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             void relay_apdu(Package &package, Z_APDU *apdu);
 109             Rep *m_p;
 110         };
 111         class Multi::Map {
 112             std::string m_target_pattern;
 113             std::string m_route;
 114         public:
 115             Map(std::string pattern, std::string route) :
 116                 m_target_pattern(pattern), m_route(route) {};
 117             bool match(const std::string target, std::string *ret) const {
 118                 if (yaz_match_glob(m_target_pattern.c_str(), target.c_str()))
 119                 {
 120                     *ret = m_route;
 121                     return true;
 122                 }
 123                 return false;
 124             };
 125         };
 126         class Multi::Rep {
 127             friend class Multi;
 128             friend struct Frontend;
 129
 130             Rep();
 131             FrontendPtr get_frontend(Package &package);
 132             void release_frontend(Package &package);
 133         private:
 134             std::list<Multi::Map> m_route_patterns;
 135             boost::mutex m_mutex;
 136             boost::condition m_cond_session_ready;
 137             std::map<mp::Session, FrontendPtr> m_clients;
 138             bool m_hide_unavailable;
 139             multi_merge_type m_merge_type;
 140         };
 141     }
 142 }
 143
 144 yf::Multi::Rep::Rep()
 145 {
 146     m_hide_unavailable = false;
 147     m_merge_type = round_robin;
 148 }
 149
 150 bool yf::Multi::BackendSet::operator < (const BackendSet &k) const
 151 {
 152     return m_count < k.m_count;
 153 }
 154
 155 yf::Multi::Frontend::Frontend(Rep *rep)
 156 {
 157     m_p = rep;
 158     m_is_multi = false;
 159 }
 160
 161 yf::Multi::Frontend::~Frontend()
 162 {
 163 }
 164
 165 yf::Multi::FrontendPtr yf::Multi::Rep::get_frontend(mp::Package &package)
 166 {
 167     boost::mutex::scoped_lock lock(m_mutex);
 168
 169     std::map<mp::Session,yf::Multi::FrontendPtr>::iterator it;
 170
 171     while(true)
 172     {
 173         it = m_clients.find(package.session());
 174         if (it == m_clients.end())
 175             break;
 176
 177         if (!it->second->m_in_use)
 178         {
 179             it->second->m_in_use = true;
 180             return it->second;
 181         }
 182         m_cond_session_ready.wait(lock);
 183     }
 184     FrontendPtr f(new Frontend(this));
 185     m_clients[package.session()] = f;
 186     f->m_in_use = true;
 187     return f;
 188 }
 189
 190 void yf::Multi::Rep::release_frontend(mp::Package &package)
 191 {
 192     boost::mutex::scoped_lock lock(m_mutex);
 193     std::map<mp::Session,yf::Multi::FrontendPtr>::iterator it;
 194
 195     it = m_clients.find(package.session());
 196     if (it != m_clients.end())
 197     {
 198         if (package.session().is_closed())
 199         {
 200             it->second->close(package);
 201             m_clients.erase(it);
 202         }
 203         else
 204         {
 205             it->second->m_in_use = false;
 206         }
 207         m_cond_session_ready.notify_all();
 208     }
 209 }
 210
 211 yf::Multi::FrontendSet::FrontendSet(std::string setname)
 212     :  m_setname(setname)
 213 {
 214 }
 215
 216
 217 yf::Multi::FrontendSet::FrontendSet()
 218 {
 219 }
 220
 221
 222 yf::Multi::FrontendSet::~FrontendSet()
 223 {
 224 }
 225
 226 yf::Multi::Multi() : m_p(new Multi::Rep)
 227 {
 228 }
 229
 230 yf::Multi::~Multi() {
 231 }
 232
 233
 234 void yf::Multi::Backend::operator() (void)
 235 {
 236     m_package->move(m_route);
 237 }
 238
 239
 240 void yf::Multi::Frontend::close(mp::Package &package)
 241 {
 242     std::list<BackendPtr>::const_iterator bit;
 243     for (bit = m_backend_list.begin(); bit != m_backend_list.end(); bit++)
 244     {
 245         BackendPtr b = *bit;
 246
 247         b->m_package->copy_filter(package);
 248         b->m_package->request() = (Z_GDU *) 0;
 249         b->m_package->session().close();
 250         b->m_package->move(b->m_route);
 251     }
 252 }
 253
 254 void yf::Multi::Frontend::multi_move(std::list<BackendPtr> &blist)
 255 {
 256     std::list<BackendPtr>::const_iterator bit;
 257     boost::thread_group g;
 258     for (bit = blist.begin(); bit != blist.end(); bit++)
 259     {
 260         g.add_thread(new boost::thread(**bit));
 261     }
 262     g.join_all();
 263 }
 264
 265 void yf::Multi::FrontendSet::serve_order(int start, int number,
 266                                          std::list<PresentJob> &jobs)
 267 {
 268     int i;
 269     for (i = 0; i < number; i++)
 270     {
 271         std::list<BackendSet>::const_iterator bsit;
 272         int voffset = 0;
 273         int offset = start + i - 1;
 274         for (bsit = m_backend_sets.begin(); bsit != m_backend_sets.end();
 275              bsit++)
 276         {
 277             if (offset >= voffset && offset < voffset + bsit->m_count)
 278             {
 279                 PresentJob job(bsit->m_backend, offset - voffset + 1);
 280                 jobs.push_back(job);
 281                 break;
 282             }
 283             voffset += bsit->m_count;
 284         }
 285     }
 286 }
 287
 288 void yf::Multi::FrontendSet::round_robin(int start, int number,
 289                                          std::list<PresentJob> &jobs)
 290 {
 291     std::list<int> pos;
 292     std::list<BackendSet>::const_iterator bsit;
 293     for (bsit = m_backend_sets.begin(); bsit != m_backend_sets.end(); bsit++)
 294     {
 295         pos.push_back(1);
 296     }
 297
 298     int p = 1;
 299 #if 1
 300     // optimization step!
