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 1.43  1995-08-15 12:00:31  quinn
   8  * Updated External
   9  *
  10  * Revision 1.42  1995/08/15  11:16:50  quinn
  11  * CV:e ----------------------------------------------------------------------
  12  * CV:e ----------------------------------------------------------------------
  13  *
  14  * Revision 1.41  1995/08/02  10:23:06  quinn
  15  * Smallish
  16  *
  17  * Revision 1.40  1995/07/31  14:34:26  quinn
  18  * Fixed bug in process_searchResponse (numberOfRecordsReturned).
  19  *
  20  * Revision 1.39  1995/06/27  13:21:00  quinn
  21  * SUTRS support
  22  *
  23  * Revision 1.38  1995/06/19  12:39:11  quinn
  24  * Fixed bug in timeout code. Added BER dumper.
  25  *
  26  * Revision 1.37  1995/06/16  13:16:14  quinn
  27  * Fixed Defaultdiagformat.
  28  *
  29  * Revision 1.36  1995/06/16  10:31:36  quinn
  30  * Added session timeout.
  31  *
  32  * Revision 1.35  1995/06/15  07:45:14  quinn
  33  * Moving to v3.
  34  *
  35  * Revision 1.34  1995/06/14  15:26:46  quinn
  36  * *** empty log message ***
  37  *
  38  * Revision 1.33  1995/06/06  14:57:05  quinn
  39  * Better diagnostics.
  40  *
  41  * Revision 1.32  1995/06/06  08:41:44  quinn
  42  * Better diagnostics.
  43  *
  44  * Revision 1.31  1995/06/06  08:15:37  quinn
  45  * Cosmetic.
  46  *
  47  * Revision 1.30  1995/06/05  10:53:32  quinn
  48  * Added a better SCAN.
  49  *
  50  * Revision 1.29  1995/06/01  11:25:03  quinn
  51  * Smallish.
  52  *
  53  * Revision 1.28  1995/06/01  11:21:01  quinn
  54  * Attempting to fix a bug in pack-records. replaced break with continue
  55  * for large records, according to standard.
  56  *
  57  * Revision 1.27  1995/05/29  08:12:06  quinn
  58  * Moved oid to util
  59  *
  60  * Revision 1.26  1995/05/18  13:02:12  quinn
  61  * Smallish.
  62  *
  63  * Revision 1.25  1995/05/17  08:42:26  quinn
  64  * Transfer auth info to backend. Allow backend to reject init gracefully.
  65  *
  66  * Revision 1.24  1995/05/16  08:51:04  quinn
  67  * License, documentation, and memory fixes
  68  *
  69  * Revision 1.23  1995/05/15  13:25:10  quinn
  70  * Fixed memory bug.
  71  *
  72  * Revision 1.22  1995/05/15  11:56:39  quinn
  73  * Asynchronous facilities. Restructuring of seshigh code.
  74  *
  75  * Revision 1.21  1995/05/02  08:53:19  quinn
  76  * Trying in vain to fix comm with ISODE
  77  *
  78  * Revision 1.20  1995/04/20  15:13:00  quinn
  79  * Cosmetic
  80  *
  81  * Revision 1.19  1995/04/18  08:15:34  quinn
  82  * Added dynamic memory allocation on encoding (whew). Code is now somewhat
  83  * neater. We'll make the same change for decoding one day.
  84  *
  85  * Revision 1.18  1995/04/17  11:28:25  quinn
  86  * Smallish
  87  *
  88  * Revision 1.17  1995/04/10  10:23:36  quinn
  89  * Some work to add scan and other things.
  90  *
  91  * Revision 1.16  1995/03/31  09:18:55  quinn
  92  * Added logging.
  93  *
  94  * Revision 1.15  1995/03/30  14:03:23  quinn
  95  * Added RFC1006 as separate library
  96  *
  97  * Revision 1.14  1995/03/30  12:18:17  quinn
  98  * Fixed bug.
  99  *
 100  * Revision 1.13  1995/03/30  09:09:24  quinn
 101  * Added state-handle and some support for asynchronous activities.
 102  *
 103  * Revision 1.12  1995/03/29  15:40:16  quinn
 104  * Ongoing work. Statserv is now dynamic by default
 105  *
 106  * Revision 1.11  1995/03/28  09:16:21  quinn
 107  * Added record packing to the search request
 108  *
 109  * Revision 1.10  1995/03/27  08:34:24  quinn
 110  * Added dynamic server functionality.
 111  * Released bindings to session.c (is now redundant)
 112  *
 113  * Revision 1.9  1995/03/22  15:01:26  quinn
 114  * Adjusting record packing.
 115  *
 116  * Revision 1.8  1995/03/22  10:13:21  quinn
 117  * Working on record packer
 118  *
 119  * Revision 1.7  1995/03/21  15:53:31  quinn
 120  * Little changes.
 121  *
 122  * Revision 1.6  1995/03/21  12:30:09  quinn
 123  * Beginning to add support for record packing.
 124  *
 125  * Revision 1.5  1995/03/17  10:44:13  quinn
 126  * Added catch of null-string in makediagrec
 127  *
 128  * Revision 1.4  1995/03/17  10:18:08  quinn
 129  * Added memory management.
 130  *
 131  * Revision 1.3  1995/03/16  17:42:39  quinn
 132  * Little changes
 133  *
 134  * Revision 1.2  1995/03/16  13:29:01  quinn
 135  * Partitioned server.
 136  *
 137  * Revision 1.1  1995/03/15  16:02:10  quinn
 138  * Modded session.c to seshigh.c
 139  *
 140  */
 141
 142 /*
 143  * Frontend server logic.
 144  *
 145  * This code receives incoming APDUs, and handles client requests by means
 146  * of the backend API.
 147  *
 148  * Some of the code is getting quite involved, compared to simpler servers -
 149  * primarily because it is asynchronous both in the communication with
 150  * the user and the backend. We think the complexity will pay off in
 151  * the form of greater flexibility when more asynchronous facilities
 152  * are implemented.
