tab[i].action;
 166                                 break;
 167                         }
 168                 }
 169         }
 170
 171         return action;
 172 }
 173
 174 static void parse_conf_file(const char *filename)
 175 {
 176         parser_t *parser;
 177         char *tokens[2];
 178
 179         parser = config_open2(filename, fopen_for_read);
 180
 181         if (parser) {
 182                 while (config_read(parser, tokens, 2, 2, "# \t", PARSE_NORMAL)) {
 183                         act_tab = xrealloc_vector(act_tab, 1, n_act);
 184                         act_tab[n_act].key = xstrdup(tokens[0]);
 185                         act_tab[n_act].action = xstrdup(tokens[1]);
 186                         n_act++;
 187                 }
 188                 config_close(parser);
 189         } else {
 190                 act_tab = (void*)f_act_tab;
 191                 n_act = ARRAY_SIZE(f_act_tab);
 192         }
 193 }
 194
 195 static void parse_map_file(const char *filename)
 196 {
 197         parser_t *parser;
 198         char *tokens[6];
 199
 200         parser = config_open2(filename, fopen_for_read);
 201
 202         if (parser) {
 203                 while (config_read(parser, tokens, 6, 6, "# \t", PARSE_NORMAL)) {
 204                         evt_tab = xrealloc_vector(evt_tab, 1, n_evt);
 205                         evt_tab[n_evt].s_type = xstrdup(tokens[0]);
 206                         evt_tab[n_evt].n_type = xstrtou(tokens[1], 16);
 207                         evt_tab[n_evt].s_code = xstrdup(tokens[2]);
 208                         evt_tab[n_evt].n_code = xatou16(tokens[3]);
 209                         evt_tab[n_evt].value = xatoi_positive(tokens[4]);
 210                         evt_tab[n_evt].desc = xstrdup(tokens[5]);
 211                         n_evt++;
 212                 }
 213                 config_close(parser);
 214         } else {
 215                 evt_tab = (void*)f_evt_tab;
 216                 n_evt = ARRAY_SIZE(f_evt_tab);
 217         }
 218 }
 219
 220 /*
 221  * acpid [-c conf_dir] [-r conf_file ] [-a map_file ] [-l log_file] [-e proc_event_file]
 222  */
 223
 224 int acpid_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 225 int acpid_main(int argc UNUSED_PARAM, char **argv)
 226 {
 227         int nfd;
 228         int opts;
 229         struct pollfd *pfd;
 230         const char *opt_dir = "/etc/acpi";
 231         const char *opt_input = "/dev/input/event";
 232         const char *opt_logfile = "/var/log/acpid.log";
 233         const char *opt_action = "/etc/acpid.conf";
 234         const char *opt_map = "/etc/acpi.map";
 235 #if ENABLE_FEATURE_PIDFILE
 236         const char *opt_pidfile = CONFIG_PID_FILE_PATH "/acpid.pid";
 237 #endif
 238
 239         INIT_G();
 240
 241         opt_complementary = "df:e--e";
 242         opts = getopt32(argv, "c:de:fl:a:M:" IF_FEATURE_PIDFILE("p:") IF_FEATURE_ACPID_COMPAT("g:m:s:S:v"),
 243                 &opt_dir, &opt_input, &opt_logfile, &opt_action, &opt_map
 244                 IF_FEATURE_PIDFILE(, &opt_pidfile)
 245                 IF_FEATURE_ACPID_COMPAT(, NULL, NULL, NULL, NULL)
 246         );
 247
 248         if (!(opts & OPT_f)) {
 249                 /* No -f "Foreground", we go to background */
 250                 bb_daemonize_or_rexec(DAEMON_CLOSE_EXTRA_FDS, argv);
 251         }
 252
 253         if (!(opts & OPT_d)) {
 254                 /* No -d "Debug", we log to log file.
 255                  * This includes any output from children.
