server/seshigh.c

   1 /*
   2  * Copyright (c) 1995, Index Data
   3  * See the file LICENSE for details.
   4  * Sebastian Hammer, Adam Dickmeiss
   5  *
   6  * $Log: seshigh.c,v $
   7  * Revision 1.49  1995-10-16 13:51:53  quinn
   8  * Changes to provide Especs to the backend.
   9  *
  10  * Revision 1.48  1995/10/06  08:51:20  quinn
  11  * Added Write-buffer.
  12  *
  13  * Revision 1.47  1995/08/29  14:24:16  quinn
  14  * Added second half of close-handshake
  15  *
  16  * Revision 1.46  1995/08/29  11:17:58  quinn
  17  * Added code to receive close
  18  *
  19  * Revision 1.45  1995/08/21  09:11:00  quinn
  20  * Smallish fixes to suppport new formats.
  21  *
  22  * Revision 1.44  1995/08/17  12:45:25  quinn
  23  * Fixed minor problems with GRS-1. Added support in c&s.
  24  *
  25  * Revision 1.43  1995/08/15  12:00:31  quinn
  26  * Updated External
  27  *
  28  * Revision 1.42  1995/08/15  11:16:50  quinn
  29  *
  30  * Revision 1.41  1995/08/02  10:23:06  quinn
  31  * Smallish
  32  *
  33  * Revision 1.40  1995/07/31  14:34:26  quinn
  34  * Fixed bug in process_searchResponse (numberOfRecordsReturned).
  35  *
  36  * Revision 1.39  1995/06/27  13:21:00  quinn
  37  * SUTRS support
  38  *
  39  * Revision 1.38  1995/06/19  12:39:11  quinn
  40  * Fixed bug in timeout code. Added BER dumper.
  41  *
  42  * Revision 1.37  1995/06/16  13:16:14  quinn
  43  * Fixed Defaultdiagformat.
  44  *
  45  * Revision 1.36  1995/06/16  10:31:36  quinn
  46  * Added session timeout.
  47  *
  48  * Revision 1.35  1995/06/15  07:45:14  quinn
  49  * Moving to v3.
  50  *
  51  * Revision 1.34  1995/06/14  15:26:46  quinn
  52  * *** empty log message ***
  53  *
  54  * Revision 1.33  1995/06/06  14:57:05  quinn
  55  * Better diagnostics.
  56  *
  57  * Revision 1.32  1995/06/06  08:41:44  quinn
  58  * Better diagnostics.
  59  *
  60  * Revision 1.31  1995/06/06  08:15:37  quinn
  61  * Cosmetic.
  62  *
  63  * Revision 1.30  1995/06/05  10:53:32  quinn
  64  * Added a better SCAN.
  65  *
  66  * Revision 1.29  1995/06/01  11:25:03  quinn
  67  * Smallish.
  68  *
  69  * Revision 1.28  1995/06/01  11:21:01  quinn
  70  * Attempting to fix a bug in pack-records. replaced break with continue
  71  * for large records, according to standard.
  72  *
  73  * Revision 1.27  1995/05/29  08:12:06  quinn
  74  * Moved oid to util
  75  *
  76  * Revision 1.26  1995/05/18  13:02:12  quinn
  77  * Smallish.
  78  *
  79  * Revision 1.25  1995/05/17  08:42:26  quinn
  80  * Transfer auth info to backend. Allow backend to reject init gracefully.
  81  *
  82  * Revision 1.24  1995/05/16  08:51:04  quinn
  83  * License, documentation, and memory fixes
  84  *
  85  * Revision 1.23  1995/05/15  13:25:10  quinn
  86  * Fixed memory bug.
  87  *
  88  * Revision 1.22  1995/05/15  11:56:39  quinn
  89  * Asynchronous facilities. Restructuring of seshigh code.
  90  *
  91  * Revision 1.21  1995/05/02  08:53:19  quinn
  92  * Trying in vain to fix comm with ISODE
  93  *
  94  * Revision 1.20  1995/04/20  15:13:00  quinn
  95  * Cosmetic
  96  *
  97  * Revision 1.19  1995/04/18  08:15:34  quinn
  98  * Added dynamic memory allocation on encoding (whew). Code is now somewhat
  99  * neater. We'll make the same change for decoding one day.
 100  *
 101  * Revision 1.18  1995/04/17  11:28:25  quinn
 102  * Smallish
 103  *
 104  * Revision 1.17  1995/04/10  10:23:36  quinn
 105  * Some work to add scan and other things.
 106  *
 107  * Revision 1.16  1995/03/31  09:18:55  quinn
 108  * Added logging.
 109  *
 110  * Revision 1.15  1995/03/30  14:03:23  quinn
 111  * Added RFC1006 as separate library
 112  *
 113  * Revision 1.14  1995/03/30  12:18:17  quinn
 114  * Fixed bug.
 115  *
 116  * Revision 1.13  1995/03/30  09:09:24  quinn
 117  * Added state-handle and some support for asynchronous activities.
 118  *
 119  * Revision 1.12  1995/03/29  15:40:16  quinn
 120  * Ongoing work. Statserv is now dynamic by default
 121  *
 122  * Revision 1.11  1995/03/28  09:16:21  quinn
 123  * Added record packing to the search request
 124  *
 125  * Revision 1.10  1995/03/27  08:34:24  quinn
 126  * Added dynamic server functionality.
 127  * Released bindings to session.c (is now redundant)
 128  *
 129  * Revision 1.9  1995/03/22  15:01:26  quinn
 130  * Adjusting record packing.
 131  *
 132  * Revision 1.8  1995/03/22  10:13:21  quinn
 133  * Working on record packer
 134  *
 135  * Revision 1.7  1995/03/21  15:53:31  quinn
 136  * Little changes.
 137  *
 138  * Revision 1.6  1995/03/21  12:30:09  quinn
 139  * Beginning to add support for record packing.
 140  *
 141  * Revision 1.5  1995/03/17  10:44:13  quinn
 142  * Added catch of null-string in makediagrec
 143  *
 144  * Revision 1.4  1995/03/17  10:18:08  quinn
 145  * Added memory management.
 146  *
 147  * Revision 1.3  1995/03/16  17:42:39  quinn
 148  * Little changes
 149  *
 150  * Revision 1.2  1995/03/16  13:29:01  quinn
 151  * Partitioned server.
