src/client.c

   1 /*
   2  * C Client for the DX Spider cluster program
   3  *
   4  * Eventually this program will be a complete replacement
   5  * for the perl version.
   6  *
   7  * This program provides the glue necessary to talk between
   8  * an input (eg from telnet or ax25) and the perl DXSpider
   9  * node.
  10  *
  11  * Currently, this program connects STDIN/STDOUT to the
  12  * message system used by cluster.pl
  13  *
  14  * Copyright (c) 2000 Dirk Koopman G1TLH
  15  *
  16  * $Id$
  17  */
  18
  19 #include <stdio.h>
  20 #include <sys/time.h>
  21 #include <sys/types.h>
  22 #include <unistd.h>
  23 #include <ctype.h>
  24 #include <stdlib.h>
  25 #include <stdarg.h>
  26 #include <netdb.h>
  27 #include <sys/socket.h>
  28 #include <netinet/in.h>
  29 #include <errno.h>
  30 #include <signal.h>
  31 #include <string.h>
  32 #include <termios.h>
  33 #include <regex.h>
  34
  35 #include "sel.h"
  36 #include "cmsg.h"
  37 #include "debug.h"
  38
  39 #define TEXT 1
  40 #define MSG 2
  41 #define MAXBUFL 1024
  42
  43 #ifndef MAXPATHLEN
  44 #define MAXPATHLEN 256
  45 #endif
  46
  47 #define DEFPACLEN 128
  48 #define MAXPACLEN 236
  49
  50 #define DBUF 1
  51 #define DMSG 2
  52
  53 typedef struct
  54 {
  55         int cnum;                                       /* the connection number */
  56         int sort;                                       /* the type of connection either text or msg */
  57         cmsg_t *in;                                     /* current input message being built up */
  58         cmsg_t *out;                            /* current output message being sent */
  59         cmsg_t *obuf;                           /* current output being buffered */
  60         reft *inq;                                      /* input queue */
  61         reft *outq;                                     /* output queue */
  62         sel_t *sp;                                      /* my select fcb address */
  63         struct termios t;                       /* any termios associated with this cnum */
  64         char echo;                                      /* echo characters back to this cnum */
  65         char t_set;                                     /* the termios structure is valid */
  66         char buffer_it;                         /* buffer outgoing packets for paclen */
  67 } fcb_t;
  68
  69 typedef struct
  70 {
  71         char *in;
  72         regex_t *regex;
  73 } myregex_t;
  74
  75
  76 char *node_addr = "localhost";  /* the node tcp address, can be overridden by DXSPIDER_HOST */
  77 int node_port = 27754;                  /* the tcp port of the node at the above address can be overidden by DXSPIDER_PORT*/
  78 char *call;                                             /* the caller's callsign */
  79 char *connsort;                                 /* the type of connection */
  80 fcb_t *in;                                              /* the fcb of 'stdin' that I shall use */
  81 fcb_t *node;                                    /* the fcb of the msg system */
  82 char nl = '\n';                                 /* line end character */
  83 char ending = 0;                                /* set this to end the program */
  84 char send_Z = 1;                                /* set a Z record to the node on termination */
  85 char echo = 1;                                  /* echo characters on stdout from stdin */
  86 char int_tabs = 0;                              /* interpret tabs -> spaces */
  87 char *root = "/spider";         /* root of data tree, can be overridden by DXSPIDER_ROOT  */
  88 int timeout = 60;                               /* default timeout for logins and things */
  89 int paclen = DEFPACLEN;                 /* default buffer size for outgoing packets */
  90 int tabsize = 8;                                /* default tabsize for text messages */
  91
  92 myregex_t iscallreg[] = {               /* regexes to determine whether this is a reasonable callsign */
  93         {
  94                 "^[A-Z]+[0-9]+[A-Z]+", 0
  95         },
  96         {
  97                 "^[0-9]+[A-Z]+[0-9]+[A-Z]+", 0
  98         },
  99         {
 100                 0, 0
 101         }
 102 };
 103
 104 void terminate(int);
 105
 106 /*
 107  * utility routines - various
 108  */
 109
 110 void die(char *s, ...)
