src/filter_multi.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 <yaz/log.h>
  20
  21 #include "config.hpp"
  22
  23 #include <metaproxy/filter.hpp>
  24 #include <metaproxy/package.hpp>
  25
  26 #include <boost/thread/thread.hpp>
  27 #include <boost/thread/mutex.hpp>
  28 #include <boost/thread/condition.hpp>
  29 #include <boost/shared_ptr.hpp>
  30
  31 #include <metaproxy/util.hpp>
  32 #include "filter_multi.hpp"
  33
  34 #include <yaz/zgdu.h>
  35 #include <yaz/otherinfo.h>
  36 #include <yaz/diagbib1.h>
  37 #include <yaz/match_glob.h>
  38
  39 #include <vector>
  40 #include <algorithm>
  41 #include <map>
  42 #include <iostream>
  43
  44 namespace mp = metaproxy_1;
  45 namespace yf = mp::filter;
  46
  47 namespace metaproxy_1 {
  48     namespace filter {
  49         enum multi_merge_type {
  50             round_robin,
  51             serve_order
  52         };
  53         struct Multi::BackendSet {
  54             BackendPtr m_backend;
  55             int m_count;
  56             bool operator < (const BackendSet &k) const;
  57             bool operator == (const BackendSet &k) const;
  58         };
  59         struct Multi::ScanTermInfo {
  60             std::string m_norm_term;
  61             std::string m_display_term;
  62             int m_count;
  63             bool operator < (const ScanTermInfo &) const;
  64             bool operator == (const ScanTermInfo &) const;
  65             Z_Entry *get_entry(ODR odr);
  66         };
  67         struct Multi::FrontendSet {
  68             class PresentJob {
  69             public:
  70                 BackendPtr m_backend;
  71                 int m_pos; // position for backend (1=first, 2=second,..
  72                 int m_start; // present request start
  73                 PresentJob(BackendPtr ptr, int pos) :
  74                     m_backend(ptr), m_pos(pos), m_start(0) {};
  75             };
  76             FrontendSet(std::string setname);
  77             FrontendSet();
  78             ~FrontendSet();
  79
  80             void round_robin(int pos, int number, std::list<PresentJob> &job);
  81             void serve_order(int pos, int number, std::list<PresentJob> &job);
  82
  83             std::list<BackendSet> m_backend_sets;
  84             std::string m_setname;
  85         };
  86         struct Multi::Backend {
  87             PackagePtr m_package;
  88             std::string m_backend_database;
  89             std::string m_vhost;
  90             std::string m_route;
  91             void operator() (void);  // thread operation
  92         };
  93         struct Multi::Frontend {
  94             Frontend(Rep *rep);
  95             ~Frontend();
  96             bool m_is_multi;
  97             bool m_in_use;
  98             std::list<BackendPtr> m_backend_list;
  99             std::map<std::string,Multi::FrontendSet> m_sets;
 100
 101             void multi_move(std::list<BackendPtr> &blist);
 102             void init(Package &package, Z_GDU *gdu);
 103             void close(Package &package);
 104             void search(Package &package, Z_APDU *apdu);
 105             void present(Package &package, Z_APDU *apdu);
 106             void scan1(Package &package, Z_APDU *apdu);
 107             void scan2(Package &package, Z_APDU *apdu);
 108             Rep *m_p;
 109         };
 110         class Multi::Map {
 111             std::string m_target_pattern;
 112             std::string m_route;
 113         public:
 114             Map(std::string pattern, std::string route) :
 115                 m_target_pattern(pattern), m_route(route) {};
 116             bool match(const std::string target, std::string *ret) const {
 117                 if (yaz_match_glob(m_target_pattern.c_str(), target.c_str()))
 118                 {
 119                     *ret = m_route;
 120                     return true;
 121                 }
 122                 return false;
 123             };
 124         };
 125         class Multi::Rep {
 126             friend class Multi;
 127             friend struct Frontend;
 128
 129             Rep();
 130             FrontendPtr get_frontend(Package &package);
 131             void release_frontend(Package &package);
 132         private:
 133             std::list<Multi::Map> m_route_patterns;
 134             boost::mutex m_mutex;
 135             boost::condition m_cond_session_ready;
 136             std::map<mp::Session, FrontendPtr> m_clients;
 137             bool m_hide_unavailable;
 138             multi_merge_type m_merge_type;
 139         };
 140     }
 141 }
 142
 143 yf::Multi::Rep::Rep()
 144 {
 145     m_hide_unavailable = false;
 146     m_merge_type = round_robin;
 147 }
 148
 149 bool yf::Multi::BackendSet::operator < (const BackendSet &k) const
 150 {
 151     return m_count < k.m_count;
 152 }
 153
 154 yf::Multi::Frontend::Frontend(Rep *rep)
 155 {
 156     m_p = rep;
 157     m_is_multi = false;
 158 }
 159
 160 yf::Multi::Frontend::~Frontend()
 161 {
 162 }
 163
