src/filter_multi.cpp

   1 /* This file is part of Metaproxy.
   2    Copyright (C) 2005-2009 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 "filter.hpp"
  24 #include "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 "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         Z_InitRequest *req = init_apdu->u.initRequest;
 421
 422         ODR_MASK_SET(req->options, Z_Options_search);
 423         ODR_MASK_SET(req->options, Z_Options_present);
 424         ODR_MASK_SET(req->options, Z_Options_namedResultSets);
 425         ODR_MASK_SET(req->options, Z_Options_scan);
 426
 427         ODR_MASK_SET(req->protocolVersion, Z_ProtocolVersion_1);
 428         ODR_MASK_SET(req->protocolVersion, Z_ProtocolVersion_2);
 429         ODR_MASK_SET(req->protocolVersion, Z_ProtocolVersion_3);
 430
 431         b->m_package->request() = init_apdu;
 432
 433         b->m_package->copy_filter(package);
 434     }
 435     multi_move(m_backend_list);
 436
 437     // create the frontend init response based on each backend init response
 438     mp::odr odr;
 439
 440     Z_APDU *f_apdu = odr.create_initResponse(gdu->u.z3950, 0, 0);
 441     Z_InitResponse *f_resp = f_apdu->u.initResponse;
 442
 443     ODR_MASK_SET(f_resp->options, Z_Options_search);
 444     ODR_MASK_SET(f_resp->options, Z_Options_present);
 445     ODR_MASK_SET(f_resp->options, Z_Options_namedResultSets);
 446
 447     ODR_MASK_SET(f_resp->protocolVersion, Z_ProtocolVersion_1);
 448     ODR_MASK_SET(f_resp->protocolVersion, Z_ProtocolVersion_2);
 449     ODR_MASK_SET(f_resp->protocolVersion, Z_ProtocolVersion_3);
 450
 451     int no_failed = 0;
 452     int no_succeeded = 0;
 453     for (bit = m_backend_list.begin(); bit != m_backend_list.end(); )
 454     {
 455         PackagePtr p = (*bit)->m_package;
 456
 457         if (p->session().is_closed())
 458         {
 459             // failed. Remove from list and increment number of failed
 460             no_failed++;
 461             bit = m_backend_list.erase(bit);
 462             continue;
 463         }
 464         no_succeeded++;
 465
 466         Z_GDU *gdu = p->response().get();
 467         if (gdu && gdu->which == Z_GDU_Z3950 && gdu->u.z3950->which ==
 468             Z_APDU_initResponse)
 469         {
 470             int i;
 471             Z_APDU *b_apdu = gdu->u.z3950;
 472             Z_InitResponse *b_resp = b_apdu->u.initResponse;
 473
 474             // common options for all backends
 475             for (i = 0; i <= Z_Options_stringSchema; i++)
 476             {
 477                 if (!ODR_MASK_GET(b_resp->options, i))
 478                     ODR_MASK_CLEAR(f_resp->options, i);
 479             }
 480             // common protocol version
 481             for (i = 0; i <= Z_ProtocolVersion_3; i++)
 482                 if (!ODR_MASK_GET(b_resp->protocolVersion, i))
 483                     ODR_MASK_CLEAR(f_resp->protocolVersion, i);
 484             // reject if any of the backends reject
 485             if (!*b_resp->result)
 486                 *f_resp->result = 0;
 487         }
 488         else
 489         {
 490             // if any target does not return init return that (close or
 491             // similar )
 492             package.response() = p->response();
 493             return;
 494         }
 495         bit++;
 496     }
 497     if (m_p->m_hide_unavailable)
 498     {
 499         if (no_succeeded == 0)
 500             package.session().close();
 501     }
 502     else
 503     {
 504         if (no_failed)
 505             package.session().close();
 506     }
 507     package.response() = f_apdu;
 508 }
 509
 510 void yf::Multi::Frontend::search(mp::Package &package, Z_APDU *apdu_req)
 511 {
 512     // create search request
 513     Z_SearchRequest *req = apdu_req->u.searchRequest;
 514
 515     // save these for later
 516     int smallSetUpperBound = *req->smallSetUpperBound;
