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 rx_endpoint, tx_endpoint;
 304
 305 static int parse_descriptors(libusb_device *dev)
 306 {
 307         int err;
 308         struct libusb_config_descriptor *desc;
 309
 310         if (err = libusb_get_active_config_descriptor(dev, &desc)) {
 311                 log_error("libusb_get_config_descriptor failed: error %d", err);
 312                 return 0;
 313         }
 314         if (desc->bNumInterfaces != 1) {
 315                 log_error("Unexpected number of interfaces: %d", desc->bNumInterfaces);
 316                 goto failed;
 317         }
 318
 319         const struct libusb_interface *iface = &desc->interface[0];
 320         if (iface->num_altsetting != 1) {
 321                 log_error("Unexpected number of alternate interface settings: %d", iface->num_altsetting);
 322                 goto failed;
 323         }
 324
 325         const struct libusb_interface_descriptor *ifd = &iface->altsetting[0];
 326         if (ifd->bNumEndpoints != 2) {
 327                 log_error("Unexpected number of endpoints: %d", ifd->bNumEndpoints);
 328                 goto failed;
 329         }
 330
 331         rx_endpoint = tx_endpoint = -1;
 332         for (int i=0; i<2; i++) {
 333                 const struct libusb_endpoint_descriptor *epd = &ifd->endpoint[i];
 334                 if (epd->bEndpointAddress & 0x80)
 335                         rx_endpoint = epd->bEndpointAddress;
 336                 else
 337                         tx_endpoint = epd->bEndpointAddress;
 338         }
 339         if (rx_endpoint < 0 || tx_endpoint < 0) {
 340                 log_error("Failed to identify endpoints");
 341                 goto failed;
 342         }
 343
 344         log_pkt("Found endpoints: rx==%02x tx=%02x\n", rx_endpoint, tx_endpoint);
 345         libusb_free_config_descriptor(desc);
 346         return 1;
 347
 348 failed:
 349         libusb_free_config_descriptor(desc);
 350         return 0;
 351 }
 352
 353 static int find_device(void)
 354 {
 355         libusb_device **devlist;
 356         ssize_t devn = libusb_get_device_list(usb_ctxt, &devlist);
 357         if (devn < 0) {
 358                 log_error("Cannot enumerate USB devices: error %d", (int) devn);
 359                 return 0;
 360         }
 361
 362         for (ssize_t i=0; i<devn; i++) {
 363                 struct libusb_device_descriptor desc;
 364                 libusb_device *dev = devlist[i];
 365                 if (!libusb_get_device_descriptor(dev, &desc)) {
 366                         if (desc.idVendor == 0x0451 && desc.idProduct == 0x3211) {
 367                                 log_info("Arexx data logger found at usb%d.%d", libusb_get_bus_number(dev), libusb_get_device_address(dev));
 368                                 if (!parse_descriptors(dev))
 369                                         continue;
 370                                 int err;
 371                                 if (err = libusb_open(dev, &devh)) {
 372                                         log_error("libusb_open() failed: error %d", err);
 373                                         goto failed;
 374                                 }
 375                                 if (err = libusb_claim_interface(devh, 0)) {
 376                                         log_error("libusb_claim_interface() failed: error %d", err);
 377                                         libusb_close(devh);
 378                                         goto failed;
 379                                 }
 380                                 libusb_free_device_list(devlist, 1);
 381                                 return 1;
 382                         }
 383                 }
 384         }
 385
 386 failed:
 387         libusb_free_device_list(devlist, 1);
 388         return 0;
 389 }
 390
 391 static void release_device(void)
 392 {
 393         libusb_release_interface(devh, 0);
 394         libusb_reset_device(devh);
 395         libusb_close(devh);
 396         devh = NULL;
 397 }
 398
 399 static void dump_packet(byte *pkt)
 400 {
 401         for (int i=0; i<64; i++) {
 402                 if (!(i % 16))
 403                         log_pkt("\t%02x:", i);
 404                 log_pkt(" %02x", pkt[i]);
 405                 if (i % 16 == 15)