 152  *
 153  * Revision 1.1  1995/03/15  16:02:10  quinn
 154  * Modded session.c to seshigh.c
 155  *
 156  */
 157
 158 /*
 159  * Frontend server logic.
 160  *
 161  * This code receives incoming APDUs, and handles client requests by means
 162  * of the backend API.
 163  *
 164  * Some of the code is getting quite involved, compared to simpler servers -
 165  * primarily because it is asynchronous both in the communication with
 166  * the user and the backend. We think the complexity will pay off in
 167  * the form of greater flexibility when more asynchronous facilities
 168  * are implemented.
 169  *
 170  * Memory management has become somewhat involved. In the simple case, where
 171  * only one PDU is pending at a time, it will simply reuse the same memory,
 172  * once it has found its working size. When we enable multiple concurrent
 173  * operations, perhaps even with multiple parallel calls to the backend, it
 174  * will maintain a pool of buffers for encoding and decoding, trying to
 175  * minimize memory allocation/deallocation during normal operation.
 176  *
 177  * TODOs include (and will be done in order of public interest):
 178  *
 179  * Support for EXPLAIN - provide simple meta-database system.
 180  * Support for access control.
 181  * Support for resource control.
 182  * Support for extended services - primarily Item Order.
 183  * Rest of Z39.50-1994
 184  *
 185  */
 186
 187 #include <stdlib.h>
 188 #include <stdio.h>
 189 #include <unistd.h>
 190 #include <assert.h>
 191 #include <sys/time.h>
 192
 193 #include <dmalloc.h>
 194 #include <comstack.h>
 195 #include <eventl.h>
 196 #include <session.h>
 197 #include <proto.h>
 198 #include <oid.h>
 199 #include <log.h>
 200 #include <statserv.h>
 201
 202 #include <backend.h>
 203
 204 static int process_request(association *assoc);
 205 void backend_response(IOCHAN i, int event);
 206 static int process_response(association *assoc, request *req, Z_APDU *res);
 207 static Z_APDU *process_initRequest(association *assoc, request *reqb);
 208 static Z_APDU *process_searchRequest(association *assoc, request *reqb,
 209     int *fd);
 210 static Z_APDU *response_searchRequest(association *assoc, request *reqb,
 211     bend_searchresult *bsrt, int *fd);
 212 static Z_APDU *process_presentRequest(association *assoc, request *reqb,
 213     int *fd);
 214 static Z_APDU *process_scanRequest(association *assoc, request *reqb, int *fd);
 215 static void process_close(association *assoc, request *reqb);
 216
 217 static FILE *apduf = 0; /* for use in static mode */
 218 static statserv_options_block *control_block = 0;
 219
 220 /*
 221  * Create and initialize a new association-handle.
 222  *  channel  : iochannel for the current line.
 223  *  link     : communications channel.
 224  * Returns: 0 or a new association handle.
 225  */
 226 association *create_association(IOCHAN channel, COMSTACK link)
 227 {
 228     association *new;
 229
 230     if (!control_block)
 231         control_block = statserv_getcontrol();
 232     if (!(new = malloc(sizeof(*new))))
 233         return 0;
 234     new->client_chan = channel;
 235     new->client_link = link;
 236     if (!(new->decode = odr_createmem(ODR_DECODE)) ||
 237         !(new->encode = odr_createmem(ODR_ENCODE)))
 238         return 0;
 239     if (*control_block->apdufile)
 240     {
 241         char filename[256];
 242         FILE *f;
 243
 244         strcpy(filename, control_block->apdufile);
 245         if (!(new->print = odr_createmem(ODR_PRINT)))
 246             return 0;
 247         if (*control_block->apdufile != '-')
 248         {
 249             strcpy(filename, control_block->apdufile);
 250             if (!control_block->dynamic)
 251             {
 252                 if (!apduf)
 253                 {
 254                     if (!(apduf = fopen(filename, "w")))
 255                     {
 256                         logf(LOG_WARN|LOG_ERRNO, "%s", filename);
 257                         return 0;
 258                     }
 259                     setvbuf(apduf, 0, _IONBF, 0);
 260                 }
 261                 f = apduf;
 262             }
 263             else
 264             {
 265                 sprintf(filename + strlen(filename), ".%d", getpid());
 266                 if (!(f = fopen(filename, "w")))
 267                 {
 268                     logf(LOG_WARN|LOG_ERRNO, "%s", filename);
 269                     return 0;
 270                 }
 271                 setvbuf(f, 0, _IONBF, 0);
 272             }
 273             odr_setprint(new->print, f);
 274         }
 275     }
 276     else
 277         new->print = 0;
 278     new->input_buffer = 0;
 279     new->input_buffer_len = 0;
 280     new->backend = 0;
 281     new->state = ASSOC_NEW;
 282     request_initq(&new->incoming);
 283     request_initq(&new->outgoing);
 284     new->proto = cs_getproto(link);
 285     return new;
 286 }
 287
 288 /*
 289  * Free association and release resources.
 290  */
 291 void destroy_association(association *h)
 292 {
 293     odr_destroy(h->decode);
 294     odr_destroy(h->encode);
 295     if (h->print)
 296         odr_destroy(h->print);
 297     if (h->input_buffer)
 298         free(h->input_buffer);
 299     if (h->backend)
 300         bend_close(h->backend);
 301     while (request_deq(&h->incoming));
 302     while (request_deq(&h->outgoing));
 303     free(h);
 304 }
 305
 306 static void do_close(association *a, int reason, char *message)
 307 {
 308     Z_APDU apdu;
 309     Z_Close *cls = zget_Close(a->encode);
 310     request *req = request_get();
 311
 312     /* Purge request queue */
 313     while (request_deq(&a->incoming));
 314     while (request_deq(&a->outgoing));
 315     if (a->version >= 3)
 316     {
 317         logf(LOG_DEBUG, "Generating Close PDU");
 318         apdu.which = Z_APDU_close;
 319         apdu.u.close = cls;
 320         *cls->closeReason = reason;
 321         cls->diagnosticInformation = message;
 322         process_response(a, req, &apdu);
 323         iochan_settimeout(a->client_chan, 60);
 324     }
 325     else
 326     {
 327         logf(LOG_DEBUG, "v2 client. No Close PDU");
 328         iochan_setevent(a->client_chan, EVENT_TIMEOUT); /* force imm close */
 329     }
 330     a->state = ASSOC_DEAD;
 331 }
 332
 333 /*
 334  * This is where PDUs from the client are read and the further
 335  * processing is initiated. Flow of control moves down through the
 336  * various process_* functions below, until the encoded result comes back up
 337  * to the output handler in here.