 517     int largeSetLowerBound = *req->largeSetLowerBound;
 518     int mediumSetPresentNumber = *req->mediumSetPresentNumber;
 519
 520     // they are altered now - to disable piggyback
 521     *req->smallSetUpperBound = 0;
 522     *req->largeSetLowerBound = 1;
 523     *req->mediumSetPresentNumber = 1;
 524
 525     int default_num_db = req->num_databaseNames;
 526     char **default_db = req->databaseNames;
 527
 528     std::list<BackendPtr>::const_iterator bit;
 529     for (bit = m_backend_list.begin(); bit != m_backend_list.end(); bit++)
 530     {
 531         PackagePtr p = (*bit)->m_package;
 532         mp::odr odr;
 533
 534         if (!mp::util::set_databases_from_zurl(odr, (*bit)->m_vhost,
 535                                                 &req->num_databaseNames,
 536                                                 &req->databaseNames))
 537         {
 538             req->num_databaseNames = default_num_db;
 539             req->databaseNames = default_db;
 540         }
 541         p->request() = apdu_req;
 542         p->copy_filter(package);
 543     }
 544     multi_move(m_backend_list);
 545
 546     // look at each response
 547     FrontendSet resultSet(std::string(req->resultSetName));
 548
 549     int result_set_size = 0;
 550     Z_Records *z_records_diag = 0;  // no diagnostics (yet)
 551     for (bit = m_backend_list.begin(); bit != m_backend_list.end(); bit++)
 552     {
 553         PackagePtr p = (*bit)->m_package;
 554
 555         if (p->session().is_closed()) // if any backend closes, close frontend
 556             package.session().close();
 557
 558         Z_GDU *gdu = p->response().get();
 559         if (gdu && gdu->which == Z_GDU_Z3950 && gdu->u.z3950->which ==
 560             Z_APDU_searchResponse)
 561         {
 562             Z_APDU *b_apdu = gdu->u.z3950;
 563             Z_SearchResponse *b_resp = b_apdu->u.searchResponse;
 564
 565             // see we get any errors (AKA diagnstics)
 566             if (b_resp->records)
 567             {
 568                 if (b_resp->records->which == Z_Records_NSD
 569                     || b_resp->records->which == Z_Records_multipleNSD)
 570                     z_records_diag = b_resp->records;
 571                 // we may set this multiple times (TOO BAD!)
 572             }
 573             BackendSet backendSet;
 574             backendSet.m_backend = *bit;
 575             backendSet.m_count = *b_resp->resultCount;
 576             result_set_size += *b_resp->resultCount;
 577             resultSet.m_backend_sets.push_back(backendSet);
 578         }
 579         else
 580         {
 581             // if any target does not return search response - return that
 582             package.response() = p->response();
 583             return;
 584         }
 585     }
 586
 587     mp::odr odr;
 588     Z_APDU *f_apdu = odr.create_searchResponse(apdu_req, 0, 0);
 589     Z_SearchResponse *f_resp = f_apdu->u.searchResponse;
 590
 591     *f_resp->resultCount = result_set_size;
 592     if (z_records_diag)
 593     {
 594         // search error
 595         f_resp->records = z_records_diag;
 596         package.response() = f_apdu;
 597         return;
 598     }
 599     // assume OK
 600     m_sets[resultSet.m_setname] = resultSet;
 601
 602     int number;
 603     mp::util::piggyback(smallSetUpperBound,
 604                          largeSetLowerBound,
 605                          mediumSetPresentNumber,
 606                          result_set_size,
 607                          number);
 608     Package pp(package.session(), package.origin());
 609     if (number > 0)
 610     {
 611         pp.copy_filter(package);
 612         Z_APDU *p_apdu = zget_APDU(odr, Z_APDU_presentRequest);
 613         Z_PresentRequest *p_req = p_apdu->u.presentRequest;
 614         p_req->preferredRecordSyntax = req->preferredRecordSyntax;