 153  *
 154  * Memory management has become somewhat involved. In the simple case, where
 155  * only one PDU is pending at a time, it will simply reuse the same memory,
 156  * once it has found its working size. When we enable multiple concurrent
 157  * operations, perhaps even with multiple parallel calls to the backend, it
 158  * will maintain a pool of buffers for encoding and decoding, trying to
 159  * minimize memory allocation/deallocation during normal operation.
 160  *
 161  * TODOs include (and will be done in order of public interest):
 162  *
 163  * Support for EXPLAIN - provide simple meta-database system.
 164  * Support for access control.
 165  * Support for resource control.
 166  * Support for extended services - primarily Item Order.
 167  * Rest of Z39.50-1994
 168  *
 169  */
 170
 171 #include <stdlib.h>
 172 #include <stdio.h>
 173 #include <unistd.h>
 174 #include <assert.h>
 175
 176 #include <dmalloc.h>
 177 #include <comstack.h>
 178 #include <eventl.h>
 179 #include <session.h>
 180 #include <proto.h>
 181 #include <oid.h>
 182 #include <log.h>
 183 #include <statserv.h>
 184
 185 #include <backend.h>
 186
 187 static int process_request(association *assoc);
 188 void backend_response(IOCHAN i, int event);
 189 static int process_response(association *assoc, request *req, Z_APDU *res);
 190 static Z_APDU *process_initRequest(association *assoc, request *reqb);
 191 static Z_APDU *process_searchRequest(association *assoc, request *reqb,
 192     int *fd);
 193 static Z_APDU *response_searchRequest(association *assoc, request *reqb,
 194     bend_searchresult *bsrt, int *fd);
 195 static Z_APDU *process_presentRequest(association *assoc, request *reqb,
 196     int *fd);
 197 static Z_APDU *process_scanRequest(association *assoc, request *reqb, int *fd);
 198
 199 static FILE *apduf = 0; /* for use in static mode */
 200 static statserv_options_block *control_block = 0;
 201
 202 /*
 203  * Create and initialize a new association-handle.
 204  *  channel  : iochannel for the current line.
 205  *  link     : communications channel.
 206  * Returns: 0 or a new association handle.
 207  */
 208 association *create_association(IOCHAN channel, COMSTACK link)
 209 {
 210     association *new;
 211
 212     if (!control_block)
 213         control_block = statserv_getcontrol();
 214     if (!(new = malloc(sizeof(*new))))
 215         return 0;
 216     new->client_chan = channel;
 217     new->client_link = link;
 218     if (!(new->decode = odr_createmem(ODR_DECODE)) ||
 219         !(new->encode = odr_createmem(ODR_ENCODE)))
 220         return 0;
 221     if (*control_block->apdufile)
 222     {
 223         char filename[256];
 224         FILE *f;
 225
 226         strcpy(filename, control_block->apdufile);
 227         if (!(new->print = odr_createmem(ODR_PRINT)))
 228             return 0;
 229         if (*control_block->apdufile != '-')
 230         {
 231             strcpy(filename, control_block->apdufile);
 232             if (!control_block->dynamic)
 233             {
 234                 if (!apduf)
 235                 {
 236                     if (!(apduf = fopen(filename, "w")))
 237                     {
 238                         logf(LOG_WARN|LOG_ERRNO, "%s", filename);
 239                         return 0;
 240                     }
 241                     setvbuf(apduf, 0, _IONBF, 0);
 242                 }
 243                 f = apduf;
 244             }
 245             else
 246             {
 247                 sprintf(filename + strlen(filename), ".%d", getpid());
 248                 if (!(f = fopen(filename, "w")))
 249                 {
 250                     logf(LOG_WARN|LOG_ERRNO, "%s", filename);
 251                     return 0;
 252                 }
 253                 setvbuf(f, 0, _IONBF, 0);
 254             }
 255             odr_setprint(new->print, f);
 256         }
 257     }
 258     else
 259         new->print = 0;
 260     new->input_buffer = 0;
 261     new->input_buffer_len = 0;
 262     new->backend = 0;
 263     new->rejected = 0;
 264     request_initq(&new->incoming);
 265     request_initq(&new->outgoing);
 266     new->proto = cs_getproto(link);
 267     return new;
 268 }
 269
 270 /*
 271  * Free association and release resources.
 272  */
 273 void destroy_association(association *h)
 274 {
 275     odr_destroy(h->decode);
 276     odr_destroy(h->encode);
 277     if (h->print)
 278         odr_destroy(h->print);
 279     if (h->input_buffer)
 280         free(h->input_buffer);
 281     if (h->backend)
 282         bend_close(h->backend);
 283     while (request_deq(&h->incoming));
 284     while (request_deq(&h->outgoing));
 285     free(h);
 286 }
 287
 288 /*
 289  * This is where PDUs from the client are read and the further
 290  * processing is initiated. Flow of control moves down through the
 291  * various process_* functions below, until the encoded result comes back up
 292  * to the output handler in here.
 293  *
 294  *  h     : the I/O channel that has an outstanding event.
 295  *  event : the current outstanding event.