 256                  */
 257                 xmove_fd(xopen(opt_logfile, O_WRONLY | O_CREAT | O_APPEND), STDOUT_FILENO);
 258                 xdup2(STDOUT_FILENO, STDERR_FILENO);
 259                 /* Also, acpid's messages (but not children) will go to syslog too */
 260                 openlog(applet_name, LOG_PID, LOG_DAEMON);
 261                 logmode = LOGMODE_SYSLOG | LOGMODE_STDIO;
 262         }
 263         /* else: -d "Debug", log is not redirected */
 264
 265         parse_conf_file(opt_action);
 266         parse_map_file(opt_map);
 267
 268         xchdir(opt_dir);
 269
 270         /* We spawn children but don't wait for them. Prevent zombies: */
 271         bb_signals((1 << SIGCHLD), SIG_IGN);
 272         // If you enable this, (1) explain why, (2)
 273         // make sure while(poll) loop below is still interruptible
 274         // by SIGTERM et al:
 275         //bb_signals(BB_FATAL_SIGS, record_signo);
 276
 277         pfd = NULL;
 278         nfd = 0;
 279         while (1) {
 280                 int fd;
 281                 char *dev_event;
 282
 283                 dev_event = xasprintf((opts & OPT_e) ? "%s" : "%s%u", opt_input, nfd);
 284                 fd = open(dev_event, O_RDONLY | O_NONBLOCK);
 285                 if (fd < 0) {
 286                         if (nfd == 0)
 287                                 bb_simple_perror_msg_and_die(dev_event);
 288                         break;
 289                 }
 290                 free(dev_event);
 291                 pfd = xrealloc_vector(pfd, 1, nfd);
 292                 pfd[nfd].fd = fd;
 293                 pfd[nfd].events = POLLIN;
 294                 nfd++;
 295         }
 296
 297         write_pidfile(opt_pidfile);
 298
 299         while (safe_poll(pfd, nfd, -1) > 0) {
 300                 int i;
 301                 for (i = 0; i < nfd; i++) {
 302                         const char *event;
 303
 304                         if (!(pfd[i].revents & POLLIN)) {
 305                                 if (pfd[i].revents == 0)
 306                                         continue; /* this fd has nothing */
 307
 308                                 /* Likely POLLERR, POLLHUP, POLLNVAL.
 309                                  * Do not listen on this fd anymore.
 310                                  */
 311                                 close(pfd[i].fd);
 312                                 nfd--;
 313                                 for (; i < nfd; i++)
 314                                         pfd[i].fd = pfd[i + 1].fd;
 315                                 break; /* do poll() again */
 316                         }
 317
 318                         event = NULL;
 319                         if (option_mask32 & OPT_e) {
 320                                 char *buf;
 321                                 int len;
 322
 323                                 buf = xmalloc_reads(pfd[i].fd, NULL);
 324                                 /* buf = "button/power PWRB 00000080 00000000" */
 325                                 len = strlen(buf) - 9;
 326                                 if (len >= 0)
 327                                         buf[len] = '\0';
 328                                 event = find_action(NULL, buf);
 329                                 free(buf);
 330                         } else {
 331                                 struct input_event ev;
 332
 333                                 if (sizeof(ev) != full_read(pfd[i].fd, &ev, sizeof(ev)))
 334                                         continue;
 335
 336                                 if (ev.value != 1 && ev.value != 0)
 337                                         continue;
 338
 339                                 event = find_action(&ev, NULL);
 340                         }
 341                         if (!event)
 342                                 continue;
 343                         /* spawn event handler */
 344                         process_event(event);
 345                 }
 346         }
 347
 348         if (ENABLE_FEATURE_CLEAN_UP) {
 349                 while (nfd--)
 350                         close(pfd[nfd].fd);
 351                 free(pfd);
 352         }
 353         remove_pidfile(opt_pidfile);
 354
 355         return EXIT_SUCCESS;
 356 }