 615         p_req->resultSetId = req->resultSetName;
 616         *p_req->resultSetStartPoint = 1;
 617         *p_req->numberOfRecordsRequested = number;
 618         pp.request() = p_apdu;
 619         present(pp, p_apdu);
 620
 621         if (pp.session().is_closed())
 622             package.session().close();
 623
 624         Z_GDU *gdu = pp.response().get();
 625         if (gdu && gdu->which == Z_GDU_Z3950 && gdu->u.z3950->which ==
 626             Z_APDU_presentResponse)
 627         {
 628             Z_PresentResponse *p_res = gdu->u.z3950->u.presentResponse;
 629             f_resp->records = p_res->records;
 630             *f_resp->numberOfRecordsReturned =
 631                 *p_res->numberOfRecordsReturned;
 632             *f_resp->nextResultSetPosition =
 633                 *p_res->nextResultSetPosition;
 634         }
 635         else
 636         {
 637             package.response() = pp.response();
 638             return;
 639         }
 640     }
 641     package.response() = f_apdu; // in this scope because of p
 642 }
 643
 644 void yf::Multi::Frontend::present(mp::Package &package, Z_APDU *apdu_req)
 645 {
 646     // create present request
 647     Z_PresentRequest *req = apdu_req->u.presentRequest;
 648
 649     Sets_it it;
 650     it = m_sets.find(std::string(req->resultSetId));
 651     if (it == m_sets.end())
 652     {
 653         mp::odr odr;
 654         Z_APDU *apdu =
 655             odr.create_presentResponse(
 656                 apdu_req,
 657                 YAZ_BIB1_SPECIFIED_RESULT_SET_DOES_NOT_EXIST,
 658                 req->resultSetId);
 659         package.response() = apdu;
 660         return;
 661     }
 662     std::list<Multi::FrontendSet::PresentJob> jobs;
 663     int start = *req->resultSetStartPoint;
 664     int number = *req->numberOfRecordsRequested;
 665
 666     if (m_p->m_merge_type == round_robin)
 667         it->second.round_robin(start, number, jobs);
 668     else if (m_p->m_merge_type == serve_order)
 669         it->second.serve_order(start, number, jobs);
 670
 671     if (0)
 672     {
 673         std::list<Multi::FrontendSet::PresentJob>::const_iterator jit;
 674         for (jit = jobs.begin(); jit != jobs.end(); jit++)
 675         {
 676             yaz_log(YLOG_LOG, "job pos=%d", jit->m_pos);
 677         }
 678     }
 679
 680     std::list<BackendPtr> present_backend_list;
 681
 682     std::list<BackendSet>::const_iterator bsit;
 683     bsit = it->second.m_backend_sets.begin();
 684     for (; bsit != it->second.m_backend_sets.end(); bsit++)
 685     {
 686         int start = -1;
 687         int end = -1;
 688         {
 689             std::list<Multi::FrontendSet::PresentJob>::const_iterator jit;
 690             for (jit = jobs.begin(); jit != jobs.end(); jit++)
 691             {
 692                 if (jit->m_backend == bsit->m_backend)
 693                 {
 694                     if (start == -1 || jit->m_pos < start)
 695                         start = jit->m_pos;
 696                     if (end == -1 || jit->m_pos > end)
 697                         end = jit->m_pos;
 698                 }
 699             }
 700         }
 701         if (start != -1)
 702         {
 703             std::list<Multi::FrontendSet::PresentJob>::iterator jit;
 704             for (jit = jobs.begin(); jit != jobs.end(); jit++)
 705             {
 706                 if (jit->m_backend == bsit->m_backend)
 707                 {
 708                     if (jit->m_pos >= start && jit->m_pos <= end)
 709                         jit->m_start = start;
 710                 }
 711             }
 712
 713             PackagePtr p = bsit->m_backend->m_package;
 714
 715             *req->resultSetStartPoint = start;
 716             *req->numberOfRecordsRequested = end - start + 1;
 717
 718             p->request() = apdu_req;
