src/filter_virt_db.cpp

   1 /* This file is part of Metaproxy.
   2    Copyright (C) 2005-2012 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 #include <yaz/log.h>
  35
  36 #include <map>
  37 #include <iostream>
  38
  39 namespace mp = metaproxy_1;
  40 namespace yf = mp::filter;
  41
  42 namespace metaproxy_1 {
  43     namespace filter {
  44
  45         struct VirtualDB::Set {
  46             Set(BackendPtr b, std::string setname);
  47             Set();
  48             ~Set();
  49
  50             BackendPtr m_backend;
  51             std::string m_setname;
  52         };
  53         struct VirtualDB::Map {
  54             Map(std::string database, std::list<std::string> targets, std::string route);
  55             Map(std::string database, std::string target, std::string route);
  56             Map();
  57             bool match(const std::string db) const;
  58             std::string m_dbpattern;
  59             std::list<std::string> m_targets;
  60             std::string m_route;
  61         };
  62         struct VirtualDB::Backend {
  63             mp::Session m_backend_session;
  64             std::list<std::string> m_frontend_databases;
  65             std::list<std::string> m_targets;
  66             std::string m_route;
  67             bool m_named_result_sets;
  68             int m_number_of_sets;
  69         };
  70         struct VirtualDB::Frontend {
  71             Frontend(Rep *rep);
  72             ~Frontend();
  73             mp::Session m_session;
  74             bool m_is_virtual;
  75             bool m_in_use;
  76             yazpp_1::GDU m_init_gdu;
  77             std::list<BackendPtr> m_backend_list;
  78             std::map<std::string,VirtualDB::Set> m_sets;
  79
  80             void search(Package &package, Z_APDU *apdu);
  81             void present(Package &package, Z_APDU *apdu);
  82             void scan(Package &package, Z_APDU *apdu);
  83             int relay_apdu(Package &package, Z_APDU *apdu);
  84
  85             void close(Package &package);
  86             typedef std::map<std::string,VirtualDB::Set>::iterator Sets_it;
  87
  88             void fixup_package(Package &p, BackendPtr b);
  89             void fixup_npr_record(ODR odr, Z_NamePlusRecord *npr,
  90                                   BackendPtr b);
  91             void fixup_npr_records(ODR odr, Z_Records *records,
  92                                    BackendPtr b);
  93
  94             BackendPtr lookup_backend_from_databases(
  95                 std::list<std::string> databases);
  96             BackendPtr create_backend_from_databases(
  97                 std::list<std::string> databases,
  98                 int &error_code,
  99                 std::string &failing_database);
 100
 101             BackendPtr init_backend(std::list<std::string> database,
 102                                     Package &package,
 103                                     int &error_code, std::string &addinfo);
 104             Rep *m_p;
 105         };
 106         class VirtualDB::Rep {
 107             friend class VirtualDB;
 108             friend struct Frontend;
 109
 110             FrontendPtr get_frontend(Package &package);
 111             void release_frontend(Package &package);
 112             void refresh_torus();
 113         private:
 114             std::list<VirtualDB::Map>m_maps;
 115             typedef std::map<std::string,VirtualDB::Set>::iterator Sets_it;
 116             boost::mutex m_mutex;
 117             boost::condition m_cond_session_ready;
 118             std::map<mp::Session, FrontendPtr> m_clients;
 119             bool pass_vhosts;
 120         };
 121     }
 122 }
 123
 124 yf::VirtualDB::BackendPtr yf::VirtualDB::Frontend::lookup_backend_from_databases(
 125     std::list<std::string> databases)
 126 {
 127     std::list<BackendPtr>::const_iterator map_it;
 128     map_it = m_backend_list.begin();
 129     for (; map_it != m_backend_list.end(); map_it++)
 130         if ((*map_it)->m_frontend_databases == databases)
 131             return *map_it;
 132     BackendPtr null;
 133     return null;
 134 }
 135
 136 yf::VirtualDB::BackendPtr yf::VirtualDB::Frontend::create_backend_from_databases(
 137     std::list<std::string> databases, int &error_code, std::string &addinfo)
 138 {
 139     BackendPtr b(new Backend);
 140     std::list<std::string>::const_iterator db_it = databases.begin();
 141
 142     b->m_number_of_sets = 0;
 143     b->m_frontend_databases = databases;
 144     b->m_named_result_sets = false;
 145
 146     bool first_route = true;
 147
 148     std::map<std::string,bool> targets_dedup;
 149     for (; db_it != databases.end(); db_it++)
 150     {
 151         std::list<VirtualDB::Map>::const_iterator map_it;
 152         map_it = m_p->m_maps.begin();
 153         while (map_it != m_p->m_maps.end())
 154         {
 155             if (map_it->match(*db_it))
 156                 break;
 157             map_it++;
 158         }
 159
 160         if (map_it == m_p->m_maps.end())  // database not found
 161         {
 162             error_code = YAZ_BIB1_DATABASE_DOES_NOT_EXIST;
 163             addinfo = *db_it;
 164             BackendPtr ptr;
 165             return ptr;
 166         }
 167         std::list<std::string>::const_iterator t_it =
 168             map_it->m_targets.begin();
 169         for (; t_it != map_it->m_targets.end(); t_it++) {
 170             if (!targets_dedup[*t_it])
 171             {
 172                 targets_dedup[*t_it] = true;
 173                 b->m_targets.push_back(*t_it);
 174             }
 175         }
 176
 177         // see if we have a route conflict.