 111 {
 112         char buf[2000];
 113
 114         va_list ap;
 115         va_start(ap, s);
 116         vsnprintf(buf, sizeof(buf)-1, s, ap);
 117         va_end(ap);
 118         fprintf(stderr,"%s\n", buf);
 119         terminate(-1);
 120 }
 121
 122 char *strupper(char *s)
 123 {
 124         char *d = malloc(strlen(s)+1);
 125         char *p = d;
 126
 127         if (!d)
 128                 die("out of room in strupper");
 129         while (*p++ = toupper(*s++)) ;
 130         return d;
 131 }
 132
 133 char *strlower(char *s)
 134 {
 135         char *d = malloc(strlen(s)+1);
 136         char *p = d;
 137
 138         if (!d)
 139                 die("out of room in strlower");
 140         while (*p++ = tolower(*s++)) ;
 141         return d;
 142 }
 143
 144 int eq(char *a, char *b)
 145 {
 146         return (strcmp(a, b) == 0);
 147 }
 148
 149 int xopen(char *dir, char *name, int mode)
 150 {
 151         char fn[MAXPATHLEN+1];
 152         snprintf(fn, MAXPATHLEN, "%s/%s/%s", root, dir, name);
 153         return open(fn, mode);
 154 }
 155
 156 int iscallsign(char *s)
 157 {
 158         myregex_t *rp;
 159         for (rp = iscallreg; rp->in; ++rp) {
 160                 if (regexec(rp->regex, s, 0, 0, 0) == 0)
 161                         return 1;
 162         }
 163         return 0;
 164 }
 165
 166 /*
 167  * higher level send and receive routines
 168  */
 169
 170 fcb_t *fcb_new(int cnum, int sort)
 171 {
 172         fcb_t *f = malloc(sizeof(fcb_t));
 173         if (!f)
 174                 die("no room in fcb_new");
 175         memset (f, 0, sizeof(fcb_t));
 176         f->cnum = cnum;
 177         f->sort = sort;
 178         f->inq = chain_new();
 179         f->outq = chain_new();
 180         return f;
 181 }
 182
 183 void flush_text(fcb_t *f)
 184 {
 185         if (f->obuf) {
 186                 cmsg_send(f->outq, f->obuf, 0);
 187                 f->sp->flags |= SEL_OUTPUT;
 188                 f->obuf = 0;
 189         }
 190 }
 191
 192 void send_text(fcb_t *f, char *s, int l)
 193 {
 194         cmsg_t *mp;
 195         char *p;
 196
 197         if (f->buffer_it && f->obuf) {
 198                 mp = f->obuf;
 199         } else {
 200                 f->obuf = mp = cmsg_new(paclen+1, f->sort, f);
 201         }
 202
 203         for (p = s; p < s+l; ) {
 204                 if (mp->inp >= mp->data + paclen) {
 205                         flush_text(f);
 206                         f->obuf = mp = cmsg_new(paclen+1, f->sort, f);
 207                 }
 208                 *mp->inp++ = *p++;
 209         }
 210         if (mp->inp >= mp->data + paclen) {
 211                 flush_text(f);
 212                 f->obuf = mp = cmsg_new(paclen+1, f->sort, f);
 213         }
 214         *mp->inp++ = nl;
 215         if (!f->buffer_it)
 216                 flush_text(f);
 217 }
 218
 219 void send_msg(fcb_t *f, char let, char *s, int l)
 220 {
 221         cmsg_t *mp;
 222         int ln;
 223         int myl = strlen(call)+2+l;
 224
 225         mp = cmsg_new(myl+4+1, f->sort, f);
 226         ln = htonl(myl);
 227         memcpy(mp->inp, &ln, 4);
 228         mp->inp += 4;
 229         *mp->inp++ = let;
 230         strcpy(mp->inp, call);
 231         mp->inp += strlen(call);
 232         *mp->inp++ = '|';
 233         if (l > 0) {
 234                 memcpy(mp->inp, s, l);
 235                 mp->inp += l;
 236         }
 237         *mp->inp = 0;
 238         cmsg_send(f->outq, mp, 0);
 239         f->sp->flags |= SEL_OUTPUT;
 240 }
 241
 242 /*
 243  * the callback (called by sel_run) that handles all the inputs and outputs
 244  */
 245
 246 int fcb_handler(sel_t *sp, int in, int out, int err)
 247 {
 248         fcb_t *f = sp->fcb;
 249         cmsg_t *mp, *omp;
 250
 251         /* input modes */
 252         if (in) {
 253                 char *p, buf[MAXBUFL];
 254                 int r;
 255
 256                 /* read what we have into a buffer */
 257                 r = read(f->cnum, buf, MAXBUFL);
 258                 if (r < 0) {
 259                         switch (errno) {
 260                         case EINTR:
 261                         case EINPROGRESS:
 262                         case EAGAIN:
 263                                 goto lout;
 264                         default:
 265                                 if (f->sort == MSG)
 266                                         send_Z = 0;
 267                                 ending++;
 268                                 return 0;
 269                         }
 270                 } else if (r == 0) {
 271                         if (f->sort == MSG)
 272                                 send_Z = 0;
 273                         ending++;
 274                         return 0;
 275                 }
 276
 277                 dbgdump(DBUF, "in ->", buf, r);
 278