 406                         log_pkt("\n");
 407         }
 408 }
 409
 410 static int send_and_receive(byte *req, byte *reply)
 411 {
 412         if (debug_packets) {
 413                 time_t t = time(NULL);
 414                 struct tm tm;
 415                 localtime_r(&t, &tm);
 416
 417                 char tbuf[64];
 418                 strftime(tbuf, sizeof(tbuf), "%Y-%m-%d %H:%M:%S", &tm);
 419                 log_pkt("## %s\n", tbuf);
 420         }
 421
 422         int err, transferred;
 423         if (err = libusb_bulk_transfer(devh, tx_endpoint, req, 64, &transferred, 200)) {
 424                 if (err == LIBUSB_ERROR_TIMEOUT) {
 425                         log_pkt(">> xmit timed out\n");
 426                         return 0;
 427                 }
 428                 log_pkt(">> xmit error %d\n", err);
 429                 log_error("Transmit error: %d", err);
 430                 return err;
 431         }
 432         if (debug_packets) {
 433                 log_pkt(">> xmit %d bytes\n", transferred);
 434                 dump_packet(req);
 435         }
 436         if (err = libusb_bulk_transfer(devh, rx_endpoint, reply, 64, &transferred, 200)) {
 437                 if (err == LIBUSB_ERROR_TIMEOUT) {
 438                         log_pkt("<< recv timed out\n");
 439                         return 0;
 440                 }
 441                 log_pkt("<< recv error %d\n", err);
 442                 log_error("Receive error: %d", err);
 443                 return err;
 444         }
 445         if (debug_packets)
 446                 log_pkt("<< recv %d bytes\n", transferred);
 447         while (transferred < 64)
 448                 reply[transferred++] = 0xff;
 449         if (debug_packets)
 450                 dump_packet(reply);
 451         return 1;
 452 }
 453
 454 static unsigned int get_be16(byte *p)
 455 {
 456         return p[1] | (p[0] << 8);
 457 }
 458
 459 static unsigned int get_le16(byte *p)
 460 {
 461         return p[0] | (p[1] << 8);
 462 }
 463
 464 static unsigned int get_le32(byte *p)
 465 {
 466         return get_le16(p) | (get_le16(p+2) << 16);
 467 }
 468
 469 static void put_le16(byte *p, unsigned int x)
 470 {
 471         p[0] = x;
 472         p[1] = x >> 8;
 473 }
 474
 475 static void put_le32(byte *p, unsigned int x)
 476 {
 477         put_le16(p, x);
 478         put_le16(p+2, x>>16);
 479 }
 480
 481 static int parse_packet(byte *reply)
 482 {
 483         if (reply[0]) {
 484                 log_error("Unknown packet type %02x", reply[0]);
 485                 return 0;
 486         }
 487
 488         int pos = 1;
 489         int points = 0;
 490         while (pos < 64) {
 491                 byte *p = reply + pos;
 492                 int len = p[0];
 493                 if (!len || len == 0xff)
 494                         break;
 495                 if (len < 9 || len > 10) {
 496                         log_error("Unknown tuple length %02x", len);
 497                         break;
 498                 }
 499                 if (pos + len > 64) {
 500                         log_error("Tuple truncated");
 501                         break;
 502                 }
 503                 int id = get_le16(p+1);
 504                 int raw = get_be16(p+3);
 505                 int t = get_le32(p+5);
 506                 int q = (len > 9) ? p[9] : -1;
 507                 if (debug_raw_data) {
 508                         printf("... %02x: id=%d raw=%d t=%d", len, id, raw, t);
 509                         if (len > 9)
 510                                 printf(" q=%d", q);
 511                         printf("\n");
 512                 }
 513                 raw_point(t, id, raw, q);
 514                 pos += len;
 515                 points++;
 516         }
 517
 518         return points;
 519 }
 520
 521 static void set_clock(void)
 522 {
 523         byte req[64], reply[64];
 524         memset(req, 0, 64);
 525         req[0] = 4;
 526         time_t t = time(NULL);
 527         put_le32(req+1, t-TIME_OFFSET);
 528         send_and_receive(req, reply);
 529
 530 #if 0
 531         /*
 532          *  Original software also sends a packet with type 3 and the timestamp,
 533          *  but it does not make any sense, especially as they ignore the sensor
 534          *  readings in the answer.
