src/filter_multi.cpp

   1 /* $Id: filter_multi.cpp,v 1.6 2006-01-17 18:55:55 adam Exp $
   2    Copyright (c) 2005, Index Data.
   3
   4 %LICENSE%
   5  */
   6
   7 #include "config.hpp"
   8
   9 #include "filter.hpp"
  10 #include "package.hpp"
  11
  12 #include <boost/thread/thread.hpp>
  13 #include <boost/thread/mutex.hpp>
  14 #include <boost/thread/condition.hpp>
  15 #include <boost/shared_ptr.hpp>
  16
  17 #include "util.hpp"
  18 #include "filter_multi.hpp"
  19
  20 #include <yaz/zgdu.h>
  21 #include <yaz/otherinfo.h>
  22 #include <yaz/diagbib1.h>
  23
  24 #include <map>
  25 #include <iostream>
  26
  27 namespace yf = yp2::filter;
  28
  29 namespace yp2 {
  30     namespace filter {
  31
  32         struct Multi::BackendSet {
  33             BackendPtr m_backend;
  34             int m_count;
  35             bool operator < (const BackendSet &k) const;
  36         };
  37         struct Multi::FrontendSet {
  38             struct PresentJob {
  39                 BackendPtr m_backend;
  40                 int m_pos;
  41                 int m_inside_pos;
  42             };
  43             FrontendSet(std::string setname);
  44             FrontendSet();
  45             ~FrontendSet();
  46
  47             void round_robin(int pos, int number, std::list<PresentJob> &job);
  48
  49             std::list<BackendSet> m_backend_sets;
  50             std::string m_setname;
  51         };
  52         struct Multi::Backend {
  53             PackagePtr m_package;
  54             std::string m_backend_database;
  55             std::string m_vhost;
  56             std::string m_route;
  57             void operator() (void);  // thread operation
  58         };
  59         struct Multi::Frontend {
  60             Frontend(Rep *rep);
  61             ~Frontend();
  62             bool m_is_multi;
  63             bool m_in_use;
  64             std::list<BackendPtr> m_backend_list;
  65             std::map<std::string,Multi::FrontendSet> m_sets;
  66
  67             void multi_move(std::list<BackendPtr> &blist);
  68             void init(Package &package, Z_GDU *gdu);
  69             void close(Package &package);
  70             void search(Package &package, Z_APDU *apdu);
  71             void present(Package &package, Z_APDU *apdu);
  72             void scan(Package &package, Z_APDU *apdu);
  73             Rep *m_p;
  74         };
  75         struct Multi::Map {
  76             Map(std::list<std::string> hosts, std::string route);
  77             Map();
  78             std::list<std::string> m_hosts;
  79             std::string m_route;
  80         };
  81         class Multi::Rep {
  82             friend class Multi;
  83             friend class Frontend;
  84
  85             FrontendPtr get_frontend(Package &package);
  86             void release_frontend(Package &package);
  87         private:
  88             boost::mutex m_sessions_mutex;
  89             std::map<std::string, Multi::Map>m_maps;
  90
  91             boost::mutex m_mutex;
  92             boost::condition m_cond_session_ready;
  93             std::map<yp2::Session, FrontendPtr> m_clients;
  94         };
  95     }
  96 }
  97
  98 using namespace yp2;
  99
 100 bool yf::Multi::BackendSet::operator < (const BackendSet &k) const
 101 {
 102     return m_count < k.m_count;
 103 }
 104
 105 yf::Multi::Frontend::Frontend(Rep *rep)
 106 {
 107     m_p = rep;
 108     m_is_multi = false;
 109 }
 110
 111 yf::Multi::Frontend::~Frontend()
 112 {
 113 }
 114
 115 yf::Multi::FrontendPtr yf::Multi::Rep::get_frontend(Package &package)
 116 {
 117     boost::mutex::scoped_lock lock(m_mutex);
 118
 119     std::map<yp2::Session,yf::Multi::FrontendPtr>::iterator it;