 279                 /* create a new message buffer if required */
 280                 if (!f->in)
 281                         f->in = cmsg_new(MAXBUFL+1, f->sort, f);
 282                 mp = f->in;
 283
 284                 switch (f->sort) {
 285                 case TEXT:
 286                         p = buf;
 287                         if (f->echo)
 288                                 omp = cmsg_new(3*r+1, f->sort, f);
 289                         while (r > 0 && p < &buf[r]) {
 290
 291                                 /* echo processing */
 292                                 if (f->echo) {
 293                                         switch (*p) {
 294                                         case '\b':
 295                                         case 0x7f:
 296                                                 strcpy(omp->inp, "\b \b");
 297                                                 omp->inp += strlen(omp->inp);
 298                                                 break;
 299                                         default:
 300                                                 *omp->inp++ = *p;
 301                                         }
 302                                 }
 303
 304                                 /* character processing */
 305                                 switch (*p) {
 306                                 case '\t':
 307                                         if (int_tabs) {
 308                                                 memset(mp->inp, ' ', tabsize);
 309                                                 mp->inp += tabsize;
 310                                                 ++p;
 311                                         } else {
 312                                                 *mp->inp++ = *p++;
 313                                         }
 314                                         break;
 315                                 case '\b':
 316                                 case 0x7f:
 317                                         if (mp->inp > mp->data)
 318                                                 mp->inp--;
 319                                         ++p;
 320                                         break;
 321                                 default:
 322                                         if (nl == '\n' && *p == '\r') {   /* ignore \r in telnet mode (ugh) */
 323                                                 p++;
 324                                         } else if (*p == nl) {
 325                                                 if (mp->inp == mp->data)
 326                                                         *mp->inp++ = ' ';
 327                                                 *mp->inp = 0;              /* zero terminate it, but don't include it in the length */
 328                                                 dbgdump(DMSG, "QUEUE TEXT", mp->data, mp->inp-mp->data);
 329                                                 cmsg_send(f->inq, mp, 0);
 330                                                 f->in = mp = cmsg_new(MAXBUFL+1, f->sort, f);
 331                                                 ++p;
 332                                         } else {
 333                                                 if (mp->inp < &mp->data[MAXBUFL-8])
 334                                                         *mp->inp++ = *p++;
 335                                                 else {
 336                                                         mp->inp = mp->data;
 337                                                 }
 338                                         }
 339                                 }
 340                         }
 341
 342                         /* queue any echo text */
 343                         if (f->echo) {
 344                                 dbgdump(DMSG, "QUEUE ECHO TEXT", omp->data, omp->inp - omp->data);
 345                                 cmsg_send(f->outq, omp, 0);
 346                                 f->sp->flags |= SEL_OUTPUT;
 347                         }
 348
 349                         break;
 350
 351                 case MSG:
 352                         p = buf;
 353                         while (r > 0 && p < &buf[r]) {
 354
 355                                 /* build up the size into the likely message length (yes I know it's a short) */
 356                                 switch (mp->state) {
 357                                 case 0:
 358                                 case 1:
 359                                         mp->state++;
 360                                         break;
 361                                 case 2:
 362                                 case 3:
 363                                         mp->size = (mp->size << 8) | (*p++ & 0xff);
 364                                         if (mp->size > MAXBUFL)
 365                                                 die("Message size too big from node (%d > %d)", mp->size, MAXBUFL);
