src/visomat-data-downloader.c

   1 /*
   2  * visomat-data-downloader - download data from Visomat Double Comfort
   3  *
   4  * The Visomat Double Comfort is a blood pressure meter with a USB port.
   5  *
   6  * Copyright (C) 2013  Antonio Ospite <ospite@studenti.unina.it>
   7  *
   8  * This program is free software: you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation, either version 3 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  20  */
  21
  22 #include <stdio.h>
  23 #include <stdbool.h>
  24 #include <stdlib.h>
  25 #include <string.h>
  26 #include <errno.h>
  27 #include <unistd.h>
  28 #include <libusb.h>
  29
  30 #ifdef DEBUG
  31 #define debug(...) fprintf(stderr, __VA_ARGS__)
  32 static void debug_dump_buffer(const char *filename, uint8_t *buffer, unsigned int len)
  33 {
  34         FILE *dump_file;
  35
  36         dump_file = fopen(filename, "wb");
  37         if (dump_file == NULL) {
  38                 fprintf(stderr, "Failed to open %s: %s\n", filename, strerror(errno));
  39                 return;
  40         }
  41
  42         fwrite(buffer, 1, len, dump_file);
  43         fclose(dump_file);
  44 }
  45 #else
  46 #define debug(...) do {} while(0)
  47 static void debug_dump_buffer(const char *filename, uint8_t *buffer, unsigned int len)
  48 {
  49         (void)filename;
  50         (void)buffer;
  51         (void)len;
  52 }
  53 #endif
  54
  55 #define VISOMAT_DEVICE_VID    0x1247
  56 #define VISOMAT_DEVICE_PID    0x00f8
  57 #define VISOMAT_CONFIGURATION 1
  58 #define VISOMAT_INTERFACE     1
  59 #define VISOMAT_EP_IN         0x82
  60 #define VISOMAT_EP_OUT        0x03
  61 #define VISOMAT_PACKET_SIZE   64
  62
  63 #define STX 0x02
  64 #define ETX 0x03
  65
  66 #define BASE_YEAR 2000
  67
  68 typedef enum {
  69         VISOMAT_CMD_DUMP_EEPROM,
  70         VISOMAT_CMD_UNKNOWN1, /* maybe the firmware revision */
  71         VISOMAT_CMD_GET_DATETIME,
  72         VISOMAT_CMD_START_MEASURE1,
  73         VISOMAT_CMD_UNKNOWN2, /* XXX transmission hangs */
  74         VISOMAT_CMD_UNKNOWN3,
  75 } visomat_command;
  76
  77 static char command_codes[][3] = {
  78         [VISOMAT_CMD_DUMP_EEPROM]    = "R00",
  79         [VISOMAT_CMD_UNKNOWN1]       = "R01",
  80         [VISOMAT_CMD_GET_DATETIME]   = "R02",
  81         [VISOMAT_CMD_START_MEASURE1] = "R03",
  82         [VISOMAT_CMD_UNKNOWN2]       = "R04",
  83         [VISOMAT_CMD_UNKNOWN3]       = "R05",
  84 };
  85
  86 struct datetime  {
  87         unsigned int year;
  88         unsigned int month;
  89         unsigned int day;
  90         unsigned int hour;
  91         unsigned int minute;
  92 };
  93
  94 struct pressure  {
  95         unsigned int flag; /* XXX Maybe this means arrhythmia? */
  96         unsigned int systolic;
  97         unsigned int diastolic;
  98         unsigned int pulses;
  99 };
 100
 101 static inline int extract_datetime(uint8_t *buffer, struct datetime *d)
 102 {
 103         int ret;
 104
 105         ret = sscanf((char *)buffer, "%02u%02u%02u%02u%02u",
 106                      &d->year,
 107                      &d->month,
 108                      &d->day,
 109                      &d->hour,
 110                      &d->minute);
 111         if (ret != 5)
 112                 return -EINVAL;
 113
 114         d->year += BASE_YEAR;
 115
 116         return 0;
 117 }
 118
 119 /*
 120  * NOTE: the CSV output is meant to be compatible with one from the Windows
 121  * program, which uses the %d/%m/%Y date format, so that's not my fault.
