lib/lws-plat-unix.c

   1 #include "private-libwebsockets.h"
   2
   3 #include <pwd.h>
   4 #include <grp.h>
   5
   6 #include <dlfcn.h>
   7 #include <dirent.h>
   8
   9
  10 /*
  11  * included from libwebsockets.c for unix builds
  12  */
  13
  14 unsigned long long time_in_microseconds(void)
  15 {
  16         struct timeval tv;
  17         gettimeofday(&tv, NULL);
  18         return ((unsigned long long)tv.tv_sec * 1000000LL) + tv.tv_usec;
  19 }
  20
  21 LWS_VISIBLE int
  22 lws_get_random(struct lws_context *context, void *buf, int len)
  23 {
  24         return read(context->fd_random, (char *)buf, len);
  25 }
  26
  27 LWS_VISIBLE int
  28 lws_send_pipe_choked(struct lws *wsi)
  29 {
  30         struct lws_pollfd fds;
  31
  32         /* treat the fact we got a truncated send pending as if we're choked */
  33         if (wsi->trunc_len)
  34                 return 1;
  35
  36         fds.fd = wsi->sock;
  37         fds.events = POLLOUT;
  38         fds.revents = 0;
  39
  40         if (poll(&fds, 1, 0) != 1)
  41                 return 1;
  42
  43         if ((fds.revents & POLLOUT) == 0)
  44                 return 1;
  45
  46         /* okay to send another packet without blocking */
  47
  48         return 0;
  49 }
  50
  51 LWS_VISIBLE int
  52 lws_poll_listen_fd(struct lws_pollfd *fd)
  53 {
  54         return poll(fd, 1, 0);
  55 }
  56
  57 /*
  58  * This is just used to interrupt poll waiting
  59  * we don't have to do anything with it.
  60  */
  61 static void
  62 lws_sigusr2(int sig)
  63 {
  64 }
  65
  66 /**
  67  * lws_cancel_service_pt() - Cancel servicing of pending socket activity
  68  *                              on one thread
  69  * @wsi:        Cancel service on the thread this wsi is serviced by
  70  *
  71  *      This function let a call to lws_service() waiting for a timeout
  72  *      immediately return.
  73  */
  74 LWS_VISIBLE void
  75 lws_cancel_service_pt(struct lws *wsi)
  76 {
  77         struct lws_context_per_thread *pt = &wsi->context->pt[(int)wsi->tsi];
  78         char buf = 0;
  79
  80         if (write(pt->dummy_pipe_fds[1], &buf, sizeof(buf)) != 1)
  81                 lwsl_err("Cannot write to dummy pipe");
  82 }
  83
  84 /**
  85  * lws_cancel_service() - Cancel ALL servicing of pending socket activity
  86  * @context:    Websocket context
  87  *
  88  *      This function let a call to lws_service() waiting for a timeout
  89  *      immediately return.
  90  */
  91 LWS_VISIBLE void
  92 lws_cancel_service(struct lws_context *context)
  93 {
  94         struct lws_context_per_thread *pt = &context->pt[0];
  95         char buf = 0, m = context->count_threads;
  96
  97         while (m--) {
  98                 if (write(pt->dummy_pipe_fds[1], &buf, sizeof(buf)) != 1)
  99                         lwsl_err("Cannot write to dummy pipe");
 100                 pt++;
 101         }
 102 }
 103
 104 LWS_VISIBLE void lwsl_emit_syslog(int level, const char *line)
 105 {
 106         int syslog_level = LOG_DEBUG;
 107
 108         switch (level) {
 109         case LLL_ERR:
 110                 syslog_level = LOG_ERR;
 111                 break;
 112         case LLL_WARN:
 113                 syslog_level = LOG_WARNING;
 114                 break;
 115         case LLL_NOTICE:
 116                 syslog_level = LOG_NOTICE;
 117                 break;
 118         case LLL_INFO:
 119                 syslog_level = LOG_INFO;
 120                 break;
 121         }
 122         syslog(syslog_level, "%s", line);
 123 }
 124
 125 LWS_VISIBLE int
 126 lws_plat_service_tsi(struct lws_context *context, int timeout_ms, int tsi)
 127 {
 128         struct lws_context_per_thread *pt = &context->pt[tsi];
 129         int n = -1, m, c;
 130         char buf;
 131
 132         /* stay dead once we are dead */
 133
 134         if (!context || !context->vhost_list)
 135                 return 1;
 136
 137         if (timeout_ms < 0)
 138                 goto faked_service;
 139
 140         lws_libev_run(context, tsi);
