src/filter_virt_db.cpp

   1 /* This file is part of Metaproxy.
   2    Copyright (C) 2005-2011 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();
  56             bool match(const std::string db) const;
  57             std::string m_dbpattern;
  58             std::list<std::string> m_targets;
  59             std::string m_route;
  60         };
  61         struct VirtualDB::Backend {
  62             mp::Session m_backend_session;
  63             std::list<std::string> m_frontend_databases;
  64             std::list<std::string> m_targets;
  65             std::string m_route;
  66             bool m_named_result_sets;
  67             int m_number_of_sets;
  68         };
  69         struct VirtualDB::Frontend {
  70             Frontend(Rep *rep);
  71             ~Frontend();
  72             mp::Session m_session;
  73             bool m_is_virtual;
  74             bool m_in_use;
  75             yazpp_1::GDU m_init_gdu;
  76             std::list<BackendPtr> m_backend_list;
  77             std::map<std::string,VirtualDB::Set> m_sets;
  78
  79             void search(Package &package, Z_APDU *apdu);
  80             void present(Package &package, Z_APDU *apdu);
  81             void scan(Package &package, Z_APDU *apdu);
  82
  83             void close(Package &package);
  84             typedef std::map<std::string,VirtualDB::Set>::iterator Sets_it;
  85
  86             void fixup_package(Package &p, BackendPtr b);
  87             void fixup_npr_record(ODR odr, Z_NamePlusRecord *npr,
  88                                   BackendPtr b);
  89             void fixup_npr_records(ODR odr, Z_Records *records,
  90                                    BackendPtr b);
  91
  92             BackendPtr lookup_backend_from_databases(
  93                 std::list<std::string> databases);
  94             BackendPtr create_backend_from_databases(
  95                 std::list<std::string> databases,
  96                 int &error_code,
  97                 std::string &failing_database);
  98
  99             BackendPtr init_backend(std::list<std::string> database,
 100                                     Package &package,
 101                                     int &error_code, std::string &addinfo);
 102             Rep *m_p;
 103         };
 104         class VirtualDB::Rep {
 105             friend class VirtualDB;
 106             friend struct Frontend;
 107
 108             FrontendPtr get_frontend(Package &package);
 109             void release_frontend(Package &package);
 110         private:
 111             std::list<VirtualDB::Map>m_maps;
 112             typedef std::map<std::string,VirtualDB::Set>::iterator Sets_it;
 113             boost::mutex m_mutex;
 114             boost::condition m_cond_session_ready;
 115             std::map<mp::Session, FrontendPtr> m_clients;
 116             bool pass_vhosts;
 117         };
 118     }
 119 }
 120
 121 yf::VirtualDB::BackendPtr yf::VirtualDB::Frontend::lookup_backend_from_databases(
 122     std::list<std::string> databases)
 123 {
 124     std::list<BackendPtr>::const_iterator map_it;
 125     map_it = m_backend_list.begin();
 126     for (; map_it != m_backend_list.end(); map_it++)
 127         if ((*map_it)->m_frontend_databases == databases)
 128             return *map_it;
 129     BackendPtr null;
 130     return null;
 131 }
 132
 133 yf::VirtualDB::BackendPtr yf::VirtualDB::Frontend::create_backend_from_databases(
 134     std::list<std::string> databases, int &error_code, std::string &addinfo)
 135 {
 136     BackendPtr b(new Backend);
 137     std::list<std::string>::const_iterator db_it = databases.begin();
 138
 139     b->m_number_of_sets = 0;
 140     b->m_frontend_databases = databases;
 141     b->m_named_result_sets = false;
 142
 143     bool first_route = true;
 144
 145     std::map<std::string,bool> targets_dedup;
 146     for (; db_it != databases.end(); db_it++)
 147     {
 148         std::list<VirtualDB::Map>::const_iterator map_it;
 149         map_it = m_p->m_maps.begin();
 150         while (map_it != m_p->m_maps.end())
 151         {
 152             if (map_it->match(*db_it))
 153                 break;
 154             map_it++;
 155         }
 156
 157         if (map_it == m_p->m_maps.end())  // database not found
 158         {
 159             error_code = YAZ_BIB1_DATABASE_DOES_NOT_EXIST;
 160             addinfo = *db_it;
 161             BackendPtr ptr;
 162             return ptr;
 163         }
 164         std::list<std::string>::const_iterator t_it =
 165             map_it->m_targets.begin();
 166         for (; t_it != map_it->m_targets.end(); t_it++) {
 167             if (!targets_dedup[*t_it])
 168             {
 169                 targets_dedup[*t_it] = true;
 170                 b->m_targets.push_back(*t_it);
 171             }
 172         }
 173
 174         // see if we have a route conflict.
