arexxd.c

   1 /*
   2  *      Linux Interfece for Arexx Data Loggers
   3  *
   4  *      (c) 2011-2012 Martin Mares <mj@ucw.cz>
   5  */
   6
   7 #include <stdio.h>
   8 #include <stdarg.h>
   9 #include <stdlib.h>
  10 #include <string.h>
  11 #include <unistd.h>
  12 #include <fcntl.h>
  13 #include <math.h>
  14 #include <time.h>
  15 #include <getopt.h>
  16 #include <syslog.h>
  17 #include <signal.h>
  18 #include <sys/stat.h>
  19 #include <libusb-1.0/libusb.h>
  20 #include <rrd.h>
  21
  22 #define DEFAULT_LOG_DIR "/var/log/arexxd"
  23
  24 typedef unsigned char byte;
  25 static libusb_context *usb_ctxt;
  26 static libusb_device_handle *devh;
  27
  28 static int use_syslog;
  29 static int debug_mode;
  30 static int debug_packets;
  31 static int debug_raw_data;
  32 static int debug_usb;
  33 static char *log_dir = DEFAULT_LOG_DIR;
  34
  35 static void die(char *fmt, ...)
  36 {
  37         va_list args;
  38         va_start(args, fmt);
  39         if (use_syslog)
  40                 vsyslog(LOG_CRIT, fmt, args);
  41         else {
  42                 vfprintf(stderr, fmt, args);
  43                 fprintf(stderr, "\n");
  44         }
  45         va_end(args);
  46         exit(1);
  47 }
  48
  49 static void log_error(char *fmt, ...)
  50 {
  51         va_list args;
  52         va_start(args, fmt);
  53         if (use_syslog)
  54                 vsyslog(LOG_ERR, fmt, args);
  55         else {
  56                 vfprintf(stderr, fmt, args);
  57                 fprintf(stderr, "\n");
  58         }
  59         va_end(args);
  60 }
  61
  62 static void log_info(char *fmt, ...)
  63 {
  64         va_list args;
  65         va_start(args, fmt);
  66         if (use_syslog)
  67                 vsyslog(LOG_INFO, fmt, args);
  68         else {
  69                 vfprintf(stderr, fmt, args);
  70                 fprintf(stderr, "\n");
  71         }
  72         va_end(args);
  73 }
  74
  75 static void log_pkt(char *fmt, ...)
  76 {
  77         if (!debug_packets)
  78                 return;
  79         va_list args;
  80         va_start(args, fmt);
  81         vprintf(fmt, args);
  82         va_end(args);
  83 }
  84
  85 /*** RRD interface ***/
  86
  87 #define MAX_ARGS 20
  88 #define MAX_ARG_SIZE 1024
  89
  90 static int arg_cnt;
  91 static char *arg_ptr[MAX_ARGS+1];
  92 static char arg_buf[MAX_ARG_SIZE];
  93 static int arg_pos;
  94
  95 static void arg_new(void)
  96 {
  97         arg_cnt = 1;
  98         arg_pos = 0;
  99         arg_ptr[0] = "rrdtool";
 100 }
 101
 102 static void arg_push(const char *fmt, ...)
 103 {
 104         if (arg_cnt >= MAX_ARGS)
 105                 die("MAX_ARGS exceeded");
 106         va_list va;
 107         va_start(va, fmt);
 108         int len = 1 + vsnprintf(arg_buf + arg_pos, MAX_ARG_SIZE - arg_pos, fmt, va);
 109         if (arg_pos + len > MAX_ARG_SIZE)
 110                 die("MAX_ARG_SIZE exceeded");
 111         arg_ptr[arg_cnt++] = arg_buf + arg_pos;
 112         arg_ptr[arg_cnt] = NULL;
 113         arg_pos += len;
 114 }
 115
 116 static void rrd_point(time_t t, const char *name, double val, char *unit)
 117 {
 118         char rr_name[256];
 119         snprintf(rr_name, sizeof(rr_name), "sensor-%s.rrd", name);
 120
 121         struct stat st;
 122         if (stat(rr_name, &st) < 0 || !st.st_size) {
 123                 // We have to create the RRD
 124                 log_info("Creating %s", rr_name);
 125                 arg_new();
 126                 arg_push(rr_name);
 127                 arg_push("--start");
 128                 arg_push("%d", (int) time(NULL) - 28*86400);
 129                 arg_push("--step");
 130                 arg_push("60");
 131                 if (!strcmp(unit, "%RH"))
 132                         arg_push("DS:rh:GAUGE:300:0:100");
 133                 else if (!strcmp(unit, "ppm"))
 134                         arg_push("DS:ppm:GAUGE:300:0:1000000");
 135                 else
 136                         arg_push("DS:temp:GAUGE:300:-200:200");
 137                 arg_push("RRA:AVERAGE:0.25:1:20160");           // Last 14 days with full resolution
 138                 arg_push("RRA:AVERAGE:0.25:60:88800");          // Last 10 years with 1h resolution
 139                 arg_push("RRA:MIN:0.25:60:88800");              // including minima and maxima