 178         if (!first_route && b->m_route != map_it->m_route)
 179         {
 180             // we have a conflict.. routing must be same for all
 181             error_code =  YAZ_BIB1_COMBI_OF_SPECIFIED_DATABASES_UNSUPP;
 182             BackendPtr ptr;
 183             return ptr;
 184         }
 185         b->m_route = map_it->m_route;
 186         first_route = false;
 187     }
 188     return b;
 189 }
 190
 191 yf::VirtualDB::BackendPtr yf::VirtualDB::Frontend::init_backend(
 192     std::list<std::string> databases, mp::Package &package,
 193     int &error_code, std::string &addinfo)
 194 {
 195     BackendPtr b = create_backend_from_databases(databases, error_code,
 196                                                  addinfo);
 197     if (!b)
 198         return b;
 199     Package init_package(b->m_backend_session, package.origin());
 200     init_package.copy_filter(package);
 201
 202     mp::odr odr;
 203
 204     Z_APDU *init_apdu = zget_APDU(odr, Z_APDU_initRequest);
 205
 206     mp::util::set_vhost_otherinfo(&init_apdu->u.initRequest->otherInfo, odr,
 207                                    b->m_targets);
 208     Z_InitRequest *req = init_apdu->u.initRequest;
 209
 210     // copy stuff from Frontend Init Request
 211     Z_GDU *org_gdu = m_init_gdu.get();
 212     Z_InitRequest *org_init = org_gdu->u.z3950->u.initRequest;
 213
 214     req->idAuthentication = org_init->idAuthentication;
 215     req->implementationId = org_init->implementationId;
 216     req->implementationName = org_init->implementationName;
 217     req->implementationVersion = org_init->implementationVersion;
 218     *req->preferredMessageSize = *org_init->preferredMessageSize;
 219     *req->maximumRecordSize = *org_init->maximumRecordSize;
 220
 221     ODR_MASK_SET(req->options, Z_Options_search);
 222     ODR_MASK_SET(req->options, Z_Options_present);
 223     ODR_MASK_SET(req->options, Z_Options_namedResultSets);
 224     ODR_MASK_SET(req->options, Z_Options_scan);
 225
 226     ODR_MASK_SET(req->protocolVersion, Z_ProtocolVersion_1);
 227     ODR_MASK_SET(req->protocolVersion, Z_ProtocolVersion_2);
 228     ODR_MASK_SET(req->protocolVersion, Z_ProtocolVersion_3);
 229
 230     init_package.request() = init_apdu;
 231
 232     init_package.move(b->m_route);  // sending init
 233
 234     Z_GDU *gdu = init_package.response().get();
 235     // we hope to get an init response
 236     error_code = YAZ_BIB1_DATABASE_UNAVAILABLE;
 237     if (gdu && gdu->which == Z_GDU_Z3950
 238         && gdu->u.z3950->which == Z_APDU_initResponse)
 239     {
 240         Z_InitResponse *res = gdu->u.z3950->u.initResponse;
 241         if (ODR_MASK_GET(res->options, Z_Options_namedResultSets))
 242         {
 243             b->m_named_result_sets = true;
 244         }
 245         if (*res->result && !init_package.session().is_closed())
 246         {
 247             m_backend_list.push_back(b);
 248             return b;
 249         }
 250         mp::util::get_init_diagnostics(res, error_code, addinfo);
 251     }
 252     if (!init_package.session().is_closed())
 253     {
 254         Package close_package(b->m_backend_session, package.origin());
 255         close_package.copy_filter(package);
 256         close_package.session().close();
 257         close_package.move(b->m_route);  // closing it
 258     }
 259     BackendPtr null;
 260     return null;
 261 }
 262
 263 void yf::VirtualDB::Frontend::search(mp::Package &package, Z_APDU *apdu_req)
 264 {
 265     Z_SearchRequest *req = apdu_req->u.searchRequest;
 266     std::string vhost;
 267     std::string resultSetId = req->resultSetName;
 268     mp::odr odr;
 269
 270     std::list<std::string> databases;
 271     int i;
 272     for (i = 0; i<req->num_databaseNames; i++)
 273         databases.push_back(req->databaseNames[i]);
 274
 275     Sets_it sets_it = m_sets.find(req->resultSetName);
 276     if (sets_it != m_sets.end())
 277     {
 278         // result set already exist
 279         // if replace indicator is off: we return diagnostic if
 280         // result set already exist.