 175         if (!first_route && b->m_route != map_it->m_route)
 176         {
 177             // we have a conflict..
 178             error_code =  YAZ_BIB1_COMBI_OF_SPECIFIED_DATABASES_UNSUPP;
 179             BackendPtr ptr;
 180             return ptr;
 181         }
 182         b->m_route = map_it->m_route;
 183         first_route = false;
 184     }
 185     return b;
 186 }
 187
 188 yf::VirtualDB::BackendPtr yf::VirtualDB::Frontend::init_backend(
 189     std::list<std::string> databases, mp::Package &package,
 190     int &error_code, std::string &addinfo)
 191 {
 192     BackendPtr b = create_backend_from_databases(databases, error_code,
 193                                                  addinfo);
 194     if (!b)
 195         return b;
 196     Package init_package(b->m_backend_session, package.origin());
 197     init_package.copy_filter(package);
 198
 199     mp::odr odr;
 200
 201     Z_APDU *init_apdu = zget_APDU(odr, Z_APDU_initRequest);
 202
 203     mp::util::set_vhost_otherinfo(&init_apdu->u.initRequest->otherInfo, odr,
 204                                    b->m_targets);
 205     Z_InitRequest *req = init_apdu->u.initRequest;
 206
 207     // copy stuff from Frontend Init Request
 208     Z_GDU *org_gdu = m_init_gdu.get();
 209     Z_InitRequest *org_init = org_gdu->u.z3950->u.initRequest;
 210
 211     req->idAuthentication = org_init->idAuthentication;
 212     req->implementationId = org_init->implementationId;
 213     req->implementationName = org_init->implementationName;
 214     req->implementationVersion = org_init->implementationVersion;
 215
 216     ODR_MASK_SET(req->options, Z_Options_search);
 217     ODR_MASK_SET(req->options, Z_Options_present);
 218     ODR_MASK_SET(req->options, Z_Options_namedResultSets);
 219     ODR_MASK_SET(req->options, Z_Options_scan);
 220
 221     ODR_MASK_SET(req->protocolVersion, Z_ProtocolVersion_1);
 222     ODR_MASK_SET(req->protocolVersion, Z_ProtocolVersion_2);
 223     ODR_MASK_SET(req->protocolVersion, Z_ProtocolVersion_3);
 224
 225     init_package.request() = init_apdu;
 226
 227     init_package.move(b->m_route);  // sending init
 228
 229     Z_GDU *gdu = init_package.response().get();
 230     // we hope to get an init response
 231     error_code = YAZ_BIB1_DATABASE_UNAVAILABLE;
 232     if (gdu && gdu->which == Z_GDU_Z3950
 233         && gdu->u.z3950->which == Z_APDU_initResponse
 234         && *gdu->u.z3950->u.initResponse->result)
 235     {
 236         Z_InitResponse *res = gdu->u.z3950->u.initResponse;
 237         if (ODR_MASK_GET(res->options, Z_Options_namedResultSets))
 238         {
 239             b->m_named_result_sets = true;
 240         }
 241         if (*res->result && !init_package.session().is_closed())
 242         {
 243             m_backend_list.push_back(b);
 244             return b;
 245         }
 246         mp::util::get_init_diagnostics(res, error_code, addinfo);
 247     }
 248     if (!init_package.session().is_closed())
 249     {
 250         Package close_package(b->m_backend_session, package.origin());
 251         close_package.copy_filter(package);
 252         close_package.session().close();
 253         close_package.move(b->m_route);  // closing it
 254     }
 255     BackendPtr null;
 256     return null;
 257 }
 258
 259 void yf::VirtualDB::Frontend::search(mp::Package &package, Z_APDU *apdu_req)
 260 {
 261     Z_SearchRequest *req = apdu_req->u.searchRequest;
 262     std::string vhost;
 263     std::string resultSetId = req->resultSetName;
 264     mp::odr odr;
 265
 266     std::list<std::string> databases;
 267     int i;
 268     for (i = 0; i<req->num_databaseNames; i++)
 269         databases.push_back(req->databaseNames[i]);
 270
 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 database with named result sets ..