 719             p->copy_filter(package);
 720
 721             present_backend_list.push_back(bsit->m_backend);
 722         }
 723     }
 724     multi_move(present_backend_list);
 725
 726     // look at each response
 727     Z_Records *z_records_diag = 0;
 728
 729     std::list<BackendPtr>::const_iterator pbit = present_backend_list.begin();
 730     for (; pbit != present_backend_list.end(); pbit++)
 731     {
 732         PackagePtr p = (*pbit)->m_package;
 733
 734         if (p->session().is_closed()) // if any backend closes, close frontend
 735             package.session().close();
 736
 737         Z_GDU *gdu = p->response().get();
 738         if (gdu && gdu->which == Z_GDU_Z3950 && gdu->u.z3950->which ==
 739             Z_APDU_presentResponse)
 740         {
 741             Z_APDU *b_apdu = gdu->u.z3950;
 742             Z_PresentResponse *b_resp = b_apdu->u.presentResponse;
 743
 744             // see we get any errors (AKA diagnstics)
 745             if (b_resp->records)
 746             {
 747                 if (b_resp->records->which != Z_Records_DBOSD)
 748                     z_records_diag = b_resp->records;
 749                 // we may set this multiple times (TOO BAD!)
 750             }
 751         }
 752         else
 753         {
 754             // if any target does not return present response - return that
 755             package.response() = p->response();
 756             return;
 757         }
 758     }
 759
 760     mp::odr odr;
 761     Z_APDU *f_apdu = odr.create_presentResponse(apdu_req, 0, 0);
 762     Z_PresentResponse *f_resp = f_apdu->u.presentResponse;
 763
 764     if (z_records_diag)
 765     {
 766         f_resp->records = z_records_diag;
 767         *f_resp->presentStatus = Z_PresentStatus_failure;
 768     }
 769     else
 770     {
 771         f_resp->records = (Z_Records *) odr_malloc(odr, sizeof(Z_Records));
 772         Z_Records * records = f_resp->records;
 773         records->which = Z_Records_DBOSD;
 774         records->u.databaseOrSurDiagnostics =
 775             (Z_NamePlusRecordList *)
 776             odr_malloc(odr, sizeof(Z_NamePlusRecordList));
 777         Z_NamePlusRecordList *nprl = records->u.databaseOrSurDiagnostics;
 778         nprl->num_records = jobs.size();
 779         nprl->records = (Z_NamePlusRecord**)
 780             odr_malloc(odr, sizeof(Z_NamePlusRecord *) * nprl->num_records);
 781         int i = 0;
 782         std::list<Multi::FrontendSet::PresentJob>::const_iterator jit;
 783         for (jit = jobs.begin(); jit != jobs.end(); jit++, i++)
 784         {
 785             PackagePtr p = jit->m_backend->m_package;
 786
 787             Z_GDU *gdu = p->response().get();
 788             Z_APDU *b_apdu = gdu->u.z3950;
 789             Z_PresentResponse *b_resp = b_apdu->u.presentResponse;
 790
 791             nprl->records[i] = (Z_NamePlusRecord*)
 792                 odr_malloc(odr, sizeof(Z_NamePlusRecord));
 793             int inside_pos = jit->m_pos - jit->m_start;
 794             if (inside_pos >= b_resp->records->
 795                 u.databaseOrSurDiagnostics->num_records)
 796                 break;
 797             *nprl->records[i] = *b_resp->records->
 798                 u.databaseOrSurDiagnostics->records[inside_pos];
 799             nprl->records[i]->databaseName =
 800                     odr_strdup(odr, jit->m_backend->m_vhost.c_str());
 801         }
 802         nprl->num_records = i; // usually same as jobs.size();
 803         *f_resp->nextResultSetPosition = start + i;
 804         *f_resp->numberOfRecordsReturned = i;
 805     }
 806     package.response() = f_apdu;
 807 }
 808
 809 void yf::Multi::Frontend::scan1(mp::Package &package, Z_APDU *apdu_req)
 810 {
 811     if (m_backend_list.size() > 1)
 812     {
 813         mp::odr odr;
 814         Z_APDU *f_apdu =
 815             odr.create_scanResponse(