 366                                         mp->state++;
 367                                         break;
 368                                 default:
 369                                         if (mp->inp - mp->data < mp->size) {
 370                                                 *mp->inp++ = *p++;
 371                                         }
 372                                         if (mp->inp - mp->data >= mp->size) {
 373                                                 /* kick it upstairs */
 374                                                 dbgdump(DMSG, "QUEUE MSG", mp->data, mp->inp - mp->data);
 375                                                 cmsg_send(f->inq, mp, 0);
 376                                                 mp = f->in = cmsg_new(MAXBUFL+1, f->sort, f);
 377                                         }
 378                                 }
 379                         }
 380                         break;
 381
 382                 default:
 383                         die("invalid sort (%d) in input handler", f->sort);
 384                 }
 385         }
 386
 387         /* output modes */
 388 lout:;
 389         if (out) {
 390                 int l, r;
 391
 392                 if (!f->out) {
 393                         mp = f->out = cmsg_next(f->outq);
 394                         if (!mp) {
 395                                 sp->flags &= ~SEL_OUTPUT;
 396                                 return 0;
 397                         }
 398                         mp->inp = mp->data;
 399                 }
 400                 l = mp->size - (mp->inp - mp->data);
 401                 if (l > 0) {
 402
 403                         dbgdump(DBUF, "<-out", mp->inp, l);
 404
 405                         r = write(f->cnum, mp->inp, l);
 406                         if (r < 0) {
 407                                 switch (errno) {
 408                                 case EINTR:
 409                                 case EINPROGRESS:
 410                                 case EAGAIN:
 411                                         goto lend;
 412                                 default:
 413                                         if (f->sort == MSG)
 414                                                 send_Z = 0;
 415                                         ending++;
 416                                         return;
 417                                 }
 418                         } else if (r > 0) {
 419                                 mp->inp += r;
 420                         }
 421                 } else if (l < 0)
 422                         die("got negative length in handler on node");
 423                 if (mp->inp - mp->data >= mp->size) {
 424                         cmsg_callback(mp, 0);
 425                         f->out = 0;
 426                 }
 427         }
 428 lend:;
 429         return 0;
 430 }
 431
 432 /*
 433  * things to do with initialisation
 434  */
 435
 436 void initargs(int argc, char *argv[])
 437 {
 438         int i, c, err = 0;
 439
 440         while ((c = getopt(argc, argv, "h:p:x:")) > 0) {
 441                 switch (c) {
 442                 case 'h':
 443                         node_addr = optarg;
 444                         break;
 445                 case 'l':
 446                         paclen = atoi(optarg);
 447                         if (paclen < 80)
 448                                 paclen = 80;
 449                         if (paclen > MAXPACLEN)
 450                                 paclen = MAXPACLEN;
 451                         break;
 452                 case 'p':
 453                         node_port = atoi(optarg);
 454                         break;
 455                 case 'x':
 456                         dbginit("client");
 457                         dbgset(atoi(optarg));
 458                         break;
 459                 default:
 460                         ++err;
 461                         goto lerr;
 462                 }
 463         }
 464
 465 lerr:
 466         if (err) {
 467                 die("usage: client [-x n|-h<host>|-p<port>|-l<paclen>] <call>|login [local|telnet|ax25]");
 468         }
 469
 470         if (optind < argc) {
 471                 call = strupper(argv[optind]);
 472                 ++optind;
 473         }
 474         if (!call)
 475                 die("Must have at least a callsign (for now)");
 476
 477         if (optind < argc) {
 478                 connsort = strlower(argv[optind]);
 479                 if (eq(connsort, "telnet") || eq(connsort, "local")) {
 480                         nl = '\n';
 481                         echo = 1;
 482                 } else if (eq(connsort, "ax25")) {
 483                         nl = '\r';
 484                         echo = 0;
 485                 } else {