 122  */
 123 static void print_record_csv_compat(struct datetime *d, struct pressure *p)
 124 {
 125         unsigned int pulse_pressure;
 126
 127         printf("%02u/%02u/%04u;%02u.%02u;",
 128                d->day, d->month, d->year, d->hour, d->minute);
 129
 130         printf("%u;%u;%u;", p->systolic, p->diastolic, p->pulses);
 131
 132         pulse_pressure = p->systolic - p->diastolic;
 133         printf("%u;", pulse_pressure);
 134
 135         if (p->flag)
 136                 printf("x");
 137
 138 #if 0
 139         /* The original software does not seem to be doing that */
 140         if (p->pulses > 100)
 141                 printf("tachycardia");
 142         else if (p->pulses < 60)
 143                 printf("bradycardia");
 144 #endif
 145
 146         printf("\n");
 147 }
 148
 149 /* TODO: it would be better to separate decoding data from printing it */
 150 static int decode_eeprom(uint8_t *buffer,
 151                          unsigned int len,
 152                          unsigned int user_mask)
 153 {
 154         int ret;
 155         unsigned int n;
 156         unsigned int i;
 157         unsigned int j;
 158         unsigned int user_id;
 159         unsigned int num_records;
 160         struct datetime d;
 161         struct pressure p;
 162
 163         if (buffer[0] != STX || buffer[1] != 'M') {
 164                 fprintf(stderr, "Usupported data.\n");
 165                 return -EINVAL;
 166         }
 167
 168         if (buffer[len - 1] != ETX) {
 169                 fprintf(stderr, "Bad terminator in data. Buffer too small?\n");
 170                 return -EINVAL;
 171         }
 172
 173         /* skip the initial STX */
 174         i = 1;
 175
 176         /* and the final ETX */
 177         n = len - 1;
 178
 179         while (i < n) {
 180                 /* Each user record begins with 'M', maybe for "Memory" */
 181                 if (buffer[i] == 'M') {
 182                         /* i tracks the bytes consumed */
 183                         i += 1;
 184
 185                         ret = sscanf((char *)(buffer + i), "%1u%02u",
 186                                      &user_id, &num_records);
 187                         if (ret != 2)
 188                                 return -EINVAL;
 189
 190                         /* user_id and num_records take 3 bytes */
 191                         i += 3;
 192
 193                         /*
 194                          * when there are no records, there is a dummy byte
 195                          * which has to be consumed
 196                          */
 197                         if (num_records == 0)
 198                                 i += 1;
 199
 200                         for (j = 0; j < num_records; j++) {
 201                                 ret = extract_datetime(buffer + i, &d);
 202                                 if (ret < 0)
 203                                         return ret;
 204
 205                                 /* datetime takes 10 bytes */
 206                                 i += 10;
 207
 208                                 ret = sscanf((char *)(buffer + i),
 209                                              "%1u%03u%03u%03u",
 210                                              &p.flag,
 211                                              &p.systolic,
 212                                              &p.diastolic,
 213                                              &p.pulses);
 214                                 if (ret != 4)
 215                                         return -EINVAL;
 216
 217                                 /* pressure data is 10 bytes */
 218                                 i += 10;
 219
 220                                 /* TODO: split out the printing part */
 221                                 if (user_id & user_mask) {
 222                                         if (j == 0)
 223                                                 printf("# User: %d\n", user_id);
 224                                         print_record_csv_compat(&d, &p);
 225                                 }
 226                         }
 227                 }
 228         }
 229
 230         return 0;
 231 }
 232
 233 static int decode_datetime(uint8_t *buffer, unsigned int len)
 234 {
 235         int ret;
 236         uint8_t code[4] = { 0 };
 237         struct datetime d;
 238         uint8_t *pbuffer = buffer;
 239
 240         if (len != 15)
 241                 return -EINVAL;
 242
 243         code[0] = buffer[1];
 244         code[1] = buffer[2];
 245         code[2] = buffer[3];
 246
 247         ret = extract_datetime(pbuffer + 4, &d);
 248         if (ret < 0)
 249                 return ret;
 250
 251         printf("# (%s) Date: %04d/%02d/%02d %02d:%02d\n",
 252                code, d.year, d.month, d.day, d.hour, d.minute);
 253
 254         return 0;
 255 }
 256