 141         lws_libuv_run(context, tsi);
 142
 143         if (!context->service_tid_detected) {
 144                 struct lws _lws;
 145
 146                 memset(&_lws, 0, sizeof(_lws));
 147                 _lws.context = context;
 148
 149                 context->service_tid_detected =
 150                         context->vhost_list->protocols[0].callback(
 151                         &_lws, LWS_CALLBACK_GET_THREAD_ID, NULL, NULL, 0);
 152         }
 153         context->service_tid = context->service_tid_detected;
 154
 155         timeout_ms = lws_service_adjust_timeout(context, timeout_ms, tsi);
 156
 157         n = poll(pt->fds, pt->fds_count, timeout_ms);
 158
 159 #ifdef LWS_OPENSSL_SUPPORT
 160         if (!pt->rx_draining_ext_list &&
 161             !lws_ssl_anybody_has_buffered_read_tsi(context, tsi) && !n) {
 162 #else
 163         if (!pt->rx_draining_ext_list && !n) /* poll timeout */ {
 164 #endif
 165                 lws_service_fd_tsi(context, NULL, tsi);
 166                 return 0;
 167         }
 168
 169 faked_service:
 170         m = lws_service_flag_pending(context, tsi);
 171         if (m)
 172                 c = -1; /* unknown limit */
 173         else
 174                 if (n < 0) {
 175                         if (LWS_ERRNO != LWS_EINTR)
 176                                 return -1;
 177                         return 0;
 178                 } else
 179                         c = n;
 180
 181         /* any socket with events to service? */
 182         for (n = 0; n < pt->fds_count && c; n++) {
 183                 if (!pt->fds[n].revents)
 184                         continue;
 185
 186                 c--;
 187
 188                 if (pt->fds[n].fd == pt->dummy_pipe_fds[0]) {
 189                         if (read(pt->fds[n].fd, &buf, 1) != 1)
 190                                 lwsl_err("Cannot read from dummy pipe.");
 191                         continue;
 192                 }
 193
 194                 m = lws_service_fd_tsi(context, &pt->fds[n], tsi);
 195                 if (m < 0)
 196                         return -1;
 197                 /* if something closed, retry this slot */
 198                 if (m)
 199                         n--;
 200         }
 201
 202         return 0;
 203 }
 204
 205 LWS_VISIBLE int
 206 lws_plat_service(struct lws_context *context, int timeout_ms)
 207 {
 208         return lws_plat_service_tsi(context, timeout_ms, 0);
 209 }
 210
 211 LWS_VISIBLE int
 212 lws_plat_set_socket_options(struct lws_vhost *vhost, int fd)
 213 {
 214         int optval = 1;
 215         socklen_t optlen = sizeof(optval);
 216
 217 #if defined(__APPLE__) || \
 218     defined(__FreeBSD__) || defined(__FreeBSD_kernel__) || \
 219     defined(__NetBSD__) || \
 220     defined(__OpenBSD__)
 221         struct protoent *tcp_proto;
 222 #endif
 223
 224         if (vhost->ka_time) {
 225                 /* enable keepalive on this socket */
 226                 optval = 1;
 227                 if (setsockopt(fd, SOL_SOCKET, SO_KEEPALIVE,
 228                                (const void *)&optval, optlen) < 0)
 229                         return 1;
 230
 231 #if defined(__APPLE__) || \
 232     defined(__FreeBSD__) || defined(__FreeBSD_kernel__) || \
 233     defined(__NetBSD__) || \
 234         defined(__CYGWIN__) || defined(__OpenBSD__)
 235
 236                 /*
 237                  * didn't find a way to set these per-socket, need to
 238                  * tune kernel systemwide values
 239                  */
 240 #else
 241                 /* set the keepalive conditions we want on it too */
 242                 optval = vhost->ka_time;
 243                 if (setsockopt(fd, IPPROTO_TCP, TCP_KEEPIDLE,
 244                                (const void *)&optval, optlen) < 0)
 245                         return 1;
 246
 247                 optval = vhost->ka_interval;
 248                 if (setsockopt(fd, IPPROTO_TCP, TCP_KEEPINTVL,
 249                                (const void *)&optval, optlen) < 0)
 250                         return 1;