 816                 apdu_req, YAZ_BIB1_COMBI_OF_SPECIFIED_DATABASES_UNSUPP, 0);
 817         package.response() = f_apdu;
 818         return;
 819     }
 820     Z_ScanRequest *req = apdu_req->u.scanRequest;
 821
 822     int default_num_db = req->num_databaseNames;
 823     char **default_db = req->databaseNames;
 824
 825     std::list<BackendPtr>::const_iterator bit;
 826     for (bit = m_backend_list.begin(); bit != m_backend_list.end(); bit++)
 827     {
 828         PackagePtr p = (*bit)->m_package;
 829         mp::odr odr;
 830
 831         if (!mp::util::set_databases_from_zurl(odr, (*bit)->m_vhost,
 832                                                 &req->num_databaseNames,
 833                                                 &req->databaseNames))
 834         {
 835             req->num_databaseNames = default_num_db;
 836             req->databaseNames = default_db;
 837         }
 838         p->request() = apdu_req;
 839         p->copy_filter(package);
 840     }
 841     multi_move(m_backend_list);
 842
 843     for (bit = m_backend_list.begin(); bit != m_backend_list.end(); bit++)
 844     {
 845         PackagePtr p = (*bit)->m_package;
 846
 847         if (p->session().is_closed()) // if any backend closes, close frontend
 848             package.session().close();
 849
 850         Z_GDU *gdu = p->response().get();
 851         if (gdu && gdu->which == Z_GDU_Z3950 && gdu->u.z3950->which ==
 852             Z_APDU_scanResponse)
 853         {
 854             package.response() = p->response();
 855             break;
 856         }
 857         else
 858         {
 859             // if any target does not return scan response - return that
 860             package.response() = p->response();
 861             return;
 862         }
 863     }
 864 }
 865
 866 bool yf::Multi::ScanTermInfo::operator < (const ScanTermInfo &k) const
 867 {
 868     return m_norm_term < k.m_norm_term;
 869 }
 870
 871 bool yf::Multi::ScanTermInfo::operator == (const ScanTermInfo &k) const
 872 {
 873     return m_norm_term == k.m_norm_term;
 874 }
 875
 876 Z_Entry *yf::Multi::ScanTermInfo::get_entry(ODR odr)
 877 {
 878     Z_Entry *e = (Z_Entry *)odr_malloc(odr, sizeof(*e));
 879     e->which = Z_Entry_termInfo;
 880     Z_TermInfo *t;
 881     t = e->u.termInfo = (Z_TermInfo *) odr_malloc(odr, sizeof(*t));
 882     t->suggestedAttributes = 0;
 883     t->displayTerm = 0;
 884     t->alternativeTerm = 0;
 885     t->byAttributes = 0;
 886     t->otherTermInfo = 0;
 887     t->globalOccurrences = odr_intdup(odr, m_count);
 888     t->term = (Z_Term *)
 889         odr_malloc(odr, sizeof(*t->term));
 890     t->term->which = Z_Term_general;
 891     Odr_oct *o;
 892     t->term->u.general = o = (Odr_oct *)odr_malloc(odr, sizeof(Odr_oct));
 893
 894     o->len = o->size = m_norm_term.size();
 895     o->buf = (unsigned char *) odr_malloc(odr, o->len);
 896     memcpy(o->buf, m_norm_term.c_str(), o->len);
 897     return e;
 898 }
 899
 900 void yf::Multi::Frontend::scan2(mp::Package &package, Z_APDU *apdu_req)
 901 {
 902     Z_ScanRequest *req = apdu_req->u.scanRequest;
 903
 904     int default_num_db = req->num_databaseNames;
 905     char **default_db = req->databaseNames;
 906
 907     std::list<BackendPtr>::const_iterator bit;
 908     for (bit = m_backend_list.begin(); bit != m_backend_list.end(); bit++)
 909     {
 910         PackagePtr p = (*bit)->m_package;
 911         mp::odr odr;
 912
 913         if (!mp::util::set_databases_from_zurl(odr, (*bit)->m_vhost,
 914                                                 &req->num_databaseNames,
 915                                                 &req->databaseNames))
 916         {
 917             req->num_databaseNames = default_num_db;
 918             req->databaseNames = default_db;
 919         }
 920         p->request() = apdu_req;