 281         if (*req->replaceIndicator == 0)
 282         {
 283             Z_APDU *apdu =
 284                 odr.create_searchResponse(
 285                     apdu_req,
 286                     YAZ_BIB1_RESULT_SET_EXISTS_AND_REPLACE_INDICATOR_OFF,
 287                     0);
 288             package.response() = apdu;
 289
 290             return;
 291         }
 292         sets_it->second.m_backend->m_number_of_sets--;
 293     }
 294     // pick up any existing database with named result sets ..
 295     // or one which has no result sets.. yet.
 296     BackendPtr b; // null for now
 297     std::list<BackendPtr>::const_iterator map_it;
 298     map_it = m_backend_list.begin();
 299     for (; map_it != m_backend_list.end(); map_it++)
 300     {
 301         BackendPtr tmp = *map_it;
 302         if (tmp->m_frontend_databases == databases &&
 303             (tmp->m_named_result_sets ||
 304              tmp->m_number_of_sets == 0))
 305         {
 306             b = *map_it;
 307             break;
 308         }
 309     }
 310     if (!b)  // no backend yet. Must create a new one
 311     {
 312         int error_code;
 313         std::string addinfo;
 314         b = init_backend(databases, package, error_code, addinfo);
 315         if (!b)
 316         {
 317             // did not get a backend (unavailable somehow?)
 318
 319             Z_APDU *apdu =
 320                 odr.create_searchResponse(
 321                     apdu_req, error_code, addinfo.c_str());
 322             package.response() = apdu;
 323             return;
 324         }
 325     }
 326     m_sets.erase(req->resultSetName);
 327     // sending search to backend
 328     Package search_package(b->m_backend_session, package.origin());
 329
 330     search_package.copy_filter(package);
 331
 332     std::string backend_setname;
 333     if (b->m_named_result_sets)
 334     {
 335         backend_setname = std::string(req->resultSetName);
 336     }
 337     else
 338     {
 339         backend_setname = "default";
 340         req->resultSetName = odr_strdup(odr, backend_setname.c_str());
 341     }
 342
 343     // pick first targets spec and move the databases from it ..