 140                 arg_push("RRA:MAX:0.25:60:88800");
 141                 rrd_create(arg_cnt, arg_ptr);
 142                 if (rrd_test_error()) {
 143                         log_error("rrd_create on %s failed: %s", rr_name, rrd_get_error());
 144                         return;
 145                 }
 146         }
 147
 148         arg_new();
 149         arg_push(rr_name);
 150         arg_push("%d:%f", t, val);
 151         rrd_update(arg_cnt, arg_ptr);
 152         if (rrd_test_error())
 153                 log_error("rrd_update on %s failed: %s", rr_name, rrd_get_error());
 154 }
 155
 156 /*** Transforms ***/
 157
 158 #define TIME_OFFSET 946681200           // Timestamp of 2000-01-01 00:00:00
 159
 160 static int data_point_counter;          // Since last log message
 161
 162 static double correct_point(int id, double val, const char **name)
 163 {
 164         /*
 165          *  Manually calculated corrections and renames for my sensors.
 166          *  Replace with your formulae.
 167          */
 168         switch (id) {
 169                 case 10415:
 170                         *name = "ursarium";
 171                         return val - 0.93;
 172                 case 10707:
 173                         *name = "balcony";
 174                         return val - 0.71;
 175                 case 19246:
 176                         *name = "catarium";
 177                         return val + 0.49;
 178                 case 19247:
 179                         *name = "catarium-rh";
 180                         return val;
 181                 case 12133:
 182                         *name = "outside";
 183                         return val + 0.44;
 184                 default:
 185                         return val;
 186         }
 187 }
 188
 189 static void cooked_point(time_t t, int id, double val, char *unit, int q)
 190 {
 191         char namebuf[16];
 192         snprintf(namebuf, sizeof(namebuf), "%d", id);
 193         const char *name = namebuf;
 194
 195         double val2 = correct_point(id, val, &name);
 196
 197         if (debug_raw_data) {
 198                 struct tm tm;
 199                 localtime_r(&t, &tm);
 200                 char tbuf[64];
 201                 strftime(tbuf, sizeof(tbuf), "%Y-%m-%d %H:%M:%S", &tm);
 202                 printf("== %s id=%d name=%s val=%.3f val2=%.3f unit=%s q=%d\n", tbuf, id, name, val, val2, unit, q);
 203         }
 204
 205         data_point_counter++;
 206         rrd_point(t, name, val2, unit);
 207 }
 208
 209 static void raw_point(int t, int id, int raw, int q)
 210 {
 211         /*
 212          *  The binary blob provided by Arexx contains an embedded XML fragment
 213          *  with descriptions of all known sensor types. If you want to see it,
 214          *  grep the blob for "<deviceinfo>". The meanings of the parameters are
 215          *  as follows:
 216          *
 217          *      m1, m2          Device type matches if (raw_sensor_id & m1) == m2
 218          *      type            Unit measured by the sensor (1=Celsius, 2=RH%, 3=CO2 ppm)
 219          *      dm              User-visible sensor ID = raw_sensor_id & dm
 220          *      i               1 if the raw value is signed
 221          *      p[]             Coefficients of transformation polynomial (x^0 first)
 222          *      vLo, vUp        Upper and lower bound on the final value
 223          *      scale           Scaling function:
 224          *                              0 = identity (default)
 225          *                              1 = 10^x
 226          *                              2 = exp(x)
 227          *                              3 = (x < 0) ? 0 : log10(x)
 228          *                              4 = (x < 0) ? 0 : log(x)
 229          *
 230          *  The raw values are transformed this way:
 231          *      - sign-extend if signed
 232          *      - apply the transformation polynomial
 233          *      - apply the scaling function
 234          *      - drop if outside the interval [vLo,vUp]
 235          *
 236          *  This function applies the necessary transform for sensors we've
 237          *  seen in the wild. We deliberately ignore the "dm" parameter as we want
 238          *  to report different channels of a single sensor as multiple sensors.