 120
 121     while(true)
 122     {
 123         it = m_clients.find(package.session());
 124         if (it == m_clients.end())
 125             break;
 126
 127         if (!it->second->m_in_use)
 128         {
 129             it->second->m_in_use = true;
 130             return it->second;
 131         }
 132         m_cond_session_ready.wait(lock);
 133     }
 134     FrontendPtr f(new Frontend(this));
 135     m_clients[package.session()] = f;
 136     f->m_in_use = true;
 137     return f;
 138 }
 139
 140 void yf::Multi::Rep::release_frontend(Package &package)
 141 {
 142     boost::mutex::scoped_lock lock(m_mutex);
 143     std::map<yp2::Session,yf::Multi::FrontendPtr>::iterator it;
 144
 145     it = m_clients.find(package.session());
 146     if (it != m_clients.end())
 147     {
 148         if (package.session().is_closed())
 149         {
 150             it->second->close(package);
 151             m_clients.erase(it);
 152         }
 153         else
 154         {
 155             it->second->m_in_use = false;
 156         }
 157         m_cond_session_ready.notify_all();
 158     }
 159 }
 160
 161 yf::Multi::FrontendSet::FrontendSet(std::string setname)
 162     :  m_setname(setname)
 163 {
 164 }
 165
 166
 167 yf::Multi::FrontendSet::FrontendSet()
 168 {
 169 }
 170
 171
 172 yf::Multi::FrontendSet::~FrontendSet()
 173 {
 174 }
 175
 176 yf::Multi::Map::Map(std::list<std::string> hosts, std::string route)
 177     : m_hosts(hosts), m_route(route)
 178 {
 179 }
 180
 181 yf::Multi::Map::Map()
 182 {
 183 }
 184
 185 yf::Multi::Multi() : m_p(new Multi::Rep)
 186 {
 187 }
 188
 189 yf::Multi::~Multi() {
 190 }
 191
 192
 193 void yf::Multi::add_map_host2hosts(std::string host,
 194                                    std::list<std::string> hosts,
 195                                    std::string route)
 196 {
 197     m_p->m_maps[host] = Multi::Map(hosts, route);
 198 }
 199
 200 void yf::Multi::Backend::operator() (void)
 201 {
 202     m_package->move(m_route);
 203 }
 204
 205 void yf::Multi::Frontend::close(Package &package)
 206 {
 207     std::list<BackendPtr>::const_iterator bit;
 208     for (bit = m_backend_list.begin(); bit != m_backend_list.end(); bit++)
 209     {
 210         BackendPtr b = *bit;
 211
 212         b->m_package->copy_filter(package);
 213         b->m_package->request() = (Z_GDU *) 0;
 214         b->m_package->session().close();
 215         b->m_package->move(b->m_route);
 216     }
 217 }
 218
 219 void yf::Multi::Frontend::multi_move(std::list<BackendPtr> &blist)
 220 {
 221     std::list<BackendPtr>::const_iterator bit;
 222     boost::thread_group g;
 223     for (bit = blist.begin(); bit != blist.end(); bit++)
 224     {
 225         g.add_thread(new boost::thread(**bit));
 226     }
 227     g.join_all();
 228 }
 229
 230
 231 void yf::Multi::FrontendSet::round_robin(int start, int number,
 232                                          std::list<PresentJob> &jobs)
 233 {
 234     int fetched = 0;
 235     int p = 1;
 236     bool eof = true;
 237
 238     std::list<int> pos;
 239     std::list<int> inside_pos;
 240     std::list<BackendSet>::const_iterator bsit;
 241     for (bsit = m_backend_sets.begin(); bsit != m_backend_sets.end(); bsit++)
 242     {
 243         pos.push_back(1);
 244         inside_pos.push_back(0);
 245     }
 246
 247     std::list<int>::iterator psit = pos.begin();
 248     std::list<int>::iterator esit = inside_pos.begin();
 249     bsit = m_backend_sets.begin();
 250     while (fetched < number)
 251     {
 252         if (bsit == m_backend_sets.end())
 253         {
 254             psit = pos.begin();
 255             esit = inside_pos.begin();