 296  */
 297 void ir_session(IOCHAN h, int event)
 298 {
 299     int res;
 300     association *assoc = iochan_getdata(h);
 301     COMSTACK conn = assoc->client_link;
 302     request *req;
 303
 304     assert(h && conn && assoc);
 305     if (event == EVENT_TIMEOUT)
 306     {
 307         logf(LOG_LOG, "Timeout - closing connection.");
 308         cs_close(conn);
 309         destroy_association(assoc);
 310         iochan_destroy(h);
 311         return;
 312     }
 313     if (event & EVENT_INPUT || event & EVENT_WORK) /* input */
 314     {
 315         if (event & EVENT_INPUT)
 316         {
 317             logf(LOG_DEBUG, "ir_session (input)");
 318             assert(assoc && conn);
 319             /* We aren't speaking to this fellow */
 320             if (assoc->rejected)
 321             {
 322                 logf(LOG_LOG, "Closed connection after reject");
 323                 cs_close(conn);
 324                 destroy_association(assoc);
 325                 iochan_destroy(h);
 326                 return;
 327             }
 328             if ((res = cs_get(conn, &assoc->input_buffer,
 329                 &assoc->input_buffer_len)) <= 0)
 330             {
 331                 logf(LOG_LOG, "Connection closed by client");
 332                 cs_close(conn);
 333                 destroy_association(assoc);
 334                 iochan_destroy(h);
 335                 return;
 336             }
 337             else if (res == 1) /* incomplete read - wait for more  */
 338                 return;
 339             if (cs_more(conn)) /* more stuff - call us again later, please */
 340                 iochan_setevent(h, EVENT_INPUT);
 341
 342             /* we got a complete PDU. Let's decode it */
 343             logf(LOG_DEBUG, "Got PDU, %d bytes", res);
 344             req = request_get(); /* get a new request structure */
 345             odr_reset(assoc->decode);
 346             odr_setbuf(assoc->decode, assoc->input_buffer, res, 0);
 347             if (!z_APDU(assoc->decode, &req->request, 0))
 348             {
 349                 logf(LOG_LOG, "ODR error on incoming PDU: %s",
 350                     odr_errlist[odr_geterror(assoc->decode)]);
 351                 logf(LOG_LOG, "PDU dump:");
 352                 odr_dumpBER(log_file(), assoc->input_buffer, res);
 353                 cs_close(conn);
 354                 destroy_association(assoc);
 355                 iochan_destroy(h);
 356                 return;
 357             }
 358             req->request_mem = odr_extract_mem(assoc->decode);
 359             if (assoc->print && !z_APDU(assoc->print, &req->request, 0))
 360             {
 361                 logf(LOG_WARN, "ODR print error: %s",
 362                     odr_errlist[odr_geterror(assoc->print)]);
 363                 odr_reset(assoc->print);
 364             }
 365             request_enq(&assoc->incoming, req);
 366         }
 367
 368         /* can we do something yet? */
 369         req = request_head(&assoc->incoming);
 370         if (req->state == REQUEST_IDLE)
 371             if (process_request(assoc) < 0)
 372             {
 373                 cs_close(conn);
 374                 destroy_association(assoc);
 375                 iochan_destroy(h);
 376             }
 377     }
 378     if (event & EVENT_OUTPUT)
 379     {
 380         request *req = request_head(&assoc->outgoing);
 381
 382         logf(LOG_DEBUG, "ir_session (output)");
 383         req->state = REQUEST_PENDING;
 384         switch (res = cs_put(conn, req->response, req->len_response))
 385         {
 386             case -1:
 387                 logf(LOG_LOG, "Connection closed by client");
 388                 cs_close(conn);
 389                 destroy_association(assoc);
 390                 iochan_destroy(h);
 391                 break;
 392             case 0: /* all sent - release the request structure */
 393                 logf(LOG_DEBUG, "Wrote PDU, %d bytes", req->len_response);
 394                 odr_release_mem(req->request_mem);
 395                 request_deq(&assoc->outgoing);
 396                 request_release(req);
 397                 if (!request_head(&assoc->outgoing))
 398                     iochan_clearflag(h, EVENT_OUTPUT);
 399                 break;
 400             /* value of 1 -- partial send -- is simply ignored */
 401         }
 402     }
 403     if (event & EVENT_EXCEPT)
 404     {
 405         logf(LOG_DEBUG, "ir_session (exception)");
 406         cs_close(conn);
 407         destroy_association(assoc);
 408         iochan_destroy(h);
 409     }
 410 }
 411
 412 /*
 413  * Initiate request processing.
 414  */
 415 static int process_request(association *assoc)
 416 {
 417     request *req = request_head(&assoc->incoming);
 418     int fd = -1;
 419     Z_APDU *res;
 420
 421     logf(LOG_DEBUG, "process_request");
 422     assert(req && req->state == REQUEST_IDLE);
 423     switch (req->request->which)
 424     {
 425         case Z_APDU_initRequest:
 426             res = process_initRequest(assoc, req); break;
 427         case Z_APDU_searchRequest:
 428             res = process_searchRequest(assoc, req, &fd); break;
 429         case Z_APDU_presentRequest:
 430             res = process_presentRequest(assoc, req, &fd); break;
 431         case Z_APDU_scanRequest:
 432             res = process_scanRequest(assoc, req, &fd); break;
 433         default:
 434             logf(LOG_WARN, "Bad APDU received");
 435             return -1;
 436     }
 437     if (res)
 438     {
 439         logf(LOG_DEBUG, "  result immediately available");
 440         return process_response(assoc, req, res);
 441     }
 442     else if (fd < 0)
 443     {
 444         logf(LOG_WARN, "   bad result");
 445         return -1;
 446     }
 447     else /* no result yet - one will be provided later */
 448     {
 449         IOCHAN chan;
 450
 451         /* Set up an I/O handler for the fd supplied by the backend */
 452
 453         logf(LOG_DEBUG, "   establishing handler for result");
 454         req->state = REQUEST_PENDING;
 455         if (!(chan = iochan_create(fd, backend_response, EVENT_INPUT)))
 456             abort();
 457         iochan_setdata(chan, assoc);
 458         return 0;
 459     }
 460 }
 461
 462 /*
 463  * Handle message from the backend.