 239          */
 240
 241         double z = raw;
 242         double hi, lo;
 243         char *unit;
 244         int idhi = id & 0xf000;
 245
 246         if (idhi == 0x1000) {
 247                 z = 0.02*z - 273.15;
 248                 lo = -200;
 249                 hi = 600;
 250                 unit = "C";
 251         } else if (idhi == 0x2000) {
 252                 if (raw >= 0x8000)
 253                         z -= 0x10000;
 254                 z /= 128;
 255                 lo = -60;
 256                 hi = 125;
 257                 unit = "C";
 258         } else if (idhi == 0x4000) {
 259                 if (!(id & 1)) {
 260                         z = z/100 - 39.6;
 261                         lo = -60;
 262                         hi = 125;
 263                         unit = "C";
 264                 } else {
 265                         z = -2.8e-6*z*z + 0.0405*z - 4;
 266                         lo = 0;
 267                         hi = 100.1;
 268                         unit = "%RH";
 269                 }
 270         } else if (idhi == 0x6000) {
 271                 if (!(id & 1)) {
 272                         if (raw >= 0x8000)
 273                                 z -= 0x10000;
 274                         z /= 128;
 275                         lo = -60;
 276                         hi = 125;
 277                         unit = "C";
 278                 } else {
 279                         z = -3.8123e-11*z;
 280                         z = (z + 1.9184e-7) * z;
 281                         z = (z - 1.0998e-3) * z;
 282                         z += 6.56;
 283                         z = pow(10, z);
 284                         lo = 0;
 285                         hi = 1e6;
 286                         unit = "ppm";
 287                 }
 288         } else {
 289                 log_error("Unknown sensor type 0x%04x", id);
 290                 return;
 291         }
 292
 293         if (z < lo || z > hi) {
 294                 log_error("Sensor %d: value %f out of range", id, z);
 295                 return;
 296         }
 297
 298         cooked_point(t + TIME_OFFSET, id, z, unit, q);
 299 }
 300
 301 /*** USB interface ***/
 302
 303 static int find_device(void)
 304 {
 305         libusb_device **devlist;
 306         ssize_t devn = libusb_get_device_list(usb_ctxt, &devlist);
 307         if (devn < 0) {
 308                 log_error("Cannot enumerate USB devices: error %d", (int) devn);
 309                 return 0;
 310         }
 311
 312         for (ssize_t i=0; i<devn; i++) {
 313                 struct libusb_device_descriptor desc;
 314                 libusb_device *dev = devlist[i];
 315                 if (!libusb_get_device_descriptor(dev, &desc)) {
 316                         if (desc.idVendor == 0x0451 && desc.idProduct == 0x3211) {
 317                                 log_info("Arexx data logger found at usb%d.%d", libusb_get_bus_number(dev), libusb_get_device_address(dev));
 318                                 int err;
 319                                 if (err = libusb_open(dev, &devh)) {
 320                                         log_error("libusb_open() failed: error %d", err);
 321                                         goto failed;
 322                                 }
 323                                 if (err = libusb_claim_interface(devh, 0)) {
 324                                         log_error("libusb_claim_interface() failed: error %d", err);
 325                                         libusb_close(devh);
 326                                         goto failed;
 327                                 }
 328                                 libusb_free_device_list(devlist, 1);
 329                                 return 1;
 330                         }
 331                 }
 332         }
 333
 334 failed:
 335         libusb_free_device_list(devlist, 1);
 336         return 0;
 337 }
 338
 339 static void release_device(void)
 340 {
 341         libusb_release_interface(devh, 0);
 342         libusb_reset_device(devh);
 343         libusb_close(devh);
 344         devh = NULL;
 345 }
 346
 347 static void dump_packet(byte *pkt)
 348 {
 349         for (int i=0; i<64; i++) {
 350                 if (!(i % 16))
 351                         log_pkt("\t%02x:", i);
 352                 log_pkt(" %02x", pkt[i]);