 301     int omin = 0;
 302     while(true)
 303     {
 304         int min = 0;
 305         int no_left = 0;
 306         // find min count for each set which is > omin
 307         for (bsit = m_backend_sets.begin(); bsit != m_backend_sets.end(); bsit++)
 308         {
 309             if (bsit->m_count > omin)
 310             {
 311                 if (no_left == 0 || bsit->m_count < min)
 312                     min = bsit->m_count;
 313                 no_left++;
 314             }
 315         }
 316         if (no_left == 0) // if nothing greater than omin, bail out.
 317             break;
 318         int skip = no_left * min;
 319         if (p + skip > start)  // step gets us "into" present range?
 320         {
 321             // Yes. skip until start.. Rounding off is deliberate!
 322             min = (start-p) / no_left;
 323             p += no_left * min;
 324
 325             // update positions in each set..
 326             std::list<int>::iterator psit = pos.begin();
 327             for (psit = pos.begin(); psit != pos.end(); psit++)
 328                 *psit += min;
 329             break;
 330         }
 331         // skip on each set.. before "present range"..
 332         p = p + skip;
 333
 334         std::list<int>::iterator psit = pos.begin();
 335         for (psit = pos.begin(); psit != pos.end(); psit++)
 336             *psit += min;
 337
 338         omin = min; // update so we consider next class (with higher count)
 339     }
 340 #endif
 341     int fetched = 0;
 342     bool more = true;
 343     while (more)
 344     {
 345         more = false;
 346         std::list<int>::iterator psit = pos.begin();
 347         bsit = m_backend_sets.begin();
 348
 349         for (; bsit != m_backend_sets.end(); psit++,bsit++)
 350         {
 351             if (fetched >= number)
 352             {
 353                 more = false;
 354                 break;
 355             }
 356             if (*psit <= bsit->m_count)
 357             {
 358                 if (p >= start)
 359                 {
 360                     PresentJob job(bsit->m_backend, *psit);
 361                     jobs.push_back(job);
 362                     fetched++;
 363                 }
 364                 (*psit)++;
 365                 p++;
 366                 more = true;
 367             }
 368         }
 369     }
 370 }
 371
 372 void yf::Multi::Frontend::init(mp::Package &package, Z_GDU *gdu)
 373 {
 374     Z_InitRequest *req = gdu->u.z3950->u.initRequest;
 375
 376     std::list<std::string> targets;
 377
 378     mp::util::get_vhost_otherinfo(req->otherInfo, targets);
 379
 380     if (targets.size() < 1)
 381     {
 382         package.move();
 383         return;
 384     }
 385
 386     std::list<std::string>::const_iterator t_it = targets.begin();
 387     for (; t_it != targets.end(); t_it++)
 388     {
 389         Session s;
 390         Backend *b = new Backend;
 391         b->m_vhost = *t_it;
 392
 393         std::list<Multi::Map>::const_iterator it =
 394             m_p->m_route_patterns.begin();
 395         while (it != m_p->m_route_patterns.end()) {
 396             if (it->match(*t_it, &b->m_route))
 397                 break;
 398             it++;
 399         }
 400         // b->m_route = m_p->m_target_route[*t_it];
 401         // b->m_route unset
 402         b->m_package = PackagePtr(new Package(s, package.origin()));
 403
 404         m_backend_list.push_back(BackendPtr(b));
 405     }
 406     m_is_multi = true;
 407
 408     // create init request
 409     std::list<BackendPtr>::iterator bit;
 410     for (bit = m_backend_list.begin(); bit != m_backend_list.end(); bit++)
 411     {
 412         mp::odr odr;
 413         BackendPtr b = *bit;
 414         Z_APDU *init_apdu = zget_APDU(odr, Z_APDU_initRequest);
 415
 416         std::list<std::string>vhost_one;
 417         vhost_one.push_back(b->m_vhost);
 418         mp::util::set_vhost_otherinfo(&init_apdu->u.initRequest->otherInfo,
 419                                        odr, vhost_one);
 420
 421
 422         Z_InitRequest *breq = init_apdu->u.initRequest;
 423
 424         breq->idAuthentication = req->idAuthentication;
 425
 426         *breq->preferredMessageSize = *req->preferredMessageSize;
 427         *breq->maximumRecordSize = *req->maximumRecordSize;
 428
 429         ODR_MASK_SET(breq->options, Z_Options_search);
