slstatus.c

   1 /* See LICENSE file for copyright and license details. */
   2
   3 #include <alsa/asoundlib.h>
   4 #include <err.h>
   5 #include <fcntl.h>
   6 #include <ifaddrs.h>
   7 #include <limits.h>
   8 #include <linux/wireless.h>
   9 #include <locale.h>
  10 #include <netdb.h>
  11 #include <pwd.h>
  12 #include <signal.h>
  13 #include <stdarg.h>
  14 #include <stdio.h>
  15 #include <stdlib.h>
  16 #include <string.h>
  17 #include <sys/ioctl.h>
  18 #include <sys/stat.h>
  19 #include <sys/statvfs.h>
  20 #include <sys/socket.h>
  21 #include <sys/sysinfo.h>
  22 #include <sys/types.h>
  23 #include <sys/utsname.h>
  24 #include <time.h>
  25 #include <unistd.h>
  26 #include <X11/Xlib.h>
  27
  28 #undef strlcat
  29 #undef strlcpy
  30
  31 #include "extern/arg.h"
  32 #include "extern/strlcat.h"
  33 #include "extern/concat.h"
  34
  35 struct arg {
  36         char *(*func)();
  37         const char *fmt;
  38         const char *args;
  39 };
  40
  41 static char *smprintf(const char *fmt, ...);
  42 static char *battery_perc(const char *bat);
  43 static char *battery_state(const char *bat);
  44 static char *cpu_perc(void);
  45 static char *datetime(const char *fmt);
  46 static char *disk_free(const char *mnt);
  47 static char *disk_perc(const char *mnt);
  48 static char *disk_total(const char *mnt);
  49 static char *disk_used(const char *mnt);
  50 static char *entropy(void);
  51 static char *gid(void);
  52 static char *hostname(void);
  53 static char *ip(const char *iface);
  54 static char *kernel_release(void);
  55 static char *load_avg(void);
  56 static char *ram_free(void);
  57 static char *ram_perc(void);
  58 static char *ram_used(void);
  59 static char *ram_total(void);
  60 static char *run_command(const char *cmd);
  61 static char *swap_free(void);
  62 static char *swap_perc(void);
  63 static char *swap_used(void);
  64 static char *swap_total(void);
  65 static char *temp(const char *file);
  66 static char *uid(void);
  67 static char *uptime(void);
  68 static char *username(void);
  69 static char *vol_perc(const char *card);
  70 static char *wifi_perc(const char *iface);
  71 static char *wifi_essid(const char *iface);
  72 static void sighandler(const int signo);
  73 static void usage(int);
  74
  75 char *argv0;
  76 char concat[];
  77 static unsigned short int delay = 0;
  78 static unsigned short int done;
  79 static unsigned short int dflag, oflag;
  80 static Display *dpy;
  81
  82 #include "config.h"
  83
  84 static char *
  85 smprintf(const char *fmt, ...)
  86 {
  87         va_list ap;
  88         char *ret;
  89         int len;
  90
  91         va_start(ap, fmt);
  92         len = vsnprintf(NULL, 0, fmt, ap);
  93         va_end(ap);
  94
  95         ret = malloc(++len);
  96         if (ret == NULL) {
  97                 err(1, "malloc");
  98         }
  99
 100         va_start(ap, fmt);
 101         vsnprintf(ret, len, fmt, ap);
 102         va_end(ap);
 103
 104         return ret;
 105 }
 106
 107 static char *
 108 battery_perc(const char *bat)
 109 {
 110         int perc;
 111         FILE *fp;
 112
 113         ccat(3, "/sys/class/power_supply/", bat, "/capacity");
 114         fp = fopen(concat, "r");
 115         if (fp == NULL) {
 116                 warn("Failed to open file %s", concat);
 117                 return smprintf("%s", UNKNOWN_STR);
 118         }
 119         fscanf(fp, "%i", &perc);
 120         fclose(fp);
 121
 122         return smprintf("%d%%", perc);
 123 }
 124
 125 static char *
 126 battery_state(const char *bat)
 127 {
 128         char state[12];
 129         FILE *fp;
 130
 131         ccat(3, "/sys/class/power_supply/", bat, "/status");
 132         fp = fopen(concat, "r");
 133         if (fp == NULL) {
 134                 warn("Failed to open file %s", concat);