 344     std::list<std::string>::const_iterator t_it = b->m_targets.begin();
 345     if (t_it != b->m_targets.end())
 346     {
 347         mp::util::set_databases_from_zurl(odr, *t_it,
 348                                                 &req->num_databaseNames,
 349                                                 &req->databaseNames);
 350     }
 351
 352     *req->replaceIndicator = 1;
 353
 354     search_package.request() = yazpp_1::GDU(apdu_req);
 355
 356     search_package.move(b->m_route);
 357
 358     if (search_package.session().is_closed())
 359     {
 360         package.response() = search_package.response();
 361         package.session().close();
 362         return;
 363     }
 364     b->m_number_of_sets++;
 365
 366     m_sets[resultSetId] = VirtualDB::Set(b, backend_setname);
 367     fixup_package(search_package, b);
 368     package.response() = search_package.response();
 369 }
 370
 371 yf::VirtualDB::Frontend::Frontend(Rep *rep)
 372 {
 373     m_p = rep;
 374     m_is_virtual = false;
 375 }
 376
 377 void yf::VirtualDB::Frontend::close(mp::Package &package)
 378 {
 379     std::list<BackendPtr>::const_iterator b_it;
 380
 381     for (b_it = m_backend_list.begin(); b_it != m_backend_list.end(); b_it++)
 382     {
 383         (*b_it)->m_backend_session.close();
 384         Package close_package((*b_it)->m_backend_session, package.origin());
 385         close_package.copy_filter(package);
 386         close_package.move((*b_it)->m_route);
 387     }
 388     m_backend_list.clear();
 389 }
 390
 391 yf::VirtualDB::Frontend::~Frontend()
 392 {
 393 }
 394
 395 yf::VirtualDB::FrontendPtr yf::VirtualDB::Rep::get_frontend(mp::Package &package)
 396 {
 397     boost::mutex::scoped_lock lock(m_mutex);
 398
 399     std::map<mp::Session,yf::VirtualDB::FrontendPtr>::iterator it;
 400
 401     while(true)
 402     {
 403         it = m_clients.find(package.session());
 404         if (it == m_clients.end())
 405             break;
 406
 407         if (!it->second->m_in_use)
 408         {
 409             it->second->m_in_use = true;
 410             return it->second;
 411         }
 412         m_cond_session_ready.wait(lock);
 413     }
 414     FrontendPtr f(new Frontend(this));
 415     m_clients[package.session()] = f;
 416     f->m_in_use = true;
 417     return f;
 418 }
 419
 420 void yf::VirtualDB::Rep::release_frontend(mp::Package &package)
 421 {
 422     boost::mutex::scoped_lock lock(m_mutex);
 423     std::map<mp::Session,yf::VirtualDB::FrontendPtr>::iterator it;
 424
 425     it = m_clients.find(package.session());
 426     if (it != m_clients.end())
 427     {
 428         if (package.session().is_closed())
 429         {
 430             it->second->close(package);
 431             m_clients.erase(it);
 432         }
 433         else
 434         {
 435             it->second->m_in_use = false;
 436         }
 437         m_cond_session_ready.notify_all();
 438     }
 439 }
 440
 441
 442 yf::VirtualDB::Set::Set(BackendPtr b, std::string setname)
 443     :  m_backend(b), m_setname(setname)
 444 {
 445 }
 446
 447
 448 yf::VirtualDB::Set::Set()
 449 {
 450 }
 451
 452
 453 yf::VirtualDB::Set::~Set()
 454 {
 455 }
 456
 457 yf::VirtualDB::Map::Map(std::string database,
 458                         std::list<std::string> targets, std::string route)
 459     : m_dbpattern(database), m_targets(targets), m_route(route)
 460 {
 461 }
 462
 463 yf::VirtualDB::Map::Map(std::string database,
 464                         std::string target, std::string route)
 465     : m_dbpattern(database), m_route(route)
 466 {
 467     m_targets.push_back(target);
 468 }
 469
 470
 471 yf::VirtualDB::Map::Map()
 472 {
 473 }
 474
 475 bool yf::VirtualDB::Map::match(const std::string db) const
 476 {
 477     std::string norm_db = mp::util::database_name_normalize(db);
 478     if (yaz_match_glob(m_dbpattern.c_str(), norm_db.c_str()))
 479         return true;
 480     return false;
 481 }
 482
 483 yf::VirtualDB::VirtualDB() : m_p(new VirtualDB::Rep)
 484 {
 485     m_p->pass_vhosts = false;
 486 }
 487
 488 yf::VirtualDB::~VirtualDB() {
 489 }
 490
 491 void yf::VirtualDB::Frontend::fixup_npr_record(ODR odr, Z_NamePlusRecord *npr,
 492                                              BackendPtr b)
 493 {
 494     if (npr->databaseName)
 495     {
 496         std::string b_database = std::string(npr->databaseName);
 497
 498         // consider each of the frontend databases..