 338  *
 339  *  h     : the I/O channel that has an outstanding event.
 340  *  event : the current outstanding event.
 341  */
 342 void ir_session(IOCHAN h, int event)
 343 {
 344     int res;
 345     association *assoc = iochan_getdata(h);
 346     COMSTACK conn = assoc->client_link;
 347     request *req;
 348
 349     assert(h && conn && assoc);
 350     if (event == EVENT_TIMEOUT)
 351     {
 352         if (assoc->state != ASSOC_UP)
 353         {
 354             logf(LOG_LOG, "Final timeout - closing connection.");
 355             cs_close(conn);
 356             destroy_association(assoc);
 357             iochan_destroy(h);
 358         }
 359         else
 360         {
 361             logf(LOG_LOG, "Session idle too long. Sending close.");
 362             do_close(assoc, Z_Close_lackOfActivity, 0);
 363         }
 364         return;
 365     }
 366     if (event & EVENT_INPUT || event & EVENT_WORK) /* input */
 367     {
 368         if (event & EVENT_INPUT)
 369         {
 370             logf(LOG_DEBUG, "ir_session (input)");
 371             assert(assoc && conn);
 372             /* We aren't speaking to this fellow */
 373             if (assoc->state == ASSOC_DEAD)
 374             {
 375                 logf(LOG_LOG, "Closed connection after reject");
 376                 cs_close(conn);
 377                 destroy_association(assoc);
 378                 iochan_destroy(h);
 379                 return;
 380             }
 381             if ((res = cs_get(conn, &assoc->input_buffer,
 382                 &assoc->input_buffer_len)) <= 0)
 383             {
 384                 logf(LOG_LOG, "Connection closed by client");
 385                 cs_close(conn);
 386                 destroy_association(assoc);
 387                 iochan_destroy(h);
 388                 return;
 389             }
 390             else if (res == 1) /* incomplete read - wait for more  */
 391                 return;
 392             if (cs_more(conn)) /* more stuff - call us again later, please */
 393                 iochan_setevent(h, EVENT_INPUT);
 394
 395             /* we got a complete PDU. Let's decode it */
 396             logf(LOG_DEBUG, "Got PDU, %d bytes", res);
 397             req = request_get(); /* get a new request structure */
 398             odr_reset(assoc->decode);
 399             odr_setbuf(assoc->decode, assoc->input_buffer, res, 0);
 400             if (!z_APDU(assoc->decode, &req->request, 0))
 401             {
 402                 logf(LOG_LOG, "ODR error on incoming PDU: %s",
 403                     odr_errlist[odr_geterror(assoc->decode)]);
 404                 logf(LOG_LOG, "PDU dump:");
 405                 odr_dumpBER(log_file(), assoc->input_buffer, res);
 406                 do_close(assoc, Z_Close_protocolError, "Malformed package");
 407                 return;
 408             }
 409             req->request_mem = odr_extract_mem(assoc->decode);
 410             if (assoc->print && !z_APDU(assoc->print, &req->request, 0))
 411             {
 412                 logf(LOG_WARN, "ODR print error: %s",
 413                     odr_errlist[odr_geterror(assoc->print)]);
 414                 odr_reset(assoc->print);
 415             }
 416             request_enq(&assoc->incoming, req);
 417         }
 418
 419         /* can we do something yet? */
 420         req = request_head(&assoc->incoming);
 421         if (req->state == REQUEST_IDLE)
 422             if (process_request(assoc) < 0)
 423                 do_close(assoc, Z_Close_systemProblem, "Unknown error");
 424     }
 425     if (event & EVENT_OUTPUT)
 426     {
 427         request *req = request_head(&assoc->outgoing);
 428
 429         logf(LOG_DEBUG, "ir_session (output)");
 430         req->state = REQUEST_PENDING;
 431         switch (res = cs_put(conn, req->response, req->len_response))
 432         {
 433             case -1:
 434                 logf(LOG_LOG, "Connection closed by client");
 435                 cs_close(conn);
 436                 destroy_association(assoc);
 437                 iochan_destroy(h);
 438                 break;
 439             case 0: /* all sent - release the request structure */
 440                 logf(LOG_DEBUG, "Wrote PDU, %d bytes", req->len_response);
 441                 odr_release_mem(req->request_mem);
 442                 request_deq(&assoc->outgoing);
 443                 request_release(req);
 444                 if (!request_head(&assoc->outgoing))
 445                     iochan_clearflag(h, EVENT_OUTPUT);
 446                 break;
 447             /* value of 1 -- partial send -- is simply ignored */
 448         }
 449     }
 450     if (event & EVENT_EXCEPT)
 451     {
 452         logf(LOG_DEBUG, "ir_session (exception)");
 453         cs_close(conn);
 454         destroy_association(assoc);
 455         iochan_destroy(h);
 456     }
 457 }
 458
 459 /*
 460  * Initiate request processing.
 461  */
 462 static int process_request(association *assoc)
 463 {
 464     request *req = request_head(&assoc->incoming);
 465     int fd = -1;
 466     Z_APDU *res;
 467
 468     logf(LOG_DEBUG, "process_request");
 469     assert(req && req->state == REQUEST_IDLE);
 470     switch (req->request->which)
 471     {
 472         case Z_APDU_initRequest:
 473             res = process_initRequest(assoc, req); break;
 474         case Z_APDU_searchRequest:
 475             res = process_searchRequest(assoc, req, &fd); break;
 476         case Z_APDU_presentRequest:
 477             res = process_presentRequest(assoc, req, &fd); break;
 478         case Z_APDU_scanRequest:
 479             res = process_scanRequest(assoc, req, &fd); break;
 480         case Z_APDU_close:
 481             process_close(assoc, req); return 0;
 482         default:
 483             logf(LOG_WARN, "Bad APDU received");
 484             return -1;
 485     }
 486     if (res)
 487     {
 488         logf(LOG_DEBUG, "  result immediately available");
 489         return process_response(assoc, req, res);
 490     }
 491     else if (fd < 0)
 492     {
 493         logf(LOG_WARN, "   bad result");
 494         return -1;
 495     }
 496     else /* no result yet - one will be provided later */
 497     {
 498         IOCHAN chan;
 499
 500         /* Set up an I/O handler for the fd supplied by the backend */
 501
 502         logf(LOG_DEBUG, "   establishing handler for result");
 503         req->state = REQUEST_PENDING;
 504         if (!(chan = iochan_create(fd, backend_response, EVENT_INPUT)))
 505             abort();
 506         iochan_setdata(chan, assoc);
 507         return 0;
 508     }
 509 }
 510
 511 /*
 512  * Handle message from the backend.