 135                 return smprintf("%s", UNKNOWN_STR);
 136         }
 137         fscanf(fp, "%12s", state);
 138         fclose(fp);
 139
 140         if (strcmp(state, "Charging") == 0) {
 141                 return smprintf("+");
 142         } else if (strcmp(state, "Discharging") == 0) {
 143                 return smprintf("-");
 144         } else if (strcmp(state, "Full") == 0) {
 145                 return smprintf("=");
 146         } else {
 147                 return smprintf("?");
 148         }
 149 }
 150
 151 static char *
 152 cpu_perc(void)
 153 {
 154         int perc;
 155         long double a[4], b[4];
 156         FILE *fp;
 157
 158         fp = fopen("/proc/stat", "r");
 159         if (fp == NULL) {
 160                 warn("Failed to open file /proc/stat");
 161                 return smprintf("%s", UNKNOWN_STR);
 162         }
 163         fscanf(fp, "%*s %Lf %Lf %Lf %Lf", &a[0], &a[1], &a[2], &a[3]);
 164         fclose(fp);
 165
 166         delay++;
 167         sleep(delay);
 168
 169         fp = fopen("/proc/stat", "r");
 170         if (fp == NULL) {
 171                 warn("Failed to open file /proc/stat");
 172                 return smprintf("%s", UNKNOWN_STR);
 173         }
 174         fscanf(fp, "%*s %Lf %Lf %Lf %Lf", &b[0], &b[1], &b[2], &b[3]);
 175         fclose(fp);
 176
 177         perc = 100 * ((b[0]+b[1]+b[2]) - (a[0]+a[1]+a[2])) / ((b[0]+b[1]+b[2]+b[3]) - (a[0]+a[1]+a[2]+a[3]));
 178         return smprintf("%d%%", perc);
 179 }
 180
 181 static char *
 182 datetime(const char *fmt)
 183 {
 184         time_t t;
 185         char str[80];
 186
 187         t = time(NULL);
 188         if (strftime(str, sizeof(str), fmt, localtime(&t)) == 0) {
 189                 return smprintf("%s", UNKNOWN_STR);
 190         }
 191
 192         return smprintf("%s", str);
 193 }
 194
 195 static char *
 196 disk_free(const char *mnt)
 197 {
 198         struct statvfs fs;
 199
 200         if (statvfs(mnt, &fs) < 0) {
 201                 warn("Failed to get filesystem info");
 202                 return smprintf("%s", UNKNOWN_STR);
 203         }
 204
 205         return smprintf("%f", (float)fs.f_bsize * (float)fs.f_bfree / 1024 / 1024 / 1024);
 206 }
 207
 208 static char *
 209 disk_perc(const char *mnt)
 210 {
 211         int perc;
 212         struct statvfs fs;
 213
 214         if (statvfs(mnt, &fs) < 0) {
 215                 warn("Failed to get filesystem info");
 216                 return smprintf("%s", UNKNOWN_STR);
 217         }
 218
 219         perc = 100 * (1.0f - ((float)fs.f_bfree / (float)fs.f_blocks));
 220
 221         return smprintf("%d%%", perc);
 222 }
 223
 224 static char *
 225 disk_total(const char *mnt)
 226 {
 227         struct statvfs fs;
 228
 229         if (statvfs(mnt, &fs) < 0) {
 230                 warn("Failed to get filesystem info");
 231                 return smprintf("%s", UNKNOWN_STR);
 232         }
 233
 234         return smprintf("%f", (float)fs.f_bsize * (float)fs.f_blocks / 1024 / 1024 / 1024);
 235 }
 236
 237 static char *
 238 disk_used(const char *mnt)
 239 {
 240         struct statvfs fs;
 241
 242         if (statvfs(mnt, &fs) < 0) {
 243                 warn("Failed to get filesystem info");
 244                 return smprintf("%s", UNKNOWN_STR);
 245         }
 246
 247         return smprintf("%f", (float)fs.f_bsize * ((float)fs.f_blocks - (float)fs.f_bfree) / 1024 / 1024 / 1024);
 248 }
 249
 250 static char *
 251 entropy(void)
 252 {
 253         int num;
 254         FILE *fp;
 255
 256         fp= fopen("/proc/sys/kernel/random/entropy_avail", "r");
 257         if (fp == NULL) {
 258                 warn("Failed to open file /proc/sys/kernel/random/entropy_avail");
 259                 return smprintf("%s", UNKNOWN_STR);
