src/filter_virt_db.cpp

   1 /* This file is part of Metaproxy.
   2    Copyright (C) 2005-2010 Index Data
   3
   4 Metaproxy is free software; you can redistribute it and/or modify it under
   5 the terms of the GNU General Public License as published by the Free
   6 Software Foundation; either version 2, or (at your option) any later
   7 version.
   8
   9 Metaproxy is distributed in the hope that it will be useful, but WITHOUT ANY
  10 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12 for more details.
  13
  14 You should have received a copy of the GNU General Public License
  15 along with this program; if not, write to the Free Software
  16 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  17 */
  18
  19 #include "config.hpp"
  20
  21 #include "filter_virt_db.hpp"
  22 #include <metaproxy/package.hpp>
  23
  24 #include <boost/thread/mutex.hpp>
  25 #include <boost/thread/condition.hpp>
  26 #include <boost/shared_ptr.hpp>
  27
  28 #include <metaproxy/util.hpp>
  29
  30 #include <yaz/zgdu.h>
  31 #include <yaz/otherinfo.h>
  32 #include <yaz/diagbib1.h>
  33 #include <yaz/match_glob.h>
  34
  35 #include <map>
  36 #include <iostream>
  37
  38 namespace mp = metaproxy_1;
  39 namespace yf = mp::filter;
  40
  41 namespace metaproxy_1 {
  42     namespace filter {
  43
  44         struct VirtualDB::Set {
  45             Set(BackendPtr b, std::string setname);
  46             Set();
  47             ~Set();
  48
  49             BackendPtr m_backend;
  50             std::string m_setname;
  51         };
  52         struct VirtualDB::Map {
  53             Map(std::string database, std::list<std::string> targets, std::string route);
  54             Map();
  55             bool match(const std::string db) const;
  56             std::string m_dbpattern;
  57             std::list<std::string> m_targets;
  58             std::string m_route;
  59         };
  60         struct VirtualDB::Backend {
  61             mp::Session m_backend_session;
  62             std::list<std::string> m_frontend_databases;
  63             std::list<std::string> m_targets;
  64             std::string m_route;
  65             bool m_named_result_sets;
  66             int m_number_of_sets;
  67         };
  68         struct VirtualDB::Frontend {
  69             Frontend(Rep *rep);
  70             ~Frontend();
  71             mp::Session m_session;
  72             bool m_is_virtual;
  73             bool m_in_use;
  74             yazpp_1::GDU m_init_gdu;
  75             std::list<BackendPtr> m_backend_list;
  76             std::map<std::string,VirtualDB::Set> m_sets;
  77
  78             void search(Package &package, Z_APDU *apdu);
  79             void present(Package &package, Z_APDU *apdu);
  80             void scan(Package &package, Z_APDU *apdu);
  81
  82             void close(Package &package);
  83             typedef std::map<std::string,VirtualDB::Set>::iterator Sets_it;
  84
  85             void fixup_package(Package &p, BackendPtr b);
  86             void fixup_npr_record(ODR odr, Z_NamePlusRecord *npr,
  87                                   BackendPtr b);
  88             void fixup_npr_records(ODR odr, Z_Records *records,
  89                                    BackendPtr b);
  90
  91             BackendPtr lookup_backend_from_databases(
  92                 std::list<std::string> databases);
  93             BackendPtr create_backend_from_databases(
  94                 std::list<std::string> databases,
  95                 int &error_code,
  96                 std::string &failing_database);
  97
  98             BackendPtr init_backend(std::list<std::string> database,
  99                                     Package &package,
 100                                     int &error_code, std::string &addinfo);
 101             Rep *m_p;
 102         };
 103         class VirtualDB::Rep {
 104             friend class VirtualDB;
 105             friend struct Frontend;
 106
 107             FrontendPtr get_frontend(Package &package);
 108             void release_frontend(Package &package);
 109         private:
 110             std::list<VirtualDB::Map>m_maps;
 111             typedef std::map<std::string,VirtualDB::Set>::iterator Sets_it;
 112             boost::mutex m_mutex;
 113             boost::condition m_cond_session_ready;
 114             std::map<mp::Session, FrontendPtr> m_clients;