 513  */
 514 void backend_response(IOCHAN i, int event)
 515 {
 516     association *assoc = iochan_getdata(i);
 517     request *req = request_head(&assoc->incoming);
 518     Z_APDU *res;
 519     int fd;
 520
 521     logf(LOG_DEBUG, "backend_response");
 522     assert(assoc && req && req->state != REQUEST_IDLE);
 523     /* determine what it is we're waiting for */
 524     switch (req->request->which)
 525     {
 526         case Z_APDU_searchRequest:
 527             res = response_searchRequest(assoc, req, 0, &fd); break;
 528 #if 0
 529         case Z_APDU_presentRequest:
 530             res = response_presentRequest(assoc, req, 0, &fd); break;
 531         case Z_APDU_scanRequest:
 532             res = response_scanRequest(assoc, req, 0, &fd); break;
 533 #endif
 534         default:
 535             logf(LOG_WARN, "Serious programmer's lapse or bug");
 536             abort();
 537     }
 538     if ((res && process_response(assoc, req, res) < 0) || fd < 0)
 539     {
 540         logf(LOG_LOG, "Fatal error when talking to backend");
 541         do_close(assoc, Z_Close_systemProblem, 0);
 542         iochan_destroy(i);
 543         return;
 544     }
 545     else if (!res) /* no result yet - try again later */
 546     {
 547         logf(LOG_DEBUG, "   no result yet");
 548         iochan_setfd(i, fd); /* in case fd has changed */
 549     }
 550 }
 551
 552 /*
 553  * Encode response, and transfer the request structure to the outgoing queue.
 554  */
 555 static int process_response(association *assoc, request *req, Z_APDU *res)
 556 {
 557     odr_setbuf(assoc->encode, req->response, req->size_response, 1);
 558     if (!z_APDU(assoc->encode, &res, 0))
 559     {
 560         logf(LOG_WARN, "ODR error when encoding response: %s",
 561             odr_errlist[odr_geterror(assoc->decode)]);
 562         return -1;
 563     }
 564     req->response = odr_getbuf(assoc->encode, &req->len_response,
 565         &req->size_response);
 566     odr_setbuf(assoc->encode, 0, 0, 0); /* don't free if we abort later */
 567     odr_reset(assoc->encode);
 568     if (assoc->print && !z_APDU(assoc->print, &res, 0))
 569     {
 570         logf(LOG_WARN, "ODR print error: %s",
 571             odr_errlist[odr_geterror(assoc->print)]);
 572         odr_reset(assoc->print);
 573     }
 574     /* change this when we make the backend reentrant */
 575     if (req == request_head(&assoc->incoming))
 576     {
 577         req->state = REQUEST_IDLE;
 578         request_deq(&assoc->incoming);
 579     }
 580     request_enq(&assoc->outgoing, req);
 581     /* turn the work over to the ir_session handler */
 582     iochan_setflag(assoc->client_chan, EVENT_OUTPUT);
 583     /* Is there more work to be done? give that to the input handler too */
 584     if (request_head(&assoc->incoming))
 585         iochan_setevent(assoc->client_chan, EVENT_WORK);
 586     return 0;
 587 }
 588
 589 /*
 590  * Handle init request.
 591  * At the moment, we don't check the options
 592  * anywhere else in the code - we just try not to do anything that would
 593  * break a naive client. We'll toss 'em into the association block when
 594  * we need them there.
 595  */
 596 static Z_APDU *process_initRequest(association *assoc, request *reqb)
 597 {
 598     Z_InitRequest *req = reqb->request->u.initRequest;
 599     Z_APDU *apdu = zget_APDU(assoc->encode, Z_APDU_initResponse);
 600     Z_InitResponse *resp = apdu->u.initResponse;
 601     bend_initrequest binitreq;
 602     bend_initresult *binitres;
 603     char options[100];
 604
 605     logf(LOG_LOG, "Got initRequest");
 606     if (req->implementationId)
 607         logf(LOG_LOG, "Id:        %s", req->implementationId);
 608     if (req->implementationName)
 609         logf(LOG_LOG, "Name:      %s", req->implementationName);
 610     if (req->implementationVersion)
 611         logf(LOG_LOG, "Version:   %s", req->implementationVersion);
 612
 613     binitreq.configname = "default-config";
 614     binitreq.auth = req->idAuthentication;
 615     if (!(binitres = bend_init(&binitreq)))
 616     {
 617         logf(LOG_WARN, "Bad response from backend.");
 618         return 0;
 619     }
 620
 621     assoc->backend = binitres->handle;
 622     resp->referenceId = req->referenceId;
 623     *options = '\0';
 624     /* let's tell the client what we can do */
 625     if (ODR_MASK_GET(req->options, Z_Options_search))
 626     {
 627         ODR_MASK_SET(resp->options, Z_Options_search);
 628         strcat(options, "srch");
 629     }
 630     if (ODR_MASK_GET(req->options, Z_Options_present))
 631     {
 632         ODR_MASK_SET(resp->options, Z_Options_present);
 633         strcat(options, " prst");
 634     }
 635 #if 0
 636     if (ODR_MASK_GET(req->options, Z_Options_delSet))
 637     {
 638         ODR_MASK_SET(&options, Z_Options_delSet);
 639         strcat(options, " del");
 640     }
 641 #endif
 642     if (ODR_MASK_GET(req->options, Z_Options_namedResultSets))
 643     {
 644         ODR_MASK_SET(resp->options, Z_Options_namedResultSets);
 645         strcat(options, " namedresults");
 646     }
 647     if (ODR_MASK_GET(req->options, Z_Options_scan))
 648     {
 649         ODR_MASK_SET(resp->options, Z_Options_scan);
 650         strcat(options, " scan");
 651     }
 652     if (ODR_MASK_GET(req->options, Z_Options_concurrentOperations))
 653     {
 654         ODR_MASK_SET(resp->options, Z_Options_concurrentOperations);
 655         strcat(options, " concurop");
 656     }
 657
 658     if (ODR_MASK_GET(req->protocolVersion, Z_ProtocolVersion_1))
 659     {
 660         ODR_MASK_SET(resp->protocolVersion, Z_ProtocolVersion_1);
 661         assoc->version = 2; /* 1 & 2 are equivalent */
 662     }
 663     if (ODR_MASK_GET(req->protocolVersion, Z_ProtocolVersion_2))
 664     {
 665         ODR_MASK_SET(resp->protocolVersion, Z_ProtocolVersion_2);
 666         assoc->version = 2;
 667     }
 668     if (ODR_MASK_GET(req->protocolVersion, Z_ProtocolVersion_3))
 669     {
 670         ODR_MASK_SET(resp->protocolVersion, Z_ProtocolVersion_3);
 671         assoc->version = 3;
 672     }
 673     logf(LOG_LOG, "Negotiated to v%d: %s", assoc->version, options);
 674     assoc->maximumRecordSize = *req->maximumRecordSize;
 675     if (assoc->maximumRecordSize > control_block->maxrecordsize)
 676         assoc->maximumRecordSize = control_block->maxrecordsize;
 677     assoc->preferredMessageSize = *req->preferredMessageSize;
 678     if (assoc->preferredMessageSize > assoc->maximumRecordSize)
 679         assoc->preferredMessageSize = assoc->maximumRecordSize;
 680     resp->preferredMessageSize = &assoc->preferredMessageSize;
 681     resp->maximumRecordSize = &assoc->maximumRecordSize;
 682     resp->implementationName = "Index Data/YAZ Generic Frontend Server";
 683     if (binitres->errcode)
 684     {
 685         logf(LOG_LOG, "Connection rejected by backend.");
 686         *resp->result = 0;
 687         assoc->state = ASSOC_DEAD;
 688     }
 689     else
 690         assoc->state = ASSOC_UP;
 691     return apdu;
 692 }
 693
 694 /*
 695  * These functions should be merged.