 251
 252                 optval = vhost->ka_probes;
 253                 if (setsockopt(fd, IPPROTO_TCP, TCP_KEEPCNT,
 254                                (const void *)&optval, optlen) < 0)
 255                         return 1;
 256 #endif
 257         }
 258
 259         /* Disable Nagle */
 260         optval = 1;
 261 #if !defined(__APPLE__) && \
 262     !defined(__FreeBSD__) && !defined(__FreeBSD_kernel__) && \
 263     !defined(__NetBSD__) && \
 264     !defined(__OpenBSD__)
 265         if (setsockopt(fd, SOL_TCP, TCP_NODELAY, (const void *)&optval, optlen) < 0)
 266                 return 1;
 267 #else
 268         tcp_proto = getprotobyname("TCP");
 269         if (setsockopt(fd, tcp_proto->p_proto, TCP_NODELAY, &optval, optlen) < 0)
 270                 return 1;
 271 #endif
 272
 273         /* We are nonblocking... */
 274         if (fcntl(fd, F_SETFL, O_NONBLOCK) < 0)
 275                 return 1;
 276
 277         return 0;
 278 }
 279
 280 LWS_VISIBLE void
 281 lws_plat_drop_app_privileges(struct lws_context_creation_info *info)
 282 {
 283         if (info->gid != -1)
 284                 if (setgid(info->gid))
 285                         lwsl_warn("setgid: %s\n", strerror(LWS_ERRNO));
 286
 287         if (info->uid != -1) {
 288                 struct passwd *p = getpwuid(info->uid);
 289
 290                 if (p) {
 291                         initgroups(p->pw_name, info->gid);
 292                         if (setuid(info->uid))
 293                                 lwsl_warn("setuid: %s\n", strerror(LWS_ERRNO));
 294                         else
 295                                 lwsl_notice("Set privs to user '%s'\n", p->pw_name);
 296                 } else
 297                         lwsl_warn("getpwuid: unable to find uid %d", info->uid);
 298         }
 299 }
 300
 301 #ifdef LWS_WITH_PLUGINS
 302
 303 #if defined(LWS_USE_LIBUV) && UV_VERSION_MAJOR > 0
 304
 305 /* libuv.c implements these in a cross-platform way */
 306
 307 #else
 308
 309 static int filter(const struct dirent *ent)
 310 {
 311         if (!strcmp(ent->d_name, ".") || !strcmp(ent->d_name, ".."))
 312                 return 0;
 313
 314         return 1;
 315 }
 316
 317 LWS_VISIBLE int
 318 lws_plat_plugins_init(struct lws_context * context, const char *d)
 319 {
 320         struct lws_plugin_capability lcaps;
 321         struct lws_plugin *plugin;
 322         lws_plugin_init_func initfunc;
 323         struct dirent **namelist;
 324         int n, i, m, ret = 0;
 325         char path[256];
 326         void *l;
 327
 328
 329         n = scandir(d, &namelist, filter, alphasort);
 330         if (n < 0) {
 331                 lwsl_err("Scandir on %s failed\n", d);
 332                 return 1;
 333         }
 334
 335         lwsl_notice("  Plugins:\n");
 336
 337         for (i = 0; i < n; i++) {
 338                 if (strlen(namelist[i]->d_name) < 7)
 339                         goto inval;
 340
 341                 lwsl_notice("   %s\n", namelist[i]->d_name);
 342
 343                 snprintf(path, sizeof(path) - 1, "%s/%s", d,
 344                          namelist[i]->d_name);
 345                 l = dlopen(path, RTLD_NOW);
 346                 if (!l) {
 347                         lwsl_err("Error loading DSO: %s\n", dlerror());
 348                         while (i++ < n)
 349                                 free(namelist[i]);
 350                         goto bail;
 351                 }
 352                 /* we could open it, can we get his init function? */
 353                 m = snprintf(path, sizeof(path) - 1, "init_%s",
 354                              namelist[i]->d_name + 3 /* snip lib... */);
 355                 path[m - 3] = '\0'; /* snip the .so */
 356                 initfunc = dlsym(l, path);
 357                 if (!initfunc) {
 358                         lwsl_err("Failed to get init on %s: %s",
 359                                         namelist[i]->d_name, dlerror());
 360                         dlclose(l);
 361                 }