 464  */
 465 void backend_response(IOCHAN i, int event)
 466 {
 467     association *assoc = iochan_getdata(i);
 468     request *req = request_head(&assoc->incoming);
 469     Z_APDU *res;
 470     int fd;
 471
 472     logf(LOG_DEBUG, "backend_response");
 473     assert(assoc && req && req->state != REQUEST_IDLE);
 474     /* determine what it is we're waiting for */
 475     switch (req->request->which)
 476     {
 477         case Z_APDU_searchRequest:
 478             res = response_searchRequest(assoc, req, 0, &fd); break;
 479 #if 0
 480         case Z_APDU_presentRequest:
 481             res = response_presentRequest(assoc, req, 0, &fd); break;
 482         case Z_APDU_scanRequest:
 483             res = response_scanRequest(assoc, req, 0, &fd); break;
 484 #endif
 485         default:
 486             logf(LOG_WARN, "Serious programmer's lapse or bug");
 487             abort();
 488     }
 489     if ((res && process_response(assoc, req, res) < 0) || fd < 0)
 490     {
 491         logf(LOG_LOG, "Fatal error when talking to backend");
 492         cs_close(assoc->client_link);
 493         destroy_association(assoc);
 494         iochan_destroy(assoc->client_chan);
 495         iochan_destroy(i);
 496         return;
 497     }
 498     else if (!res) /* no result yet - try again later */
 499     {
 500         logf(LOG_DEBUG, "   no result yet");
 501         iochan_setfd(i, fd); /* in case fd has changed */
 502     }
 503 }
 504
 505 /*
 506  * Encode response, and transfer the request structure to the outgoing queue.
 507  */
 508 static int process_response(association *assoc, request *req, Z_APDU *res)
 509 {
 510     odr_setbuf(assoc->encode, req->response, req->size_response, 1);
 511     if (!z_APDU(assoc->encode, &res, 0))
 512     {
 513         logf(LOG_WARN, "ODR error when encoding response: %s",
 514             odr_errlist[odr_geterror(assoc->decode)]);
 515         return -1;
 516     }
 517     req->response = odr_getbuf(assoc->encode, &req->len_response,
 518         &req->size_response);
 519     odr_setbuf(assoc->encode, 0, 0, 0); /* don't free if we abort later */
 520     odr_reset(assoc->encode);
 521     if (assoc->print && !z_APDU(assoc->print, &res, 0))
 522     {
 523         logf(LOG_WARN, "ODR print error: %s",
 524             odr_errlist[odr_geterror(assoc->print)]);
 525         odr_reset(assoc->print);
 526     }
 527     /* change this when we make the backend reentrant */
 528     assert(req == request_head(&assoc->incoming));
 529     req->state = REQUEST_IDLE;
 530     request_deq(&assoc->incoming);
 531     request_enq(&assoc->outgoing, req);
 532     /* turn the work over to the ir_session handler */
 533     iochan_setflag(assoc->client_chan, EVENT_OUTPUT);
 534     /* Is there more work to be done? give that to the input handler too */
 535     if (request_head(&assoc->incoming))
 536         iochan_setevent(assoc->client_chan, EVENT_WORK);
 537     return 0;
 538 }
 539
 540 /*
 541  * Handle init request.
 542  * At the moment, we don't check the protocol version or the options
 543  * anywhere else in the code - we just try not to do anything that would
 544  * break a naive client. We'll toss 'em into the association block when
 545  * we need them there.
 546  */
 547 static Z_APDU *process_initRequest(association *assoc, request *reqb)
 548 {
 549     Z_InitRequest *req = reqb->request->u.initRequest;
 550     Z_APDU *apdu = zget_APDU(assoc->encode, Z_APDU_initResponse);
 551     Z_InitResponse *resp = apdu->u.initResponse;
 552     bend_initrequest binitreq;
 553     bend_initresult *binitres;
 554
 555     logf(LOG_LOG, "Got initRequest");
 556     if (req->implementationId)
 557         logf(LOG_LOG, "Id:        %s", req->implementationId);
 558     if (req->implementationName)
 559         logf(LOG_LOG, "Name:      %s", req->implementationName);
 560     if (req->implementationVersion)
 561         logf(LOG_LOG, "Version:   %s", req->implementationVersion);
 562
 563     binitreq.configname = "default-config";
 564     binitreq.auth = req->idAuthentication;
 565     if (!(binitres = bend_init(&binitreq)))
 566     {
 567         logf(LOG_WARN, "Bad response from backend.");
 568         return 0;
 569     }
 570
 571     assoc->backend = binitres->handle;
 572     resp->referenceId = req->referenceId;
 573     /* let's tell the client what we can do */
 574     if (ODR_MASK_GET(req->options, Z_Options_search))
 575         ODR_MASK_SET(resp->options, Z_Options_search);
 576     if (ODR_MASK_GET(req->options, Z_Options_present))
 577         ODR_MASK_SET(resp->options, Z_Options_present);
 578 #if 0
 579     if (ODR_MASK_GET(req->options, Z_Options_delSet))
 580         ODR_MASK_SET(&options, Z_Options_delSet);
 581 #endif
 582     if (ODR_MASK_GET(req->options, Z_Options_namedResultSets))
 583         ODR_MASK_SET(resp->options, Z_Options_namedResultSets);
 584     if (ODR_MASK_GET(req->options, Z_Options_scan))
 585         ODR_MASK_SET(resp->options, Z_Options_scan);
 586     if (ODR_MASK_GET(req->options, Z_Options_concurrentOperations))
 587         ODR_MASK_SET(resp->options, Z_Options_concurrentOperations);
 588
 589     if (ODR_MASK_GET(req->protocolVersion, Z_ProtocolVersion_1))
 590         ODR_MASK_SET(resp->protocolVersion, Z_ProtocolVersion_1);
 591     if (ODR_MASK_GET(req->protocolVersion, Z_ProtocolVersion_2))
 592         ODR_MASK_SET(resp->protocolVersion, Z_ProtocolVersion_2);
 593     assoc->maximumRecordSize = *req->maximumRecordSize;
 594     if (assoc->maximumRecordSize > control_block->maxrecordsize)
 595         assoc->maximumRecordSize = control_block->maxrecordsize;
 596     assoc->preferredMessageSize = *req->preferredMessageSize;
 597     if (assoc->preferredMessageSize > assoc->maximumRecordSize)
 598         assoc->preferredMessageSize = assoc->maximumRecordSize;
 599     resp->preferredMessageSize = &assoc->preferredMessageSize;
 600     resp->maximumRecordSize = &assoc->maximumRecordSize;
 601     resp->implementationName = "Index Data/YAZ Generic Frontend Server";
 602     if (binitres->errcode)
 603     {
 604         logf(LOG_LOG, "Connection rejected by backend.");
 605         *resp->result = 0;
 606         assoc->rejected = 1;
 607     }
 608     return apdu;
 609 }
 610
 611 /*
 612  * These functions should be merged.