 256             bsit = m_backend_sets.begin();
 257             if (eof)
 258                 break;
 259             eof = true;
 260         }
 261         if (*psit <= bsit->m_count)
 262         {
 263             if (p >= start)
 264             {
 265                 PresentJob job;
 266                 job.m_backend = bsit->m_backend;
 267                 job.m_pos = *psit;
 268                 job.m_inside_pos = *esit;
 269                 jobs.push_back(job);
 270                 (*esit)++;
 271                 fetched++;
 272             }
 273             (*psit)++;
 274             p++;
 275             eof = false;
 276         }
 277         psit++;
 278         esit++;
 279         bsit++;
 280     }
 281 }
 282
 283 void yf::Multi::Frontend::init(Package &package, Z_GDU *gdu)
 284 {
 285     Z_InitRequest *req = gdu->u.z3950->u.initRequest;
 286
 287     std::list<std::string> targets;
 288
 289     yp2::util::get_vhost_otherinfo(&req->otherInfo, false, targets);
 290
 291     if (targets.size() < 1)
 292     {
 293         package.move();
 294         return;
 295     }
 296
 297     std::list<std::string>::const_iterator t_it = targets.begin();
 298     for (; t_it != targets.end(); t_it++)
 299     {
 300         Session s;
 301         Backend *b = new Backend;
 302         b->m_vhost = *t_it;
 303
 304         // b->m_route unset
 305         b->m_package = PackagePtr(new Package(s, package.origin()));
 306
 307         m_backend_list.push_back(BackendPtr(b));
 308     }
 309     m_is_multi = true;
 310
 311     // create init request
 312     std::list<BackendPtr>::const_iterator bit;
 313     for (bit = m_backend_list.begin(); bit != m_backend_list.end(); bit++)
 314     {
 315         yp2::odr odr;
 316         BackendPtr b = *bit;
 317         Z_APDU *init_apdu = zget_APDU(odr, Z_APDU_initRequest);
 318
 319         yaz_oi_set_string_oidval(&init_apdu->u.initRequest->otherInfo, odr,
 320                                  VAL_PROXY, 1, b->m_vhost.c_str());
 321
 322         Z_InitRequest *req = init_apdu->u.initRequest;
 323
 324         ODR_MASK_SET(req->options, Z_Options_search);
 325         ODR_MASK_SET(req->options, Z_Options_present);
 326         ODR_MASK_SET(req->options, Z_Options_namedResultSets);
 327         ODR_MASK_SET(req->options, Z_Options_scan);
 328
 329         ODR_MASK_SET(req->protocolVersion, Z_ProtocolVersion_1);
 330         ODR_MASK_SET(req->protocolVersion, Z_ProtocolVersion_2);
 331         ODR_MASK_SET(req->protocolVersion, Z_ProtocolVersion_3);
 332
 333         b->m_package->request() = init_apdu;
 334
 335         b->m_package->copy_filter(package);
 336     }
 337     multi_move(m_backend_list);
 338
 339     // create the frontend init response based on each backend init response
 340     yp2::odr odr;
 341
 342     Z_APDU *f_apdu = odr.create_initResponse(gdu->u.z3950, 0, 0);
 343     Z_InitResponse *f_resp = f_apdu->u.initResponse;
 344
 345     ODR_MASK_SET(f_resp->options, Z_Options_search);
 346     ODR_MASK_SET(f_resp->options, Z_Options_present);
 347     ODR_MASK_SET(f_resp->options, Z_Options_namedResultSets);
 348
 349     ODR_MASK_SET(f_resp->protocolVersion, Z_ProtocolVersion_1);
 350     ODR_MASK_SET(f_resp->protocolVersion, Z_ProtocolVersion_2);
 351     ODR_MASK_SET(f_resp->protocolVersion, Z_ProtocolVersion_3);
 352
 353     for (bit = m_backend_list.begin(); bit != m_backend_list.end(); bit++)
 354     {
 355         PackagePtr p = (*bit)->m_package;
 356
 357         if (p->session().is_closed()) // if any backend closes, close frontend
 358             package.session().close();
 359         Z_GDU *gdu = p->response().get();
 360         if (gdu && gdu->which == Z_GDU_Z3950 && gdu->u.z3950->which ==