 486                         die("2nd argument must be \"telnet\" or \"ax25\" or \"local\"");
 487                 }
 488         } else {
 489                 connsort = "local";
 490                 nl = '\n';
 491                 echo = 1;
 492         }
 493
 494         /* this is kludgy, but hey so is the rest of this! */
 495         if (!eq(connsort, "ax25") && paclen == DEFPACLEN) {
 496                 paclen = MAXPACLEN;
 497         }
 498 }
 499
 500 void connect_to_node()
 501 {
 502         struct hostent *hp, *gethostbyname();
 503         struct sockaddr_in server;
 504         int nodef;
 505         sel_t *sp;
 506
 507         if ((hp = gethostbyname(node_addr)) == 0)
 508                 die("Unknown host tcp host %s for printer", node_addr);
 509
 510         memset(&server, 0, sizeof server);
 511         server.sin_family = AF_INET;
 512         memcpy(&server.sin_addr, hp->h_addr, hp->h_length);
 513         server.sin_port = htons(node_port);
 514
 515         nodef = socket(AF_INET, SOCK_STREAM, 0);
 516         if (nodef < 0)
 517                 die("Can't open socket to %s port %d (%d)", node_addr, node_port, errno);
 518
 519         if (connect(nodef, (struct sockaddr *) &server, sizeof server) < 0) {
 520                 die("Error on connect to %s port %d (%d)", node_addr, node_port, errno);
 521         }
 522         node = fcb_new(nodef, MSG);
 523         node->sp = sel_open(nodef, node, "Msg System", fcb_handler, MSG, SEL_INPUT);
 524
 525 }
 526
 527 /*
 528  * things to do with going away
 529  */
 530
 531 void term_timeout(int i)
 532 {
 533         /* none of this is going to be reused so don't bother cleaning up properly */
 534         if (in && in->t_set)
 535                 tcsetattr(0, TCSANOW, &in->t);
 536         if (node) {
 537                 close(node->cnum);
 538         }
 539         exit(i);
 540 }
 541
 542 void terminate(int i)
 543 {
 544         if (node && send_Z && call) {
 545                 send_msg(node, 'Z', "", 0);
 546         }
 547
 548         signal(SIGALRM, term_timeout);
 549         alarm(10);
 550
 551         while ((in && !is_chain_empty(in->outq)) ||
 552                    (node && !is_chain_empty(node->outq))) {
 553                 sel_run();
 554         }
 555         if (in && in->t_set)
 556                 tcsetattr(0, TCSADRAIN, &in->t);
 557         if (node)
 558                 close(node->cnum);
 559         exit(i);
 560 }
 561
 562 void login_timeout(int i)
 563 {
 564         write(0, "Timed Out", 10);
 565         write(0, &nl, 1);
 566         sel_run();                                      /* force a coordination */
 567         if (in && in->t_set)
 568                 tcsetattr(0, TCSANOW, &in->t);
 569         exit(i);
 570 }
 571
 572 /*
 573  * things to do with ongoing processing of inputs
 574  */
 575
 576 void process_stdin()
 577 {
 578         cmsg_t *mp = cmsg_next(in->inq);
 579         if (mp) {
 580                 dbg(DMSG, "MSG size: %d", mp->size);
 581
 582                 if (mp->size > 0 && mp->inp > mp->data) {
 583                         send_msg(node, 'I', mp->data, mp->size);
 584                 }
 585                 cmsg_callback(mp, 0);
 586         }
 587 }
 588
 589 void process_node()
 590 {
 591         cmsg_t *mp = cmsg_next(node->inq);
 592         if (mp) {
 593                 dbg(DMSG, "MSG size: %d", mp->size);
 594
 595                 if (mp->size > 0 && mp->inp > mp->data) {
 596                         char *p = strchr(mp->data, '|');
 597                         if (p)
 598                                 p++;
 599                         switch (mp->data[0]) {
 600                         case 'Z':
 601                                 send_Z = 0;
 602                                 ending++;
 603                                 return;
 604                         case 'E':
 605                                 if (isdigit(*p))
 606                                         in->echo = *p - '0';
 607                                 break;
 608                         case 'B':
 609                                 if (isdigit(*p))
 610                                         in->buffer_it = *p - '0';
 611                                 break;
 612                         case 'D':
 613                                 if (p) {
 614                                         int l = mp->inp - (unsigned char *) p;
 615                                         send_text(in, p, l);
 616                                 }
 617                                 break;
 618                         default:
 619                                 break;
 620                         }
 621                 }
 622                 cmsg_callback(mp, 0);
 623         } else {
 624                 flush_text(in);
 625         }
 626 }
 627
 628 /*
 629  * the program itself....