 921         p->copy_filter(package);
 922     }
 923     multi_move(m_backend_list);
 924
 925     ScanTermInfoList entries_before;
 926     ScanTermInfoList entries_after;
 927     int no_before = 0;
 928     int no_after = 0;
 929
 930     for (bit = m_backend_list.begin(); bit != m_backend_list.end(); bit++)
 931     {
 932         PackagePtr p = (*bit)->m_package;
 933
 934         if (p->session().is_closed()) // if any backend closes, close frontend
 935             package.session().close();
 936
 937         Z_GDU *gdu = p->response().get();
 938         if (gdu && gdu->which == Z_GDU_Z3950 && gdu->u.z3950->which ==
 939             Z_APDU_scanResponse)
 940         {
 941             Z_ScanResponse *res = gdu->u.z3950->u.scanResponse;
 942
 943             if (res->entries && res->entries->nonsurrogateDiagnostics)
 944             {
 945                 // failure
 946                 mp::odr odr;
 947                 Z_APDU *f_apdu = odr.create_scanResponse(apdu_req, 1, 0);
 948                 Z_ScanResponse *f_res = f_apdu->u.scanResponse;
 949
 950                 f_res->entries->nonsurrogateDiagnostics =
 951                     res->entries->nonsurrogateDiagnostics;
 952                 f_res->entries->num_nonsurrogateDiagnostics =
 953                     res->entries->num_nonsurrogateDiagnostics;
 954
 955                 package.response() = f_apdu;
 956                 return;
 957             }
 958
 959             if (res->entries && res->entries->entries)
 960             {
 961                 Z_Entry **entries = res->entries->entries;
 962                 int num_entries = res->entries->num_entries;
 963                 int position = 1;
 964                 if (req->preferredPositionInResponse)
 965                     position = *req->preferredPositionInResponse;
 966                 if (res->positionOfTerm)
 967                     position = *res->positionOfTerm;
 968
 969                 // before
 970                 int i;
 971                 for (i = 0; i<position-1 && i<num_entries; i++)
 972                 {
 973                     Z_Entry *ent = entries[i];
 974
 975                     if (ent->which == Z_Entry_termInfo)
 976                     {
 977                         ScanTermInfo my;
 978
 979                         int *occur = ent->u.termInfo->globalOccurrences;
 980                         my.m_count = occur ? *occur : 0;
 981
 982                         if (ent->u.termInfo->term->which == Z_Term_general)
 983                         {
 984                             my.m_norm_term = std::string(
 985                                 (const char *)
 986                                 ent->u.termInfo->term->u.general->buf,
 987                                 ent->u.termInfo->term->u.general->len);
 988                         }
 989                         if (my.m_norm_term.length())
 990                         {
 991                             ScanTermInfoList::iterator it =
 992                                 entries_before.begin();
 993                             while (it != entries_before.end() && my <*it)
 994                                 it++;
 995                             if (my == *it)
 996                             {
 997                                 it->m_count += my.m_count;
 998                             }
 999                             else
1000                             {
1001                                 entries_before.insert(it, my);
1002                                 no_before++;
1003                             }
1004                         }
1005                     }
1006                 }
1007                 // after
1008                 if (position <= 0)
1009                     i = 0;
1010                 else
1011                     i = position-1;
1012                 for ( ; i<num_entries; i++)
1013                 {