 361             Z_APDU_initResponse)
 362         {
 363             int i;
 364             Z_APDU *b_apdu = gdu->u.z3950;
 365             Z_InitResponse *b_resp = b_apdu->u.initResponse;
 366
 367             // common options for all backends
 368             for (i = 0; i <= Z_Options_stringSchema; i++)
 369             {
 370                 if (!ODR_MASK_GET(b_resp->options, i))
 371                     ODR_MASK_CLEAR(f_resp->options, i);
 372             }
 373             // common protocol version
 374             for (i = 0; i <= Z_ProtocolVersion_3; i++)
 375                 if (!ODR_MASK_GET(b_resp->protocolVersion, i))
 376                     ODR_MASK_CLEAR(f_resp->protocolVersion, i);
 377             // reject if any of the backends reject
 378             if (!*b_resp->result)
 379                 *f_resp->result = 0;
 380         }
 381         else
 382         {
 383             // if any target does not return init return that (close or
 384             // similar )
 385             package.response() = p->response();
 386             return;
 387         }
 388     }
 389     package.response() = f_apdu;
 390 }
 391
 392 void yf::Multi::Frontend::search(Package &package, Z_APDU *apdu_req)
 393 {
 394     // create search request
 395     Z_SearchRequest *req = apdu_req->u.searchRequest;
 396
 397     // save these for later
 398     int smallSetUpperBound = *req->smallSetUpperBound;
 399     int largeSetLowerBound = *req->largeSetLowerBound;
 400     int mediumSetPresentNumber = *req->mediumSetPresentNumber;
 401
 402     // they are altered now - to disable piggyback
 403     *req->smallSetUpperBound = 0;
 404     *req->largeSetLowerBound = 1;
 405     *req->mediumSetPresentNumber = 1;
 406
 407     int default_num_db = req->num_databaseNames;
 408     char **default_db = req->databaseNames;
 409
 410     std::list<BackendPtr>::const_iterator bit;
 411     for (bit = m_backend_list.begin(); bit != m_backend_list.end(); bit++)
 412     {
 413         PackagePtr p = (*bit)->m_package;
 414         yp2::odr odr;
 415
 416         if (!yp2::util::set_databases_from_zurl(odr, (*bit)->m_vhost,
 417                                                 &req->num_databaseNames,
 418                                                 &req->databaseNames))
 419         {
 420             req->num_databaseNames = default_num_db;
 421             req->databaseNames = default_db;
 422         }
 423         p->request() = apdu_req;
 424         p->copy_filter(package);
 425     }
 426     multi_move(m_backend_list);
 427
 428     // look at each response
 429     FrontendSet resultSet(std::string(req->resultSetName));
 430
 431     int result_set_size = 0;
 432     Z_Records *z_records_diag = 0;  // no diagnostics (yet)
 433     for (bit = m_backend_list.begin(); bit != m_backend_list.end(); bit++)
 434     {
 435         PackagePtr p = (*bit)->m_package;
 436
 437         if (p->session().is_closed()) // if any backend closes, close frontend
 438             package.session().close();
 439
 440         Z_GDU *gdu = p->response().get();
 441         if (gdu && gdu->which == Z_GDU_Z3950 && gdu->u.z3950->which ==
 442             Z_APDU_searchResponse)
 443         {
 444             Z_APDU *b_apdu = gdu->u.z3950;
 445             Z_SearchResponse *b_resp = b_apdu->u.searchResponse;
 446
 447             // see we get any errors (AKA diagnstics)
 448             if (b_resp->records)
 449             {
 450                 if (b_resp->records->which == Z_Records_NSD
 451                     || b_resp->records->which == Z_Records_multipleNSD)
 452                     z_records_diag = b_resp->records;
 453                 // we may set this multiple times (TOO BAD!)