 164 yf::Multi::FrontendPtr yf::Multi::Rep::get_frontend(mp::Package &package)
 165 {
 166     boost::mutex::scoped_lock lock(m_mutex);
 167
 168     std::map<mp::Session,yf::Multi::FrontendPtr>::iterator it;
 169
 170     while(true)
 171     {
 172         it = m_clients.find(package.session());
 173         if (it == m_clients.end())
 174             break;
 175
 176         if (!it->second->m_in_use)
 177         {
 178             it->second->m_in_use = true;
 179             return it->second;
 180         }
 181         m_cond_session_ready.wait(lock);
 182     }
 183     FrontendPtr f(new Frontend(this));
 184     m_clients[package.session()] = f;
 185     f->m_in_use = true;
 186     return f;
 187 }
 188
 189 void yf::Multi::Rep::release_frontend(mp::Package &package)
 190 {
 191     boost::mutex::scoped_lock lock(m_mutex);
 192     std::map<mp::Session,yf::Multi::FrontendPtr>::iterator it;
 193
 194     it = m_clients.find(package.session());
 195     if (it != m_clients.end())
 196     {
 197         if (package.session().is_closed())
 198         {
 199             it->second->close(package);
 200             m_clients.erase(it);
 201         }
 202         else
 203         {
 204             it->second->m_in_use = false;
 205         }
 206         m_cond_session_ready.notify_all();
 207     }
 208 }
 209
 210 yf::Multi::FrontendSet::FrontendSet(std::string setname)
 211     :  m_setname(setname)
 212 {
 213 }
 214
 215
 216 yf::Multi::FrontendSet::FrontendSet()
 217 {
 218 }
 219
 220
 221 yf::Multi::FrontendSet::~FrontendSet()
 222 {
 223 }
 224
 225 yf::Multi::Multi() : m_p(new Multi::Rep)
 226 {
 227 }
 228
 229 yf::Multi::~Multi() {
 230 }
 231
 232
 233 void yf::Multi::Backend::operator() (void)
 234 {
 235     m_package->move(m_route);
 236 }
 237
 238
 239 void yf::Multi::Frontend::close(mp::Package &package)
 240 {
 241     std::list<BackendPtr>::const_iterator bit;
 242     for (bit = m_backend_list.begin(); bit != m_backend_list.end(); bit++)
 243     {
 244         BackendPtr b = *bit;
 245
 246         b->m_package->copy_filter(package);
 247         b->m_package->request() = (Z_GDU *) 0;
 248         b->m_package->session().close();
 249         b->m_package->move(b->m_route);
 250     }
 251 }
 252
 253 void yf::Multi::Frontend::multi_move(std::list<BackendPtr> &blist)
 254 {
 255     std::list<BackendPtr>::const_iterator bit;
 256     boost::thread_group g;
 257     for (bit = blist.begin(); bit != blist.end(); bit++)
 258     {
 259         g.add_thread(new boost::thread(**bit));
 260     }
 261     g.join_all();
 262 }
 263
 264 void yf::Multi::FrontendSet::serve_order(int start, int number,
 265                                          std::list<PresentJob> &jobs)
 266 {
 267     int i;
 268     for (i = 0; i < number; i++)
 269     {
 270         std::list<BackendSet>::const_iterator bsit;
 271         int voffset = 0;
 272         int offset = start + i - 1;
 273         for (bsit = m_backend_sets.begin(); bsit != m_backend_sets.end();
 274              bsit++)
 275         {
 276             if (offset >= voffset && offset < voffset + bsit->m_count)
 277             {
 278                 PresentJob job(bsit->m_backend, offset - voffset + 1);
 279                 jobs.push_back(job);
 280                 break;
 281             }
 282             voffset += bsit->m_count;
 283         }
 284     }
 285 }
 286
 287 void yf::Multi::FrontendSet::round_robin(int start, int number,
 288                                          std::list<PresentJob> &jobs)
 289 {
 290     std::list<int> pos;
 291     std::list<BackendSet>::const_iterator bsit;
 292     for (bsit = m_backend_sets.begin(); bsit != m_backend_sets.end(); bsit++)
 293     {
 294         pos.push_back(1);
 295     }
 296
 297     int p = 1;
 298 #if 1
 299     // optimization step!
 300     int omin = 0;
 301     while(true)
 302     {
 303         int min = 0;
 304         int no_left = 0;
 305         // find min count for each set which is > omin
 306         for (bsit = m_backend_sets.begin(); bsit != m_backend_sets.end(); bsit++)
 307         {
 308             if (bsit->m_count > omin)
 309             {
 310                 if (no_left == 0 || bsit->m_count < min)
 311                     min = bsit->m_count;
 312                 no_left++;
 313             }
 314         }
 315         if (no_left == 0) // if nothing greater than omin, bail out.
 316             break;
 317         int skip = no_left * min;
 318         if (p + skip > start)  // step gets us "into" present range?
 319         {
 320             // Yes. skip until start.. Rounding off is deliberate!
 321             min = (start-p) / no_left;
 322             p += no_left * min;
 323
 324             // update positions in each set..
 325             std::list<int>::iterator psit = pos.begin();
 326             for (psit = pos.begin(); psit != pos.end(); psit++)
 327                 *psit += min;
 328             break;
 329         }
 330         // skip on each set.. before "present range"..