 430         ODR_MASK_SET(breq->options, Z_Options_present);
 431         ODR_MASK_SET(breq->options, Z_Options_namedResultSets);
 432         ODR_MASK_SET(breq->options, Z_Options_scan);
 433
 434         ODR_MASK_SET(breq->protocolVersion, Z_ProtocolVersion_1);
 435         ODR_MASK_SET(breq->protocolVersion, Z_ProtocolVersion_2);
 436         ODR_MASK_SET(breq->protocolVersion, Z_ProtocolVersion_3);
 437
 438         b->m_package->request() = init_apdu;
 439
 440         b->m_package->copy_filter(package);
 441     }
 442     multi_move(m_backend_list);
 443
 444     // create the frontend init response based on each backend init response
 445     mp::odr odr;
 446
 447     Z_APDU *f_apdu = odr.create_initResponse(gdu->u.z3950, 0, 0);
 448     Z_InitResponse *f_resp = f_apdu->u.initResponse;
 449
 450     ODR_MASK_SET(f_resp->options, Z_Options_search);
 451     ODR_MASK_SET(f_resp->options, Z_Options_present);
 452     ODR_MASK_SET(f_resp->options, Z_Options_namedResultSets);
 453     ODR_MASK_SET(f_resp->options, Z_Options_scan);
 454
 455     ODR_MASK_SET(f_resp->protocolVersion, Z_ProtocolVersion_1);
 456     ODR_MASK_SET(f_resp->protocolVersion, Z_ProtocolVersion_2);
 457     ODR_MASK_SET(f_resp->protocolVersion, Z_ProtocolVersion_3);
 458
 459     int no_failed = 0;
 460     int no_succeeded = 0;
 461
 462     Odr_int preferredMessageSize = *req->preferredMessageSize;
 463     Odr_int maximumRecordSize = *req->maximumRecordSize;
 464     for (bit = m_backend_list.begin(); bit != m_backend_list.end(); )
 465     {
 466         PackagePtr p = (*bit)->m_package;
 467
 468         if (p->session().is_closed())
 469         {
 470             // failed. Remove from list and increment number of failed
 471             no_failed++;
 472             bit = m_backend_list.erase(bit);
 473             continue;
 474         }
 475         Z_GDU *gdu = p->response().get();
 476         if (gdu && gdu->which == Z_GDU_Z3950 && gdu->u.z3950->which ==
 477             Z_APDU_initResponse)
 478         {
 479             int i;
 480             Z_APDU *b_apdu = gdu->u.z3950;
 481             Z_InitResponse *b_resp = b_apdu->u.initResponse;
 482
 483             // common options for all backends
 484             for (i = 0; i <= Z_Options_stringSchema; i++)
 485             {
 486                 if (!ODR_MASK_GET(b_resp->options, i))
 487                     ODR_MASK_CLEAR(f_resp->options, i);
 488             }
 489             // common protocol version
 490             for (i = 0; i <= Z_ProtocolVersion_3; i++)
 491                 if (!ODR_MASK_GET(b_resp->protocolVersion, i))
 492                     ODR_MASK_CLEAR(f_resp->protocolVersion, i);
 493             if (*b_resp->result)
 494             {
 495                 no_succeeded++;
 496                 if (preferredMessageSize > *b_resp->preferredMessageSize)
 497                     preferredMessageSize = *b_resp->preferredMessageSize;
 498                 if (maximumRecordSize > *b_resp->maximumRecordSize)
 499                     maximumRecordSize = *b_resp->maximumRecordSize;
 500             }
 501             else
 502                 no_failed++;
 503         }
 504         else
 505             no_failed++;
 506         bit++;
 507     }
 508     *f_resp->preferredMessageSize = preferredMessageSize;
 509     *f_resp->maximumRecordSize = maximumRecordSize;
 510
 511     if (m_p->m_hide_unavailable)
 512     {
 513         if (no_succeeded == 0)
 514         {
 515             *f_resp->result = 0;
 516             package.session().close();
 517         }
 518     }
 519     else
 520     {
 521         if (no_failed)
 522         {
 523             *f_resp->result = 0;
 524             package.session().close();
 525         }
 526     }
 527     package.response() = f_apdu;
 528 }
 529
 530 void yf::Multi::Frontend::search(mp::Package &package, Z_APDU *apdu_req)
 531 {
 532     // create search request
 533     Z_SearchRequest *req = apdu_req->u.searchRequest;
 534
 535     // save these for later
 536     Odr_int smallSetUpperBound = *req->smallSetUpperBound;
 537     Odr_int largeSetLowerBound = *req->largeSetLowerBound;
 538     Odr_int mediumSetPresentNumber = *req->mediumSetPresentNumber;
 539
 540     // they are altered now - to disable piggyback
 541     *req->smallSetUpperBound = 0;
 542     *req->largeSetLowerBound = 1;