 362                 lcaps.api_magic = LWS_PLUGIN_API_MAGIC;
 363                 m = initfunc(context, &lcaps);
 364                 if (m) {
 365                         lwsl_err("Initializing %s failed %d\n",
 366                                 namelist[i]->d_name, m);
 367                         dlclose(l);
 368                         goto skip;
 369                 }
 370
 371                 plugin = lws_malloc(sizeof(*plugin));
 372                 if (!plugin) {
 373                         lwsl_err("OOM\n");
 374                         goto bail;
 375                 }
 376                 plugin->list = context->plugin_list;
 377                 context->plugin_list = plugin;
 378                 strncpy(plugin->name, namelist[i]->d_name, sizeof(plugin->name) - 1);
 379                 plugin->name[sizeof(plugin->name) - 1] = '\0';
 380                 plugin->l = l;
 381                 plugin->caps = lcaps;
 382                 context->plugin_protocol_count += lcaps.count_protocols;
 383                 context->plugin_extension_count += lcaps.count_extensions;
 384
 385                 free(namelist[i]);
 386                 continue;
 387
 388 skip:
 389                 dlclose(l);
 390 inval:
 391                 free(namelist[i]);
 392         }
 393
 394 bail:
 395         free(namelist);
 396
 397         return ret;
 398 }
 399
 400 LWS_VISIBLE int
 401 lws_plat_plugins_destroy(struct lws_context * context)
 402 {
 403         struct lws_plugin *plugin = context->plugin_list, *p;
 404         lws_plugin_destroy_func func;
 405         char path[256];
 406         int m;
 407
 408         if (!plugin)
 409                 return 0;
 410
 411         lwsl_notice("%s\n", __func__);
 412
 413         while (plugin) {
 414                 p = plugin;
 415                 m = snprintf(path, sizeof(path) - 1, "destroy_%s", plugin->name + 3);
 416                 path[m - 3] = '\0';
 417                 func = dlsym(plugin->l, path);
 418                 if (!func) {
 419                         lwsl_err("Failed to get destroy on %s: %s",
 420                                         plugin->name, dlerror());
 421                         goto next;
 422                 }
 423                 m = func(context);
 424                 if (m)
 425                         lwsl_err("Initializing %s failed %d\n",
 426                                 plugin->name, m);
 427 next:
 428                 dlclose(p->l);
 429                 plugin = p->list;
 430                 p->list = NULL;
 431                 free(p);
 432         }
 433
 434         context->plugin_list = NULL;
 435
 436         return 0;
 437 }
 438
 439 #endif
 440 #endif
 441
 442
 443 static void
 444 sigpipe_handler(int x)
 445 {
 446 }
 447
 448 LWS_VISIBLE int
 449 lws_plat_context_early_init(void)
 450 {
 451         sigset_t mask;
 452
 453         signal(SIGUSR2, lws_sigusr2);
 454         sigemptyset(&mask);
 455         sigaddset(&mask, SIGUSR2);
 456
 457         sigprocmask(SIG_BLOCK, &mask, NULL);
 458
 459         signal(SIGPIPE, sigpipe_handler);
 460
 461         return 0;
 462 }
 463
 464 LWS_VISIBLE void
 465 lws_plat_context_early_destroy(struct lws_context *context)
 466 {
 467 }
 468
 469 LWS_VISIBLE void
 470 lws_plat_context_late_destroy(struct lws_context *context)
 471 {
 472         struct lws_context_per_thread *pt = &context->pt[0];
 473         int m = context->count_threads;
 474
 475 #ifdef LWS_WITH_PLUGINS
 476         if (context->plugin_list)
 477                 lws_plat_plugins_destroy(context);
 478 #endif
 479
 480         if (context->lws_lookup)
 481                 lws_free(context->lws_lookup);
 482
 483         while (m--) {
 484                 close(pt->dummy_pipe_fds[0]);
 485                 close(pt->dummy_pipe_fds[1]);
 486                 pt++;
 487         }
 488         close(context->fd_random);
 489 }
 490
 491 /* cast a struct sockaddr_in6 * into addr for ipv6 */
 492
 493 LWS_VISIBLE int
 494 lws_interface_to_sa(int ipv6, const char *ifname, struct sockaddr_in *addr,