 613  */
 614
 615 /*
 616  * nonsurrogate diagnostic record.
 617  */
 618 static Z_Records *diagrec(oid_proto proto, int error, char *addinfo)
 619 {
 620     static Z_Records rec;
 621     oident bib1;
 622     static int err;
 623 #ifdef Z_95
 624     static Z_DiagRec drec;
 625     static Z_DefaultDiagFormat dr;
 626 #else
 627     static Z_DiagRec dr;
 628 #endif
 629
 630     bib1.proto = proto;
 631     bib1.class = CLASS_DIAGSET;
 632     bib1.value = VAL_BIB1;
 633
 634     logf(LOG_DEBUG, "Diagnostic: %d -- %s", error, addinfo ? addinfo :
 635         "NULL");
 636     err = error;
 637     rec.which = Z_Records_NSD;
 638 #ifdef Z_95
 639     rec.u.nonSurrogateDiagnostic = &drec;
 640     drec.which = Z_DiagRec_defaultFormat;
 641     drec.u.defaultFormat = &dr;
 642 #else
 643     rec.u.nonSurrogateDiagnostic = &dr;
 644 #endif
 645     dr.diagnosticSetId = oid_getoidbyent(&bib1);
 646     dr.condition = &err;
 647     dr.which = Z_DiagForm_v2AddInfo;
 648     dr.addinfo = addinfo ? addinfo : "";
 649     return &rec;
 650 }
 651
 652 /*
 653  * surrogate diagnostic.
 654  */
 655 static Z_NamePlusRecord *surrogatediagrec(oid_proto proto, char *dbname,
 656                                             int error, char *addinfo)
 657 {
 658     static Z_NamePlusRecord rec;
 659     static int err;
 660     oident bib1;
 661 #ifdef Z_95
 662     static Z_DiagRec drec;
 663     static Z_DefaultDiagFormat dr;
 664 #else
 665     static Z_DiagRec dr;
 666 #endif
 667
 668     bib1.proto = proto;
 669     bib1.class = CLASS_DIAGSET;
 670     bib1.value = VAL_BIB1;
 671
 672     logf(LOG_DEBUG, "SurrogateDiagnotic: %d -- %s", error, addinfo);
 673     err = error;
 674     rec.databaseName = dbname;
 675     rec.which = Z_NamePlusRecord_surrogateDiagnostic;
 676 #ifdef Z_95
 677     rec.u.surrogateDiagnostic = &drec;
 678     drec.which = Z_DiagRec_defaultFormat;
 679     drec.u.defaultFormat = &dr;
 680 #else
 681     rec.u.surrogateDiagnostic = &dr;
 682 #endif
 683     dr.diagnosticSetId = oid_getoidbyent(&bib1);
 684     dr.condition = &err;
 685     dr.which = Z_DiagForm_v2AddInfo;
 686     dr.addinfo = addinfo ? addinfo : "";
 687     return &rec;
 688 }
 689
 690 /*
 691  * multiple nonsurrogate diagnostics.
 692  */
 693 static Z_DiagRecs *diagrecs(oid_proto proto, int error, char *addinfo)
 694 {
 695     static Z_DiagRecs recs;
 696     static int err;
 697     oident bib1;
 698 #ifdef Z_95
 699     static Z_DiagRec *recp[1], drec;
 700     static Z_DefaultDiagFormat rec;
 701 #else
 702     static Z_DiagRec *recp[1], rec;
 703 #endif
 704
 705     logf(LOG_DEBUG, "DiagRecs: %d -- %s", error, addinfo);
 706     bib1.proto = proto;
 707     bib1.class = CLASS_DIAGSET;
 708     bib1.value = VAL_BIB1;
 709
 710     err = error;
 711     recs.num_diagRecs = 1;
 712     recs.diagRecs = recp;
 713 #ifdef Z_95
 714     recp[0] = &drec;
 715     drec.which = Z_DiagRec_defaultFormat;
 716     drec.u.defaultFormat = &rec;
 717 #else
 718     recp[0] = &rec;
 719 #endif
 720     rec.diagnosticSetId = oid_getoidbyent(&bib1);
 721     rec.condition = &err;
 722     rec.which = Z_DiagForm_v2AddInfo;
 723     rec.addinfo = addinfo ? addinfo : "";
 724     return &recs;
 725 }
 726
 727 #define MAX_RECORDS 256
 728
 729 static Z_Records *pack_records(association *a, char *setname, int start,
 730                                 int *num, Z_ElementSetNames *esn,
 731                                 int *next, int *pres, oid_value format)
 732 {
 733     int recno, total_length = 0, toget = *num;
 734     static Z_Records records;
 735     static Z_NamePlusRecordList reclist;
 736     static Z_NamePlusRecord *list[MAX_RECORDS];
 737     oident recform;
 738
 739     records.which = Z_Records_DBOSD;
 740     records.u.databaseOrSurDiagnostics = &reclist;
 741     reclist.num_records = 0;
 742     reclist.records = list;
 743     *pres = Z_PRES_SUCCESS;
 744     *num = 0;
 745     *next = 0;
 746
 747     logf(LOG_DEBUG, "Request to pack %d+%d", start, toget);
 748     logf(LOG_DEBUG, "pms=%d, mrs=%d", a->preferredMessageSize,
 749         a->maximumRecordSize);
 750     for (recno = start; reclist.num_records < toget; recno++)
 751     {
 752         bend_fetchrequest freq;
 753         bend_fetchresult *fres;
 754         Z_NamePlusRecord *thisrec;
 755         Z_DatabaseRecord *thisext;
 756
 757         if (reclist.num_records == MAX_RECORDS - 1)
 758         {
 759             *pres = Z_PRES_PARTIAL_2;
 760             break;
 761         }
 762         freq.setname = setname;
 763         freq.number = recno;
 764         freq.format = format;
 765         if (!(fres = bend_fetch(a->backend, &freq, 0)))
 766         {
 767             *pres = Z_PRES_FAILURE;
 768             return diagrec(a->proto, 2, "Backend interface problem");
 769         }
 770         /* backend should be able to signal whether error is system-wide
 771            or only pertaining to current record */
 772         if (fres->errcode)
 773         {
 774             *pres = Z_PRES_FAILURE;
 775             return diagrec(a->proto, fres->errcode, fres->errstring);
 776         }
 777         logf(LOG_DEBUG, "  fetched record, len=%d, total=%d",
 778             fres->len, total_length);
 779         if (fres->len + total_length > a->preferredMessageSize)
 780         {
 781             /* record is small enough, really */
 782             if (fres->len <= a->preferredMessageSize)
 783             {
 784                 logf(LOG_DEBUG, "  Dropped last normal-sized record");
 785                 *pres = Z_PRES_PARTIAL_2;
 786                 break;
 787             }
 788             /* record can only be fetched by itself */
 789             if (fres->len < a->maximumRecordSize)
 790             {