 115             bool pass_vhosts;
 116         };
 117     }
 118 }
 119
 120 yf::VirtualDB::BackendPtr yf::VirtualDB::Frontend::lookup_backend_from_databases(
 121     std::list<std::string> databases)
 122 {
 123     std::list<BackendPtr>::const_iterator map_it;
 124     map_it = m_backend_list.begin();
 125     for (; map_it != m_backend_list.end(); map_it++)
 126         if ((*map_it)->m_frontend_databases == databases)
 127             return *map_it;
 128     BackendPtr null;
 129     return null;
 130 }
 131
 132 yf::VirtualDB::BackendPtr yf::VirtualDB::Frontend::create_backend_from_databases(
 133     std::list<std::string> databases, int &error_code, std::string &addinfo)
 134 {
 135     BackendPtr b(new Backend);
 136     std::list<std::string>::const_iterator db_it = databases.begin();
 137
 138     b->m_number_of_sets = 0;
 139     b->m_frontend_databases = databases;
 140     b->m_named_result_sets = false;
 141
 142     bool first_route = true;
 143
 144     std::map<std::string,bool> targets_dedup;
 145     for (; db_it != databases.end(); db_it++)
 146     {
 147         std::list<VirtualDB::Map>::const_iterator map_it;
 148         map_it = m_p->m_maps.begin();
 149         while (map_it != m_p->m_maps.end())
 150         {
 151             if (map_it->match(*db_it))
 152                 break;
 153             map_it++;
 154         }
 155
 156         if (map_it == m_p->m_maps.end())  // database not found
 157         {
 158             error_code = YAZ_BIB1_DATABASE_DOES_NOT_EXIST;
 159             addinfo = *db_it;
 160             BackendPtr ptr;
 161             return ptr;
 162         }
 163         std::list<std::string>::const_iterator t_it =
 164             map_it->m_targets.begin();
 165         for (; t_it != map_it->m_targets.end(); t_it++) {
 166             if (!targets_dedup[*t_it])
 167             {
 168                 targets_dedup[*t_it] = true;
 169                 b->m_targets.push_back(*t_it);
 170             }
 171         }
 172
 173         // see if we have a route conflict.
 174         if (!first_route && b->m_route != map_it->m_route)
 175         {
 176             // we have a conflict..
 177             error_code =  YAZ_BIB1_COMBI_OF_SPECIFIED_DATABASES_UNSUPP;
 178             BackendPtr ptr;
 179             return ptr;
 180         }
 181         b->m_route = map_it->m_route;
 182         first_route = false;
 183     }
 184     return b;
 185 }
 186
 187 yf::VirtualDB::BackendPtr yf::VirtualDB::Frontend::init_backend(
 188     std::list<std::string> databases, mp::Package &package,
 189     int &error_code, std::string &addinfo)
 190 {
 191     BackendPtr b = create_backend_from_databases(databases, error_code,
 192                                                  addinfo);
 193     if (!b)
 194         return b;
 195     Package init_package(b->m_backend_session, package.origin());
 196     init_package.copy_filter(package);
 197
 198     mp::odr odr;
 199
 200     Z_APDU *init_apdu = zget_APDU(odr, Z_APDU_initRequest);
 201
 202     mp::util::set_vhost_otherinfo(&init_apdu->u.initRequest->otherInfo, odr,
 203                                    b->m_targets);
 204     Z_InitRequest *req = init_apdu->u.initRequest;
 205
 206     // copy stuff from Frontend Init Request
 207     Z_GDU *org_gdu = m_init_gdu.get();
 208     Z_InitRequest *org_init = org_gdu->u.z3950->u.initRequest;
 209
 210     req->idAuthentication = org_init->idAuthentication;
 211     req->implementationId = org_init->implementationId;
 212     req->implementationName = org_init->implementationName;
 213     req->implementationVersion = org_init->implementationVersion;
 214
 215     ODR_MASK_SET(req->options, Z_Options_search);
 216     ODR_MASK_SET(req->options, Z_Options_present);
 217     ODR_MASK_SET(req->options, Z_Options_namedResultSets);
 218     ODR_MASK_SET(req->options, Z_Options_scan);
 219
 220     ODR_MASK_SET(req->protocolVersion, Z_ProtocolVersion_1);
 221     ODR_MASK_SET(req->protocolVersion, Z_ProtocolVersion_2);
 222     ODR_MASK_SET(req->protocolVersion, Z_ProtocolVersion_3);
 223
 224     init_package.request() = init_apdu;
 225
 226     init_package.move(b->m_route);  // sending init
 227
 228     Z_GDU *gdu = init_package.response().get();
 229     // we hope to get an init response
 230     if (gdu && gdu->which == Z_GDU_Z3950 && gdu->u.z3950->which ==