 260         }
 261         fscanf(fp, "%d", &num);
 262         fclose(fp);
 263
 264         return smprintf("%d", num);
 265 }
 266
 267 static char *
 268 gid(void)
 269 {
 270         return smprintf("%d", getgid());
 271 }
 272
 273 static char *
 274 hostname(void)
 275 {
 276         char buf[HOST_NAME_MAX];
 277
 278         if (gethostname(buf, sizeof(buf)) == -1) {
 279                 warn("hostname");
 280                 return smprintf("%s", UNKNOWN_STR);
 281         }
 282
 283         return smprintf("%s", buf);
 284 }
 285
 286 static char *
 287 ip(const char *iface)
 288 {
 289         struct ifaddrs *ifaddr, *ifa;
 290         int s;
 291         char host[NI_MAXHOST];
 292
 293         if (getifaddrs(&ifaddr) == -1) {
 294                 warn("Failed to get IP address for interface %s", iface);
 295                 return smprintf("%s", UNKNOWN_STR);
 296         }
 297
 298         for (ifa = ifaddr; ifa != NULL; ifa = ifa->ifa_next) {
 299                 if (ifa->ifa_addr == NULL) {
 300                         continue;
 301                 }
 302                 s = getnameinfo(ifa->ifa_addr, sizeof(struct sockaddr_in), host, NI_MAXHOST, NULL, 0, NI_NUMERICHOST);
 303                 if ((strcmp(ifa->ifa_name, iface) == 0) && (ifa->ifa_addr->sa_family == AF_INET)) {
 304                         if (s != 0) {
 305                                 warnx("Failed to get IP address for interface %s", iface);
 306                                 return smprintf("%s", UNKNOWN_STR);
 307                         }
 308                         return smprintf("%s", host);
 309                 }
 310         }
 311
 312         freeifaddrs(ifaddr);
 313
 314         return smprintf("%s", UNKNOWN_STR);
 315 }
 316
 317 static char *
 318 kernel_release(void)
 319 {
 320         struct utsname udata;
 321
 322         if (uname(&udata) < 0) {
 323                 return smprintf(UNKNOWN_STR);
 324         }
 325
 326         return smprintf("%s", udata.release);
 327 }
 328
 329 static char *
 330 load_avg(void)
 331 {
 332         double avgs[3];
 333
 334         if (getloadavg(avgs, 3) < 0) {
 335                 warnx("Failed to get the load avg");
 336                 return smprintf("%s", UNKNOWN_STR);
 337         }
 338
 339         return smprintf("%.2f %.2f %.2f", avgs[0], avgs[1], avgs[2]);
 340 }
 341
 342 static char *
 343 ram_free(void)
 344 {
 345         long free;
 346         FILE *fp;
 347
 348         fp = fopen("/proc/meminfo", "r");
 349         if (fp == NULL) {
 350                 warn("Failed to open file /proc/meminfo");
 351                 return smprintf("%s", UNKNOWN_STR);
 352         }
 353         fscanf(fp, "MemFree: %ld kB\n", &free);
 354         fclose(fp);
 355
 356         return smprintf("%f", (float)free / 1024 / 1024);
 357 }
 358
 359 static char *
 360 ram_perc(void)
 361 {
 362         long total, free, buffers, cached;
 363         FILE *fp;
 364
 365         fp = fopen("/proc/meminfo", "r");
 366         if (fp == NULL) {
 367                 warn("Failed to open file /proc/meminfo");
 368                 return smprintf("%s", UNKNOWN_STR);
 369         }
 370         fscanf(fp, "MemTotal: %ld kB\n", &total);
 371         fscanf(fp, "MemFree: %ld kB\n", &free);
 372         fscanf(fp, "MemAvailable: %ld kB\nBuffers: %ld kB\n", &buffers, &buffers);
 373         fscanf(fp, "Cached: %ld kB\n", &cached);
 374         fclose(fp);
 375
 376         return smprintf("%d%%", 100 * ((total - free) - (buffers + cached)) / total);
 377 }
 378
 379 static char *
 380 ram_total(void)
 381 {
 382         long total;
 383         FILE *fp;
 384
 385         fp = fopen("/proc/meminfo", "r");
 386         if (fp == NULL) {
 387                 warn("Failed to open file /proc/meminfo");