 291     // or one which has no result sets.. yet.
 292     BackendPtr b; // null for now
 293     std::list<BackendPtr>::const_iterator map_it;
 294     map_it = m_backend_list.begin();
 295     for (; map_it != m_backend_list.end(); map_it++)
 296     {
 297         BackendPtr tmp = *map_it;
 298         if (tmp->m_frontend_databases == databases &&
 299             (tmp->m_named_result_sets ||
 300              tmp->m_number_of_sets == 0))
 301         {
 302             b = *map_it;
 303             break;
 304         }
 305     }
 306     if (!b)  // no backend yet. Must create a new one
 307     {
 308         int error_code;
 309         std::string addinfo;
 310         b = init_backend(databases, package, error_code, addinfo);
 311         if (!b)
 312         {
 313             // did not get a backend (unavailable somehow?)
 314
 315             Z_APDU *apdu =
 316                 odr.create_searchResponse(
 317                     apdu_req, error_code, addinfo.c_str());
 318             package.response() = apdu;
 319             return;
 320         }
 321     }
 322     m_sets.erase(req->resultSetName);
 323     // sending search to backend
 324     Package search_package(b->m_backend_session, package.origin());
 325
 326     search_package.copy_filter(package);
 327
 328     std::string backend_setname;
 329     if (b->m_named_result_sets)
 330     {
 331         backend_setname = std::string(req->resultSetName);
 332     }
 333     else
 334     {
 335         backend_setname = "default";
 336         req->resultSetName = odr_strdup(odr, backend_setname.c_str());
 337     }
 338
 339     // pick first targets spec and move the databases from it ..
 340     std::list<std::string>::const_iterator t_it = b->m_targets.begin();
 341     if (t_it != b->m_targets.end())
 342     {
 343         mp::util::set_databases_from_zurl(odr, *t_it,
 344                                                 &req->num_databaseNames,
 345                                                 &req->databaseNames);
 346     }
 347
 348     *req->replaceIndicator = 1;
 349
 350     search_package.request() = yazpp_1::GDU(apdu_req);
 351
 352     search_package.move(b->m_route);
 353
 354     if (search_package.session().is_closed())
 355     {
 356         package.response() = search_package.response();
 357         package.session().close();
 358         return;
 359     }
 360     b->m_number_of_sets++;
 361
 362     m_sets[resultSetId] = VirtualDB::Set(b, backend_setname);
 363     fixup_package(search_package, b);
 364     package.response() = search_package.response();
 365 }
 366
 367 yf::VirtualDB::Frontend::Frontend(Rep *rep)
 368 {
 369     m_p = rep;
 370     m_is_virtual = false;
 371 }
 372
 373 void yf::VirtualDB::Frontend::close(mp::Package &package)
 374 {
 375     std::list<BackendPtr>::const_iterator b_it;
 376
 377     for (b_it = m_backend_list.begin(); b_it != m_backend_list.end(); b_it++)
 378     {