 231         Z_APDU_initResponse)
 232     {
 233         Z_InitResponse *res = gdu->u.z3950->u.initResponse;
 234         if (ODR_MASK_GET(res->options, Z_Options_namedResultSets))
 235         {
 236             b->m_named_result_sets = true;
 237         }
 238         if (*res->result)
 239         {
 240             m_backend_list.push_back(b);
 241             return b;
 242
 243         }
 244         error_code = YAZ_BIB1_DATABASE_UNAVAILABLE;
 245         mp::util::get_init_diagnostics(res, error_code, addinfo);
 246     }
 247     if (!init_package.session().is_closed())
 248     {
 249         Package close_package(b->m_backend_session, package.origin());
 250         close_package.copy_filter(package);
 251         close_package.session().close();
 252         close_package.move(b->m_route);  // closing it
 253     }
 254     BackendPtr null;
 255     return null;
 256 }
 257
 258 void yf::VirtualDB::Frontend::search(mp::Package &package, Z_APDU *apdu_req)
 259 {
 260     Z_SearchRequest *req = apdu_req->u.searchRequest;
 261     std::string vhost;
 262     std::string resultSetId = req->resultSetName;
 263     mp::odr odr;
 264
 265     std::list<std::string> databases;
 266     int i;
 267     for (i = 0; i<req->num_databaseNames; i++)
 268         databases.push_back(req->databaseNames[i]);
 269
 270     BackendPtr b; // null for now
 271     Sets_it sets_it = m_sets.find(req->resultSetName);
 272     if (sets_it != m_sets.end())
 273     {
 274         // result set already exist
 275         // if replace indicator is off: we return diagnostic if
 276         // result set already exist.
 277         if (*req->replaceIndicator == 0)
 278         {
 279             Z_APDU *apdu =
 280                 odr.create_searchResponse(
 281                     apdu_req,
 282                     YAZ_BIB1_RESULT_SET_EXISTS_AND_REPLACE_INDICATOR_OFF,
 283                     0);
 284             package.response() = apdu;
 285
 286             return;
 287         }
 288         sets_it->second.m_backend->m_number_of_sets--;
 289
 290         // pick up any existing backend with a database match
 291         std::list<BackendPtr>::const_iterator map_it;
 292         map_it = m_backend_list.begin();
 293         for (; map_it != m_backend_list.end(); map_it++)
 294         {
 295             BackendPtr tmp = *map_it;
 296             if (tmp->m_frontend_databases == databases)
 297                 break;
 298         }
 299         if (map_it != m_backend_list.end())
 300             b = *map_it;
 301     }
 302     else
 303     {
 304         // new result set.
 305
 306         // pick up any existing database with named result sets ..
 307         // or one which has no result sets.. yet.
 308         std::list<BackendPtr>::const_iterator map_it;
 309         map_it = m_backend_list.begin();
 310         for (; map_it != m_backend_list.end(); map_it++)
 311         {
 312             BackendPtr tmp = *map_it;
 313             if (tmp->m_frontend_databases == databases &&
 314                 (tmp->m_named_result_sets ||
 315                  tmp->m_number_of_sets == 0))
 316                 break;
 317         }
 318         if (map_it != m_backend_list.end())
 319             b = *map_it;
 320     }
 321     if (!b)  // no backend yet. Must create a new one
 322     {
 323         int error_code;
 324         std::string addinfo;
 325         b = init_backend(databases, package, error_code, addinfo);
 326         if (!b)
 327         {
 328             // did not get a backend (unavailable somehow?)
 329
 330             Z_APDU *apdu =
 331                 odr.create_searchResponse(
 332                     apdu_req, error_code, addinfo.c_str());
 333             package.response() = apdu;
 334             return;
 335         }
 336     }
 337     m_sets.erase(req->resultSetName);
 338     // sending search to backend
 339     Package search_package(b->m_backend_session, package.origin());
 340
 341     search_package.copy_filter(package);
 342
 343     std::string backend_setname;
 344     if (b->m_named_result_sets)
 345     {
 346         backend_setname = std::string(req->resultSetName);
 347     }
 348     else
 349     {
 350         backend_setname = "default";
 351         req->resultSetName = odr_strdup(odr, backend_setname.c_str());
 352     }
 353
 354     // pick first targets spec and move the databases from it ..