 696  */
 697
 698 /*
 699  * nonsurrogate diagnostic record.
 700  */
 701 static Z_Records *diagrec(oid_proto proto, int error, char *addinfo)
 702 {
 703     static Z_Records rec;
 704     oident bib1;
 705     static int err;
 706 #ifdef Z_95
 707     static Z_DiagRec drec;
 708     static Z_DefaultDiagFormat dr;
 709 #else
 710     static Z_DiagRec dr;
 711 #endif
 712
 713     bib1.proto = proto;
 714     bib1.class = CLASS_DIAGSET;
 715     bib1.value = VAL_BIB1;
 716
 717     logf(LOG_DEBUG, "Diagnostic: %d -- %s", error, addinfo ? addinfo :
 718         "NULL");
 719     err = error;
 720     rec.which = Z_Records_NSD;
 721 #ifdef Z_95
 722     rec.u.nonSurrogateDiagnostic = &drec;
 723     drec.which = Z_DiagRec_defaultFormat;
 724     drec.u.defaultFormat = &dr;
 725 #else
 726     rec.u.nonSurrogateDiagnostic = &dr;
 727 #endif
 728     dr.diagnosticSetId = oid_getoidbyent(&bib1);
 729     dr.condition = &err;
 730     dr.which = Z_DiagForm_v2AddInfo;
 731     dr.addinfo = addinfo ? addinfo : "";
 732     return &rec;
 733 }
 734
 735 /*
 736  * surrogate diagnostic.
 737  */
 738 static Z_NamePlusRecord *surrogatediagrec(oid_proto proto, char *dbname,
 739                                             int error, char *addinfo)
 740 {
 741     static Z_NamePlusRecord rec;
 742     static int err;
 743     oident bib1;
 744 #ifdef Z_95
 745     static Z_DiagRec drec;
 746     static Z_DefaultDiagFormat dr;
 747 #else
 748     static Z_DiagRec dr;
 749 #endif
 750
 751     bib1.proto = proto;
 752     bib1.class = CLASS_DIAGSET;
 753     bib1.value = VAL_BIB1;
 754
 755     logf(LOG_DEBUG, "SurrogateDiagnotic: %d -- %s", error, addinfo);
 756     err = error;
 757     rec.databaseName = dbname;
 758     rec.which = Z_NamePlusRecord_surrogateDiagnostic;
 759 #ifdef Z_95
 760     rec.u.surrogateDiagnostic = &drec;
 761     drec.which = Z_DiagRec_defaultFormat;
 762     drec.u.defaultFormat = &dr;
 763 #else
 764     rec.u.surrogateDiagnostic = &dr;
 765 #endif
 766     dr.diagnosticSetId = oid_getoidbyent(&bib1);
 767     dr.condition = &err;
 768     dr.which = Z_DiagForm_v2AddInfo;
 769     dr.addinfo = addinfo ? addinfo : "";
 770     return &rec;
 771 }
 772
 773 /*
 774  * multiple nonsurrogate diagnostics.
 775  */
 776 static Z_DiagRecs *diagrecs(oid_proto proto, int error, char *addinfo)
 777 {
 778     static Z_DiagRecs recs;
 779     static int err;
 780     oident bib1;
 781 #ifdef Z_95
 782     static Z_DiagRec *recp[1], drec;
 783     static Z_DefaultDiagFormat rec;
 784 #else
 785     static Z_DiagRec *recp[1], rec;
 786 #endif
 787
 788     logf(LOG_DEBUG, "DiagRecs: %d -- %s", error, addinfo);
 789     bib1.proto = proto;
 790     bib1.class = CLASS_DIAGSET;
 791     bib1.value = VAL_BIB1;
 792
 793     err = error;
 794     recs.num_diagRecs = 1;
 795     recs.diagRecs = recp;
 796 #ifdef Z_95
 797     recp[0] = &drec;
 798     drec.which = Z_DiagRec_defaultFormat;
 799     drec.u.defaultFormat = &rec;
 800 #else
 801     recp[0] = &rec;
 802 #endif
 803     rec.diagnosticSetId = oid_getoidbyent(&bib1);
 804     rec.condition = &err;
 805     rec.which = Z_DiagForm_v2AddInfo;
 806     rec.addinfo = addinfo ? addinfo : "";
 807     return &recs;
 808 }
 809
 810 #define MAX_RECORDS 256
 811
 812 static Z_Records *pack_records(association *a, char *setname, int start,
 813                                 int *num, Z_RecordComposition *comp,
 814                                 int *next, int *pres, oid_value format)
 815 {
 816     int recno, total_length = 0, toget = *num;
 817     static Z_Records records;
 818     static Z_NamePlusRecordList reclist;
 819     static Z_NamePlusRecord *list[MAX_RECORDS];
 820     oident recform;
 821
 822     records.which = Z_Records_DBOSD;
 823     records.u.databaseOrSurDiagnostics = &reclist;
 824     reclist.num_records = 0;
 825     reclist.records = list;
 826     *pres = Z_PRES_SUCCESS;
 827     *num = 0;
 828     *next = 0;
 829
 830     logf(LOG_DEBUG, "Request to pack %d+%d", start, toget);
 831     logf(LOG_DEBUG, "pms=%d, mrs=%d", a->preferredMessageSize,
 832         a->maximumRecordSize);
 833     for (recno = start; reclist.num_records < toget; recno++)
 834     {
 835         bend_fetchrequest freq;
 836         bend_fetchresult *fres;
 837         Z_NamePlusRecord *thisrec;
 838         Z_DatabaseRecord *thisext;
 839         int this_length;
 840
 841         /*
 842          * we get the number of bytes allocated on the stream before any
 843          * allocation done by the backend - this should give us a reasonable
 844          * idea of the total size of the data so far.