 543     *req->mediumSetPresentNumber = 1;
 544
 545     int default_num_db = req->num_databaseNames;
 546     char **default_db = req->databaseNames;
 547
 548     std::list<BackendPtr>::const_iterator bit;
 549     for (bit = m_backend_list.begin(); bit != m_backend_list.end(); bit++)
 550     {
 551         PackagePtr p = (*bit)->m_package;
 552         mp::odr odr;
 553
 554         if (!mp::util::set_databases_from_zurl(odr, (*bit)->m_vhost,
 555                                                 &req->num_databaseNames,
 556                                                 &req->databaseNames))
 557         {
 558             req->num_databaseNames = default_num_db;
 559             req->databaseNames = default_db;
 560         }
 561         p->request() = apdu_req;
 562         p->copy_filter(package);
 563     }
 564     multi_move(m_backend_list);
 565
 566     // look at each response
 567     FrontendSet resultSet(std::string(req->resultSetName));
 568
 569     Odr_int result_set_size = 0;
 570     Z_Records *z_records_diag = 0;  // no diagnostics (yet)
 571     for (bit = m_backend_list.begin(); bit != m_backend_list.end(); bit++)
 572     {
 573         PackagePtr p = (*bit)->m_package;
 574
 575         if (p->session().is_closed()) // if any backend closes, close frontend
 576             package.session().close();
 577
 578         Z_GDU *gdu = p->response().get();
 579         if (gdu && gdu->which == Z_GDU_Z3950 && gdu->u.z3950->which ==
 580             Z_APDU_searchResponse)
 581         {
 582             Z_APDU *b_apdu = gdu->u.z3950;
 583             Z_SearchResponse *b_resp = b_apdu->u.searchResponse;
 584
 585             // see we get any errors (AKA diagnstics)
 586             if (b_resp->records)
 587             {
 588                 if (b_resp->records->which == Z_Records_NSD
 589                     || b_resp->records->which == Z_Records_multipleNSD)
 590                     z_records_diag = b_resp->records;
 591                 // we may set this multiple times (TOO BAD!)
 592             }
 593             BackendSet backendSet;
 594             backendSet.m_backend = *bit;
 595             backendSet.m_count = *b_resp->resultCount;
 596             result_set_size += *b_resp->resultCount;
 597             resultSet.m_backend_sets.push_back(backendSet);
 598         }
 599         else
 600         {
 601             // if any target does not return search response - return that
 602             package.response() = p->response();
 603             return;
 604         }
 605     }
 606
 607     mp::odr odr;
 608     Z_APDU *f_apdu = odr.create_searchResponse(apdu_req, 0, 0);
 609     Z_SearchResponse *f_resp = f_apdu->u.searchResponse;
 610
 611     *f_resp->resultCount = result_set_size;
 612     if (z_records_diag)
 613     {
 614         // search error
 615         f_resp->records = z_records_diag;
 616         package.response() = f_apdu;
 617         return;
 618     }
 619     // assume OK
 620     m_sets[resultSet.m_setname] = resultSet;
 621
 622     Odr_int number;
 623     mp::util::piggyback(smallSetUpperBound,
 624                         largeSetLowerBound,
 625                         mediumSetPresentNumber,
 626                         0, 0,
 627                         result_set_size,
 628                         number, 0);
 629     Package pp(package.session(), package.origin());
 630     if (number > 0)
 631     {
 632         pp.copy_filter(package);
 633         Z_APDU *p_apdu = zget_APDU(odr, Z_APDU_presentRequest);
 634         Z_PresentRequest *p_req = p_apdu->u.presentRequest;
 635         p_req->preferredRecordSyntax = req->preferredRecordSyntax;
 636         p_req->resultSetId = req->resultSetName;
 637         *p_req->resultSetStartPoint = 1;
 638         *p_req->numberOfRecordsRequested = number;
 639         pp.request() = p_apdu;
 640         present(pp, p_apdu);
 641
 642         if (pp.session().is_closed())
 643             package.session().close();
 644
 645         Z_GDU *gdu = pp.response().get();
 646         if (gdu && gdu->which == Z_GDU_Z3950 && gdu->u.z3950->which ==
 647             Z_APDU_presentResponse)
 648         {
 649             Z_PresentResponse *p_res = gdu->u.z3950->u.presentResponse;
 650             f_resp->records = p_res->records;
 651             *f_resp->numberOfRecordsReturned =