 499         std::list<std::string>::const_iterator db_it;
 500         for (db_it = b->m_frontend_databases.begin();
 501              db_it != b->m_frontend_databases.end(); db_it++)
 502         {
 503             // see which target it corresponds to.. (if any)
 504             std::list<VirtualDB::Map>::const_iterator map_it =
 505                 m_p->m_maps.begin();
 506             while (map_it != m_p->m_maps.end())
 507             {
 508                 if (map_it->match(*db_it))
 509                     break;
 510                 map_it++;
 511             }
 512             if (map_it != m_p->m_maps.end())
 513             {
 514                 std::list<std::string>::const_iterator t
 515                     = map_it->m_targets.begin();
 516                 while (t != map_it->m_targets.end())
 517                 {
 518                     if (*t == b_database)
 519                     {
 520                         npr->databaseName = odr_strdup(odr, (*db_it).c_str());
 521                         return;
 522                     }
 523                     t++;
 524                 }
 525             }
 526
 527         }
 528         db_it = b->m_frontend_databases.begin();
 529         if (db_it != b->m_frontend_databases.end())
 530         {
 531             std::string database = *db_it;
 532             npr->databaseName = odr_strdup(odr, database.c_str());
 533         }
 534     }
 535 }
 536
 537 void yf::VirtualDB::Frontend::fixup_npr_records(ODR odr, Z_Records *records,
 538                                               BackendPtr b)
 539 {
 540     if (records && records->which == Z_Records_DBOSD)
 541     {
 542         Z_NamePlusRecordList *nprlist = records->u.databaseOrSurDiagnostics;
 543         int i;
 544         for (i = 0; i < nprlist->num_records; i++)
 545         {
 546             fixup_npr_record(odr, nprlist->records[i], b);
 547         }
 548     }
 549 }
 550
 551 void yf::VirtualDB::Frontend::fixup_package(mp::Package &p, BackendPtr b)
 552 {
 553     Z_GDU *gdu = p.response().get();
 554     mp::odr odr;
 555
 556     if (gdu && gdu->which == Z_GDU_Z3950)
 557     {
 558         Z_APDU *apdu = gdu->u.z3950;
 559         if (apdu->which == Z_APDU_presentResponse)
 560         {
 561             fixup_npr_records(odr, apdu->u.presentResponse->records, b);
 562             p.response() = gdu;
 563         }
 564         else if (apdu->which == Z_APDU_searchResponse)
 565         {
 566             fixup_npr_records(odr,  apdu->u.searchResponse->records, b);
 567             p.response() = gdu;
 568         }
 569     }
 570 }
 571
 572 void yf::VirtualDB::Frontend::present(mp::Package &package, Z_APDU *apdu_req)
 573 {
 574     Z_PresentRequest *req = apdu_req->u.presentRequest;
 575     std::string resultSetId = req->resultSetId;
 576     mp::odr odr;
 577
 578     Sets_it sets_it = m_sets.find(resultSetId);
 579     if (sets_it == m_sets.end())
 580     {
 581         Z_APDU *apdu =
 582             odr.create_presentResponse(
 583                 apdu_req,
 584                 YAZ_BIB1_SPECIFIED_RESULT_SET_DOES_NOT_EXIST,
 585                 resultSetId.c_str());
 586         package.response() = apdu;
 587         return;
 588     }
 589     Session *id =
 590         new mp::Session(sets_it->second.m_backend->m_backend_session);
 591
 592     // sending present to backend
 593     Package present_package(*id, package.origin());
 594     present_package.copy_filter(package);
 595
 596     req->resultSetId = odr_strdup(odr, sets_it->second.m_setname.c_str());
 597
 598     present_package.request() = yazpp_1::GDU(apdu_req);
 599
 600     present_package.move(sets_it->second.m_backend->m_route);
 601
 602     fixup_package(present_package, sets_it->second.m_backend);
 603
 604     if (present_package.session().is_closed())
 605     {
 606         package.response() = present_package.response();
 607         package.session().close();
 608         return;
 609     }
 610     else
 611     {
 612         package.response() = present_package.response();
 613     }
 614     delete id;
 615 }
 616
 617 int yf::VirtualDB::Frontend::relay_apdu(mp::Package &package, Z_APDU *apdu_req)
 618 {
 619     int no = 0;
 620     std::list<BackendPtr>::const_iterator map_it;
 621     map_it = m_backend_list.begin();
 622     for (; map_it != m_backend_list.end(); map_it++)
 623     {
 624         BackendPtr b = *map_it;
 625
 626         Package relay_package(b->m_backend_session, package.origin());
 627         relay_package.copy_filter(package);
 628
 629         relay_package.request() = yazpp_1::GDU(apdu_req);
 630
 631         relay_package.move(b->m_route);
 632         package.response() = relay_package.response();
 633         no++;
 634     }
 635     return no;
 636 }
 637
 638 void yf::VirtualDB::Frontend::scan(mp::Package &package, Z_APDU *apdu_req)
 639 {
 640     Z_ScanRequest *req = apdu_req->u.scanRequest;
 641     std::string vhost;
 642     mp::odr odr;
 643
 644     std::list<std::string> databases;
 645     int i;
 646     for (i = 0; i<req->num_databaseNames; i++)
 647         databases.push_back(req->databaseNames[i]);
 648
 649     BackendPtr b;
 650     // pick up any existing backend with a database match
 651     std::list<BackendPtr>::const_iterator map_it;
 652     map_it = m_backend_list.begin();
 653     for (; map_it != m_backend_list.end(); map_it++)
 654     {
 655         BackendPtr tmp = *map_it;
 656         if (tmp->m_frontend_databases == databases)
 657             break;
 658     }
 659     if (map_it != m_backend_list.end())
 660         b = *map_it;
 661     if (!b)  // no backend yet. Must create a new one
 662     {
 663         int error_code;
 664         std::string addinfo;
 665         b = init_backend(databases, package, error_code, addinfo);
 666         if (!b)
 667         {
 668             // did not get a backend (unavailable somehow?)