 845          */
 846         total_length = odr_total(a->encode);
 847         if (reclist.num_records == MAX_RECORDS - 1)
 848         {
 849             *pres = Z_PRES_PARTIAL_2;
 850             break;
 851         }
 852         freq.setname = setname;
 853         freq.number = recno;
 854         freq.comp = comp;
 855         freq.format = format;
 856         freq.stream = a->encode;
 857         if (!(fres = bend_fetch(a->backend, &freq, 0)))
 858         {
 859             *pres = Z_PRES_FAILURE;
 860             return diagrec(a->proto, 2, "Backend interface problem");
 861         }
 862         /* backend should be able to signal whether error is system-wide
 863            or only pertaining to current record */
 864         if (fres->errcode)
 865         {
 866             *pres = Z_PRES_FAILURE;
 867             return diagrec(a->proto, fres->errcode, fres->errstring);
 868         }
 869         if (fres->len >= 0)
 870             this_length = fres->len;
 871         else
 872             this_length = odr_total(a->encode) - total_length;
 873         logf(LOG_DEBUG, "  fetched record, len=%d, total=%d",
 874             this_length, total_length);
 875         if (this_length + total_length > a->preferredMessageSize)
 876         {
 877             /* record is small enough, really */
 878             if (this_length <= a->preferredMessageSize)
 879             {
 880                 logf(LOG_DEBUG, "  Dropped last normal-sized record");
 881                 *pres = Z_PRES_PARTIAL_2;
 882                 break;
 883             }
 884             /* record can only be fetched by itself */
 885             if (this_length < a->maximumRecordSize)
 886             {
 887                 logf(LOG_DEBUG, "  Record > prefmsgsz");
 888                 if (toget > 1)
 889                 {
 890                     logf(LOG_DEBUG, "  Dropped it");
 891                     reclist.records[reclist.num_records] =
 892                          surrogatediagrec(a->proto, fres->basename, 16, 0);
 893                     reclist.num_records++;
 894                     continue;
 895                 }
 896             }
 897             else /* too big entirely */
 898             {
 899                 logf(LOG_DEBUG, "Record > maxrcdsz");
 900                 reclist.records[reclist.num_records] =
 901                     surrogatediagrec(a->proto, fres->basename, 17, 0);
 902                 reclist.num_records++;
 903                 continue;
 904             }
 905         }
 906         if (!(thisrec = odr_malloc(a->encode, sizeof(*thisrec))))
 907             return 0;
 908         if (!(thisrec->databaseName = odr_malloc(a->encode,
 909             strlen(fres->basename) + 1)))
 910             return 0;
 911         strcpy(thisrec->databaseName, fres->basename);
 912         thisrec->which = Z_NamePlusRecord_databaseRecord;
 913         if (!(thisrec->u.databaseRecord = thisext = odr_malloc(a->encode,
 914             sizeof(Z_DatabaseRecord))))
 915             return 0;
 916         recform.proto = a->proto;
 917         recform.class = CLASS_RECSYN;
 918         recform.value = fres->format;
 919         thisext->direct_reference = odr_oiddup(a->encode,
 920             oid_getoidbyent(&recform));
 921         thisext->indirect_reference = 0;
 922         thisext->descriptor = 0;
 923         if (fres->len < 0) /* Structured data */
 924         {
 925             switch (fres->format)
 926             {
 927                 case VAL_SUTRS: thisext->which = Z_External_sutrs; break;
 928                 case VAL_GRS1: thisext->which = Z_External_grs1; break;
 929                 case VAL_EXPLAIN: thisext->which = Z_External_explainRecord;
 930                     break;
 931
 932                 default:
 933                     logf(LOG_FATAL, "Unknown structured format from backend.");
 934                     return 0;
 935             }
 936
 937             /*
 938              * We cheat on the pointers here. Obviously, the record field
 939              * of the backend-fetch structure should have been a union for
 940              * correctness, but we're stuck with this for backwards
 941              * compatibility.
 942              */
 943             thisext->u.grs1 = (Z_GenericRecord*) fres->record;
 944         }
 945         else if (fres->format == VAL_SUTRS) /* SUTRS is a single-ASN.1-type */
 946         {
 947             Odr_oct *sutrs = odr_malloc(a->encode, sizeof(*sutrs));
 948
 949             thisext->which = Z_External_sutrs;
 950             thisext->u.sutrs = sutrs;
 951             sutrs->buf = odr_malloc(a->encode, fres->len);
 952             sutrs->len = sutrs->size = fres->len;
 953             memcpy(sutrs->buf, fres->record, fres->len);
 954         }
 955         else /* octet-aligned record. */
 956         {
 957             thisext->which = Z_External_octet;
 958             if (!(thisext->u.octet_aligned = odr_malloc(a->encode,
 959                 sizeof(Odr_oct))))
 960                 return 0;
 961             if (!(thisext->u.octet_aligned->buf = odr_malloc(a->encode,
 962                 fres->len)))
 963                 return 0;
 964             memcpy(thisext->u.octet_aligned->buf, fres->record, fres->len);
 965             thisext->u.octet_aligned->len = thisext->u.octet_aligned->size =
 966                 fres->len;
 967         }
 968         reclist.records[reclist.num_records] = thisrec;
 969         reclist.num_records++;
 970         *next = fres->last_in_set ? 0 : recno + 1;
 971     }
 972     *num = reclist.num_records;
 973     return &records;
 974 }
 975
 976 static Z_APDU *process_searchRequest(association *assoc, request *reqb,
 977     int *fd)
 978 {
 979     Z_SearchRequest *req = reqb->request->u.searchRequest;
 980     bend_searchrequest bsrq;
 981     bend_searchresult *bsrt;
 982
 983     logf(LOG_LOG, "Got SearchRequest.");
 984
 985     bsrq.setname = req->resultSetName;
 986     bsrq.replace_set = *req->replaceIndicator;
 987     bsrq.num_bases = req->num_databaseNames;
 988     bsrq.basenames = req->databaseNames;
 989     bsrq.query = req->query;
 990
 991     if (!(bsrt = bend_search(assoc->backend, &bsrq, fd)))
 992         return 0;
 993     return response_searchRequest(assoc, reqb, bsrt, fd);
 994 }
 995
 996 bend_searchresult *bend_searchresponse(void *handle) {return 0;}
 997
 998 /*
 999  * Prepare a searchresponse based on the backend results. We probably want
1000  * to look at making the fetching of records nonblocking as well, but
1001  * so far, we'll keep things simple.