 355     std::list<std::string>::const_iterator t_it = b->m_targets.begin();
 356     if (t_it != b->m_targets.end())
 357     {
 358         mp::util::set_databases_from_zurl(odr, *t_it,
 359                                                 &req->num_databaseNames,
 360                                                 &req->databaseNames);
 361     }
 362
 363     *req->replaceIndicator = 1;
 364
 365     search_package.request() = yazpp_1::GDU(apdu_req);
 366
 367     search_package.move(b->m_route);
 368
 369     if (search_package.session().is_closed())
 370     {
 371         package.response() = search_package.response();
 372         package.session().close();
 373         return;
 374     }
 375     b->m_number_of_sets++;
 376
 377     m_sets[resultSetId] = VirtualDB::Set(b, backend_setname);
 378     fixup_package(search_package, b);
 379     package.response() = search_package.response();
 380 }
 381
 382 yf::VirtualDB::Frontend::Frontend(Rep *rep)
 383 {
 384     m_p = rep;
 385     m_is_virtual = false;
 386 }
 387
 388 void yf::VirtualDB::Frontend::close(mp::Package &package)
 389 {
 390     std::list<BackendPtr>::const_iterator b_it;
 391
 392     for (b_it = m_backend_list.begin(); b_it != m_backend_list.end(); b_it++)
 393     {
 394         (*b_it)->m_backend_session.close();
 395         Package close_package((*b_it)->m_backend_session, package.origin());
 396         close_package.copy_filter(package);
 397         close_package.move((*b_it)->m_route);
 398     }
 399     m_backend_list.clear();
 400 }
 401
 402 yf::VirtualDB::Frontend::~Frontend()
 403 {
 404 }
 405
 406 yf::VirtualDB::FrontendPtr yf::VirtualDB::Rep::get_frontend(mp::Package &package)
 407 {
 408     boost::mutex::scoped_lock lock(m_mutex);
 409
 410     std::map<mp::Session,yf::VirtualDB::FrontendPtr>::iterator it;
 411
 412     while(true)
 413     {
 414         it = m_clients.find(package.session());
 415         if (it == m_clients.end())
 416             break;
 417
 418         if (!it->second->m_in_use)
 419         {
 420             it->second->m_in_use = true;
 421             return it->second;
 422         }
 423         m_cond_session_ready.wait(lock);
 424     }
 425     FrontendPtr f(new Frontend(this));
 426     m_clients[package.session()] = f;
 427     f->m_in_use = true;
 428     return f;
 429 }
 430
 431 void yf::VirtualDB::Rep::release_frontend(mp::Package &package)
 432 {
 433     boost::mutex::scoped_lock lock(m_mutex);
 434     std::map<mp::Session,yf::VirtualDB::FrontendPtr>::iterator it;
 435
 436     it = m_clients.find(package.session());
 437     if (it != m_clients.end())
 438     {
 439         if (package.session().is_closed())
 440         {
 441             it->second->close(package);
 442             m_clients.erase(it);
 443         }
 444         else
 445         {
 446             it->second->m_in_use = false;
 447         }
 448         m_cond_session_ready.notify_all();
 449     }
 450 }
 451
 452 yf::VirtualDB::Set::Set(BackendPtr b, std::string setname)
 453     :  m_backend(b), m_setname(setname)
 454 {
 455 }
 456
 457
 458 yf::VirtualDB::Set::Set()
 459 {
 460 }
 461
 462
 463 yf::VirtualDB::Set::~Set()
 464 {
 465 }
 466
 467 yf::VirtualDB::Map::Map(std::string database,
 468                         std::list<std::string> targets, std::string route)
 469     : m_dbpattern(database), m_targets(targets), m_route(route)
 470 {
 471 }
 472
 473 yf::VirtualDB::Map::Map()
 474 {
 475 }
 476
 477 bool yf::VirtualDB::Map::match(const std::string db) const
 478 {
 479     std::string norm_db = mp::util::database_name_normalize(db);
 480     if (yaz_match_glob(m_dbpattern.c_str(), norm_db.c_str()))
 481         return true;
 482     return false;
 483 }
 484
 485 yf::VirtualDB::VirtualDB() : m_p(new VirtualDB::Rep)
 486 {
 487     m_p->pass_vhosts = false;
 488 }
 489
 490 yf::VirtualDB::~VirtualDB() {
 491 }
 492
 493 void yf::VirtualDB::Frontend::fixup_npr_record(ODR odr, Z_NamePlusRecord *npr,
 494                                              BackendPtr b)
 495 {
 496     if (npr->databaseName)
 497     {
 498         std::string b_database = std::string(npr->databaseName);
 499
 500         // consider each of the frontend databases..