 388                 return smprintf("%s", UNKNOWN_STR);
 389         }
 390         fscanf(fp, "MemTotal: %ld kB\n", &total);
 391         fclose(fp);
 392
 393         return smprintf("%f", (float)total / 1024 / 1024);
 394 }
 395
 396 static char *
 397 ram_used(void)
 398 {
 399         long free, total, buffers, cached;
 400         FILE *fp;
 401
 402         fp = fopen("/proc/meminfo", "r");
 403         if (fp == NULL) {
 404                 warn("Failed to open file /proc/meminfo");
 405                 return smprintf("%s", UNKNOWN_STR);
 406         }
 407         fscanf(fp, "MemTotal: %ld kB\n", &total);
 408         fscanf(fp, "MemFree: %ld kB\n", &free);
 409         fscanf(fp, "MemAvailable: %ld kB\nBuffers: %ld kB\n", &buffers, &buffers);
 410         fscanf(fp, "Cached: %ld kB\n", &cached);
 411         fclose(fp);
 412
 413         return smprintf("%f", (float)(total - free - buffers - cached) / 1024 / 1024);
 414 }
 415
 416 static char *
 417 run_command(const char *cmd)
 418 {
 419         char *nlptr;
 420         FILE *fp;
 421         char buf[1024] = UNKNOWN_STR;
 422
 423         fp = popen(cmd, "r");
 424         if (fp == NULL) {
 425                 warn("Failed to get command output for %s", cmd);
 426                 return smprintf("%s", UNKNOWN_STR);
 427         }
 428         fgets(buf, sizeof(buf), fp);
 429         pclose(fp);
 430         buf[strlen(buf)] = '\0';
 431
 432         if ((nlptr = strstr(buf, "\n")) != NULL) {
 433                 nlptr[0] = '\0';
 434         }
 435
 436         return smprintf("%s", buf);
 437 }
 438
 439 static char *
 440 swap_free(void)
 441 {
 442         long total, free;
 443         FILE *fp;
 444         char buf[2048];
 445         size_t bytes_read;
 446         char *match;
 447
 448         fp = fopen("/proc/meminfo", "r");
 449         if (fp == NULL) {
 450                 warn("Failed to open file /proc/meminfo");
 451                 return smprintf("%s", UNKNOWN_STR);
 452         }
 453
 454         if ((bytes_read = fread(buf, sizeof(char), sizeof(buf), fp)) == 0) {
 455                 warn("swap_free: read error");
 456                 fclose(fp);
 457                 return smprintf("%s", UNKNOWN_STR);
 458         }
 459
 460         buf[bytes_read] = '\0';
 461         fclose(fp);
 462
 463         if ((match = strstr(buf, "SwapTotal")) == NULL) {
 464                 return smprintf("%s", UNKNOWN_STR);
 465         }
 466         sscanf(match, "SwapTotal: %ld kB\n", &total);
 467
 468         if ((match = strstr(buf, "SwapFree")) == NULL) {
 469                 return smprintf("%s", UNKNOWN_STR);
 470         }
 471         sscanf(match, "SwapFree: %ld kB\n", &free);
 472
 473         return smprintf("%f", (float)free / 1024 / 1024);
 474 }
 475
 476 static char *
 477 swap_perc(void)
 478 {
 479         long total, free, cached;
 480         FILE *fp;
 481         char buf[2048];
 482         size_t bytes_read;
 483         char *match;
 484
 485         fp = fopen("/proc/meminfo", "r");
 486         if (fp == NULL) {
 487                 warn("Failed to open file /proc/meminfo");
 488                 return smprintf("%s", UNKNOWN_STR);
 489         }
 490
 491         if ((bytes_read = fread(buf, sizeof(char), sizeof(buf), fp)) == 0) {
 492                 warn("swap_perc: read error");
 493                 fclose(fp);
 494                 return smprintf("%s", UNKNOWN_STR);
 495         }
 496
 497         buf[bytes_read] = '\0';
 498         fclose(fp);
 499
 500         if ((match = strstr(buf, "SwapTotal")) == NULL) {
 501                 return smprintf("%s", UNKNOWN_STR);
 502         }
 503         sscanf(match, "SwapTotal: %ld kB\n", &total);
 504
 505         if ((match = strstr(buf, "SwapCached")) == NULL) {
 506                 return smprintf("%s", UNKNOWN_STR);