 257 static int send_command(libusb_device_handle *dev, visomat_command cmd)
 258 {
 259         int ret;
 260         int transferred;
 261         uint8_t request[5];
 262
 263         request[0] = STX;
 264         request[1] = command_codes[cmd][0];
 265         request[2] = command_codes[cmd][1];
 266         request[3] = command_codes[cmd][2];
 267         request[4] = ETX;
 268
 269         transferred = 0;
 270         ret = libusb_bulk_transfer(dev, VISOMAT_EP_OUT, request, sizeof(request), &transferred, 0);
 271         if (ret != 0 || transferred != sizeof(request)) {
 272                 fprintf(stderr, "Error: sending request: %d (%s)\ttransferred: %d (expected %zu)\n",
 273                         ret, libusb_error_name(ret), transferred, sizeof(request));
 274                 return ret;
 275         }
 276         return 0;
 277 }
 278
 279 static int get_response(libusb_device_handle *dev,
 280                         uint8_t *buffer,
 281                         unsigned int len)
 282 {
 283         int ret;
 284         int transferred;
 285         uint8_t response[VISOMAT_PACKET_SIZE] = { 0 };
 286         unsigned int i;
 287
 288         i = 0;
 289         do {
 290                 unsigned int j;
 291
 292                 transferred = 0;
 293                 ret = libusb_bulk_transfer(dev, VISOMAT_EP_IN, response, sizeof(response), &transferred, 5000);
 294                 if (ret != 0) {
 295                         fprintf(stderr, "Error getting response: %d (%s)\ttransferred: %d (expected %zu)\n",
 296                                 ret, libusb_error_name(ret), transferred, sizeof(response));
 297                         return ret;
 298                 }
 299
 300                 for (j = 0; j < (unsigned int)transferred; j++) {
 301                         buffer[i] = response[j];
 302                         i += 1;
 303                 }
 304
 305         } while (buffer[i - 1] != ETX && i < len);
 306
 307         /* Check if the buffer contains a valid response packet */
 308         if (buffer[0] != STX || buffer[i - 1] != ETX)
 309                 return -EINVAL;
 310
 311         return i;
 312 }
 313
 314 /* Candidates for a future public API, if a shared library will ever be made */
 315 #define visomat_device libusb_device_handle
 316 static int visomat_dump_eeprom(visomat_device *dev, unsigned int user_mask)
 317 {
 318         /* Assuming an EEPROM of 4 KiB  */
 319         uint8_t buffer[4096] = { 0 };
 320         int ret;
 321
 322         ret = send_command(dev, VISOMAT_CMD_DUMP_EEPROM);
 323         if (ret < 0)
 324                 return ret;
 325
 326         ret = get_response(dev, buffer, sizeof(buffer));
 327         debug("buffer size: %d\n", ret);
 328         debug_dump_buffer("eeprom.bin", buffer, sizeof(buffer));
 329         if (ret < 0)
 330                 return ret;
 331
 332         ret = decode_eeprom(buffer, ret, user_mask);
 333         if (ret < 0)
 334                 return ret;
 335
 336         return 0;
 337 }
 338
 339 static int visomat_get_datetime(visomat_device *dev)
 340 {
 341         uint8_t buffer[255] = { 0 };
 342         int ret;
 343
 344         ret = send_command(dev, VISOMAT_CMD_GET_DATETIME);
 345         if (ret < 0)
 346                 return ret;
 347
 348         ret = get_response(dev, buffer, sizeof(buffer));
 349         if (ret < 0)
 350                 return ret;
 351
 352         ret = decode_datetime(buffer, ret);
 353         if (ret < 0)
 354                 return ret;
 355
 356         return 0;
 357 }
 358
 359 static void usage(const char *name)
 360 {
 361         printf("usage: %s [OPTIONS]\n\n", name);
 362         printf("OPTIONS:\n");
 363         printf("\t-D\t\tenable libusb debug output\n");
 364         printf("\t-h\t\tthis help message\n");
 365 }
 366
 367 int main(int argc, char *argv[])
 368 {
 369         int ret;
 370         int opt;
 371         bool enable_libusb_debug = false;
 372         libusb_device_handle *dev;
 373         int current_configuration;
 374
 375         while ((opt = getopt(argc, argv, "Dh")) != -1) {
 376                 switch (opt) {
 377                 case 'D':
 378                         enable_libusb_debug = true;
 379                         break;
 380                 case 'h':
 381                         usage(argv[0]);
 382                         ret = 0;
 383                         goto out;
 384                 default: /* '?' */
 385                         usage(argv[0]);
 386                         ret = -EINVAL;
 387                         goto out;
 388                 }
 389         }
 390
 391         ret = libusb_init(NULL);
 392         if (ret < 0) {
 393                 fprintf(stderr, "libusb_init failed: %s\n",
 394                         libusb_error_name(ret));
 395                 goto out;
 396         }
 397
 398         libusb_set_debug(NULL, enable_libusb_debug ?