 630  */
 631
 632 main(int argc, char *argv[])
 633 {
 634         /* set up environment */
 635         {
 636                 char *p = getenv("DXSPIDER_ROOT");
 637                 if (p)
 638                         root = p;
 639                 p = getenv("DXSPIDER_HOST");
 640                 if (p)
 641                         node_addr = p;
 642                 p = getenv("DXSPIDER_PORT");
 643                 if (p)
 644                         node_port = atoi(p);
 645                 p = getenv("DXSPIDER_PACLEN");
 646                 if (p) {
 647                         paclen = atoi(p);
 648                         if (paclen < 80)
 649                                 paclen = 80;
 650                         if (paclen > MAXPACLEN)
 651                                 paclen = MAXPACLEN;
 652                 }
 653         }
 654
 655         /* get program arguments, initialise stuff */
 656         initargs(argc, argv);
 657         sel_init(10, 0, 10000);
 658
 659         /* trap signals */
 660         signal(SIGHUP, SIG_IGN);
 661         signal(SIGINT, terminate);
 662         signal(SIGQUIT, terminate);
 663         signal(SIGTERM, terminate);
 664 #ifdef SIGPWR
 665         signal(SIGPWR, terminate);
 666 #endif
 667
 668         /* compile regexes for iscallsign */
 669         {
 670                 myregex_t *rp;
 671                 for (rp = iscallreg; rp->in; ++rp) {
 672                         regex_t reg;
 673                         int r = regcomp(&reg, rp->in, REG_EXTENDED|REG_ICASE|REG_NOSUB);
 674                         if (r)
 675                                 die("regcomp returned %d for '%s'", r, rp->in);
 676                         rp->regex = malloc(sizeof(regex_t));
 677                         if (!rp->regex)
 678                                 die("out of room - compiling regexes");
 679                         *rp->regex = reg;
 680                 }
 681         }
 682
 683         /* is this a login? */
 684         if (eq(call, "LOGIN")) {
 685                 char buf[MAXPACLEN+1];
 686                 int r;
 687                 int f = xopen("data", "issue", 0);
 688                 if (f > 0) {
 689                         while ((r = read(f, buf, paclen)) > 0) {
 690                                 if (nl != '\n') {
 691                                         char *p;
 692                                         for (p = buf; p < &buf[r]; ++p) {
 693                                                 if (*p == '\n')
 694                                                         *p = nl;
 695                                         }
 696                                 }
 697                                 write(0, buf, r);
 698                         }
 699                         close(f);
 700                 }
 701                 signal(SIGALRM, login_timeout);
 702                 alarm(timeout);
 703                 write(0, "login: ", 7);
 704                 r = read(0, buf, 20);
 705                 if (r <= 0)
 706                         die("No login or error (%d)", errno);
 707                 signal(SIGALRM, SIG_IGN);
 708                 alarm(0);
 709                 while (r > 0) {
 710                         if (buf[r-1] == ' ' || buf[r-1] == '\r' || buf[r-1] == '\n')
 711                                 --r;
 712                         else
 713                                 break;
 714                 }
 715                 buf[r] = 0;
 716                 call = strupper(buf);
 717                 if (!iscallsign(call)) {
 718                         die("Sorry, %s isn't a valid callsign", buf);
 719                 }
 720         }
 721
 722         /* connect up stdin */
 723         in = fcb_new(0, TEXT);
 724         in->sp = sel_open(0, in, "STDIN", fcb_handler, TEXT, SEL_INPUT);
 725         if (tcgetattr(0, &in->t) < 0) {
 726                 echo = 0;
 727                 in->t_set = 0;
 728         } else {
 729                 struct termios t = in->t;
 730                 t.c_lflag &= ~(ECHO|ECHONL|ICANON);
 731                 if (tcsetattr(0, TCSANOW, &t) < 0)
 732                         die("tcsetattr (%d)", errno);
 733                 in->echo = echo;
 734                 in->t_set = 1;
 735         }
 736         in->buffer_it = 1;
 737
 738         /* connect up node */
 739         connect_to_node();
 740
 741         /* tell the cluster who I am */
 742         send_msg(node, 'A', connsort, strlen(connsort));
 743
 744         /* main processing loop */
 745         while (!ending) {
 746                 sel_run();
 747                 if (!ending) {
 748                         process_stdin();
 749                         process_node();
 750                 }
 751         }
 752         terminate(0);
 753 }
 754
 755
 756
 757
 758
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