 331         p = p + skip;
 332
 333         std::list<int>::iterator psit = pos.begin();
 334         for (psit = pos.begin(); psit != pos.end(); psit++)
 335             *psit += min;
 336
 337         omin = min; // update so we consider next class (with higher count)
 338     }
 339 #endif
 340     int fetched = 0;
 341     bool more = true;
 342     while (more)
 343     {
 344         more = false;
 345         std::list<int>::iterator psit = pos.begin();
 346         bsit = m_backend_sets.begin();
 347
 348         for (; bsit != m_backend_sets.end(); psit++,bsit++)
 349         {
 350             if (fetched >= number)
 351             {
 352                 more = false;
 353                 break;
 354             }
 355             if (*psit <= bsit->m_count)
 356             {
 357                 if (p >= start)
 358                 {
 359                     PresentJob job(bsit->m_backend, *psit);
 360                     jobs.push_back(job);
 361                     fetched++;
 362                 }
 363                 (*psit)++;
 364                 p++;
 365                 more = true;
 366             }
 367         }
 368     }
 369 }
 370
 371 void yf::Multi::Frontend::init(mp::Package &package, Z_GDU *gdu)
 372 {
 373     Z_InitRequest *req = gdu->u.z3950->u.initRequest;
 374
 375     std::list<std::string> targets;
 376
 377     mp::util::get_vhost_otherinfo(req->otherInfo, targets);
 378
 379     if (targets.size() < 1)
 380     {
 381         package.move();
 382         return;
 383     }
 384
 385     std::list<std::string>::const_iterator t_it = targets.begin();
 386     for (; t_it != targets.end(); t_it++)
 387     {
 388         Session s;
 389         Backend *b = new Backend;
 390         b->m_vhost = *t_it;
 391
 392         std::list<Multi::Map>::const_iterator it =
 393             m_p->m_route_patterns.begin();
 394         while (it != m_p->m_route_patterns.end()) {
 395             if (it->match(*t_it, &b->m_route))
 396                 break;
 397             it++;
 398         }
 399         // b->m_route = m_p->m_target_route[*t_it];
 400         // b->m_route unset
 401         b->m_package = PackagePtr(new Package(s, package.origin()));
 402
 403         m_backend_list.push_back(BackendPtr(b));
 404     }
 405     m_is_multi = true;
 406
 407     // create init request
 408     std::list<BackendPtr>::iterator bit;
 409     for (bit = m_backend_list.begin(); bit != m_backend_list.end(); bit++)
 410     {
 411         mp::odr odr;
 412         BackendPtr b = *bit;
 413         Z_APDU *init_apdu = zget_APDU(odr, Z_APDU_initRequest);
 414
 415         std::list<std::string>vhost_one;
 416         vhost_one.push_back(b->m_vhost);
 417         mp::util::set_vhost_otherinfo(&init_apdu->u.initRequest->otherInfo,
 418                                        odr, vhost_one);
 419
 420
 421         Z_InitRequest *breq = init_apdu->u.initRequest;
 422
 423         breq->idAuthentication = req->idAuthentication;
 424
 425         ODR_MASK_SET(breq->options, Z_Options_search);
 426         ODR_MASK_SET(breq->options, Z_Options_present);
 427         ODR_MASK_SET(breq->options, Z_Options_namedResultSets);
 428         ODR_MASK_SET(breq->options, Z_Options_scan);
 429
 430         ODR_MASK_SET(breq->protocolVersion, Z_ProtocolVersion_1);
 431         ODR_MASK_SET(breq->protocolVersion, Z_ProtocolVersion_2);
 432         ODR_MASK_SET(breq->protocolVersion, Z_ProtocolVersion_3);
 433
 434         b->m_package->request() = init_apdu;
 435
 436         b->m_package->copy_filter(package);
 437     }
 438     multi_move(m_backend_list);
 439
 440     // create the frontend init response based on each backend init response
 441     mp::odr odr;
 442
 443     Z_APDU *f_apdu = odr.create_initResponse(gdu->u.z3950, 0, 0);
 444     Z_InitResponse *f_resp = f_apdu->u.initResponse;
 445
 446     ODR_MASK_SET(f_resp->options, Z_Options_search);
 447     ODR_MASK_SET(f_resp->options, Z_Options_present);
 448     ODR_MASK_SET(f_resp->options, Z_Options_namedResultSets);
 449     ODR_MASK_SET(f_resp->options, Z_Options_scan);
 450
 451     ODR_MASK_SET(f_resp->protocolVersion, Z_ProtocolVersion_1);
 452     ODR_MASK_SET(f_resp->protocolVersion, Z_ProtocolVersion_2);
 453     ODR_MASK_SET(f_resp->protocolVersion, Z_ProtocolVersion_3);
 454
 455     int no_failed = 0;
 456     int no_succeeded = 0;
 457     for (bit = m_backend_list.begin(); bit != m_backend_list.end(); )
 458     {
 459         PackagePtr p = (*bit)->m_package;
 460
 461         if (p->session().is_closed())
 462         {
 463             // failed. Remove from list and increment number of failed
 464             no_failed++;
 465             bit = m_backend_list.erase(bit);
 466             continue;
 467         }
 468         Z_GDU *gdu = p->response().get();
 469         if (gdu && gdu->which == Z_GDU_Z3950 && gdu->u.z3950->which ==
 470             Z_APDU_initResponse)
 471         {
 472             int i;
 473             Z_APDU *b_apdu = gdu->u.z3950;
 474             Z_InitResponse *b_resp = b_apdu->u.initResponse;
 475
 476             // common options for all backends