 379         (*b_it)->m_backend_session.close();
 380         Package close_package((*b_it)->m_backend_session, package.origin());
 381         close_package.copy_filter(package);
 382         close_package.move((*b_it)->m_route);
 383     }
 384     m_backend_list.clear();
 385 }
 386
 387 yf::VirtualDB::Frontend::~Frontend()
 388 {
 389 }
 390
 391 yf::VirtualDB::FrontendPtr yf::VirtualDB::Rep::get_frontend(mp::Package &package)
 392 {
 393     boost::mutex::scoped_lock lock(m_mutex);
 394
 395     std::map<mp::Session,yf::VirtualDB::FrontendPtr>::iterator it;
 396
 397     while(true)
 398     {
 399         it = m_clients.find(package.session());
 400         if (it == m_clients.end())
 401             break;
 402
 403         if (!it->second->m_in_use)
 404         {
 405             it->second->m_in_use = true;
 406             return it->second;
 407         }
 408         m_cond_session_ready.wait(lock);
 409     }
 410     FrontendPtr f(new Frontend(this));
 411     m_clients[package.session()] = f;
 412     f->m_in_use = true;
 413     return f;
 414 }
 415
 416 void yf::VirtualDB::Rep::release_frontend(mp::Package &package)
 417 {
 418     boost::mutex::scoped_lock lock(m_mutex);
 419     std::map<mp::Session,yf::VirtualDB::FrontendPtr>::iterator it;
 420
 421     it = m_clients.find(package.session());
 422     if (it != m_clients.end())
 423     {
 424         if (package.session().is_closed())
 425         {
 426             it->second->close(package);
 427             m_clients.erase(it);
 428         }
 429         else
 430         {
 431             it->second->m_in_use = false;
 432         }
 433         m_cond_session_ready.notify_all();
 434     }
 435 }
 436
 437 yf::VirtualDB::Set::Set(BackendPtr b, std::string setname)
 438     :  m_backend(b), m_setname(setname)
 439 {
 440 }
 441
 442
 443 yf::VirtualDB::Set::Set()
 444 {
 445 }
 446
 447
 448 yf::VirtualDB::Set::~Set()
 449 {
 450 }
 451
 452 yf::VirtualDB::Map::Map(std::string database,
 453                         std::list<std::string> targets, std::string route)
 454     : m_dbpattern(database), m_targets(targets), m_route(route)
 455 {
 456 }
 457
 458 yf::VirtualDB::Map::Map()
 459 {
 460 }
 461
 462 bool yf::VirtualDB::Map::match(const std::string db) const
 463 {
 464     std::string norm_db = mp::util::database_name_normalize(db);
 465     if (yaz_match_glob(m_dbpattern.c_str(), norm_db.c_str()))
 466         return true;
 467     return false;
 468 }
 469
 470 yf::VirtualDB::VirtualDB() : m_p(new VirtualDB::Rep)
 471 {
 472     m_p->pass_vhosts = false;
 473 }
 474
 475 yf::VirtualDB::~VirtualDB() {
 476 }
 477
 478 void yf::VirtualDB::Frontend::fixup_npr_record(ODR odr, Z_NamePlusRecord *npr,
 479                                              BackendPtr b)
 480 {
 481     if (npr->databaseName)
 482     {
 483         std::string b_database = std::string(npr->databaseName);
 484
 485         // consider each of the frontend databases..