 791                 logf(LOG_DEBUG, "  Record > prefmsgsz");
 792                 if (toget > 1)
 793                 {
 794                     logf(LOG_DEBUG, "  Dropped it");
 795                     reclist.records[reclist.num_records] =
 796                          surrogatediagrec(a->proto, fres->basename, 16, 0);
 797                     reclist.num_records++;
 798                     total_length += 10; /* totally arbitrary */
 799                     continue;
 800                 }
 801             }
 802             else /* too big entirely */
 803             {
 804                 logf(LOG_DEBUG, "Record > maxrcdsz");
 805                 reclist.records[reclist.num_records] =
 806                     surrogatediagrec(a->proto, fres->basename, 17, 0);
 807                 reclist.num_records++;
 808                 total_length += 10; /* totally arbitrary */
 809                 continue;
 810             }
 811         }
 812         if (!(thisrec = odr_malloc(a->encode, sizeof(*thisrec))))
 813             return 0;
 814         if (!(thisrec->databaseName = odr_malloc(a->encode,
 815             strlen(fres->basename) + 1)))
 816             return 0;
 817         strcpy(thisrec->databaseName, fres->basename);
 818         thisrec->which = Z_NamePlusRecord_databaseRecord;
 819         if (!(thisrec->u.databaseRecord = thisext = odr_malloc(a->encode,
 820             sizeof(Z_DatabaseRecord))))
 821             return 0;
 822         recform.proto = a->proto;
 823         recform.class = CLASS_RECSYN;
 824         recform.value = fres->format;
 825         thisext->direct_reference = odr_oiddup(a->encode,
 826             oid_getoidbyent(&recform));
 827         thisext->indirect_reference = 0;
 828         thisext->descriptor = 0;
 829         if (fres->format == VAL_SUTRS) /* SUTRS is a single-ASN.1-type */
 830         {
 831             Odr_oct *sutrs = odr_malloc(a->encode, sizeof(*sutrs));
 832
 833             thisext->which = Z_External_SUTRS;
 834             thisext->u.sutrs = sutrs;
 835             sutrs->buf = odr_malloc(a->encode, fres->len);
 836             sutrs->len = sutrs->size = fres->len;
 837             memcpy(sutrs->buf, fres->record, fres->len);
 838 #if 0
 839             Odr_oct sutrs_asn;
 840             Odr_oct *sp = &sutrs_asn;
 841             Odr_any *single = odr_malloc(a->encode, sizeof(*single));
 842             char *buf, *remember;
 843             int len, s_remember;
 844
 845             sutrs_asn.buf = (unsigned char*) fres->record;
 846             sutrs_asn.len = sutrs_asn.size = fres->len;
 847             /*
 848              * we borrow the encoding stream for preparing the buffer. This
 849              * is not the most elegant solution - a better way might have been
 850              * to reserve a different stream, or to devise a better system
 851              * for handling externals in general.
 852              */
 853             remember = odr_getbuf(a->encode, &len, &s_remember);
 854             buf = odr_malloc(a->encode, fres->len + 10); /* buf for encoding */
 855             odr_setbuf(a->encode, buf, fres->len + 10, 0); /* can_grow==0 */
 856             if (!z_SUTRS(a->encode, &sp, 0))
 857             {
 858                 logf(LOG_LOG, "ODR error encoding SUTRS: %s",
 859                     odr_errlist[odr_geterror(a->encode)]);
 860                 return 0;
 861             }
 862             thisext->which = ODR_EXTERNAL_single;
 863             thisext->u.single_ASN1_type = single;
 864             single->buf = (unsigned char*)odr_getbuf(a->encode, &single->len,
 865                 &single->size);
 866             /* Now restore the encoding stream */
 867             odr_setbuf(a->encode, remember, s_remember, 1);
 868             logf(LOG_DEBUG, "   Format is SUTRS. len %d, encoded len %d",
 869                 fres->len, single->len);
 870 #endif
 871         }
 872         else /* octet-aligned record. Easy as pie */
 873         {
 874             thisext->which = Z_External_octet;
 875             if (!(thisext->u.octet_aligned = odr_malloc(a->encode,
 876                 sizeof(Odr_oct))))
 877                 return 0;
 878             if (!(thisext->u.octet_aligned->buf = odr_malloc(a->encode,
 879                 fres->len)))
 880                 return 0;
 881             memcpy(thisext->u.octet_aligned->buf, fres->record, fres->len);
 882             thisext->u.octet_aligned->len = thisext->u.octet_aligned->size =
 883                 fres->len;
 884         }
 885         reclist.records[reclist.num_records] = thisrec;
 886         reclist.num_records++;
 887         total_length += fres->len;
 888         *next = fres->last_in_set ? 0 : recno + 1;
 889     }
 890     *num = reclist.num_records;
 891     return &records;
 892 }
 893
 894 static Z_APDU *process_searchRequest(association *assoc, request *reqb,
 895     int *fd)
 896 {
 897     Z_SearchRequest *req = reqb->request->u.searchRequest;
 898     bend_searchrequest bsrq;
 899     bend_searchresult *bsrt;
 900
 901     logf(LOG_LOG, "Got SearchRequest.");
 902
 903     bsrq.setname = req->resultSetName;
 904     bsrq.replace_set = *req->replaceIndicator;
 905     bsrq.num_bases = req->num_databaseNames;
 906     bsrq.basenames = req->databaseNames;
 907     bsrq.query = req->query;
 908
 909     if (!(bsrt = bend_search(assoc->backend, &bsrq, fd)))
 910         return 0;
 911     return response_searchRequest(assoc, reqb, bsrt, fd);
 912 }
 913
 914 bend_searchresult *bend_searchresponse(void *handle) {return 0;}
 915
 916 /*
 917  * Prepare a searchresponse based on the backend results. We probably want
 918  * to look at making the fetching of records nonblocking as well, but
 919  * so far, we'll keep things simple.