 477             for (i = 0; i <= Z_Options_stringSchema; i++)
 478             {
 479                 if (!ODR_MASK_GET(b_resp->options, i))
 480                     ODR_MASK_CLEAR(f_resp->options, i);
 481             }
 482             // common protocol version
 483             for (i = 0; i <= Z_ProtocolVersion_3; i++)
 484                 if (!ODR_MASK_GET(b_resp->protocolVersion, i))
 485                     ODR_MASK_CLEAR(f_resp->protocolVersion, i);
 486             if (*b_resp->result)
 487                 no_succeeded++;
 488             else
 489                 no_failed++;
 490         }
 491         else
 492             no_failed++;
 493         bit++;
 494     }
 495     if (m_p->m_hide_unavailable)
 496     {
 497         if (no_succeeded == 0)
 498         {
 499             *f_resp->result = 0;
 500             package.session().close();
 501         }
 502     }
 503     else
 504     {
 505         if (no_failed)
 506         {
 507             *f_resp->result = 0;
 508             package.session().close();
 509         }
 510     }
 511     package.response() = f_apdu;
 512 }
 513
 514 void yf::Multi::Frontend::search(mp::Package &package, Z_APDU *apdu_req)
 515 {
 516     // create search request
 517     Z_SearchRequest *req = apdu_req->u.searchRequest;
 518
 519     // save these for later
 520     int smallSetUpperBound = *req->smallSetUpperBound;
 521     int largeSetLowerBound = *req->largeSetLowerBound;
 522     int mediumSetPresentNumber = *req->mediumSetPresentNumber;
 523
 524     // they are altered now - to disable piggyback
 525     *req->smallSetUpperBound = 0;
 526     *req->largeSetLowerBound = 1;
 527     *req->mediumSetPresentNumber = 1;
 528
 529     int default_num_db = req->num_databaseNames;
 530     char **default_db = req->databaseNames;
 531
 532     std::list<BackendPtr>::const_iterator bit;
 533     for (bit = m_backend_list.begin(); bit != m_backend_list.end(); bit++)
 534     {
 535         PackagePtr p = (*bit)->m_package;
 536         mp::odr odr;
 537
 538         if (!mp::util::set_databases_from_zurl(odr, (*bit)->m_vhost,
 539                                                 &req->num_databaseNames,
 540                                                 &req->databaseNames))
 541         {
 542             req->num_databaseNames = default_num_db;
 543             req->databaseNames = default_db;
 544         }
 545         p->request() = apdu_req;
 546         p->copy_filter(package);
 547     }
 548     multi_move(m_backend_list);
 549
 550     // look at each response
 551     FrontendSet resultSet(std::string(req->resultSetName));
 552
 553     int result_set_size = 0;
 554     Z_Records *z_records_diag = 0;  // no diagnostics (yet)
 555     for (bit = m_backend_list.begin(); bit != m_backend_list.end(); bit++)
 556     {
 557         PackagePtr p = (*bit)->m_package;
 558
 559         if (p->session().is_closed()) // if any backend closes, close frontend
 560             package.session().close();
 561
 562         Z_GDU *gdu = p->response().get();
 563         if (gdu && gdu->which == Z_GDU_Z3950 && gdu->u.z3950->which ==
 564             Z_APDU_searchResponse)
 565         {
 566             Z_APDU *b_apdu = gdu->u.z3950;
 567             Z_SearchResponse *b_resp = b_apdu->u.searchResponse;
 568
 569             // see we get any errors (AKA diagnstics)
 570             if (b_resp->records)
 571             {
 572                 if (b_resp->records->which == Z_Records_NSD
 573                     || b_resp->records->which == Z_Records_multipleNSD)
 574                     z_records_diag = b_resp->records;
 575                 // we may set this multiple times (TOO BAD!)
 576             }
 577             BackendSet backendSet;
 578             backendSet.m_backend = *bit;
 579             backendSet.m_count = *b_resp->resultCount;
 580             result_set_size += *b_resp->resultCount;
 581             resultSet.m_backend_sets.push_back(backendSet);
 582         }
 583         else
 584         {
 585             // if any target does not return search response - return that
 586             package.response() = p->response();
 587             return;
 588         }
 589     }
 590
 591     mp::odr odr;
 592     Z_APDU *f_apdu = odr.create_searchResponse(apdu_req, 0, 0);
 593     Z_SearchResponse *f_resp = f_apdu->u.searchResponse;
 594
 595     *f_resp->resultCount = result_set_size;
 596     if (z_records_diag)
 597     {
 598         // search error
 599         f_resp->records = z_records_diag;
 600         package.response() = f_apdu;
 601         return;
 602     }
 603     // assume OK
 604     m_sets[resultSet.m_setname] = resultSet;
 605
 606     int number;
 607     mp::util::piggyback(smallSetUpperBound,
 608                          largeSetLowerBound,
 609                          mediumSetPresentNumber,
 610                          result_set_size,
 611                          number);
 612     Package pp(package.session(), package.origin());
 613     if (number > 0)
 614     {
 615         pp.copy_filter(package);
 616         Z_APDU *p_apdu = zget_APDU(odr, Z_APDU_presentRequest);
 617         Z_PresentRequest *p_req = p_apdu->u.presentRequest;