 495                     size_t addrlen)
 496 {
 497         int rc = -1;
 498
 499         struct ifaddrs *ifr;
 500         struct ifaddrs *ifc;
 501 #ifdef LWS_USE_IPV6
 502         struct sockaddr_in6 *addr6 = (struct sockaddr_in6 *)addr;
 503 #endif
 504
 505         getifaddrs(&ifr);
 506         for (ifc = ifr; ifc != NULL && rc; ifc = ifc->ifa_next) {
 507                 if (!ifc->ifa_addr)
 508                         continue;
 509
 510                 lwsl_info(" interface %s vs %s\n", ifc->ifa_name, ifname);
 511
 512                 if (strcmp(ifc->ifa_name, ifname))
 513                         continue;
 514
 515                 switch (ifc->ifa_addr->sa_family) {
 516                 case AF_INET:
 517 #ifdef LWS_USE_IPV6
 518                         if (ipv6) {
 519                                 /* map IPv4 to IPv6 */
 520                                 bzero((char *)&addr6->sin6_addr,
 521                                                 sizeof(struct in6_addr));
 522                                 addr6->sin6_addr.s6_addr[10] = 0xff;
 523                                 addr6->sin6_addr.s6_addr[11] = 0xff;
 524                                 memcpy(&addr6->sin6_addr.s6_addr[12],
 525                                         &((struct sockaddr_in *)ifc->ifa_addr)->sin_addr,
 526                                                         sizeof(struct in_addr));
 527                         } else
 528 #endif
 529                                 memcpy(addr,
 530                                         (struct sockaddr_in *)ifc->ifa_addr,
 531                                                     sizeof(struct sockaddr_in));
 532                         break;
 533 #ifdef LWS_USE_IPV6
 534                 case AF_INET6:
 535                         memcpy(&addr6->sin6_addr,
 536                           &((struct sockaddr_in6 *)ifc->ifa_addr)->sin6_addr,
 537                                                        sizeof(struct in6_addr));
 538                         break;
 539 #endif
 540                 default:
 541                         continue;
 542                 }
 543                 rc = 0;
 544         }
 545
 546         freeifaddrs(ifr);
 547
 548         if (rc == -1) {
 549                 /* check if bind to IP adddress */
 550 #ifdef LWS_USE_IPV6
 551                 if (inet_pton(AF_INET6, ifname, &addr6->sin6_addr) == 1)
 552                         rc = 0;
 553                 else
 554 #endif
 555                 if (inet_pton(AF_INET, ifname, &addr->sin_addr) == 1)
 556                         rc = 0;
 557         }
 558
 559         return rc;
 560 }
 561
 562 LWS_VISIBLE void
 563 lws_plat_insert_socket_into_fds(struct lws_context *context, struct lws *wsi)
 564 {
 565         struct lws_context_per_thread *pt = &context->pt[(int)wsi->tsi];
 566
 567         lws_libev_io(wsi, LWS_EV_START | LWS_EV_READ);
 568         lws_libuv_io(wsi, LWS_EV_START | LWS_EV_READ);
 569
 570         pt->fds[pt->fds_count++].revents = 0;
 571 }
 572
 573 LWS_VISIBLE void
 574 lws_plat_delete_socket_from_fds(struct lws_context *context,
 575                                                 struct lws *wsi, int m)
 576 {
 577         struct lws_context_per_thread *pt = &context->pt[(int)wsi->tsi];
 578         pt->fds_count--;
 579 }
 580
 581 LWS_VISIBLE void
 582 lws_plat_service_periodic(struct lws_context *context)
 583 {
 584         /* if our parent went down, don't linger around */
 585         if (context->started_with_parent &&
 586             kill(context->started_with_parent, 0) < 0)
 587                 kill(getpid(), SIGTERM);
 588 }
 589
 590 LWS_VISIBLE int
 591 lws_plat_change_pollfd(struct lws_context *context,
 592                       struct lws *wsi, struct lws_pollfd *pfd)
 593 {
 594         return 0;
 595 }
 596
 597 LWS_VISIBLE const char *
 598 lws_plat_inet_ntop(int af, const void *src, char *dst, int cnt)
 599 {
 600         return inet_ntop(af, src, dst, cnt);
 601 }
 602
 603 static lws_filefd_type
 604 _lws_plat_file_open(struct lws *wsi, const char *filename,