 920  * If bsrt is null, that means we're called in response to a communications
 921  * event, and we'll have to get the response for ourselves.
 922  */
 923 static Z_APDU *response_searchRequest(association *assoc, request *reqb,
 924     bend_searchresult *bsrt, int *fd)
 925 {
 926     Z_SearchRequest *req = reqb->request->u.searchRequest;
 927     static Z_APDU apdu;
 928     static Z_SearchResponse resp;
 929     static int nulint = 0;
 930     static bool_t sr = 1;
 931     static int next = 0;
 932     static int none = Z_RES_NONE;
 933
 934     apdu.which = Z_APDU_searchResponse;
 935     apdu.u.searchResponse = &resp;
 936     resp.referenceId = req->referenceId;
 937 #ifdef Z_95
 938     resp.additionalSearchInfo = 0;
 939     resp.otherInfo = 0;
 940 #endif
 941     *fd = -1;
 942     if (!bsrt && !(bsrt = bend_searchresponse(assoc->backend)))
 943     {
 944         logf(LOG_FATAL, "Bad result from backend");
 945         return 0;
 946     }
 947     else if (bsrt->errcode)
 948     {
 949         resp.records = diagrec(assoc->proto, bsrt->errcode,
 950             bsrt->errstring);
 951         resp.resultCount = &nulint;
 952         resp.numberOfRecordsReturned = &nulint;
 953         resp.nextResultSetPosition = &nulint;
 954         resp.searchStatus = &nulint;
 955         resp.resultSetStatus = &none;
 956         resp.presentStatus = 0;
 957     }
 958     else
 959     {
 960         static int toget;
 961         Z_ElementSetNames *setnames;
 962         static int presst = 0;
 963
 964         resp.records = 0;
 965         resp.resultCount = &bsrt->hits;
 966
 967         /* how many records does the user agent want, then? */
 968         if (bsrt->hits <= *req->smallSetUpperBound)
 969         {
 970             toget = bsrt->hits;
 971             setnames = req->smallSetElementSetNames;
 972         }
 973         else if (bsrt->hits < *req->largeSetLowerBound)
 974         {
 975             toget = *req->mediumSetPresentNumber;
 976             if (toget > bsrt->hits)
 977                 toget = bsrt->hits;
 978             setnames = req->mediumSetElementSetNames;
 979         }
 980         else
 981             toget = 0;
 982
 983         if (toget && !resp.records)
 984         {
 985             oident *prefformat;
 986             oid_value form;
 987
 988             if (!(prefformat = oid_getentbyoid(req->preferredRecordSyntax)) ||
 989                 prefformat->class != CLASS_RECSYN)
 990                 form = VAL_NONE;
 991             else
 992                 form = prefformat->value;
 993             resp.records = pack_records(assoc, req->resultSetName, 1,
 994                 &toget, setnames, &next, &presst, form);
 995             if (!resp.records)
 996                 return 0;
 997             resp.numberOfRecordsReturned = &toget;
 998             resp.nextResultSetPosition = &next;
 999             resp.searchStatus = &sr;
1000             resp.resultSetStatus = 0;
1001             resp.presentStatus = &presst;
1002         }
1003         else
1004         {
1005             if (*resp.resultCount)
1006                 next = 1;
1007             resp.numberOfRecordsReturned = &nulint;
1008             resp.nextResultSetPosition = &next;
1009             resp.searchStatus = &sr;
1010             resp.resultSetStatus = 0;
1011             resp.presentStatus = 0;
1012         }
1013     }
1014     return &apdu;
1015 }
1016
1017 /*
1018  * Maybe we got a little over-friendly when we designed bend_fetch to
1019  * get only one record at a time. Some backends can optimise multiple-record
1020  * fetches, and at any rate, there is some overhead involved in
1021  * all that selecting and hopping around. Problem is, of course, that the
1022  * frontend can't know ahead of time how many records it'll need to
1023  * fill the negotiated PDU size. Annoying. Segmentation or not, Z/SR
1024  * is downright lousy as a bulk data transfer protocol.
1025  *
1026  * To start with, we'll do the fetching of records from the backend
1027  * in one operation: To save some trips in and out of the event-handler,
1028  * and to simplify the interface to pack_records. At any rate, asynch
1029  * operation is more fun in operations that have an unpredictable execution
1030  * speed - which is normally more true for search than for present.