 507         }
 508         sscanf(match, "SwapCached: %ld kB\n", &cached);
 509
 510         if ((match = strstr(buf, "SwapFree")) == NULL) {
 511                 return smprintf("%s", UNKNOWN_STR);
 512         }
 513         sscanf(match, "SwapFree: %ld kB\n", &free);
 514
 515         return smprintf("%d%%", 100 * (total - free - cached) / total);
 516 }
 517
 518 static char *
 519 swap_total(void)
 520 {
 521         long total;
 522         FILE *fp;
 523         char buf[2048];
 524         size_t bytes_read;
 525         char *match;
 526
 527         fp = fopen("/proc/meminfo", "r");
 528         if (fp == NULL) {
 529                 warn("Failed to open file /proc/meminfo");
 530                 return smprintf("%s", UNKNOWN_STR);
 531         }
 532         if ((bytes_read = fread(buf, sizeof(char), sizeof(buf), fp)) == 0) {
 533                 warn("swap_total: read error");
 534                 fclose(fp);
 535                 return smprintf("%s", UNKNOWN_STR);
 536         }
 537
 538         buf[bytes_read] = '\0';
 539         fclose(fp);
 540
 541         if ((match = strstr(buf, "SwapTotal")) == NULL) {
 542                 return smprintf("%s", UNKNOWN_STR);
 543         }
 544         sscanf(match, "SwapTotal: %ld kB\n", &total);
 545
 546         return smprintf("%f", (float)total / 1024 / 1024);
 547 }
 548
 549 static char *
 550 swap_used(void)
 551 {
 552         long total, free, cached;
 553         FILE *fp;
 554         char buf[2048];
 555         size_t bytes_read;
 556         char *match;
 557
 558         fp = fopen("/proc/meminfo", "r");
 559         if (fp == NULL) {
 560                 warn("Failed to open file /proc/meminfo");
 561                 return smprintf("%s", UNKNOWN_STR);
 562         }
 563         if ((bytes_read = fread(buf, sizeof(char), sizeof(buf), fp)) == 0) {
 564                 warn("swap_used: read error");
 565                 fclose(fp);
 566                 return smprintf("%s", UNKNOWN_STR);
 567         }
 568
 569         buf[bytes_read] = '\0';
 570         fclose(fp);
 571
 572         if ((match = strstr(buf, "SwapTotal")) == NULL) {
 573                 return smprintf("%s", UNKNOWN_STR);
 574         }
 575         sscanf(match, "SwapTotal: %ld kB\n", &total);
 576
 577         if ((match = strstr(buf, "SwapCached")) == NULL) {
 578                 return smprintf("%s", UNKNOWN_STR);
 579         }
 580         sscanf(match, "SwapCached: %ld kB\n", &cached);
 581
 582         if ((match = strstr(buf, "SwapFree")) == NULL) {
 583                 return smprintf("%s", UNKNOWN_STR);
 584         }
 585         sscanf(match, "SwapFree: %ld kB\n", &free);
 586
 587         return smprintf("%f", (float)(total - free - cached) / 1024 / 1024);
 588 }
 589
 590 static char *
 591 temp(const char *file)
 592 {
 593         int temp;
 594         FILE *fp;
 595
 596         fp = fopen(file, "r");
 597         if (fp == NULL) {
 598                 warn("Failed to open file %s", file);
 599                 return smprintf("%s", UNKNOWN_STR);
 600         }
 601         fscanf(fp, "%d", &temp);
 602         fclose(fp);
 603
 604         return smprintf("%d°C", temp / 1000);
 605 }
 606
 607 static char *
 608 uptime(void)
 609 {
 610         struct sysinfo info;
 611         int h = 0;
 612         int m = 0;
 613
 614         sysinfo(&info);
 615         h = info.uptime / 3600;
 616         m = (info.uptime - h * 3600 ) / 60;
 617
 618         return smprintf("%dh %dm", h, m);
 619 }
 620
 621 static char *
 622 username(void)
 623 {
 624         uid_t uid = geteuid();
 625         struct passwd *pw = getpwuid(uid);
 626
 627         if (pw == NULL) {
 628                 warn("Failed to get username");
 629                 return smprintf("%s", UNKNOWN_STR);
 630         }
 631