1014                     Z_Entry *ent = entries[i];
1015
1016                     if (ent->which == Z_Entry_termInfo)
1017                     {
1018                         ScanTermInfo my;
1019
1020                         int *occur = ent->u.termInfo->globalOccurrences;
1021                         my.m_count = occur ? *occur : 0;
1022
1023                         if (ent->u.termInfo->term->which == Z_Term_general)
1024                         {
1025                             my.m_norm_term = std::string(
1026                                 (const char *)
1027                                 ent->u.termInfo->term->u.general->buf,
1028                                 ent->u.termInfo->term->u.general->len);
1029                         }
1030                         if (my.m_norm_term.length())
1031                         {
1032                             ScanTermInfoList::iterator it =
1033                                 entries_after.begin();
1034                             while (it != entries_after.end() && *it < my)
1035                                 it++;
1036                             if (my == *it)
1037                             {
1038                                 it->m_count += my.m_count;
1039                             }
1040                             else
1041                             {
1042                                 entries_after.insert(it, my);
1043                                 no_after++;
1044                             }
1045                         }
1046                     }
1047                 }
1048
1049             }
1050         }
1051         else
1052         {
1053             // if any target does not return scan response - return that
1054             package.response() = p->response();
1055             return;
1056         }
1057     }
1058
1059     if (false)
1060     {
1061         std::cout << "BEFORE\n";
1062         ScanTermInfoList::iterator it = entries_before.begin();
1063         for(; it != entries_before.end(); it++)
1064         {
1065             std::cout << " " << it->m_norm_term << " " << it->m_count << "\n";
1066         }
1067
1068         std::cout << "AFTER\n";
1069         it = entries_after.begin();
1070         for(; it != entries_after.end(); it++)
1071         {
1072             std::cout << " " << it->m_norm_term << " " << it->m_count << "\n";
1073         }
1074     }
1075
1076     if (false)
1077     {
1078         mp::odr odr;
1079         Z_APDU *f_apdu = odr.create_scanResponse(apdu_req, 1, "not implemented");
1080         package.response() = f_apdu;
1081     }
1082     else
1083     {
1084         mp::odr odr;
1085         Z_APDU *f_apdu = odr.create_scanResponse(apdu_req, 0, 0);
1086         Z_ScanResponse *resp = f_apdu->u.scanResponse;
1087
1088         int number_returned = *req->numberOfTermsRequested;
1089         int position_returned = *req->preferredPositionInResponse;
1090
1091         resp->entries->num_entries = number_returned;
1092         resp->entries->entries = (Z_Entry**)
1093             odr_malloc(odr, sizeof(Z_Entry*) * number_returned);
1094         int i;
1095
1096         int lbefore = entries_before.size();
1097         if (lbefore < position_returned-1)
1098             position_returned = lbefore+1;
1099
1100         ScanTermInfoList::iterator it = entries_before.begin();
1101         for (i = 0; i<position_returned-1 && it != entries_before.end(); i++, it++)
1102         {
1103             resp->entries->entries[position_returned-2-i] = it->get_entry(odr);
1104         }
1105
1106         it = entries_after.begin();
1107
1108         if (position_returned <= 0)
1109             i = 0;
1110         else
1111             i = position_returned-1;
1112         for (; i<number_returned && it != entries_after.end(); i++, it++)
1113         {
1114             resp->entries->entries[i] = it->get_entry(odr);
1115         }