 535          */
 536         req[0] = 3;
 537         send_and_receive(req, reply);
 538         parse_packet(reply);
 539 #endif
 540 }
 541
 542 /*** Main ***/
 543
 544 static sigset_t term_sigs;
 545 static volatile sig_atomic_t want_shutdown;
 546
 547 static void sigterm_handler(int sig __attribute__((unused)))
 548 {
 549         want_shutdown = 1;
 550 }
 551
 552 static void interruptible_msleep(int ms)
 553 {
 554         sigprocmask(SIG_UNBLOCK, &term_sigs, NULL);
 555         struct timespec ts = { .tv_sec = ms/1000, .tv_nsec = (ms%1000) * 1000000 };
 556         nanosleep(&ts, NULL);
 557         sigprocmask(SIG_BLOCK, &term_sigs, NULL);
 558 }
 559
 560 static const struct option long_options[] = {
 561         { "debug",              0, NULL, 'd' },
 562         { "log-dir",            1, NULL, 'l' },
 563         { "debug-packets",      0, NULL, 'p' },
 564         { "debug-raw",          0, NULL, 'r' },
 565         { NULL,                 0, NULL, 0 },
 566 };
 567
 568 static void usage(void)
 569 {
 570         fprintf(stderr, "\n\
 571 Usage: arexxd <options>\n\
 572 \n\
 573 Options:\n\
 574 -d, --debug             Debug mode (no chdir, no fork, no syslog)\n\
 575 -l, --log-dir=<dir>     Directory where all received data should be stored\n\
 576 -p, --debug-packets     Log all packets sent and received\n\
 577 -r, --debug-raw         Log conversion from raw values\n\
 578 -u, --debug-usb         Enable libusb debug messages (to stdout/stderr)\n\
 579 ");
 580         exit(1);
 581 }
 582
 583 int main(int argc, char **argv)
 584 {
 585         int opt;
 586         while ((opt = getopt_long(argc, argv, "dl:pru", long_options, NULL)) >= 0)
 587                 switch (opt) {
 588                         case 'd':
 589                                 debug_mode++;
 590                                 break;
 591                         case 'l':
 592                                 log_dir = optarg;
 593                                 break;
 594                         case 'p':
 595                                 debug_packets++;
 596                                 break;
 597                         case 'r':
 598                                 debug_raw_data++;
 599                                 break;
 600                         case 'u':
 601                                 debug_usb++;
 602                                 break;
 603                         default:
 604                                 usage();
 605                 }
 606         if (optind < argc)
 607                 usage();
 608
 609         int err;
 610         if (err = libusb_init(&usb_ctxt))
 611                 die("Cannot initialize libusb: error %d", err);
 612         if (debug_usb)
 613                 libusb_set_debug(usb_ctxt, 3);
 614
 615         if (!debug_mode) {
 616                 if (chdir(log_dir) < 0)
 617                         die("Cannot change directory to %s: %m", log_dir);
 618                 if (debug_packets || debug_raw_data) {
 619                         close(1);
 620                         if (open("debug", O_WRONLY | O_CREAT | O_APPEND, 0666) < 0)
 621                                 die("Cannot open debug log: %m");
 622                         setlinebuf(stdout);
 623                 }
 624                 openlog("arexxd", LOG_NDELAY, LOG_DAEMON);
 625                 pid_t pid = fork();
 626                 if (pid < 0)
 627                         die("fork() failed: %m");
 628                 if (pid)
 629                         return 0;
 630                 setsid();
 631                 use_syslog = 1;
 632         }
 633
 634         struct sigaction sa = { .sa_handler = sigterm_handler };
 635         sigaction(SIGTERM, &sa, NULL);
 636         sigaction(SIGINT, &sa, NULL);
 637
 638         sigemptyset(&term_sigs);
 639         sigaddset(&term_sigs, SIGTERM);
 640         sigaddset(&term_sigs, SIGINT);
 641         sigprocmask(SIG_BLOCK, &term_sigs, NULL);
 642
 643         int inited = 0;
 644         while (!want_shutdown) {
 645                 if (!find_device()) {
 646                         if (!inited) {
 647                                 inited = 1;
 648                                 log_error("Data logger not connected, waiting until it appears");
 649                         }
 650                         interruptible_msleep(30000);
 651                         continue;
 652                 }
 653                 log_info("Listening");
 654
 655                 time_t last_sync = 0;
 656                 time_t last_show = 0;
 657                 int want_stats = 0;
 658                 int want_sleep = 0;
 659                 data_point_counter = 0;
 660                 while (!want_shutdown) {
 661                         time_t now = time(NULL);
 662                         if (now > last_sync + 900) {
 663                                 log_info("Synchronizing data logger time");
 664                                 set_clock();
 665                                 last_sync = now;
 666                         }
 667                         if (want_stats && now > last_show + 300) {
 668                                 log_info("Stats: received %d data points", data_point_counter);
 669                                 data_point_counter = 0;
 670                                 last_show = now;
 671                         }
 672
 673                         byte req[64], reply[64];
 674                         memset(req, 0, sizeof(req));
 675                         req[0] = 3;
 676                         err = send_and_receive(req, reply);
 677                         if (err < 0)
 678                                 break;
 679                         want_sleep = 1;
 680                         if (err > 0 && parse_packet(reply))
 681                                 want_sleep = 0;
 682                         if (want_sleep) {
 683                                 interruptible_msleep(4000);
 684                                 want_stats = 1;
 685                         } else
 686                                 interruptible_msleep(5);
 687                 }
 688
 689                 log_info("Disconnecting data logger");
 690                 release_device();
 691                 inited = 0;
 692                 interruptible_msleep(10000);
 693         }
 694
 695         log_info("Terminated");
 696         return 0;
 697 }