 652                 *p_res->numberOfRecordsReturned;
 653             *f_resp->nextResultSetPosition =
 654                 *p_res->nextResultSetPosition;
 655         }
 656         else
 657         {
 658             package.response() = pp.response();
 659             return;
 660         }
 661     }
 662     package.response() = f_apdu; // in this scope because of p
 663 }
 664
 665 void yf::Multi::Frontend::present(mp::Package &package, Z_APDU *apdu_req)
 666 {
 667     // create present request
 668     Z_PresentRequest *req = apdu_req->u.presentRequest;
 669
 670     Sets_it it;
 671     it = m_sets.find(std::string(req->resultSetId));
 672     if (it == m_sets.end())
 673     {
 674         mp::odr odr;
 675         Z_APDU *apdu =
 676             odr.create_presentResponse(
 677                 apdu_req,
 678                 YAZ_BIB1_SPECIFIED_RESULT_SET_DOES_NOT_EXIST,
 679                 req->resultSetId);
 680         package.response() = apdu;
 681         return;
 682     }
 683     std::list<Multi::FrontendSet::PresentJob> jobs;
 684     int start = *req->resultSetStartPoint;
 685     int number = *req->numberOfRecordsRequested;
 686
 687     if (m_p->m_merge_type == round_robin)
 688         it->second.round_robin(start, number, jobs);
 689     else if (m_p->m_merge_type == serve_order)
 690         it->second.serve_order(start, number, jobs);
 691
 692     if (0)
 693     {
 694         std::list<Multi::FrontendSet::PresentJob>::const_iterator jit;
 695         for (jit = jobs.begin(); jit != jobs.end(); jit++)
 696         {
 697             yaz_log(YLOG_LOG, "job pos=%d", jit->m_pos);
 698         }
 699     }
 700
 701     std::list<BackendPtr> present_backend_list;
 702
 703     std::list<BackendSet>::const_iterator bsit;
 704     bsit = it->second.m_backend_sets.begin();
 705     for (; bsit != it->second.m_backend_sets.end(); bsit++)
 706     {
 707         int start = -1;
 708         int end = -1;
 709         {
 710             std::list<Multi::FrontendSet::PresentJob>::const_iterator jit;
 711             for (jit = jobs.begin(); jit != jobs.end(); jit++)
 712             {
 713                 if (jit->m_backend == bsit->m_backend)
 714                 {
 715                     if (start == -1 || jit->m_pos < start)
 716                         start = jit->m_pos;
 717                     if (end == -1 || jit->m_pos > end)
 718                         end = jit->m_pos;
 719                 }
 720             }
 721         }
 722         if (start != -1)
 723         {
 724             std::list<Multi::FrontendSet::PresentJob>::iterator jit;
 725             for (jit = jobs.begin(); jit != jobs.end(); jit++)
 726             {
 727                 if (jit->m_backend == bsit->m_backend)
 728                 {
 729                     if (jit->m_pos >= start && jit->m_pos <= end)
 730                         jit->m_start = start;
 731                 }
 732             }
 733
 734             PackagePtr p = bsit->m_backend->m_package;
 735
 736             *req->resultSetStartPoint = start;
 737             *req->numberOfRecordsRequested = end - start + 1;
 738
 739             p->request() = apdu_req;
 740             p->copy_filter(package);
 741
 742             present_backend_list.push_back(bsit->m_backend);
 743         }
 744     }
 745     multi_move(present_backend_list);
 746
 747     // look at each response
 748     Z_Records *z_records_diag = 0;
 749
 750     std::list<BackendPtr>::const_iterator pbit = present_backend_list.begin();
 751     for (; pbit != present_backend_list.end(); pbit++)
 752     {
 753         PackagePtr p = (*pbit)->m_package;
 754
 755         if (p->session().is_closed()) // if any backend closes, close frontend
 756             package.session().close();
 757
 758         Z_GDU *gdu = p->response().get();
 759         if (gdu && gdu->which == Z_GDU_Z3950 && gdu->u.z3950->which ==
 760             Z_APDU_presentResponse)
 761         {
 762             Z_APDU *b_apdu = gdu->u.z3950;
 763             Z_PresentResponse *b_resp = b_apdu->u.presentResponse;
 764
 765             // see we get any errors (AKA diagnstics)
 766             if (b_resp->records)
 767             {
 768                 if (b_resp->records->which != Z_Records_DBOSD)
 769                     z_records_diag = b_resp->records;
 770                 // we may set this multiple times (TOO BAD!)