 501         std::list<std::string>::const_iterator db_it;
 502         for (db_it = b->m_frontend_databases.begin();
 503              db_it != b->m_frontend_databases.end(); db_it++)
 504         {
 505             // see which target it corresponds to.. (if any)
 506             std::list<VirtualDB::Map>::const_iterator map_it =
 507                 m_p->m_maps.begin();
 508             while (map_it != m_p->m_maps.end())
 509             {
 510                 if (map_it->match(*db_it))
 511                     break;
 512                 map_it++;
 513             }
 514             if (map_it != m_p->m_maps.end())
 515             {
 516                 std::list<std::string>::const_iterator t
 517                     = map_it->m_targets.begin();
 518                 while (t != map_it->m_targets.end())
 519                 {
 520                     if (*t == b_database)
 521                     {
 522                         npr->databaseName = odr_strdup(odr, (*db_it).c_str());
 523                         return;
 524                     }
 525                     t++;
 526                 }
 527             }
 528
 529         }
 530         db_it = b->m_frontend_databases.begin();
 531         if (db_it != b->m_frontend_databases.end())
 532         {
 533             std::string database = *db_it;
 534             npr->databaseName = odr_strdup(odr, database.c_str());
 535         }
 536     }
 537 }
 538
 539 void yf::VirtualDB::Frontend::fixup_npr_records(ODR odr, Z_Records *records,
 540                                               BackendPtr b)
 541 {
 542     if (records && records->which == Z_Records_DBOSD)
 543     {
 544         Z_NamePlusRecordList *nprlist = records->u.databaseOrSurDiagnostics;
 545         int i;
 546         for (i = 0; i < nprlist->num_records; i++)
 547         {
 548             fixup_npr_record(odr, nprlist->records[i], b);
 549         }
 550     }
 551 }
 552
 553 void yf::VirtualDB::Frontend::fixup_package(mp::Package &p, BackendPtr b)
 554 {
 555     Z_GDU *gdu = p.response().get();
 556     mp::odr odr;
 557
 558     if (gdu && gdu->which == Z_GDU_Z3950)
 559     {
 560         Z_APDU *apdu = gdu->u.z3950;
 561         if (apdu->which == Z_APDU_presentResponse)
 562         {
 563             fixup_npr_records(odr, apdu->u.presentResponse->records, b);
 564             p.response() = gdu;
 565         }
 566         else if (apdu->which == Z_APDU_searchResponse)
 567         {
 568             fixup_npr_records(odr,  apdu->u.searchResponse->records, b);
 569             p.response() = gdu;
 570         }
 571     }
 572 }
 573
 574 void yf::VirtualDB::Frontend::present(mp::Package &package, Z_APDU *apdu_req)
 575 {
 576     Z_PresentRequest *req = apdu_req->u.presentRequest;
 577     std::string resultSetId = req->resultSetId;
 578     mp::odr odr;
 579
 580     Sets_it sets_it = m_sets.find(resultSetId);
 581     if (sets_it == m_sets.end())
 582     {
 583         Z_APDU *apdu =
 584             odr.create_presentResponse(
 585                 apdu_req,
 586                 YAZ_BIB1_SPECIFIED_RESULT_SET_DOES_NOT_EXIST,
 587                 resultSetId.c_str());
 588         package.response() = apdu;
 589         return;
 590     }
 591     Session *id =
 592         new mp::Session(sets_it->second.m_backend->m_backend_session);
 593
 594     // sending present to backend
 595     Package present_package(*id, package.origin());
 596     present_package.copy_filter(package);
 597
 598     req->resultSetId = odr_strdup(odr, sets_it->second.m_setname.c_str());
 599
 600     present_package.request() = yazpp_1::GDU(apdu_req);
 601
 602     present_package.move(sets_it->second.m_backend->m_route);
 603
 604     fixup_package(present_package, sets_it->second.m_backend);
 605
 606     if (present_package.session().is_closed())
 607     {
 608         package.response() = present_package.response();
 609         package.session().close();
 610         return;
 611     }
 612     else
 613     {
 614         package.response() = present_package.response();
 615     }
 616     delete id;
 617 }
 618
 619 void yf::VirtualDB::Frontend::scan(mp::Package &package, Z_APDU *apdu_req)
 620 {
 621     Z_ScanRequest *req = apdu_req->u.scanRequest;