 632         return smprintf("%s", pw->pw_name);
 633 }
 634
 635 static char *
 636 uid(void)
 637 {
 638         return smprintf("%d", geteuid());
 639 }
 640
 641
 642 static char *
 643 vol_perc(const char *card)
 644 {
 645         int mute;
 646         long int vol, max, min;
 647         snd_mixer_t *handle;
 648         snd_mixer_elem_t *elem;
 649         snd_mixer_selem_id_t *s_elem;
 650
 651         snd_mixer_open(&handle, 0);
 652         snd_mixer_attach(handle, card);
 653         snd_mixer_selem_register(handle, NULL, NULL);
 654         snd_mixer_load(handle);
 655         snd_mixer_selem_id_malloc(&s_elem);
 656         snd_mixer_selem_id_set_name(s_elem, "Master");
 657         elem = snd_mixer_find_selem(handle, s_elem);
 658
 659         if (elem == NULL) {
 660                 snd_mixer_selem_id_free(s_elem);
 661                 snd_mixer_close(handle);
 662                 warn("Failed to get volume percentage for %s", card);
 663                 return smprintf("%s", UNKNOWN_STR);
 664         }
 665
 666         snd_mixer_handle_events(handle);
 667         snd_mixer_selem_get_playback_volume_range(elem, &min, &max);
 668         snd_mixer_selem_get_playback_volume(elem, 0, &vol);
 669         snd_mixer_selem_get_playback_switch(elem, 0, &mute);
 670
 671         snd_mixer_selem_id_free(s_elem);
 672         snd_mixer_close(handle);
 673
 674         if (!mute)
 675                 return smprintf("mute");
 676         else if (max == 0)
 677                 return smprintf("0%%");
 678         else
 679                 return smprintf("%lu%%", ((uint_fast16_t)(vol * 100) / max));
 680 }
 681
 682 static char *
 683 wifi_perc(const char *iface)
 684 {
 685         int perc;
 686         char buf[255];
 687         char *datastart;
 688         char status[5];
 689         FILE *fp;
 690
 691         ccat(3, "/sys/class/net/", iface, "/operstate");
 692         fp = fopen(concat, "r");
 693         if (fp == NULL) {
 694                 warn("Failed to open file %s", concat);
 695                 return smprintf("%s", UNKNOWN_STR);
 696         }
 697         fgets(status, 5, fp);
 698         fclose(fp);
 699         if(strcmp(status, "up\n") != 0) {
 700                 return smprintf("%s", UNKNOWN_STR);
 701         }
 702
 703         fp = fopen("/proc/net/wireless", "r");
 704         if (fp == NULL) {
 705                 warn("Failed to open file /proc/net/wireless");
 706                 return smprintf("%s", UNKNOWN_STR);
 707         }
 708         ccat(2, iface, ":");
 709         fgets(buf, sizeof(buf), fp);
 710         fgets(buf, sizeof(buf), fp);
 711         fgets(buf, sizeof(buf), fp);
 712         fclose(fp);
 713
 714         if ((datastart = strstr(buf, concat)) == NULL) {
 715                 return smprintf("%s", UNKNOWN_STR);
 716         }
 717         datastart = (datastart+(strlen(iface)+1));
 718         sscanf(datastart + 1, " %*d   %d  %*d  %*d                %*d      %*d          %*d              %*d      %*d            %*d", &perc);
 719
 720         return smprintf("%d%%", perc);
 721 }
 722
 723 static char *
 724 wifi_essid(const char *iface)
 725 {
 726         char id[IW_ESSID_MAX_SIZE+1];
 727         int sockfd = socket(AF_INET, SOCK_DGRAM, 0);
 728         struct iwreq wreq;
 729
 730         memset(&wreq, 0, sizeof(struct iwreq));
 731         wreq.u.essid.length = IW_ESSID_MAX_SIZE+1;
 732         snprintf(wreq.ifr_name, sizeof(wreq.ifr_name), "%s", iface);
 733
 734         if (sockfd == -1) {
 735                 warn("Failed to get ESSID for interface %s", iface);
 736                 return smprintf("%s", UNKNOWN_STR);
 737         }
 738         wreq.u.essid.pointer = id;
 739         if (ioctl(sockfd,SIOCGIWESSID, &wreq) == -1) {
 740                 warn("Failed to get ESSID for interface %s", iface);