1031  */
1032 static Z_APDU *process_presentRequest(association *assoc, request *reqb,
1033     int *fd)
1034 {
1035     Z_PresentRequest *req = reqb->request->u.presentRequest;
1036     static Z_APDU apdu;
1037     static Z_PresentResponse resp;
1038     static int presst, next, num;
1039     oident *prefformat;
1040     oid_value form;
1041
1042
1043     logf(LOG_LOG, "Got PresentRequest.");
1044     apdu.which = Z_APDU_presentResponse;
1045     apdu.u.presentResponse = &resp;
1046     resp.referenceId = req->referenceId;
1047 #ifdef Z_95
1048     resp.otherInfo = 0;
1049 #endif
1050
1051     if (!(prefformat = oid_getentbyoid(req->preferredRecordSyntax)) ||
1052         prefformat->class != CLASS_RECSYN)
1053         form = VAL_NONE;
1054     else
1055         form = prefformat->value;
1056     num = *req->numberOfRecordsRequested;
1057     resp.records = pack_records(assoc, req->resultSetId,
1058         *req->resultSetStartPoint, &num, 0, &next, &presst, form);
1059     if (!resp.records)
1060         return 0;
1061     resp.numberOfRecordsReturned = &num;
1062     resp.presentStatus = &presst;
1063     resp.nextResultSetPosition = &next;
1064
1065     return &apdu;
1066 }
1067
1068 /*
1069  * Scan was implemented rather in a hurry, and with support for only the basic
1070  * elements of the service in the backend API. Suggestions are welcome.
1071  */
1072 static Z_APDU *process_scanRequest(association *assoc, request *reqb, int *fd)
1073 {
1074     Z_ScanRequest *req = reqb->request->u.scanRequest;
1075     static Z_APDU apdu;
1076     static Z_ScanResponse res;
1077     static int scanStatus = Z_Scan_failure;
1078     static int numberOfEntriesReturned = 0;
1079     oident *attent;
1080     static Z_ListEntries ents;
1081 #define SCAN_MAX_ENTRIES 200
1082     static Z_Entry *tab[SCAN_MAX_ENTRIES];
1083     bend_scanrequest srq;
1084     bend_scanresult *srs;
1085
1086     logf(LOG_LOG, "Got scanrequest");
1087     apdu.which = Z_APDU_scanResponse;
1088     apdu.u.scanResponse = &res;
1089     res.referenceId = req->referenceId;
1090     res.stepSize = 0;
1091     res.scanStatus = &scanStatus;
1092     res.numberOfEntriesReturned = &numberOfEntriesReturned;
1093     res.positionOfTerm = 0;
1094     res.entries = &ents;
1095     ents.which = Z_ListEntries_nonSurrogateDiagnostics;
1096     res.attributeSet = 0;
1097 #ifdef Z_95
1098     res.otherInfo = 0;
1099 #endif
1100
1101     if (req->attributeSet && (!(attent = oid_getentbyoid(req->attributeSet)) ||
1102         attent->class != CLASS_ATTSET || attent->value != VAL_BIB1))
1103         ents.u.nonSurrogateDiagnostics = diagrecs(assoc->proto, 121, 0);
1104     else if (req->stepSize && *req->stepSize > 0)
1105         ents.u.nonSurrogateDiagnostics = diagrecs(assoc->proto, 205, 0);
1106     else
1107     {
1108         if (req->termListAndStartPoint->term->which == Z_Term_general)
1109             logf(LOG_DEBUG, " term: '%.*s'",
1110                 req->termListAndStartPoint->term->u.general->len,
1111                 req->termListAndStartPoint->term->u.general->buf);
1112         srq.num_bases = req->num_databaseNames;
1113         srq.basenames = req->databaseNames;
1114         srq.num_entries = *req->numberOfTermsRequested;
1115         srq.term = req->termListAndStartPoint;
1116         srq.term_position = req->preferredPositionInResponse ?
1117             *req->preferredPositionInResponse : 1;
1118         if (!(srs = bend_scan(assoc->backend, &srq, 0)))
1119             ents.u.nonSurrogateDiagnostics = diagrecs(assoc->proto, 2, 0);
1120         else if (srs->errcode)
1121             ents.u.nonSurrogateDiagnostics = diagrecs(assoc->proto,
1122                 srs->errcode, srs->errstring);
1123         else
1124         {
1125             int i;
1126             static Z_Entries list;
1127
1128             if (srs->status == BEND_SCAN_PARTIAL)
1129                 scanStatus = Z_Scan_partial_5;
1130             else
1131                 scanStatus = Z_Scan_success;
1132             ents.which = Z_ListEntries_entries;
1133             ents.u.entries = &list;
1134             list.entries = tab;
1135             for (i = 0; i < srs->num_entries; i++)
1136             {
1137                 Z_Entry *e;
1138                 Z_TermInfo *t;
1139                 Odr_oct *o;
1140
1141                 if (i >= SCAN_MAX_ENTRIES)
1142                 {
1143                     scanStatus = Z_Scan_partial_4;
1144                     break;
1145                 }
1146                 list.entries[i] = e = odr_malloc(assoc->encode, sizeof(*e));
1147                 e->which = Z_Entry_termInfo;
1148                 e->u.termInfo = t = odr_malloc(assoc->encode, sizeof(*t));
1149                 t->suggestedAttributes = 0;
1150                 t->alternativeTerm = 0;
1151                 t->byAttributes = 0;
1152                 t->globalOccurrences = &srs->entries[i].occurrences;
1153                 t->term = odr_malloc(assoc->encode, sizeof(*t->term));
1154                 t->term->which = Z_Term_general;
1155                 t->term->u.general = o = odr_malloc(assoc->encode,
1156                     sizeof(Odr_oct));
1157                 o->buf = odr_malloc(assoc->encode, o->len = o->size =
1158                     strlen(srs->entries[i].term));
1159                 memcpy(o->buf, srs->entries[i].term, o->len);
1160                 logf(LOG_DEBUG, "  term #%d: '%s' (%d)", i,
1161                     srs->entries[i].term, srs->entries[i].occurrences);
1162             }
1163             list.num_entries = i;
1164             res.numberOfEntriesReturned = &list.num_entries;
1165             res.positionOfTerm = &srs->term_position;
1166         }
1167     }
1168
1169     return &apdu;
1170 }