 353                 if (i % 16 == 15)
 354                         log_pkt("\n");
 355         }
 356 }
 357
 358 static int send_and_receive(byte *req, byte *reply)
 359 {
 360         if (debug_packets) {
 361                 time_t t = time(NULL);
 362                 struct tm tm;
 363                 localtime_r(&t, &tm);
 364
 365                 char tbuf[64];
 366                 strftime(tbuf, sizeof(tbuf), "%Y-%m-%d %H:%M:%S", &tm);
 367                 log_pkt("## %s\n", tbuf);
 368         }
 369
 370         int err, transferred;
 371         if (err = libusb_bulk_transfer(devh, 0x01, req, 64, &transferred, 200)) {
 372                 if (err == LIBUSB_ERROR_TIMEOUT) {
 373                         log_pkt(">> xmit timed out\n");
 374                         return 0;
 375                 }
 376                 log_pkt(">> xmit error %d\n", err);
 377                 log_error("Transmit error: %d", err);
 378                 return err;
 379         }
 380         if (debug_packets) {
 381                 log_pkt(">> xmit %d bytes\n", transferred);
 382                 dump_packet(req);
 383         }
 384         if (err = libusb_bulk_transfer(devh, 0x81, reply, 64, &transferred, 200)) {
 385                 if (err == LIBUSB_ERROR_TIMEOUT) {
 386                         log_pkt("<< recv timed out\n");
 387                         return 0;
 388                 }
 389                 log_pkt("<< recv error %d\n", err);
 390                 log_error("Receive error: %d", err);
 391                 return err;
 392         }
 393         if (debug_packets)
 394                 log_pkt("<< recv %d bytes\n", transferred);
 395         while (transferred < 64)
 396                 reply[transferred++] = 0xff;
 397         if (debug_packets)
 398                 dump_packet(reply);
 399         return 1;
 400 }
 401
 402 static unsigned int get_be16(byte *p)
 403 {
 404         return p[1] | (p[0] << 8);
 405 }
 406
 407 static unsigned int get_le16(byte *p)
 408 {
 409         return p[0] | (p[1] << 8);
 410 }
 411
 412 static unsigned int get_le32(byte *p)
 413 {
 414         return get_le16(p) | (get_le16(p+2) << 16);
 415 }
 416
 417 static void put_le16(byte *p, unsigned int x)
 418 {
 419         p[0] = x;
 420         p[1] = x >> 8;
 421 }
 422
 423 static void put_le32(byte *p, unsigned int x)
 424 {
 425         put_le16(p, x);
 426         put_le16(p+2, x>>16);
 427 }
 428
 429 static int parse_packet(byte *reply)
 430 {
 431         if (reply[0]) {
 432                 log_error("Unknown packet type %02x", reply[0]);
 433                 return 0;
 434         }
 435
 436         int pos = 1;
 437         int points = 0;
 438         while (pos < 64) {
 439                 byte *p = reply + pos;
 440                 int len = p[0];
 441                 if (!len || len == 0xff)
 442                         break;
 443                 if (len < 9 || len > 10) {
 444                         log_error("Unknown tuple length %02x", len);
 445                         break;
 446                 }
 447                 if (pos + len > 64) {
 448                         log_error("Tuple truncated");
 449                         break;
 450                 }
 451                 int id = get_le16(p+1);
 452                 int raw = get_be16(p+3);
 453                 int t = get_le32(p+5);
 454                 int q = (len > 9) ? p[9] : -1;
 455                 if (debug_raw_data) {
 456                         printf("... %02x: id=%d raw=%d t=%d", len, id, raw, t);
 457                         if (len > 9)
 458                                 printf(" q=%d", q);
 459                         printf("\n");
 460                 }
 461                 raw_point(t, id, raw, q);
 462                 pos += len;
 463                 points++;
 464         }
 465
 466         return points;
 467 }
 468
 469 static void set_clock(void)
 470 {
 471         byte req[64], reply[64];
 472         memset(req, 0, 64);
 473         req[0] = 4;
 474         time_t t = time(NULL);
 475         put_le32(req+1, t-TIME_OFFSET);
 476         send_and_receive(req, reply);
 477
 478 #if 0
 479         /*
 480          *  Original software also sends a packet with type 3 and the timestamp,
 481          *  but it does not make any sense, especially as they ignore the sensor
 482          *  readings in the answer.