 454             }
 455             BackendSet backendSet;
 456             backendSet.m_backend = *bit;
 457             backendSet.m_count = *b_resp->resultCount;
 458             result_set_size += *b_resp->resultCount;
 459             resultSet.m_backend_sets.push_back(backendSet);
 460         }
 461         else
 462         {
 463             // if any target does not return search response - return that
 464             package.response() = p->response();
 465             return;
 466         }
 467     }
 468
 469     yp2::odr odr;
 470     Z_APDU *f_apdu = odr.create_searchResponse(apdu_req, 0, 0);
 471     Z_SearchResponse *f_resp = f_apdu->u.searchResponse;
 472
 473     *f_resp->resultCount = result_set_size;
 474     if (z_records_diag)
 475     {
 476         // search error
 477         f_resp->records = z_records_diag;
 478         package.response() = f_apdu;
 479         return;
 480     }
 481     // assume OK
 482     m_sets[resultSet.m_setname] = resultSet;
 483
 484     int number;
 485     yp2::util::piggyback(smallSetUpperBound,
 486                          largeSetLowerBound,
 487                          mediumSetPresentNumber,
 488                          result_set_size,
 489                          number);
 490     Package pp(package.session(), package.origin());
 491     if (number > 0)
 492     {
 493         pp.copy_filter(package);
 494         Z_APDU *p_apdu = zget_APDU(odr, Z_APDU_presentRequest);
 495         Z_PresentRequest *p_req = p_apdu->u.presentRequest;
 496         p_req->preferredRecordSyntax = req->preferredRecordSyntax;
 497         p_req->resultSetId = req->resultSetName;
 498         *p_req->resultSetStartPoint = 1;
 499         *p_req->numberOfRecordsRequested = number;
 500         pp.request() = p_apdu;
 501         present(pp, p_apdu);
 502
 503         if (pp.session().is_closed())
 504             package.session().close();
 505
 506         Z_GDU *gdu = pp.response().get();
 507         if (gdu && gdu->which == Z_GDU_Z3950 && gdu->u.z3950->which ==
 508             Z_APDU_presentResponse)
 509         {
 510             Z_PresentResponse *p_res = gdu->u.z3950->u.presentResponse;
 511             f_resp->records = p_res->records;
 512             *f_resp->numberOfRecordsReturned =
 513                 *p_res->numberOfRecordsReturned;
 514             *f_resp->nextResultSetPosition =
 515                 *p_res->nextResultSetPosition;
 516         }
 517         else
 518         {
 519             package.response() = pp.response();
 520             return;
 521         }
 522     }
 523     package.response() = f_apdu; // in this scope because of p
 524 }
 525
 526 void yf::Multi::Frontend::present(Package &package, Z_APDU *apdu_req)
 527 {
 528     // create present request
 529     Z_PresentRequest *req = apdu_req->u.presentRequest;
 530
 531     Sets_it it;
 532     it = m_sets.find(std::string(req->resultSetId));
 533     if (it == m_sets.end())
 534     {
 535         yp2::odr odr;
 536         Z_APDU *apdu =
 537             odr.create_presentResponse(
 538                 apdu_req,
 539                 YAZ_BIB1_SPECIFIED_RESULT_SET_DOES_NOT_EXIST,
 540                 req->resultSetId);
 541         package.response() = apdu;
 542         return;
 543     }
 544     std::list<Multi::FrontendSet::PresentJob> jobs;
 545     int start = *req->resultSetStartPoint;
 546     int number = *req->numberOfRecordsRequested;
 547     it->second.round_robin(start, number, jobs);
 548
 549     std::list<BackendPtr> present_backend_list;
 550
 551     std::list<BackendSet>::const_iterator bsit;
 552     bsit = it->second.m_backend_sets.begin();
 553     for (; bsit != it->second.m_backend_sets.end(); bsit++)
 554     {
 555         std::list<Multi::FrontendSet::PresentJob>::const_iterator jit;
 556         int start = -1;
 557         int end = -1;
 558
 559         for (jit = jobs.begin(); jit != jobs.end(); jit++)
 560         {
 561             if (jit->m_backend == bsit->m_backend)
 562             {
 563                 if (start == -1 || jit->m_pos < start)
 564                     start = jit->m_pos;
 565                 if (end == -1 || jit->m_pos > end)
 566                     end = jit->m_pos;
 567             }
 568         }
 569         if (start != -1)
 570         {
 571             PackagePtr p = bsit->m_backend->m_package;
 572
 573             *req->resultSetStartPoint = start;
 574             *req->numberOfRecordsRequested = end - start + 1;
 575
 576             p->request() = apdu_req;
 577             p->copy_filter(package);
 578
 579             present_backend_list.push_back(bsit->m_backend);
 580         }
 581     }
 582     multi_move(present_backend_list);
 583
 584     // look at each response
 585     Z_Records *z_records_diag = 0;
 586
 587     std::list<BackendPtr>::const_iterator pbit = present_backend_list.begin();
 588     for (; pbit != present_backend_list.end(); pbit++)
 589     {
 590         PackagePtr p = (*pbit)->m_package;
 591
 592         if (p->session().is_closed()) // if any backend closes, close frontend
 593             package.session().close();
 594
 595         Z_GDU *gdu = p->response().get();
 596         if (gdu && gdu->which == Z_GDU_Z3950 && gdu->u.z3950->which ==
 597             Z_APDU_presentResponse)
 598         {
 599             Z_APDU *b_apdu = gdu->u.z3950;
 600             Z_PresentResponse *b_resp = b_apdu->u.presentResponse;
 601
 602             // see we get any errors (AKA diagnstics)
 603             if (b_resp->records)
 604             {
 605                 if (b_resp->records->which != Z_Records_DBOSD)
 606                     z_records_diag = b_resp->records;
 607                 // we may set this multiple times (TOO BAD!)