 771             }
 772         }
 773         else
 774         {
 775             // if any target does not return present response - return that
 776             package.response() = p->response();
 777             return;
 778         }
 779     }
 780
 781     mp::odr odr;
 782     Z_APDU *f_apdu = odr.create_presentResponse(apdu_req, 0, 0);
 783     Z_PresentResponse *f_resp = f_apdu->u.presentResponse;
 784
 785     if (z_records_diag)
 786     {
 787         f_resp->records = z_records_diag;
 788         *f_resp->presentStatus = Z_PresentStatus_failure;
 789     }
 790     else if (number < 0 || (size_t) number > jobs.size())
 791     {
 792         f_apdu =
 793             odr.create_presentResponse(
 794                 apdu_req,
 795                 YAZ_BIB1_PRESENT_REQUEST_OUT_OF_RANGE,
 796                 0);
 797     }
 798     else
 799     {
 800         f_resp->records = (Z_Records *) odr_malloc(odr, sizeof(Z_Records));
 801         Z_Records * records = f_resp->records;
 802         records->which = Z_Records_DBOSD;
 803         records->u.databaseOrSurDiagnostics =
 804             (Z_NamePlusRecordList *)
 805             odr_malloc(odr, sizeof(Z_NamePlusRecordList));
 806         Z_NamePlusRecordList *nprl = records->u.databaseOrSurDiagnostics;
 807         nprl->num_records = jobs.size();
 808         nprl->records = (Z_NamePlusRecord**)
 809             odr_malloc(odr, sizeof(Z_NamePlusRecord *) * nprl->num_records);
 810         int i = 0;
 811         std::list<Multi::FrontendSet::PresentJob>::const_iterator jit;
 812         for (jit = jobs.begin(); jit != jobs.end(); jit++, i++)
 813         {
 814             PackagePtr p = jit->m_backend->m_package;
 815
 816             Z_GDU *gdu = p->response().get();
 817             Z_APDU *b_apdu = gdu->u.z3950;
 818             Z_PresentResponse *b_resp = b_apdu->u.presentResponse;
 819
 820             nprl->records[i] = (Z_NamePlusRecord*)
 821                 odr_malloc(odr, sizeof(Z_NamePlusRecord));
 822             int inside_pos = jit->m_pos - jit->m_start;
 823             if (inside_pos >= b_resp->records->
 824                 u.databaseOrSurDiagnostics->num_records)
 825                 break;
 826             *nprl->records[i] = *b_resp->records->
 827                 u.databaseOrSurDiagnostics->records[inside_pos];
 828             nprl->records[i]->databaseName =
 829                     odr_strdup(odr, jit->m_backend->m_vhost.c_str());
 830         }
 831         nprl->num_records = i; // usually same as jobs.size();
 832         *f_resp->nextResultSetPosition = start + i;
 833         *f_resp->numberOfRecordsReturned = i;
 834     }
 835     package.response() = f_apdu;
 836 }
 837
 838 void yf::Multi::Frontend::scan1(mp::Package &package, Z_APDU *apdu_req)
 839 {
 840     if (m_backend_list.size() > 1)
 841     {
 842         mp::odr odr;
 843         Z_APDU *f_apdu =
 844             odr.create_scanResponse(
 845                 apdu_req, YAZ_BIB1_COMBI_OF_SPECIFIED_DATABASES_UNSUPP, 0);
 846         package.response() = f_apdu;
 847         return;
 848     }
 849     Z_ScanRequest *req = apdu_req->u.scanRequest;
 850
 851     int default_num_db = req->num_databaseNames;
 852     char **default_db = req->databaseNames;
 853
 854     std::list<BackendPtr>::const_iterator bit;
 855     for (bit = m_backend_list.begin(); bit != m_backend_list.end(); bit++)
 856     {
 857         PackagePtr p = (*bit)->m_package;
 858         mp::odr odr;
 859
 860         if (!mp::util::set_databases_from_zurl(odr, (*bit)->m_vhost,
 861                                                 &req->num_databaseNames,
 862                                                 &req->databaseNames))
 863         {
 864             req->num_databaseNames = default_num_db;
 865             req->databaseNames = default_db;
 866         }
 867         p->request() = apdu_req;
 868         p->copy_filter(package);
 869     }
 870     multi_move(m_backend_list);
 871
 872     for (bit = m_backend_list.begin(); bit != m_backend_list.end(); bit++)
 873     {
 874         PackagePtr p = (*bit)->m_package;
 875
 876         if (p->session().is_closed()) // if any backend closes, close frontend
 877             package.session().close();
 878
 879         Z_GDU *gdu = p->response().get();
 880         if (gdu && gdu->which == Z_GDU_Z3950 && gdu->u.z3950->which ==
 881             Z_APDU_scanResponse)
 882         {
 883             package.response() = p->response();
 884             break;
 885         }
 886         else
 887         {
 888             // if any target does not return scan response - return that
 889             package.response() = p->response();
 890             return;
 891         }
 892     }
 893 }
 894
 895 bool yf::Multi::ScanTermInfo::operator < (const ScanTermInfo &k) const
 896 {
 897     return m_norm_term < k.m_norm_term;
 898 }
 899
 900 bool yf::Multi::ScanTermInfo::operator == (const ScanTermInfo &k) const
 901 {
 902     return m_norm_term == k.m_norm_term;
 903 }
 904
 905 Z_Entry *yf::Multi::ScanTermInfo::get_entry(ODR odr)
 906 {