 486         std::list<std::string>::const_iterator db_it;
 487         for (db_it = b->m_frontend_databases.begin();
 488              db_it != b->m_frontend_databases.end(); db_it++)
 489         {
 490             // see which target it corresponds to.. (if any)
 491             std::list<VirtualDB::Map>::const_iterator map_it =
 492                 m_p->m_maps.begin();
 493             while (map_it != m_p->m_maps.end())
 494             {
 495                 if (map_it->match(*db_it))
 496                     break;
 497                 map_it++;
 498             }
 499             if (map_it != m_p->m_maps.end())
 500             {
 501                 std::list<std::string>::const_iterator t
 502                     = map_it->m_targets.begin();
 503                 while (t != map_it->m_targets.end())
 504                 {
 505                     if (*t == b_database)
 506                     {
 507                         npr->databaseName = odr_strdup(odr, (*db_it).c_str());
 508                         return;
 509                     }
 510                     t++;
 511                 }
 512             }
 513
 514         }
 515         db_it = b->m_frontend_databases.begin();
 516         if (db_it != b->m_frontend_databases.end())
 517         {
 518             std::string database = *db_it;
 519             npr->databaseName = odr_strdup(odr, database.c_str());
 520         }
 521     }
 522 }
 523
 524 void yf::VirtualDB::Frontend::fixup_npr_records(ODR odr, Z_Records *records,
 525                                               BackendPtr b)
 526 {
 527     if (records && records->which == Z_Records_DBOSD)
 528     {
 529         Z_NamePlusRecordList *nprlist = records->u.databaseOrSurDiagnostics;
 530         int i;
 531         for (i = 0; i < nprlist->num_records; i++)
 532         {
 533             fixup_npr_record(odr, nprlist->records[i], b);
 534         }
 535     }
 536 }
 537
 538 void yf::VirtualDB::Frontend::fixup_package(mp::Package &p, BackendPtr b)
 539 {
 540     Z_GDU *gdu = p.response().get();
 541     mp::odr odr;
 542
 543     if (gdu && gdu->which == Z_GDU_Z3950)
 544     {
 545         Z_APDU *apdu = gdu->u.z3950;
 546         if (apdu->which == Z_APDU_presentResponse)
 547         {
 548             fixup_npr_records(odr, apdu->u.presentResponse->records, b);
 549             p.response() = gdu;
 550         }
 551         else if (apdu->which == Z_APDU_searchResponse)
 552         {
 553             fixup_npr_records(odr,  apdu->u.searchResponse->records, b);
 554             p.response() = gdu;
 555         }
 556     }
 557 }
 558
 559 void yf::VirtualDB::Frontend::present(mp::Package &package, Z_APDU *apdu_req)
 560 {
 561     Z_PresentRequest *req = apdu_req->u.presentRequest;
 562     std::string resultSetId = req->resultSetId;
 563     mp::odr odr;
 564
 565     Sets_it sets_it = m_sets.find(resultSetId);
 566     if (sets_it == m_sets.end())
 567     {
 568         Z_APDU *apdu =
 569             odr.create_presentResponse(
 570                 apdu_req,
 571                 YAZ_BIB1_SPECIFIED_RESULT_SET_DOES_NOT_EXIST,
 572                 resultSetId.c_str());
 573         package.response() = apdu;
 574         return;
 575     }
 576     Session *id =
 577         new mp::Session(sets_it->second.m_backend->m_backend_session);
 578
 579     // sending present to backend
 580     Package present_package(*id, package.origin());
 581     present_package.copy_filter(package);
 582
 583     req->resultSetId = odr_strdup(odr, sets_it->second.m_setname.c_str());
 584
 585     present_package.request() = yazpp_1::GDU(apdu_req);
 586
 587     present_package.move(sets_it->second.m_backend->m_route);
 588
 589     fixup_package(present_package, sets_it->second.m_backend);
 590
 591     if (present_package.session().is_closed())
 592     {
 593         package.response() = present_package.response();
 594         package.session().close();
 595         return;
 596     }
 597     else
 598     {
 599         package.response() = present_package.response();
 600     }
 601     delete id;
 602 }
 603
 604 void yf::VirtualDB::Frontend::scan(mp::Package &package, Z_APDU *apdu_req)
 605 {
 606     Z_ScanRequest *req = apdu_req->u.scanRequest;
 607     std::string vhost;
 608     mp::odr odr;
 609
 610     std::list<std::string> databases;
 611     int i;
 612     for (i = 0; i<req->num_databaseNames; i++)
 613         databases.push_back(req->databaseNames[i]);
 614
 615     BackendPtr b;
 616     // pick up any existing backend with a database match
 617     std::list<BackendPtr>::const_iterator map_it;
 618     map_it = m_backend_list.begin();
 619     for (; map_it != m_backend_list.end(); map_it++)
 620     {
 621         BackendPtr tmp = *map_it;
 622         if (tmp->m_frontend_databases == databases)
 623             break;
 624     }
 625     if (map_it != m_backend_list.end())
 626         b = *map_it;
 627     if (!b)  // no backend yet. Must create a new one
 628     {
 629         int error_code;
 630         std::string addinfo;
 631         b = init_backend(databases, package, error_code, addinfo);
 632         if (!b)
 633         {
 634             // did not get a backend (unavailable somehow?)