 622     std::string vhost;
 623     mp::odr odr;
 624
 625     std::list<std::string> databases;
 626     int i;
 627     for (i = 0; i<req->num_databaseNames; i++)
 628         databases.push_back(req->databaseNames[i]);
 629
 630     BackendPtr b;
 631     // pick up any existing backend with a database match
 632     std::list<BackendPtr>::const_iterator map_it;
 633     map_it = m_backend_list.begin();
 634     for (; map_it != m_backend_list.end(); map_it++)
 635     {
 636         BackendPtr tmp = *map_it;
 637         if (tmp->m_frontend_databases == databases)
 638             break;
 639     }
 640     if (map_it != m_backend_list.end())
 641         b = *map_it;
 642     if (!b)  // no backend yet. Must create a new one
 643     {
 644         int error_code;
 645         std::string addinfo;
 646         b = init_backend(databases, package, error_code, addinfo);
 647         if (!b)
 648         {
 649             // did not get a backend (unavailable somehow?)
 650             Z_APDU *apdu =
 651                 odr.create_scanResponse(
 652                     apdu_req, error_code, addinfo.c_str());
 653             package.response() = apdu;
 654
 655             return;
 656         }
 657     }
 658     // sending scan to backend
 659     Package scan_package(b->m_backend_session, package.origin());
 660
 661     scan_package.copy_filter(package);
 662
 663     // pick first targets spec and move the databases from it ..
 664     std::list<std::string>::const_iterator t_it = b->m_targets.begin();
 665     if (t_it != b->m_targets.end())
 666     {
 667         mp::util::set_databases_from_zurl(odr, *t_it,
 668                                                 &req->num_databaseNames,
 669                                                 &req->databaseNames);
 670     }
 671     scan_package.request() = yazpp_1::GDU(apdu_req);
 672
 673     scan_package.move(b->m_route);
 674
 675     if (scan_package.session().is_closed())
 676     {
 677         package.response() = scan_package.response();
 678         package.session().close();
 679         return;
 680     }
 681     package.response() = scan_package.response();
 682 }
 683
 684
 685 void yf::VirtualDB::add_map_db2targets(std::string db,
 686                                      std::list<std::string> targets,
 687                                      std::string route)
 688 {
 689     m_p->m_maps.push_back(
 690         VirtualDB::Map(mp::util::database_name_normalize(db), targets, route));
 691 }
 692
 693
 694 void yf::VirtualDB::add_map_db2target(std::string db,
 695                                     std::string target,
 696                                     std::string route)
 697 {
 698     std::list<std::string> targets;
 699     targets.push_back(target);
 700
 701     add_map_db2targets(db, targets, route);
 702 }
 703
 704 void yf::VirtualDB::process(mp::Package &package) const
 705 {
 706     FrontendPtr f = m_p->get_frontend(package);
 707
 708     Z_GDU *gdu = package.request().get();
 709
 710     if (gdu && gdu->which == Z_GDU_Z3950 && gdu->u.z3950->which ==
 711         Z_APDU_initRequest && !f->m_is_virtual)
 712     {
 713         Z_InitRequest *req = gdu->u.z3950->u.initRequest;
 714
 715         std::list<std::string> vhosts;
 716         mp::util::get_vhost_otherinfo(req->otherInfo, vhosts);
 717
 718         if (vhosts.size() > 0 && m_p->pass_vhosts)
 719         {
 720             package.move();
 721         }
 722         else
 723         {
 724             f->m_init_gdu = gdu;
 725
 726             mp::odr odr;
 727             Z_APDU *apdu = odr.create_initResponse(gdu->u.z3950, 0, 0);
 728             Z_InitResponse *resp = apdu->u.initResponse;
 729
 730             int i;
 731             static const int masks[] = {
 732                 Z_Options_search,
 733                 Z_Options_present,
 734                 Z_Options_namedResultSets,
 735                 Z_Options_scan,
 736                 -1
 737             };
 738             for (i = 0; masks[i] != -1; i++)
 739                 if (ODR_MASK_GET(req->options, masks[i]))
 740                     ODR_MASK_SET(resp->options, masks[i]);
 741
 742             static const int versions[] = {