1002  * If bsrt is null, that means we're called in response to a communications
1003  * event, and we'll have to get the response for ourselves.
1004  */
1005 static Z_APDU *response_searchRequest(association *assoc, request *reqb,
1006     bend_searchresult *bsrt, int *fd)
1007 {
1008     Z_SearchRequest *req = reqb->request->u.searchRequest;
1009     static Z_APDU apdu;
1010     static Z_SearchResponse resp;
1011     static int nulint = 0;
1012     static bool_t sr = 1;
1013     static int next = 0;
1014     static int none = Z_RES_NONE;
1015
1016     apdu.which = Z_APDU_searchResponse;
1017     apdu.u.searchResponse = &resp;
1018     resp.referenceId = req->referenceId;
1019 #ifdef Z_95
1020     resp.additionalSearchInfo = 0;
1021     resp.otherInfo = 0;
1022 #endif
1023     *fd = -1;
1024     if (!bsrt && !(bsrt = bend_searchresponse(assoc->backend)))
1025     {
1026         logf(LOG_FATAL, "Bad result from backend");
1027         return 0;
1028     }
1029     else if (bsrt->errcode)
1030     {
1031         resp.records = diagrec(assoc->proto, bsrt->errcode,
1032             bsrt->errstring);
1033         resp.resultCount = &nulint;
1034         resp.numberOfRecordsReturned = &nulint;
1035         resp.nextResultSetPosition = &nulint;
1036         resp.searchStatus = &nulint;
1037         resp.resultSetStatus = &none;
1038         resp.presentStatus = 0;
1039     }
1040     else
1041     {
1042         static int toget;
1043         Z_RecordComposition comp;
1044         static int presst = 0;
1045
1046         resp.records = 0;
1047         resp.resultCount = &bsrt->hits;
1048
1049         comp.which = Z_RecordComp_simple;
1050         /* how many records does the user agent want, then? */
1051         if (bsrt->hits <= *req->smallSetUpperBound)
1052         {
1053             toget = bsrt->hits;
1054             comp.u.simple = req->smallSetElementSetNames;
1055         }
1056         else if (bsrt->hits < *req->largeSetLowerBound)
1057         {
1058             toget = *req->mediumSetPresentNumber;
1059             if (toget > bsrt->hits)
1060                 toget = bsrt->hits;
1061             comp.u.simple = req->mediumSetElementSetNames;
1062         }
1063         else
1064             toget = 0;
1065
1066         if (toget && !resp.records)
1067         {
1068             oident *prefformat;
1069             oid_value form;
1070
1071             if (!(prefformat = oid_getentbyoid(req->preferredRecordSyntax)) ||
1072                 prefformat->class != CLASS_RECSYN)
1073                 form = VAL_NONE;
1074             else
1075                 form = prefformat->value;
1076             resp.records = pack_records(assoc, req->resultSetName, 1,
1077                 &toget, &comp, &next, &presst, form);
1078             if (!resp.records)
1079                 return 0;
1080             resp.numberOfRecordsReturned = &toget;
1081             resp.nextResultSetPosition = &next;
1082             resp.searchStatus = &sr;
1083             resp.resultSetStatus = 0;
1084             resp.presentStatus = &presst;
1085         }
1086         else
1087         {
1088             if (*resp.resultCount)
1089                 next = 1;
1090             resp.numberOfRecordsReturned = &nulint;
1091             resp.nextResultSetPosition = &next;
1092             resp.searchStatus = &sr;
1093             resp.resultSetStatus = 0;
1094             resp.presentStatus = 0;
1095         }
1096     }
1097     return &apdu;
1098 }
1099
1100 /*
1101  * Maybe we got a little over-friendly when we designed bend_fetch to
1102  * get only one record at a time. Some backends can optimise multiple-record
1103  * fetches, and at any rate, there is some overhead involved in
1104  * all that selecting and hopping around. Problem is, of course, that the
1105  * frontend can't know ahead of time how many records it'll need to
1106  * fill the negotiated PDU size. Annoying. Segmentation or not, Z/SR
1107  * is downright lousy as a bulk data transfer protocol.
1108  *
1109  * To start with, we'll do the fetching of records from the backend
1110  * in one operation: To save some trips in and out of the event-handler,
1111  * and to simplify the interface to pack_records. At any rate, asynch
1112  * operation is more fun in operations that have an unpredictable execution
1113  * speed - which is normally more true for search than for present.