 605                     unsigned long *filelen, int flags)
 606 {
 607         struct stat stat_buf;
 608         int ret = open(filename, flags, 0664);
 609
 610         if (ret < 0)
 611                 return LWS_INVALID_FILE;
 612
 613         if (fstat(ret, &stat_buf) < 0) {
 614                 close(ret);
 615                 return LWS_INVALID_FILE;
 616         }
 617         *filelen = stat_buf.st_size;
 618         return ret;
 619 }
 620
 621 static int
 622 _lws_plat_file_close(struct lws *wsi, lws_filefd_type fd)
 623 {
 624         return close(fd);
 625 }
 626
 627 unsigned long
 628 _lws_plat_file_seek_cur(struct lws *wsi, lws_filefd_type fd, long offset)
 629 {
 630         return lseek(fd, offset, SEEK_CUR);
 631 }
 632
 633 static int
 634 _lws_plat_file_read(struct lws *wsi, lws_filefd_type fd, unsigned long *amount,
 635                     unsigned char *buf, unsigned long len)
 636 {
 637         long n;
 638
 639         n = read((int)fd, buf, len);
 640         if (n == -1) {
 641                 *amount = 0;
 642                 return -1;
 643         }
 644
 645         *amount = n;
 646
 647         return 0;
 648 }
 649
 650 static int
 651 _lws_plat_file_write(struct lws *wsi, lws_filefd_type fd, unsigned long *amount,
 652                      unsigned char *buf, unsigned long len)
 653 {
 654         long n;
 655
 656         n = write((int)fd, buf, len);
 657         if (n == -1) {
 658                 *amount = 0;
 659                 return -1;
 660         }
 661
 662         *amount = n;
 663
 664         return 0;
 665 }
 666
 667
 668 LWS_VISIBLE int
 669 lws_plat_init(struct lws_context *context,
 670               struct lws_context_creation_info *info)
 671 {
 672         struct lws_context_per_thread *pt = &context->pt[0];
 673         int n = context->count_threads, fd;
 674
 675         /* master context has the global fd lookup array */
 676         context->lws_lookup = lws_zalloc(sizeof(struct lws *) *
 677                                          context->max_fds);
 678         if (context->lws_lookup == NULL) {
 679                 lwsl_err("OOM on lws_lookup array for %d connections\n",
 680                          context->max_fds);
 681                 return 1;
 682         }
 683
 684         lwsl_notice(" mem: platform fd map: %5u bytes\n",
 685                     sizeof(struct lws *) * context->max_fds);
 686         fd = open(SYSTEM_RANDOM_FILEPATH, O_RDONLY);
 687
 688         context->fd_random = fd;
 689         if (context->fd_random < 0) {
 690                 lwsl_err("Unable to open random device %s %d\n",
 691                          SYSTEM_RANDOM_FILEPATH, context->fd_random);
 692                 return 1;
 693         }
 694
 695         if (!lws_libev_init_fd_table(context) &&
 696             !lws_libuv_init_fd_table(context)) {
 697                 /* otherwise libev handled it instead */
 698
 699                 while (n--) {
 700                         if (pipe(pt->dummy_pipe_fds)) {
 701                                 lwsl_err("Unable to create pipe\n");
 702                                 return 1;
 703                         }
 704
 705                         /* use the read end of pipe as first item */
 706                         pt->fds[0].fd = pt->dummy_pipe_fds[0];
 707                         pt->fds[0].events = LWS_POLLIN;
 708                         pt->fds[0].revents = 0;
 709                         pt->fds_count = 1;
 710                         pt++;
 711                 }
 712         }
 713
 714         context->fops.open      = _lws_plat_file_open;
 715         context->fops.close     = _lws_plat_file_close;
 716         context->fops.seek_cur  = _lws_plat_file_seek_cur;
 717         context->fops.read      = _lws_plat_file_read;
 718         context->fops.write     = _lws_plat_file_write;
 719
 720 #ifdef LWS_WITH_PLUGINS
 721         if (info->plugins_dir)
 722                 lws_plat_plugins_init(context, info->plugins_dir);
 723 #endif
 724
 725         return 0;
 726 }