1116
1117         number_returned = i;
1118
1119         resp->positionOfTerm = odr_intdup(odr, position_returned);
1120         resp->numberOfEntriesReturned = odr_intdup(odr, number_returned);
1121         resp->entries->num_entries = number_returned;
1122
1123         package.response() = f_apdu;
1124     }
1125 }
1126
1127
1128 void yf::Multi::process(mp::Package &package) const
1129 {
1130     FrontendPtr f = m_p->get_frontend(package);
1131
1132     Z_GDU *gdu = package.request().get();
1133
1134     if (gdu && gdu->which == Z_GDU_Z3950 && gdu->u.z3950->which ==
1135         Z_APDU_initRequest && !f->m_is_multi)
1136     {
1137         f->init(package, gdu);
1138     }
1139     else if (!f->m_is_multi)
1140         package.move();
1141     else if (gdu && gdu->which == Z_GDU_Z3950)
1142     {
1143         Z_APDU *apdu = gdu->u.z3950;
1144         if (apdu->which == Z_APDU_initRequest)
1145         {
1146             mp::odr odr;
1147
1148             package.response() = odr.create_close(
1149                 apdu,
1150                 Z_Close_protocolError,
1151                 "double init");
1152
1153             package.session().close();
1154         }
1155         else if (apdu->which == Z_APDU_searchRequest)
1156         {
1157             f->search(package, apdu);
1158         }
1159         else if (apdu->which == Z_APDU_presentRequest)
1160         {
1161             f->present(package, apdu);
1162         }
1163         else if (apdu->which == Z_APDU_scanRequest)
1164         {
1165             f->scan2(package, apdu);
1166         }
1167         else
1168         {
1169             mp::odr odr;
1170
1171             package.response() = odr.create_close(
1172                 apdu, Z_Close_protocolError,
1173                 "unsupported APDU in filter multi");
1174
1175             package.session().close();
1176         }
1177     }
1178     m_p->release_frontend(package);
1179 }
1180
1181 void mp::filter::Multi::configure(const xmlNode * ptr, bool test_only)
1182 {
1183     for (ptr = ptr->children; ptr; ptr = ptr->next)
1184     {
1185         if (ptr->type != XML_ELEMENT_NODE)
1186             continue;
1187         if (!strcmp((const char *) ptr->name, "target"))
1188         {
1189             std::string route = mp::xml::get_route(ptr);
1190             std::string target = mp::xml::get_text(ptr);
1191             m_p->m_route_patterns.push_back(Multi::Map(target, route));
1192         }
1193         else if (!strcmp((const char *) ptr->name, "hideunavailable"))
1194         {
1195             m_p->m_hide_unavailable = true;
1196         }
1197         else if (!strcmp((const char *) ptr->name, "mergetype"))
1198         {
1199             std::string mergetype = mp::xml::get_text(ptr);
1200             if (mergetype == "roundrobin")
1201                 m_p->m_merge_type = round_robin;
1202             else if (mergetype == "serveorder")
1203                 m_p->m_merge_type = serve_order;
1204             else
1205                 throw mp::filter::FilterException
1206                     ("Bad mergetype "  + mergetype + " in multi filter");
1207
1208         }
1209         else
1210         {
1211             throw mp::filter::FilterException
1212                 ("Bad element "
1213                  + std::string((const char *) ptr->name)
1214                  + " in multi filter");
1215         }
1216     }
1217 }
1218
1219 static mp::filter::Base* filter_creator()
1220 {
1221     return new mp::filter::Multi;
1222 }
1223
1224 extern "C" {
1225     struct metaproxy_1_filter_struct metaproxy_1_filter_multi = {
1226         0,
1227         "multi",
1228         filter_creator
1229     };
1230 }
1231
1232
1233 /*
1234  * Local variables:
1235  * c-basic-offset: 4
1236  * c-file-style: "Stroustrup"
1237  * indent-tabs-mode: nil
1238  * End:
1239  * vim: shiftwidth=4 tabstop=8 expandtab
1240  */
1241