 669             Z_APDU *apdu =
 670                 odr.create_scanResponse(
 671                     apdu_req, error_code, addinfo.c_str());
 672             package.response() = apdu;
 673
 674             return;
 675         }
 676     }
 677     // sending scan to backend
 678     Package scan_package(b->m_backend_session, package.origin());
 679
 680     scan_package.copy_filter(package);
 681
 682     // pick first targets spec and move the databases from it ..
 683     std::list<std::string>::const_iterator t_it = b->m_targets.begin();
 684     if (t_it != b->m_targets.end())
 685     {
 686         mp::util::set_databases_from_zurl(odr, *t_it,
 687                                                 &req->num_databaseNames,
 688                                                 &req->databaseNames);
 689     }
 690
 691     scan_package.request() = yazpp_1::GDU(apdu_req);
 692
 693     scan_package.move(b->m_route);
 694
 695     if (scan_package.session().is_closed())
 696     {
 697         package.response() = scan_package.response();
 698         package.session().close();
 699         return;
 700     }
 701     package.response() = scan_package.response();
 702 }
 703
 704
 705 void yf::VirtualDB::add_map_db2targets(std::string db,
 706                                        std::list<std::string> targets,
 707                                        std::string route)
 708 {
 709     m_p->m_maps.push_back(
 710         VirtualDB::Map(mp::util::database_name_normalize(db), targets, route));
 711 }
 712
 713
 714 void yf::VirtualDB::add_map_db2target(std::string db,
 715                                       std::string target,
 716                                       std::string route)
 717
 718 {
 719     m_p->m_maps.push_back(
 720         VirtualDB::Map(mp::util::database_name_normalize(db), target, route));
 721 }
 722
 723 void yf::VirtualDB::process(mp::Package &package) const
 724 {
 725     FrontendPtr f = m_p->get_frontend(package);
 726
 727     Z_GDU *gdu = package.request().get();
 728
 729     if (gdu && gdu->which == Z_GDU_Z3950 && gdu->u.z3950->which ==
 730         Z_APDU_initRequest && !f->m_is_virtual)
 731     {
 732         Z_InitRequest *req = gdu->u.z3950->u.initRequest;
 733
 734         std::list<std::string> vhosts;
 735         mp::util::get_vhost_otherinfo(req->otherInfo, vhosts);
 736
 737         if (vhosts.size() > 0 && m_p->pass_vhosts)
 738         {
 739             package.move();
 740         }
 741         else
 742         {
 743             f->m_init_gdu = gdu;
 744
 745             mp::odr odr;
 746             Z_APDU *apdu = odr.create_initResponse(gdu->u.z3950, 0, 0);
 747             Z_InitResponse *resp = apdu->u.initResponse;
 748
 749             int i;
 750             static const int masks[] = {
 751                 Z_Options_search,
 752                 Z_Options_present,
 753                 Z_Options_namedResultSets,
 754                 Z_Options_scan,
 755                 -1
 756             };
 757             for (i = 0; masks[i] != -1; i++)
 758                 if (ODR_MASK_GET(req->options, masks[i]))
 759                     ODR_MASK_SET(resp->options, masks[i]);
 760
 761             static const int versions[] = {
 762                 Z_ProtocolVersion_1,
 763                 Z_ProtocolVersion_2,
 764                 Z_ProtocolVersion_3,
 765                 -1
 766             };
 767             for (i = 0; versions[i] != -1; i++)
 768                 if (ODR_MASK_GET(req->protocolVersion, versions[i]))
 769                     ODR_MASK_SET(resp->protocolVersion, versions[i]);
 770                 else
 771                     break;
 772
 773             *resp->preferredMessageSize = *req->preferredMessageSize;
 774             *resp->maximumRecordSize = *req->maximumRecordSize;
 775
 776             package.response() = apdu;
 777             f->m_is_virtual = true;
 778         }
 779     }
 780     else if (!f->m_is_virtual)
 781         package.move();