 483          */
 484         req[0] = 3;
 485         send_and_receive(req, reply);
 486         parse_packet(reply);
 487 #endif
 488 }
 489
 490 /*** Main ***/
 491
 492 static sigset_t term_sigs;
 493 static volatile sig_atomic_t want_shutdown;
 494
 495 static void sigterm_handler(int sig __attribute__((unused)))
 496 {
 497         want_shutdown = 1;
 498 }
 499
 500 static void interruptible_msleep(int ms)
 501 {
 502         sigprocmask(SIG_UNBLOCK, &term_sigs, NULL);
 503         struct timespec ts = { .tv_sec = ms/1000, .tv_nsec = (ms%1000) * 1000000 };
 504         nanosleep(&ts, NULL);
 505         sigprocmask(SIG_BLOCK, &term_sigs, NULL);
 506 }
 507
 508 static const struct option long_options[] = {
 509         { "debug",              0, NULL, 'd' },
 510         { "log-dir",            1, NULL, 'l' },
 511         { "debug-packets",      0, NULL, 'p' },
 512         { "debug-raw",          0, NULL, 'r' },
 513         { NULL,                 0, NULL, 0 },
 514 };
 515
 516 static void usage(void)
 517 {
 518         fprintf(stderr, "\n\
 519 Usage: arexxd <options>\n\
 520 \n\
 521 Options:\n\
 522 -d, --debug             Debug mode (no chdir, no fork, no syslog)\n\
 523 -l, --log-dir=<dir>     Directory where all received data should be stored\n\
 524 -p, --debug-packets     Log all packets sent and received\n\
 525 -r, --debug-raw         Log conversion from raw values\n\
 526 -u, --debug-usb         Enable libusb debug messages (to stdout/stderr)\n\
 527 ");
 528         exit(1);
 529 }
 530
 531 int main(int argc, char **argv)
 532 {
 533         int opt;
 534         while ((opt = getopt_long(argc, argv, "dl:pru", long_options, NULL)) >= 0)
 535                 switch (opt) {
 536                         case 'd':
 537                                 debug_mode++;
 538                                 break;
 539                         case 'l':
 540                                 log_dir = optarg;
 541                                 break;
 542                         case 'p':
 543                                 debug_packets++;
 544                                 break;
 545                         case 'r':
 546                                 debug_raw_data++;
 547                                 break;
 548                         case 'u':
 549                                 debug_usb++;
 550                                 break;
 551                         default:
 552                                 usage();
 553                 }
 554         if (optind < argc)
 555                 usage();
 556
 557         int err;
 558         if (err = libusb_init(&usb_ctxt))
 559                 die("Cannot initialize libusb: error %d", err);
 560         if (debug_usb)
 561                 libusb_set_debug(usb_ctxt, 3);
 562
 563         if (!debug_mode) {
 564                 if (chdir(log_dir) < 0)
 565                         die("Cannot change directory to %s: %m", log_dir);
 566                 if (debug_packets || debug_raw_data) {
 567                         close(1);
 568                         if (open("debug", O_WRONLY | O_CREAT | O_APPEND, 0666) < 0)
 569                                 die("Cannot open debug log: %m");
 570                         setlinebuf(stdout);
 571                 }
 572                 openlog("arexxd", LOG_NDELAY, LOG_DAEMON);
 573                 pid_t pid = fork();
 574                 if (pid < 0)
 575                         die("fork() failed: %m");
 576                 if (pid)
 577                         return 0;
 578                 setsid();
 579                 use_syslog = 1;
 580         }
 581
 582         struct sigaction sa = { .sa_handler = sigterm_handler };
 583         sigaction(SIGTERM, &sa, NULL);
 584         sigaction(SIGINT, &sa, NULL);
 585
 586         sigemptyset(&term_sigs);
 587         sigaddset(&term_sigs, SIGTERM);
 588         sigaddset(&term_sigs, SIGINT);
 589         sigprocmask(SIG_BLOCK, &term_sigs, NULL);
 590
 591         int inited = 0;
 592         while (!want_shutdown) {
 593                 if (!find_device()) {
 594                         if (!inited) {
 595                                 inited = 1;
 596                                 log_error("Data logger not connected, waiting until it appears");
 597                         }
 598                         interruptible_msleep(30000);
 599                         continue;
 600                 }
 601                 log_info("Listening");
 602
 603                 time_t last_sync = 0;
 604                 time_t last_show = 0;
 605                 int want_stats = 0;
 606                 int want_sleep = 0;
 607                 data_point_counter = 0;
 608                 while (!want_shutdown) {
 609                         time_t now = time(NULL);
 610                         if (now > last_sync + 900) {
 611                                 log_info("Synchronizing data logger time");
 612                                 set_clock();
 613                                 last_sync = now;
 614                         }
 615                         if (want_stats && now > last_show + 300) {
 616                                 log_info("Stats: received %d data points", data_point_counter);
 617                                 data_point_counter = 0;
 618                                 last_show = now;
 619                         }
 620
 621                         byte req[64], reply[64];
 622                         memset(req, 0, sizeof(req));
 623                         req[0] = 3;
 624                         err = send_and_receive(req, reply);
 625                         if (err < 0)
 626                                 break;
 627                         want_sleep = 1;
 628                         if (err > 0 && parse_packet(reply))
 629                                 want_sleep = 0;
 630                         if (want_sleep) {
 631                                 interruptible_msleep(4000);
 632                                 want_stats = 1;
 633                         } else
 634                                 interruptible_msleep(5);
 635                 }
 636
 637                 log_info("Disconnecting data logger");
 638                 release_device();
 639                 inited = 0;
 640                 interruptible_msleep(10000);
 641         }
 642
 643         log_info("Terminated");
 644         return 0;
 645 }