 608             }
 609         }
 610         else
 611         {
 612             // if any target does not return present response - return that
 613             package.response() = p->response();
 614             return;
 615         }
 616     }
 617
 618     yp2::odr odr;
 619     Z_APDU *f_apdu = odr.create_presentResponse(apdu_req, 0, 0);
 620     Z_PresentResponse *f_resp = f_apdu->u.presentResponse;
 621
 622     if (z_records_diag)
 623     {
 624         f_resp->records = z_records_diag;
 625         *f_resp->presentStatus = Z_PresentStatus_failure;
 626     }
 627     else
 628     {
 629         f_resp->records = (Z_Records *) odr_malloc(odr, sizeof(Z_Records));
 630         Z_Records * records = f_resp->records;
 631         records->which = Z_Records_DBOSD;
 632         records->u.databaseOrSurDiagnostics =
 633             (Z_NamePlusRecordList *)
 634             odr_malloc(odr, sizeof(Z_NamePlusRecordList));
 635         Z_NamePlusRecordList *nprl = records->u.databaseOrSurDiagnostics;
 636         nprl->num_records = jobs.size();
 637         nprl->records = (Z_NamePlusRecord**)
 638             odr_malloc(odr, sizeof(Z_NamePlusRecord *) * nprl->num_records);
 639         int i = 0;
 640         std::list<Multi::FrontendSet::PresentJob>::const_iterator jit;
 641         for (jit = jobs.begin(); jit != jobs.end(); jit++)
 642         {
 643             PackagePtr p = jit->m_backend->m_package;
 644
 645             Z_GDU *gdu = p->response().get();
 646             Z_APDU *b_apdu = gdu->u.z3950;
 647             Z_PresentResponse *b_resp = b_apdu->u.presentResponse;
 648
 649             nprl->records[i++] =
 650                 b_resp->records->u.databaseOrSurDiagnostics->
 651                 records[jit->m_inside_pos];
 652         }
 653         *f_resp->nextResultSetPosition = start + i;
 654         *f_resp->numberOfRecordsReturned = i;
 655     }
 656     package.response() = f_apdu;
 657 }
 658
 659 void yf::Multi::Frontend::scan(Package &package, Z_APDU *apdu_req)
 660 {
 661     if (m_backend_list.size() > 1)
 662     {
 663         yp2::odr odr;
 664         Z_APDU *f_apdu =
 665             odr.create_scanResponse(
 666                 apdu_req, YAZ_BIB1_COMBI_OF_SPECIFIED_DATABASES_UNSUPP, 0);
 667         package.response() = f_apdu;
 668         return;
 669     }
 670     Z_ScanRequest *req = apdu_req->u.scanRequest;
 671
 672     int default_num_db = req->num_databaseNames;
 673     char **default_db = req->databaseNames;
 674
 675     std::list<BackendPtr>::const_iterator bit;
 676     for (bit = m_backend_list.begin(); bit != m_backend_list.end(); bit++)
 677     {
 678         PackagePtr p = (*bit)->m_package;
 679         yp2::odr odr;
 680
 681         if (!yp2::util::set_databases_from_zurl(odr, (*bit)->m_vhost,
 682                                                 &req->num_databaseNames,
 683                                                 &req->databaseNames))
 684         {
 685             req->num_databaseNames = default_num_db;
 686             req->databaseNames = default_db;
 687         }
 688         p->request() = apdu_req;
 689         p->copy_filter(package);
 690     }
 691     multi_move(m_backend_list);
 692
 693     for (bit = m_backend_list.begin(); bit != m_backend_list.end(); bit++)
 694     {
 695         PackagePtr p = (*bit)->m_package;
 696
 697         if (p->session().is_closed()) // if any backend closes, close frontend
 698             package.session().close();
 699
 700         Z_GDU *gdu = p->response().get();
 701         if (gdu && gdu->which == Z_GDU_Z3950 && gdu->u.z3950->which ==
 702             Z_APDU_scanResponse)
 703         {
 704             package.response() = p->response();
 705             break;
 706         }
 707         else
 708         {
 709             // if any target does not return scan response - return that
 710             package.response() = p->response();
 711             return;
 712         }