 907     Z_Entry *e = (Z_Entry *)odr_malloc(odr, sizeof(*e));
 908     e->which = Z_Entry_termInfo;
 909     Z_TermInfo *t;
 910     t = e->u.termInfo = (Z_TermInfo *) odr_malloc(odr, sizeof(*t));
 911     t->suggestedAttributes = 0;
 912     t->displayTerm = 0;
 913     t->alternativeTerm = 0;
 914     t->byAttributes = 0;
 915     t->otherTermInfo = 0;
 916     t->globalOccurrences = odr_intdup(odr, m_count);
 917     t->term = (Z_Term *)
 918         odr_malloc(odr, sizeof(*t->term));
 919     t->term->which = Z_Term_general;
 920     Odr_oct *o;
 921     t->term->u.general = o = (Odr_oct *)odr_malloc(odr, sizeof(Odr_oct));
 922
 923     o->len = o->size = m_norm_term.size();
 924     o->buf = (unsigned char *) odr_malloc(odr, o->len);
 925     memcpy(o->buf, m_norm_term.c_str(), o->len);
 926     return e;
 927 }
 928
 929 void yf::Multi::Frontend::relay_apdu(mp::Package &package, Z_APDU *apdu_req)
 930 {
 931     std::list<BackendPtr>::const_iterator bit;
 932     for (bit = m_backend_list.begin(); bit != m_backend_list.end(); bit++)
 933     {
 934         PackagePtr p = (*bit)->m_package;
 935         mp::odr odr;
 936
 937         p->request() = apdu_req;
 938         p->copy_filter(package);
 939     }
 940     multi_move(m_backend_list);
 941     for (bit = m_backend_list.begin(); bit != m_backend_list.end(); bit++)
 942     {
 943         PackagePtr p = (*bit)->m_package;
 944
 945         if (p->session().is_closed()) // if any backend closes, close frontend
 946             package.session().close();
 947
 948         package.response() = p->response();
 949     }
 950 }
 951
 952
 953 void yf::Multi::Frontend::scan2(mp::Package &package, Z_APDU *apdu_req)
 954 {
 955     Z_ScanRequest *req = apdu_req->u.scanRequest;
 956
 957     int default_num_db = req->num_databaseNames;
 958     char **default_db = req->databaseNames;
 959
 960     std::list<BackendPtr>::const_iterator bit;
 961     for (bit = m_backend_list.begin(); bit != m_backend_list.end(); bit++)
 962     {
 963         PackagePtr p = (*bit)->m_package;
 964         mp::odr odr;
 965
 966         if (!mp::util::set_databases_from_zurl(odr, (*bit)->m_vhost,
 967                                                 &req->num_databaseNames,
 968                                                 &req->databaseNames))
 969         {
 970             req->num_databaseNames = default_num_db;
 971             req->databaseNames = default_db;
 972         }
 973         p->request() = apdu_req;
 974         p->copy_filter(package);
 975     }
 976     multi_move(m_backend_list);
 977
 978     ScanTermInfoList entries_before;
 979     ScanTermInfoList entries_after;
 980     int no_before = 0;
 981     int no_after = 0;
 982
 983     for (bit = m_backend_list.begin(); bit != m_backend_list.end(); bit++)
 984     {
 985         PackagePtr p = (*bit)->m_package;
 986
 987         if (p->session().is_closed()) // if any backend closes, close frontend
 988             package.session().close();
 989
 990         Z_GDU *gdu = p->response().get();
 991         if (gdu && gdu->which == Z_GDU_Z3950 && gdu->u.z3950->which ==
 992             Z_APDU_scanResponse)
 993         {
 994             Z_ScanResponse *res = gdu->u.z3950->u.scanResponse;
 995
 996             if (res->entries && res->entries->nonsurrogateDiagnostics)
 997             {
 998                 // failure
 999                 mp::odr odr;
1000                 Z_APDU *f_apdu = odr.create_scanResponse(apdu_req, 1, 0);
1001                 Z_ScanResponse *f_res = f_apdu->u.scanResponse;
1002
1003                 f_res->entries->nonsurrogateDiagnostics =
1004                     res->entries->nonsurrogateDiagnostics;
1005                 f_res->entries->num_nonsurrogateDiagnostics =
1006                     res->entries->num_nonsurrogateDiagnostics;
1007
1008                 package.response() = f_apdu;
1009                 return;
1010             }
1011
1012             if (res->entries && res->entries->entries)
1013             {
1014                 Z_Entry **entries = res->entries->entries;
1015                 int num_entries = res->entries->num_entries;
1016                 int position = 1;
1017                 if (req->preferredPositionInResponse)
1018                     position = *req->preferredPositionInResponse;
1019                 if (res->positionOfTerm)
1020                     position = *res->positionOfTerm;
1021
1022                 // before
1023                 int i;
1024                 for (i = 0; i<position-1 && 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_before.begin();
1046                             while (it != entries_before.end() && my <*it)
1047                                 it++;
1048                             if (my == *it)
1049                             {
1050                                 it->m_count += my.m_count;
1051                             }
1052                             else
1053                             {
1054                                 entries_before.insert(it, my);
1055                                 no_before++;