 635             Z_APDU *apdu =
 636                 odr.create_scanResponse(
 637                     apdu_req, error_code, addinfo.c_str());
 638             package.response() = apdu;
 639
 640             return;
 641         }
 642     }
 643     // sending scan to backend
 644     Package scan_package(b->m_backend_session, package.origin());
 645
 646     scan_package.copy_filter(package);
 647
 648     // pick first targets spec and move the databases from it ..
 649     std::list<std::string>::const_iterator t_it = b->m_targets.begin();
 650     if (t_it != b->m_targets.end())
 651     {
 652         mp::util::set_databases_from_zurl(odr, *t_it,
 653                                                 &req->num_databaseNames,
 654                                                 &req->databaseNames);
 655     }
 656     scan_package.request() = yazpp_1::GDU(apdu_req);
 657
 658     scan_package.move(b->m_route);
 659
 660     if (scan_package.session().is_closed())
 661     {
 662         package.response() = scan_package.response();
 663         package.session().close();
 664         return;
 665     }
 666     package.response() = scan_package.response();
 667 }
 668
 669
 670 void yf::VirtualDB::add_map_db2targets(std::string db,
 671                                      std::list<std::string> targets,
 672                                      std::string route)
 673 {
 674     m_p->m_maps.push_back(
 675         VirtualDB::Map(mp::util::database_name_normalize(db), targets, route));
 676 }
 677
 678
 679 void yf::VirtualDB::add_map_db2target(std::string db,
 680                                     std::string target,
 681                                     std::string route)
 682 {
 683     std::list<std::string> targets;
 684     targets.push_back(target);
 685
 686     add_map_db2targets(db, targets, route);
 687 }
 688
 689 void yf::VirtualDB::process(mp::Package &package) const
 690 {
 691     FrontendPtr f = m_p->get_frontend(package);
 692
 693     Z_GDU *gdu = package.request().get();
 694
 695     if (gdu && gdu->which == Z_GDU_Z3950 && gdu->u.z3950->which ==
 696         Z_APDU_initRequest && !f->m_is_virtual)
 697     {
 698         Z_InitRequest *req = gdu->u.z3950->u.initRequest;
 699
 700         std::list<std::string> vhosts;
 701         mp::util::get_vhost_otherinfo(req->otherInfo, vhosts);
 702
 703         if (vhosts.size() > 0 && m_p->pass_vhosts)
 704         {
 705             package.move();
 706         }
 707         else
 708         {
 709             f->m_init_gdu = gdu;
 710
 711             mp::odr odr;
 712             Z_APDU *apdu = odr.create_initResponse(gdu->u.z3950, 0, 0);
 713             Z_InitResponse *resp = apdu->u.initResponse;
 714
 715             int i;
 716             static const int masks[] = {
 717                 Z_Options_search,
 718                 Z_Options_present,
 719                 Z_Options_namedResultSets,
 720                 Z_Options_scan,
 721                 -1
 722             };
 723             for (i = 0; masks[i] != -1; i++)
 724                 if (ODR_MASK_GET(req->options, masks[i]))
 725                     ODR_MASK_SET(resp->options, masks[i]);
 726
 727             static const int versions[] = {
 728                 Z_ProtocolVersion_1,
 729                 Z_ProtocolVersion_2,
 730                 Z_ProtocolVersion_3,
 731                 -1
 732             };
 733             for (i = 0; versions[i] != -1; i++)
 734                 if (ODR_MASK_GET(req->protocolVersion, versions[i]))
 735                     ODR_MASK_SET(resp->protocolVersion, versions[i]);
 736                 else
 737                     break;
 738
 739             package.response() = apdu;