 743                 Z_ProtocolVersion_1,
 744                 Z_ProtocolVersion_2,
 745                 Z_ProtocolVersion_3,
 746                 -1
 747             };
 748             for (i = 0; versions[i] != -1; i++)
 749                 if (ODR_MASK_GET(req->protocolVersion, versions[i]))
 750                     ODR_MASK_SET(resp->protocolVersion, versions[i]);
 751                 else
 752                     break;
 753
 754             package.response() = apdu;
 755             f->m_is_virtual = true;
 756         }
 757     }
 758     else if (!f->m_is_virtual)
 759         package.move();
 760     else if (gdu && gdu->which == Z_GDU_Z3950)
 761     {
 762         Z_APDU *apdu = gdu->u.z3950;
 763         if (apdu->which == Z_APDU_initRequest)
 764         {
 765             mp::odr odr;
 766
 767             package.response() = odr.create_close(
 768                 apdu,
 769                 Z_Close_protocolError,
 770                 "double init");
 771
 772             package.session().close();
 773         }
 774         else if (apdu->which == Z_APDU_searchRequest)
 775         {
 776             f->search(package, apdu);
 777         }
 778         else if (apdu->which == Z_APDU_presentRequest)
 779         {
 780             f->present(package, apdu);
 781         }
 782         else if (apdu->which == Z_APDU_scanRequest)
 783         {
 784             f->scan(package, apdu);
 785         }
 786         else if (apdu->which == Z_APDU_close)
 787         {
 788             package.session().close();
 789         }
 790         else
 791         {
 792             mp::odr odr;
 793
 794             package.response() = odr.create_close(
 795                 apdu, Z_Close_protocolError,
 796                 "unsupported APDU in filter_virt_db");
 797
 798             package.session().close();
 799         }
 800     }
 801     m_p->release_frontend(package);
 802 }
 803
 804
 805 void mp::filter::VirtualDB::configure(const xmlNode * ptr, bool test_only)
 806 {
 807     for (ptr = ptr->children; ptr; ptr = ptr->next)
 808     {
 809         if (ptr->type != XML_ELEMENT_NODE)
 810             continue;
 811         if (!strcmp((const char *) ptr->name, "pass-vhosts"))
 812         {
 813             m_p->pass_vhosts = mp::xml::get_bool(ptr->children, false);
 814         }
 815         else if (!strcmp((const char *) ptr->name, "virtual"))
 816         {
 817             std::string database;
 818             std::list<std::string> targets;
 819             xmlNode *v_node = ptr->children;
 820             for (; v_node; v_node = v_node->next)
 821             {
 822                 if (v_node->type != XML_ELEMENT_NODE)
 823                     continue;
 824
 825                 if (mp::xml::is_element_mp(v_node, "database"))
 826                     database = mp::xml::get_text(v_node);
 827                 else if (mp::xml::is_element_mp(v_node, "target"))
 828                     targets.push_back(mp::xml::get_text(v_node));
 829                 else
 830                     throw mp::filter::FilterException
 831                         ("Bad element "
 832                          + std::string((const char *) v_node->name)
 833                          + " in virtual section"
 834                             );
 835             }
 836             std::string route = mp::xml::get_route(ptr);
 837             add_map_db2targets(database, targets, route);
 838         }
 839         else
 840         {
 841             throw mp::filter::FilterException
 842                 ("Bad element "
 843                  + std::string((const char *) ptr->name)
 844                  + " in virt_db filter");
 845         }
 846     }
 847 }
 848
 849 static mp::filter::Base* filter_creator()
 850 {
 851     return new mp::filter::VirtualDB;
 852 }
 853
 854 extern "C" {
 855     struct metaproxy_1_filter_struct metaproxy_1_filter_virt_db = {
 856         0,
 857         "virt_db",
 858         filter_creator
 859     };
 860 }
 861
 862
 863 /*
 864  * Local variables:
 865  * c-basic-offset: 4
 866  * c-file-style: "Stroustrup"
 867  * indent-tabs-mode: nil
 868  * End:
 869  * vim: shiftwidth=4 tabstop=8 expandtab
 870  */
 871