 713     }
 714 }
 715
 716 void yf::Multi::process(Package &package) const
 717 {
 718     FrontendPtr f = m_p->get_frontend(package);
 719
 720     Z_GDU *gdu = package.request().get();
 721
 722     if (gdu && gdu->which == Z_GDU_Z3950 && gdu->u.z3950->which ==
 723         Z_APDU_initRequest && !f->m_is_multi)
 724     {
 725         f->init(package, gdu);
 726     }
 727     else if (!f->m_is_multi)
 728         package.move();
 729     else if (gdu && gdu->which == Z_GDU_Z3950)
 730     {
 731         Z_APDU *apdu = gdu->u.z3950;
 732         if (apdu->which == Z_APDU_initRequest)
 733         {
 734             yp2::odr odr;
 735
 736             package.response() = odr.create_close(
 737                 apdu,
 738                 Z_Close_protocolError,
 739                 "double init");
 740
 741             package.session().close();
 742         }
 743         else if (apdu->which == Z_APDU_searchRequest)
 744         {
 745             f->search(package, apdu);
 746         }
 747         else if (apdu->which == Z_APDU_presentRequest)
 748         {
 749             f->present(package, apdu);
 750         }
 751         else if (apdu->which == Z_APDU_scanRequest)
 752         {
 753             f->scan(package, apdu);
 754         }
 755         else
 756         {
 757             yp2::odr odr;
 758
 759             package.response() = odr.create_close(
 760                 apdu, Z_Close_protocolError,
 761                 "unsupported APDU in filter multi");
 762
 763             package.session().close();
 764         }
 765     }
 766     m_p->release_frontend(package);
 767 }
 768
 769 void yp2::filter::Multi::configure(const xmlNode * ptr)
 770 {
 771     for (ptr = ptr->children; ptr; ptr = ptr->next)
 772     {
 773         if (ptr->type != XML_ELEMENT_NODE)
 774             continue;
 775         if (!strcmp((const char *) ptr->name, "virtual"))
 776         {
 777             std::list<std::string> targets;
 778             std::string vhost;
 779             xmlNode *v_node = ptr->children;
 780             for (; v_node; v_node = v_node->next)
 781             {
 782                 if (v_node->type != XML_ELEMENT_NODE)
 783                     continue;
 784
 785                 if (yp2::xml::is_element_yp2(v_node, "vhost"))
 786                     vhost = yp2::xml::get_text(v_node);
 787                 else if (yp2::xml::is_element_yp2(v_node, "target"))
 788                     targets.push_back(yp2::xml::get_text(v_node));
 789                 else
 790                     throw yp2::filter::FilterException
 791                         ("Bad element "
 792                          + std::string((const char *) v_node->name)
 793                          + " in virtual section"
 794                             );
 795             }
 796             std::string route = yp2::xml::get_route(ptr);
 797             add_map_host2hosts(vhost, targets, route);
 798             std::list<std::string>::const_iterator it;
 799             for (it = targets.begin(); it != targets.end(); it++)
 800             {
 801                 std::cout << "Add " << vhost << "->" << *it
 802                           << "," << route << "\n";
 803             }
 804         }
 805         else
 806         {
 807             throw yp2::filter::FilterException
 808                 ("Bad element "
 809                  + std::string((const char *) ptr->name)
 810                  + " in virt_db filter");
 811         }
 812     }
 813 }
 814
 815 static yp2::filter::Base* filter_creator()
 816 {
 817     return new yp2::filter::Multi;
 818 }
 819
 820 extern "C" {
 821     struct yp2_filter_struct yp2_filter_multi = {
 822         0,
 823         "multi",
 824         filter_creator
 825     };
 826 }
 827
 828
 829 /*
 830  * Local variables:
 831  * c-basic-offset: 4
 832  * indent-tabs-mode: nil
 833  * c-file-style: "stroustrup"
 834  * End:
 835  * vim: shiftwidth=4 tabstop=8 expandtab
 836  */