1114  */
1115 static Z_APDU *process_presentRequest(association *assoc, request *reqb,
1116     int *fd)
1117 {
1118     Z_PresentRequest *req = reqb->request->u.presentRequest;
1119     static Z_APDU apdu;
1120     static Z_PresentResponse resp;
1121     static int presst, next, num;
1122     oident *prefformat;
1123     oid_value form;
1124
1125
1126     logf(LOG_LOG, "Got PresentRequest.");
1127     apdu.which = Z_APDU_presentResponse;
1128     apdu.u.presentResponse = &resp;
1129     resp.referenceId = req->referenceId;
1130 #ifdef Z_95
1131     resp.otherInfo = 0;
1132 #endif
1133
1134     if (!(prefformat = oid_getentbyoid(req->preferredRecordSyntax)) ||
1135         prefformat->class != CLASS_RECSYN)
1136         form = VAL_NONE;
1137     else
1138         form = prefformat->value;
1139     num = *req->numberOfRecordsRequested;
1140     resp.records = pack_records(assoc, req->resultSetId,
1141         *req->resultSetStartPoint, &num, req->recordComposition, &next,
1142         &presst, form);
1143     if (!resp.records)
1144         return 0;
1145     resp.numberOfRecordsReturned = &num;
1146     resp.presentStatus = &presst;
1147     resp.nextResultSetPosition = &next;
1148
1149     return &apdu;
1150 }
1151
1152 /*
1153  * Scan was implemented rather in a hurry, and with support for only the basic
1154  * elements of the service in the backend API. Suggestions are welcome.
1155  */
1156 static Z_APDU *process_scanRequest(association *assoc, request *reqb, int *fd)
1157 {
1158     Z_ScanRequest *req = reqb->request->u.scanRequest;
1159     static Z_APDU apdu;
1160     static Z_ScanResponse res;
1161     static int scanStatus = Z_Scan_failure;
1162     static int numberOfEntriesReturned = 0;
1163     oident *attent;
1164     static Z_ListEntries ents;
1165 #define SCAN_MAX_ENTRIES 200
1166     static Z_Entry *tab[SCAN_MAX_ENTRIES];
1167     bend_scanrequest srq;
1168     bend_scanresult *srs;
1169
1170     logf(LOG_LOG, "Got scanrequest");
1171     apdu.which = Z_APDU_scanResponse;
1172     apdu.u.scanResponse = &res;
1173     res.referenceId = req->referenceId;
1174     res.stepSize = 0;
1175     res.scanStatus = &scanStatus;
1176     res.numberOfEntriesReturned = &numberOfEntriesReturned;
1177     res.positionOfTerm = 0;
1178     res.entries = &ents;
1179     ents.which = Z_ListEntries_nonSurrogateDiagnostics;
1180     res.attributeSet = 0;
1181 #ifdef Z_95
1182     res.otherInfo = 0;
1183 #endif
1184
1185     if (req->attributeSet && (!(attent = oid_getentbyoid(req->attributeSet)) ||
1186         attent->class != CLASS_ATTSET || attent->value != VAL_BIB1))
1187         ents.u.nonSurrogateDiagnostics = diagrecs(assoc->proto, 121, 0);
1188     else if (req->stepSize && *req->stepSize > 0)
1189         ents.u.nonSurrogateDiagnostics = diagrecs(assoc->proto, 205, 0);
1190     else
1191     {
1192         if (req->termListAndStartPoint->term->which == Z_Term_general)
1193             logf(LOG_DEBUG, " term: '%.*s'",
1194                 req->termListAndStartPoint->term->u.general->len,
1195                 req->termListAndStartPoint->term->u.general->buf);
1196         srq.num_bases = req->num_databaseNames;
1197         srq.basenames = req->databaseNames;
1198         srq.num_entries = *req->numberOfTermsRequested;
1199         srq.term = req->termListAndStartPoint;
1200         srq.term_position = req->preferredPositionInResponse ?
1201             *req->preferredPositionInResponse : 1;
1202         if (!(srs = bend_scan(assoc->backend, &srq, 0)))
1203             ents.u.nonSurrogateDiagnostics = diagrecs(assoc->proto, 2, 0);
1204         else if (srs->errcode)
1205             ents.u.nonSurrogateDiagnostics = diagrecs(assoc->proto,
1206                 srs->errcode, srs->errstring);
1207         else
1208         {
1209             int i;
1210             static Z_Entries list;
1211
1212             if (srs->status == BEND_SCAN_PARTIAL)
1213                 scanStatus = Z_Scan_partial_5;
1214             else
1215                 scanStatus = Z_Scan_success;
1216             ents.which = Z_ListEntries_entries;
1217             ents.u.entries = &list;
1218             list.entries = tab;
1219             for (i = 0; i < srs->num_entries; i++)
1220             {
1221                 Z_Entry *e;
1222                 Z_TermInfo *t;
1223                 Odr_oct *o;
1224
1225                 if (i >= SCAN_MAX_ENTRIES)
1226                 {
1227                     scanStatus = Z_Scan_partial_4;
1228                     break;
1229                 }
1230                 list.entries[i] = e = odr_malloc(assoc->encode, sizeof(*e));
1231                 e->which = Z_Entry_termInfo;
1232                 e->u.termInfo = t = odr_malloc(assoc->encode, sizeof(*t));
1233                 t->suggestedAttributes = 0;
1234                 t->alternativeTerm = 0;
1235                 t->byAttributes = 0;
1236                 t->globalOccurrences = &srs->entries[i].occurrences;
1237                 t->term = odr_malloc(assoc->encode, sizeof(*t->term));
1238                 t->term->which = Z_Term_general;
1239                 t->term->u.general = o = odr_malloc(assoc->encode,
1240                     sizeof(Odr_oct));
1241                 o->buf = odr_malloc(assoc->encode, o->len = o->size =
1242                     strlen(srs->entries[i].term));
1243                 memcpy(o->buf, srs->entries[i].term, o->len);
1244                 logf(LOG_DEBUG, "  term #%d: '%s' (%d)", i,
1245                     srs->entries[i].term, srs->entries[i].occurrences);
1246             }
1247             list.num_entries = i;
1248             res.numberOfEntriesReturned = &list.num_entries;
1249             res.positionOfTerm = &srs->term_position;
1250         }
1251     }
1252
1253     return &apdu;
1254 }
1255
1256 static void process_close(association *assoc, request *reqb)
1257 {
1258     Z_Close *req = reqb->request->u.close;
1259     static char *reasons[] =
1260     {
1261         "finished",
1262         "shutdown",
1263         "systemProblem",
1264         "costLimit",
1265         "resources",
1266         "securityViolation",
1267         "protocolError",
1268         "lackOfActivity",
1269         "peerAbort",
1270         "unspecified"
1271     };
1272
1273     logf(LOG_LOG, "Got close, reason %s, message %s",
1274         reasons[*req->closeReason], req->diagnosticInformation ?
1275         req->diagnosticInformation : "NULL");
1276     if (assoc->version < 3) /* to make do_force respond with close */
1277         assoc->version = 3;
1278     do_close(assoc, Z_Close_finished, "Association terminated by client");
1279 }