 741                 return smprintf("%s", UNKNOWN_STR);
 742         }
 743
 744         close(sockfd);
 745
 746         if (strcmp((char *)wreq.u.essid.pointer, "") == 0)
 747                 return smprintf("%s", UNKNOWN_STR);
 748         else
 749                 return smprintf("%s", (char *)wreq.u.essid.pointer);
 750 }
 751
 752 static void
 753 sighandler(const int signo)
 754 {
 755         if (signo == SIGTERM || signo == SIGINT) {
 756                 done = 1;
 757         }
 758 }
 759
 760 static void
 761 usage(int eval)
 762 {
 763         fprintf(stderr, "usage: %s [-d] [-o] [-v] [-h]\n", argv0);
 764         exit(eval);
 765 }
 766
 767 int
 768 main(int argc, char *argv[])
 769 {
 770         unsigned short int i;
 771         char status_string[2048];
 772         char *res, *element;
 773         struct arg argument;
 774         struct sigaction act;
 775
 776         ARGBEGIN {
 777                 case 'd':
 778                         dflag = 1;
 779                         break;
 780                 case 'o':
 781                         oflag = 1;
 782                         break;
 783                 case 'v':
 784                         printf("slstatus %s (C) 2016 slstatus engineers\n", VERSION);
 785                         return 0;
 786                 case 'h':
 787                         usage(0);
 788                 default:
 789                         usage(1);
 790         } ARGEND
 791
 792         if (dflag && oflag) {
 793                 usage(1);
 794         }
 795         if (dflag && daemon(1, 1) < 0) {
 796                 err(1, "daemon");
 797         }
 798
 799         memset(&act, 0, sizeof(act));
 800         act.sa_handler = sighandler;
 801         sigaction(SIGINT,  &act, 0);
 802         sigaction(SIGTERM, &act, 0);
 803
 804         if (!oflag) {
 805                 dpy = XOpenDisplay(NULL);
 806         }
 807
 808         setlocale(LC_ALL, "");
 809
 810         while (!done) {
 811                 status_string[0] = '\0';
 812
 813                 for (i = 0; i < sizeof(args) / sizeof(args[0]); ++i) {
 814                         argument = args[i];
 815                         if (argument.args == NULL) {
 816                                 res = argument.func();
 817                         } else {
 818                                 res = argument.func(argument.args);
 819                         }
 820                         element = smprintf(argument.fmt, res);
 821                         if (element == NULL) {
 822                                 element = smprintf("%s", UNKNOWN_STR);
 823                                 warnx("Failed to format output");
 824                         }
 825                         if (strlcat(status_string, element, sizeof(status_string)) >= sizeof(status_string)) {
 826                                 warnx("Output too long");
 827                         }
 828                         free(res);
 829                         free(element);
 830                 }
 831
 832                 if (!oflag) {
 833                         XStoreName(dpy, DefaultRootWindow(dpy), status_string);
 834                         XSync(dpy, False);
 835                 } else {
 836                         printf("%s\n", status_string);
 837                 }
 838
 839                 if ((UPDATE_INTERVAL - delay) <= 0) {
 840                         delay = 0;
 841                         continue;
 842                 } else {
 843                         sleep(UPDATE_INTERVAL - delay);
 844                         delay = 0;
 845                 }
 846         }
 847
 848         if (!oflag) {
 849                 XStoreName(dpy, DefaultRootWindow(dpy), NULL);
 850                 XCloseDisplay(dpy);
 851         }
 852
 853         return 0;
 854 }