 399                          LIBUSB_LOG_LEVEL_DEBUG : LIBUSB_LOG_LEVEL_INFO);
 400
 401         dev = libusb_open_device_with_vid_pid(NULL,
 402                                               VISOMAT_DEVICE_VID,
 403                                               VISOMAT_DEVICE_PID);
 404         if (dev == NULL) {
 405                 fprintf(stderr, "libusb_open failed: %s\n", strerror(errno));
 406                 ret = -errno;
 407                 goto out_libusb_exit;
 408         }
 409
 410         current_configuration = -1;
 411         ret = libusb_get_configuration(dev, &current_configuration);
 412         if (ret < 0) {
 413                 fprintf(stderr, "libusb_get_configuration failed: %s\n",
 414                         libusb_error_name(ret));
 415                 goto out_libusb_close;
 416         }
 417
 418         if (current_configuration != VISOMAT_CONFIGURATION) {
 419                 ret = libusb_set_configuration(dev, VISOMAT_CONFIGURATION);
 420                 if (ret < 0) {
 421                         fprintf(stderr, "libusb_set_configuration failed: %s\n",
 422                                 libusb_error_name(ret));
 423                         fprintf(stderr, "Cannot set configuration %d\n",
 424                                 VISOMAT_CONFIGURATION);
 425                         goto out_libusb_close;
 426                 }
 427         }
 428
 429         libusb_set_auto_detach_kernel_driver(dev, 1);
 430
 431         ret = libusb_claim_interface(dev, VISOMAT_INTERFACE);
 432         if (ret < 0) {
 433                 fprintf(stderr, "libusb_claim_interface failed: %s\n",
 434                         libusb_error_name(ret));
 435                 fprintf(stderr, "Cannot claim interface %d\n",
 436                         VISOMAT_INTERFACE);
 437                 goto out_libusb_close;
 438         }
 439
 440         /* Checking that the configuration has not changed, as suggested in
 441          * http://libusb.sourceforge.net/api-1.0/caveats.html
 442          */
 443         current_configuration = -1;
 444         ret = libusb_get_configuration(dev, &current_configuration);
 445         if (ret < 0) {
 446                 fprintf(stderr, "libusb_get_configuration after claim failed: %s\n",
 447                         libusb_error_name(ret));
 448                 goto out_libusb_release_interface;
 449         }
 450
 451         if (current_configuration != VISOMAT_CONFIGURATION) {
 452                 fprintf(stderr, "libusb configuration changed (expected: %d, current: %d)\n",
 453                         VISOMAT_CONFIGURATION, current_configuration);
 454                 ret = -EINVAL;
 455                 goto out_libusb_release_interface;
 456         }
 457
 458         ret = visomat_get_datetime(dev);
 459         if (ret < 0)
 460                 goto out_libusb_release_interface;
 461
 462         ret = visomat_dump_eeprom(dev, 0x01 | 0x02);
 463         if (ret < 0)
 464                 goto out_libusb_release_interface;
 465
 466 out_libusb_release_interface:
 467         libusb_release_interface(dev, VISOMAT_INTERFACE);
 468 out_libusb_close:
 469         libusb_close(dev);
 470         dev = NULL;
 471 out_libusb_exit:
 472         libusb_exit(NULL);
 473 out:
 474         return ret;
 475 }