 618         p_req->preferredRecordSyntax = req->preferredRecordSyntax;
 619         p_req->resultSetId = req->resultSetName;
 620         *p_req->resultSetStartPoint = 1;
 621         *p_req->numberOfRecordsRequested = number;
 622         pp.request() = p_apdu;
 623         present(pp, p_apdu);
 624
 625         if (pp.session().is_closed())
 626             package.session().close();
 627
 628         Z_GDU *gdu = pp.response().get();
 629         if (gdu && gdu->which == Z_GDU_Z3950 && gdu->u.z3950->which ==
 630             Z_APDU_presentResponse)
 631         {
 632             Z_PresentResponse *p_res = gdu->u.z3950->u.presentResponse;
 633             f_resp->records = p_res->records;
 634             *f_resp->numberOfRecordsReturned =
 635                 *p_res->numberOfRecordsReturned;
 636             *f_resp->nextResultSetPosition =
 637                 *p_res->nextResultSetPosition;
 638         }
 639         else
 640         {
 641             package.response() = pp.response();
 642             return;
 643         }
 644     }
 645     package.response() = f_apdu; // in this scope because of p
 646 }
 647
 648 void yf::Multi::Frontend::present(mp::Package &package, Z_APDU *apdu_req)
 649 {
 650     // create present request
 651     Z_PresentRequest *req = apdu_req->u.presentRequest;
 652
 653     Sets_it it;
 654     it = m_sets.find(std::string(req->resultSetId));
 655     if (it == m_sets.end())
 656     {
 657         mp::odr odr;
 658         Z_APDU *apdu =
 659             odr.create_presentResponse(
 660                 apdu_req,
 661                 YAZ_BIB1_SPECIFIED_RESULT_SET_DOES_NOT_EXIST,
 662                 req->resultSetId);
 663         package.response() = apdu;
 664         return;
 665     }
 666     std::list<Multi::FrontendSet::PresentJob> jobs;
 667     int start = *req->resultSetStartPoint;
 668     int number = *req->numberOfRecordsRequested;
 669
 670     if (m_p->m_merge_type == round_robin)
 671         it->second.round_robin(start, number, jobs);
 672     else if (m_p->m_merge_type == serve_order)
 673         it->second.serve_order(start, number, jobs);
 674
 675     if (0)
 676     {
 677         std::list<Multi::FrontendSet::PresentJob>::const_iterator jit;
 678         for (jit = jobs.begin(); jit != jobs.end(); jit++)
 679         {
 680             yaz_log(YLOG_LOG, "job pos=%d", jit->m_pos);
 681         }
 682     }
 683
 684     std::list<BackendPtr> present_backend_list;
 685
 686     std::list<BackendSet>::const_iterator bsit;
 687     bsit = it->second.m_backend_sets.begin();
 688     for (; bsit != it->second.m_backend_sets.end(); bsit++)
 689     {
 690         int start = -1;
 691         int end = -1;
 692         {
 693             std::list<Multi::FrontendSet::PresentJob>::const_iterator jit;
 694             for (jit = jobs.begin(); jit != jobs.end(); jit++)
 695             {
 696                 if (jit->m_backend == bsit->m_backend)
 697                 {
 698                     if (start == -1 || jit->m_pos < start)
 699                         start = jit->m_pos;
 700                     if (end == -1 || jit->m_pos > end)
 701                         end = jit->m_pos;
 702                 }
 703             }
 704         }
 705         if (start != -1)
 706         {
 707             std::list<Multi::FrontendSet::PresentJob>::iterator jit;
 708             for (jit = jobs.begin(); jit != jobs.end(); jit++)
 709             {
 710                 if (jit->m_backend == bsit->m_backend)
 711                 {
 712                     if (jit->m_pos >= start && jit->m_pos <= end)
 713                         jit->m_start = start;
 714                 }
 715             }
 716
 717             PackagePtr p = bsit->m_backend->m_package;
 718
 719             *req->resultSetStartPoint = start;
 720             *req->numberOfRecordsRequested = end - start + 1;
 721
 722             p->request() = apdu_req;
 723             p->copy_filter(package);
 724
 725             present_backend_list.push_back(bsit->m_backend);
 726         }
 727     }
 728     multi_move(present_backend_list);
 729
 730     // look at each response
 731     Z_Records *z_records_diag = 0;
 732
 733     std::list<BackendPtr>::const_iterator pbit = present_backend_list.begin();
 734     for (; pbit != present_backend_list.end(); pbit++)
 735     {
 736         PackagePtr p = (*pbit)->m_package;
 737
 738         if (p->session().is_closed()) // if any backend closes, close frontend
 739             package.session().close();
 740
 741         Z_GDU *gdu = p->response().get();
 742         if (gdu && gdu->which == Z_GDU_Z3950 && gdu->u.z3950->which ==
 743             Z_APDU_presentResponse)
 744         {
 745             Z_APDU *b_apdu = gdu->u.z3950;
 746             Z_PresentResponse *b_resp = b_apdu->u.presentResponse;
 747
 748             // see we get any errors (AKA diagnstics)
 749             if (b_resp->records)
 750             {
 751                 if (b_resp->records->which != Z_Records_DBOSD)
 752                     z_records_diag = b_resp->records;
 753                 // we may set this multiple times (TOO BAD!)
