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