 782     else if (gdu && gdu->which == Z_GDU_Z3950)
 783     {
 784         Z_APDU *apdu = gdu->u.z3950;
 785         if (apdu->which == Z_APDU_initRequest)
 786         {
 787             mp::odr odr;
 788
 789             package.response() = odr.create_close(
 790                 apdu,
 791                 Z_Close_protocolError,
 792                 "double init");
 793
 794             package.session().close();
 795         }
 796         else if (apdu->which == Z_APDU_searchRequest)
 797         {
 798             f->search(package, apdu);
 799         }
 800         else if (apdu->which == Z_APDU_presentRequest)
 801         {
 802             f->present(package, apdu);
 803         }
 804         else if (apdu->which == Z_APDU_scanRequest)
 805         {
 806             f->scan(package, apdu);
 807         }
 808         else if (apdu->which == Z_APDU_close)
 809         {
 810             if (f->relay_apdu(package, apdu) == 0)
 811             {
 812                 mp::odr odr;
 813
 814                 package.response() = odr.create_close(
 815                     apdu, Z_Close_finished, "virt_db");
 816
 817                 package.session().close();
 818             }
 819         }
 820         else
 821         {
 822             mp::odr odr;
 823
 824             package.response() = odr.create_close(
 825                 apdu, Z_Close_protocolError,
 826                 "unsupported APDU in filter_virt_db");
 827
 828             package.session().close();
 829         }
 830     }
 831     m_p->release_frontend(package);
 832 }
 833
 834 void mp::filter::VirtualDB::configure(const xmlNode * ptr, bool test_only,
 835                                       const char *path)
 836 {
 837     for (ptr = ptr->children; ptr; ptr = ptr->next)
 838     {
 839         if (ptr->type != XML_ELEMENT_NODE)
 840             continue;
 841         if (!strcmp((const char *) ptr->name, "pass-vhosts"))
 842         {
 843             m_p->pass_vhosts = mp::xml::get_bool(ptr, false);
 844         }
 845         else if (!strcmp((const char *) ptr->name, "virtual"))
 846         {
 847             std::string database;
 848             std::list<std::string> targets;
 849             xmlNode *v_node = ptr->children;
 850             for (; v_node; v_node = v_node->next)
 851             {
 852                 if (v_node->type != XML_ELEMENT_NODE)
 853                     continue;
 854
 855                 if (mp::xml::is_element_mp(v_node, "database"))
 856                     database = mp::xml::get_text(v_node);
 857                 else if (mp::xml::is_element_mp(v_node, "target"))
 858                     targets.push_back(mp::xml::get_text(v_node));
 859                 else
 860                     throw mp::filter::FilterException
 861                         ("Bad element "
 862                          + std::string((const char *) v_node->name)
 863                          + " in virtual section"
 864                             );
 865             }
 866             std::string route = mp::xml::get_route(ptr);
 867
 868             VirtualDB::Map vmap(mp::util::database_name_normalize(database),
 869                                 targets, route);
 870             m_p->m_maps.push_back(vmap);
 871         }
 872         else
 873         {
 874             throw mp::filter::FilterException
 875                 ("Bad element "
 876                  + std::string((const char *) ptr->name)
 877                  + " in virt_db filter");
 878         }
 879     }
 880 }
 881
 882 static mp::filter::Base* filter_creator()
 883 {
 884     return new mp::filter::VirtualDB;
 885 }
 886
 887 extern "C" {
 888     struct metaproxy_1_filter_struct metaproxy_1_filter_virt_db = {
 889         0,
 890         "virt_db",
 891         filter_creator
 892     };
 893 }
 894
 895
 896 /*
 897  * Local variables:
 898  * c-basic-offset: 4
 899  * c-file-style: "Stroustrup"
 900  * indent-tabs-mode: nil
 901  * End:
 902  * vim: shiftwidth=4 tabstop=8 expandtab
 903  */
 904