 754             }
 755         }
 756         else
 757         {
 758             // if any target does not return present response - return that
 759             package.response() = p->response();
 760             return;
 761         }
 762     }
 763
 764     mp::odr odr;
 765     Z_APDU *f_apdu = odr.create_presentResponse(apdu_req, 0, 0);
 766     Z_PresentResponse *f_resp = f_apdu->u.presentResponse;
 767
 768     if (z_records_diag)
 769     {
 770         f_resp->records = z_records_diag;
 771         *f_resp->presentStatus = Z_PresentStatus_failure;
 772     }
 773     else if (number < 0 || (size_t) number > jobs.size())
 774     {
 775         f_apdu =
 776             odr.create_presentResponse(
 777                 apdu_req,
 778                 YAZ_BIB1_PRESENT_REQUEST_OUT_OF_RANGE,
 779                 0);
 780     }
 781     else
 782     {
 783         f_resp->records = (Z_Records *) odr_malloc(odr, sizeof(Z_Records));
 784         Z_Records * records = f_resp->records;
 785         records->which = Z_Records_DBOSD;
 786         records->u.databaseOrSurDiagnostics =
 787             (Z_NamePlusRecordList *)
 788             odr_malloc(odr, sizeof(Z_NamePlusRecordList));
 789         Z_NamePlusRecordList *nprl = records->u.databaseOrSurDiagnostics;
 790         nprl->num_records = jobs.size();
 791         nprl->records = (Z_NamePlusRecord**)
 792             odr_malloc(odr, sizeof(Z_NamePlusRecord *) * nprl->num_records);
 793         int i = 0;
 794         std::list<Multi::FrontendSet::PresentJob>::const_iterator jit;
 795         for (jit = jobs.begin(); jit != jobs.end(); jit++, i++)
 796         {
 797             PackagePtr p = jit->m_backend->m_package;
 798
 799             Z_GDU *gdu = p->response().get();
 800             Z_APDU *b_apdu = gdu->u.z3950;
 801             Z_PresentResponse *b_resp = b_apdu->u.presentResponse;
 802
 803             nprl->records[i] = (Z_NamePlusRecord*)
 804                 odr_malloc(odr, sizeof(Z_NamePlusRecord));
 805             int inside_pos = jit->m_pos - jit->m_start;
 806             if (inside_pos >= b_resp->records->
 807                 u.databaseOrSurDiagnostics->num_records)
 808                 break;
 809             *nprl->records[i] = *b_resp->records->
 810                 u.databaseOrSurDiagnostics->records[inside_pos];
 811             nprl->records[i]->databaseName =
 812                     odr_strdup(odr, jit->m_backend->m_vhost.c_str());
 813         }
 814         nprl->num_records = i; // usually same as jobs.size();
 815         *f_resp->nextResultSetPosition = start + i;
 816         *f_resp->numberOfRecordsReturned = i;
 817     }
 818     package.response() = f_apdu;
 819 }
 820
 821 void yf::Multi::Frontend::scan1(mp::Package &package, Z_APDU *apdu_req)
 822 {
 823     if (m_backend_list.size() > 1)
 824     {
 825         mp::odr odr;
 826         Z_APDU *f_apdu =
 827             odr.create_scanResponse(
 828                 apdu_req, YAZ_BIB1_COMBI_OF_SPECIFIED_DATABASES_UNSUPP, 0);
 829         package.response() = f_apdu;
 830         return;
 831     }
 832     Z_ScanRequest *req = apdu_req->u.scanRequest;
 833
 834     int default_num_db = req->num_databaseNames;
 835     char **default_db = req->databaseNames;
 836
 837     std::list<BackendPtr>::const_iterator bit;
 838     for (bit = m_backend_list.begin(); bit != m_backend_list.end(); bit++)
 839     {
 840         PackagePtr p = (*bit)->m_package;
 841         mp::odr odr;
 842
 843         if (!mp::util::set_databases_from_zurl(odr, (*bit)->m_vhost,
 844                                                 &req->num_databaseNames,
 845                                                 &req->databaseNames))
 846         {
 847             req->num_databaseNames = default_num_db;
 848             req->databaseNames = default_db;
 849         }
 850         p->request() = apdu_req;
 851         p->copy_filter(package);
 852     }
 853     multi_move(m_backend_list);
 854
 855     for (bit = m_backend_list.begin(); bit != m_backend_list.end(); bit++)
 856     {
 857         PackagePtr p = (*bit)->m_package;
 858
 859         if (p->session().is_closed()) // if any backend closes, close frontend
 860             package.session().close();
 861
 862         Z_GDU *gdu = p->response().get();
 863         if (gdu && gdu->which == Z_GDU_Z3950 && gdu->u.z3950->which ==
 864             Z_APDU_scanResponse)
 865         {
 866             package.response() = p->response();
 867             break;
 868         }
 869         else
 870         {
 871             // if any target does not return scan response - return that
 872             package.response() = p->response();
 873             return;
 874         }
 875     }
 876 }
 877
 878 bool yf::Multi::ScanTermInfo::operator < (const ScanTermInfo &k) const
 879 {
 880     return m_norm_term < k.m_norm_term;
 881 }
 882
 883 bool yf::Multi::ScanTermInfo::operator == (const ScanTermInfo &k) const
 884 {
 885     return m_norm_term == k.m_norm_term;
 886 }
 887
 888 Z_Entry *yf::Multi::ScanTermInfo::get_entry(ODR odr)
 889 {
 890     Z_Entry *e = (Z_Entry *)odr_malloc(odr, sizeof(*e));
 891     e->which = Z_Entry_termInfo;
 892     Z_TermInfo *t;
 893     t = e->u.termInfo = (Z_TermInfo *) odr_malloc(odr, sizeof(*t));
 894     t->suggestedAttributes = 0;
 895     t->displayTerm = 0;
 896     t->alternativeTerm = 0;
 897     t->byAttributes = 0;
 898     t->otherTermInfo = 0;
 899     t->globalOccurrences = odr_intdup(odr, m_count);
 900     t->term = (Z_Term *)
 901         odr_malloc(odr, sizeof(*t->term));
 902     t->term->which = Z_Term_general;
 903     Odr_oct *o;
 904     t->term->u.general = o = (Odr_oct *)odr_malloc(odr, sizeof(Odr_oct));
 905
 906     o->len = o->size = m_norm_term.size();
 907     o->buf = (unsigned char *) odr_malloc(odr, o->len);
 908     memcpy(o->buf, m_norm_term.c_str(), o->len);
 909     return e;
 910 }
 911
 912 void yf::Multi::Frontend::scan2(mp::Package &package, Z_APDU *apdu_req)
 913 {
 914     Z_ScanRequest *req = apdu_req->u.scanRequest;
 915
 916     int default_num_db = req->num_databaseNames;
 917     char **default_db = req->databaseNames;