 740             f->m_is_virtual = true;
 741         }
 742     }
 743     else if (!f->m_is_virtual)
 744         package.move();
 745     else if (gdu && gdu->which == Z_GDU_Z3950)
 746     {
 747         Z_APDU *apdu = gdu->u.z3950;
 748         if (apdu->which == Z_APDU_initRequest)
 749         {
 750             mp::odr odr;
 751
 752             package.response() = odr.create_close(
 753                 apdu,
 754                 Z_Close_protocolError,
 755                 "double init");
 756
 757             package.session().close();
 758         }
 759         else if (apdu->which == Z_APDU_searchRequest)
 760         {
 761             f->search(package, apdu);
 762         }
 763         else if (apdu->which == Z_APDU_presentRequest)
 764         {
 765             f->present(package, apdu);
 766         }
 767         else if (apdu->which == Z_APDU_scanRequest)
 768         {
 769             f->scan(package, apdu);
 770         }
 771         else if (apdu->which == Z_APDU_close)
 772         {
 773             package.session().close();
 774         }
 775         else
 776         {
 777             mp::odr odr;
 778
 779             package.response() = odr.create_close(
 780                 apdu, Z_Close_protocolError,
 781                 "unsupported APDU in filter_virt_db");
 782
 783             package.session().close();
 784         }
 785     }
 786     m_p->release_frontend(package);
 787 }
 788
 789
 790 void mp::filter::VirtualDB::configure(const xmlNode * ptr, bool test_only)
 791 {
 792     for (ptr = ptr->children; ptr; ptr = ptr->next)
 793     {
 794         if (ptr->type != XML_ELEMENT_NODE)
 795             continue;
 796         if (!strcmp((const char *) ptr->name, "pass-vhosts"))
 797         {
 798             m_p->pass_vhosts = mp::xml::get_bool(ptr->children, false);
 799         }
 800         else if (!strcmp((const char *) ptr->name, "virtual"))
 801         {
 802             std::string database;
 803             std::list<std::string> targets;
 804             xmlNode *v_node = ptr->children;
 805             for (; v_node; v_node = v_node->next)
 806             {
 807                 if (v_node->type != XML_ELEMENT_NODE)
 808                     continue;
 809
 810                 if (mp::xml::is_element_mp(v_node, "database"))
 811                     database = mp::xml::get_text(v_node);
 812                 else if (mp::xml::is_element_mp(v_node, "target"))
 813                     targets.push_back(mp::xml::get_text(v_node));
 814                 else
 815                     throw mp::filter::FilterException
 816                         ("Bad element "
 817                          + std::string((const char *) v_node->name)
 818                          + " in virtual section"
 819                             );
 820             }
 821             std::string route = mp::xml::get_route(ptr);
 822             add_map_db2targets(database, targets, route);
 823         }
 824         else
 825         {
 826             throw mp::filter::FilterException
 827                 ("Bad element "
 828                  + std::string((const char *) ptr->name)
 829                  + " in virt_db filter");
 830         }
 831     }
 832 }
 833
 834 static mp::filter::Base* filter_creator()
 835 {
 836     return new mp::filter::VirtualDB;
 837 }
 838
 839 extern "C" {
 840     struct metaproxy_1_filter_struct metaproxy_1_filter_virt_db = {
 841         0,
 842         "virt_db",
 843         filter_creator
 844     };
 845 }
 846
 847
 848 /*
 849  * Local variables:
 850  * c-basic-offset: 4
 851  * c-file-style: "Stroustrup"
 852  * indent-tabs-mode: nil
 853  * End:
 854  * vim: shiftwidth=4 tabstop=8 expandtab
 855  */
 856