 918
 919     std::list<BackendPtr>::const_iterator bit;
 920     for (bit = m_backend_list.begin(); bit != m_backend_list.end(); bit++)
 921     {
 922         PackagePtr p = (*bit)->m_package;
 923         mp::odr odr;
 924
 925         if (!mp::util::set_databases_from_zurl(odr, (*bit)->m_vhost,
 926                                                 &req->num_databaseNames,
 927                                                 &req->databaseNames))
 928         {
 929             req->num_databaseNames = default_num_db;
 930             req->databaseNames = default_db;
 931         }
 932         p->request() = apdu_req;
 933         p->copy_filter(package);
 934     }
 935     multi_move(m_backend_list);
 936
 937     ScanTermInfoList entries_before;
 938     ScanTermInfoList entries_after;
 939     int no_before = 0;
 940     int no_after = 0;
 941
 942     for (bit = m_backend_list.begin(); bit != m_backend_list.end(); bit++)
 943     {
 944         PackagePtr p = (*bit)->m_package;
 945
 946         if (p->session().is_closed()) // if any backend closes, close frontend
 947             package.session().close();
 948
 949         Z_GDU *gdu = p->response().get();
 950         if (gdu && gdu->which == Z_GDU_Z3950 && gdu->u.z3950->which ==
 951             Z_APDU_scanResponse)
 952         {
 953             Z_ScanResponse *res = gdu->u.z3950->u.scanResponse;
 954
 955             if (res->entries && res->entries->nonsurrogateDiagnostics)
 956             {
 957                 // failure
 958                 mp::odr odr;
 959                 Z_APDU *f_apdu = odr.create_scanResponse(apdu_req, 1, 0);
 960                 Z_ScanResponse *f_res = f_apdu->u.scanResponse;
 961
 962                 f_res->entries->nonsurrogateDiagnostics =
 963                     res->entries->nonsurrogateDiagnostics;
 964                 f_res->entries->num_nonsurrogateDiagnostics =
 965                     res->entries->num_nonsurrogateDiagnostics;
 966
 967                 package.response() = f_apdu;
 968                 return;
 969             }
 970
 971             if (res->entries && res->entries->entries)
 972             {
 973                 Z_Entry **entries = res->entries->entries;
 974                 int num_entries = res->entries->num_entries;
 975                 int position = 1;
 976                 if (req->preferredPositionInResponse)
 977                     position = *req->preferredPositionInResponse;
 978                 if (res->positionOfTerm)
 979                     position = *res->positionOfTerm;
 980
 981                 // before
 982                 int i;
 983                 for (i = 0; i<position-1 && i<num_entries; i++)
 984                 {
 985                     Z_Entry *ent = entries[i];
 986
 987                     if (ent->which == Z_Entry_termInfo)
 988                     {
 989                         ScanTermInfo my;
 990
 991                         Odr_int *occur = ent->u.termInfo->globalOccurrences;
 992                         my.m_count = occur ? *occur : 0;
 993
 994                         if (ent->u.termInfo->term->which == Z_Term_general)
 995                         {
 996                             my.m_norm_term = std::string(
 997                                 (const char *)
 998                                 ent->u.termInfo->term->u.general->buf,
 999                                 ent->u.termInfo->term->u.general->len);
1000                         }
1001                         if (my.m_norm_term.length())
1002                         {
1003                             ScanTermInfoList::iterator it =
1004                                 entries_before.begin();
1005                             while (it != entries_before.end() && my <*it)
1006                                 it++;
1007                             if (my == *it)
1008                             {
1009                                 it->m_count += my.m_count;
1010                             }
1011                             else
1012                             {
1013                                 entries_before.insert(it, my);
1014                                 no_before++;
1015                             }
1016                         }
1017                     }
1018                 }
1019                 // after
1020                 if (position <= 0)
1021                     i = 0;
1022                 else
1023                     i = position-1;
1024                 for ( ; i<num_entries; i++)
1025                 {
1026                     Z_Entry *ent = entries[i];
1027
1028                     if (ent->which == Z_Entry_termInfo)
1029                     {
1030                         ScanTermInfo my;
1031
1032                         Odr_int *occur = ent->u.termInfo->globalOccurrences;
1033                         my.m_count = occur ? *occur : 0;
1034
1035                         if (ent->u.termInfo->term->which == Z_Term_general)
1036                         {
1037                             my.m_norm_term = std::string(
1038                                 (const char *)
1039                                 ent->u.termInfo->term->u.general->buf,
1040                                 ent->u.termInfo->term->u.general->len);
1041                         }
1042                         if (my.m_norm_term.length())
1043                         {
1044                             ScanTermInfoList::iterator it =
1045                                 entries_after.begin();
1046                             while (it != entries_after.end() && *it < my)
1047                                 it++;
1048                             if (my == *it)
1049                             {
1050                                 it->m_count += my.m_count;
1051                             }
1052                             else
1053                             {
1054                                 entries_after.insert(it, my);
1055                                 no_after++;
1056                             }
1057                         }
1058                     }
1059                 }
1060
1061             }
1062         }
1063         else
1064         {
1065             // if any target does not return scan response - return that
1066             package.response() = p->response();
1067             return;
1068         }
1069     }
1070
1071     if (false)
1072     {
1073         std::cout << "BEFORE\n";
1074         ScanTermInfoList::iterator it = entries_before.begin();
1075         for(; it != entries_before.end(); it++)
1076         {
1077             std::cout << " " << it->m_norm_term << " " << it->m_count << "\n";
1078         }
1079
1080         std::cout << "AFTER\n";
1081         it = entries_after.begin();
1082         for(; it != entries_after.end(); it++)
1083         {
1084             std::cout << " " << it->m_norm_term << " " << it->m_count << "\n";
1085         }
1086     }
1087
1088     if (false)
1089     {
1090         mp::odr odr;
1091         Z_APDU *f_apdu = odr.create_scanResponse(apdu_req, 1, "not implemented");
1092         package.response() = f_apdu;
1093     }
1094     else
1095     {
1096         mp::odr odr;
1097         Z_APDU *f_apdu = odr.create_scanResponse(apdu_req, 0, 0);
1098         Z_ScanResponse *resp = f_apdu->u.scanResponse;
1099
1100         int number_returned = *req->numberOfTermsRequested;
1101         int position_returned = *req->preferredPositionInResponse;
1102
1103         resp->entries->num_entries = number_returned;
1104         resp->entries->entries = (Z_Entry**)
1105             odr_malloc(odr, sizeof(Z_Entry*) * number_returned);
1106         int i;
1107
1108         int lbefore = entries_before.size();
1109         if (lbefore < position_returned-1)
1110             position_returned = lbefore+1;
1111
1112         ScanTermInfoList::iterator it = entries_before.begin();
1113         for (i = 0; i<position_returned-1 && it != entries_before.end(); i++, it++)
1114         {
1115             resp->entries->entries[position_returned-2-i] = it->get_entry(odr);
1116         }
1117
1118         it = entries_after.begin();
1119
1120         if (position_returned <= 0)
1121             i = 0;
1122         else
1123             i = position_returned-1;
1124         for (; i<number_returned && it != entries_after.end(); i++, it++)
1125         {
1126             resp->entries->entries[i] = it->get_entry(odr);
1127         }
1128
1129         number_returned = i;
1130
1131         resp->positionOfTerm = odr_intdup(odr, position_returned);
1132         resp->numberOfEntriesReturned = odr_intdup(odr, number_returned);
1133         resp->entries->num_entries = number_returned;
1134
1135         package.response() = f_apdu;
1136     }
1137 }
1138
1139
1140 void yf::Multi::process(mp::Package &package) const
1141 {
1142     FrontendPtr f = m_p->get_frontend(package);
1143
1144     Z_GDU *gdu = package.request().get();
1145
1146     if (gdu && gdu->which == Z_GDU_Z3950 && gdu->u.z3950->which ==
1147         Z_APDU_initRequest && !f->m_is_multi)
1148     {
1149         f->init(package, gdu);
1150     }
1151     else if (!f->m_is_multi)
1152         package.move();
1153     else if (gdu && gdu->which == Z_GDU_Z3950)
1154     {
1155         Z_APDU *apdu = gdu->u.z3950;
1156         if (apdu->which == Z_APDU_initRequest)
1157         {
1158             mp::odr odr;
1159
1160             package.response() = odr.create_close(
1161                 apdu,
1162                 Z_Close_protocolError,
1163                 "double init");
1164
1165             package.session().close();
1166         }
1167         else if (apdu->which == Z_APDU_searchRequest)
1168         {
1169             f->search(package, apdu);
1170         }
1171         else if (apdu->which == Z_APDU_presentRequest)
1172         {
1173             f->present(package, apdu);
1174         }
1175         else if (apdu->which == Z_APDU_scanRequest)
1176         {
1177             f->scan2(package, apdu);
1178         }
1179         else
1180         {
1181             mp::odr odr;
1182
1183             package.response() = odr.create_close(
1184                 apdu, Z_Close_protocolError,
1185                 "unsupported APDU in filter multi");
1186
1187             package.session().close();
1188         }
1189     }
1190     m_p->release_frontend(package);
1191 }
1192
1193 void mp::filter::Multi::configure(const xmlNode * ptr, bool test_only)
1194 {
1195     for (ptr = ptr->children; ptr; ptr = ptr->next)
1196     {
1197         if (ptr->type != XML_ELEMENT_NODE)
1198             continue;
1199         if (!strcmp((const char *) ptr->name, "target"))
1200         {
1201             std::string route = mp::xml::get_route(ptr);
1202             std::string target = mp::xml::get_text(ptr);
1203             m_p->m_route_patterns.push_back(Multi::Map(target, route));
1204         }
1205         else if (!strcmp((const char *) ptr->name, "hideunavailable"))
1206         {
1207             m_p->m_hide_unavailable = true;
1208         }
1209         else if (!strcmp((const char *) ptr->name, "mergetype"))
1210         {
1211             std::string mergetype = mp::xml::get_text(ptr);
1212             if (mergetype == "roundrobin")
1213                 m_p->m_merge_type = round_robin;
1214             else if (mergetype == "serveorder")
1215                 m_p->m_merge_type = serve_order;
1216             else
1217                 throw mp::filter::FilterException
1218                     ("Bad mergetype "  + mergetype + " in multi filter");
1219
1220         }
1221         else
1222         {
1223             throw mp::filter::FilterException
1224                 ("Bad element "
1225                  + std::string((const char *) ptr->name)
1226                  + " in multi filter");
1227         }
1228     }
1229 }
1230
1231 static mp::filter::Base* filter_creator()
1232 {
1233     return new mp::filter::Multi;
1234 }
1235
1236 extern "C" {
1237     struct metaproxy_1_filter_struct metaproxy_1_filter_multi = {
1238         0,
1239         "multi",
1240         filter_creator
1241     };
1242 }
1243
1244
1245 /*
1246  * Local variables:
1247  * c-basic-offset: 4
1248  * c-file-style: "Stroustrup"
1249  * indent-tabs-mode: nil
1250  * End:
1251  * vim: shiftwidth=4 tabstop=8 expandtab
1252  */
1253