1056                             }
1057                         }
1058                     }
1059                 }
1060                 // after
1061                 if (position <= 0)
1062                     i = 0;
1063                 else
1064                     i = position-1;
1065                 for ( ; i<num_entries; i++)
1066                 {
1067                     Z_Entry *ent = entries[i];
1068
1069                     if (ent->which == Z_Entry_termInfo)
1070                     {
1071                         ScanTermInfo my;
1072
1073                         Odr_int *occur = ent->u.termInfo->globalOccurrences;
1074                         my.m_count = occur ? *occur : 0;
1075
1076                         if (ent->u.termInfo->term->which == Z_Term_general)
1077                         {
1078                             my.m_norm_term = std::string(
1079                                 (const char *)
1080                                 ent->u.termInfo->term->u.general->buf,
1081                                 ent->u.termInfo->term->u.general->len);
1082                         }
1083                         if (my.m_norm_term.length())
1084                         {
1085                             ScanTermInfoList::iterator it =
1086                                 entries_after.begin();
1087                             while (it != entries_after.end() && *it < my)
1088                                 it++;
1089                             if (my == *it)
1090                             {
1091                                 it->m_count += my.m_count;
1092                             }
1093                             else
1094                             {
1095                                 entries_after.insert(it, my);
1096                                 no_after++;
1097                             }
1098                         }
1099                     }
1100                 }
1101
1102             }
1103         }
1104         else
1105         {
1106             // if any target does not return scan response - return that
1107             package.response() = p->response();
1108             return;
1109         }
1110     }
1111
1112     if (false)
1113     {
1114         std::cout << "BEFORE\n";
1115         ScanTermInfoList::iterator it = entries_before.begin();
1116         for(; it != entries_before.end(); it++)
1117         {
1118             std::cout << " " << it->m_norm_term << " " << it->m_count << "\n";
1119         }
1120
1121         std::cout << "AFTER\n";
1122         it = entries_after.begin();
1123         for(; it != entries_after.end(); it++)
1124         {
1125             std::cout << " " << it->m_norm_term << " " << it->m_count << "\n";
1126         }
1127     }
1128
1129     if (false)
1130     {
1131         mp::odr odr;
1132         Z_APDU *f_apdu = odr.create_scanResponse(apdu_req, 1, "not implemented");
1133         package.response() = f_apdu;
1134     }
1135     else
1136     {
1137         mp::odr odr;
1138         Z_APDU *f_apdu = odr.create_scanResponse(apdu_req, 0, 0);
1139         Z_ScanResponse *resp = f_apdu->u.scanResponse;
1140
1141         int number_returned = *req->numberOfTermsRequested;
1142         int position_returned = *req->preferredPositionInResponse;
1143
1144         resp->entries->num_entries = number_returned;
1145         resp->entries->entries = (Z_Entry**)
1146             odr_malloc(odr, sizeof(Z_Entry*) * number_returned);
1147         int i;
1148
1149         int lbefore = entries_before.size();
1150         if (lbefore < position_returned-1)
1151             position_returned = lbefore+1;
1152
1153         ScanTermInfoList::iterator it = entries_before.begin();
1154         for (i = 0; i<position_returned-1 && it != entries_before.end(); i++, it++)
1155         {
1156             resp->entries->entries[position_returned-2-i] = it->get_entry(odr);
1157         }
1158
1159         it = entries_after.begin();
1160
1161         if (position_returned <= 0)
1162             i = 0;
1163         else
1164             i = position_returned-1;
1165         for (; i<number_returned && it != entries_after.end(); i++, it++)
1166         {
1167             resp->entries->entries[i] = it->get_entry(odr);
1168         }
1169
1170         number_returned = i;
1171
1172         resp->positionOfTerm = odr_intdup(odr, position_returned);
1173         resp->numberOfEntriesReturned = odr_intdup(odr, number_returned);
1174         resp->entries->num_entries = number_returned;
1175
1176         package.response() = f_apdu;
1177     }
1178 }
1179
1180
1181 void yf::Multi::process(mp::Package &package) const
1182 {
1183     FrontendPtr f = m_p->get_frontend(package);
1184
1185     Z_GDU *gdu = package.request().get();
1186
1187     if (gdu && gdu->which == Z_GDU_Z3950 && gdu->u.z3950->which ==
1188         Z_APDU_initRequest && !f->m_is_multi)
1189     {
1190         f->init(package, gdu);
1191     }
1192     else if (!f->m_is_multi)
1193         package.move();
1194     else if (gdu && gdu->which == Z_GDU_Z3950)
1195     {
1196         Z_APDU *apdu = gdu->u.z3950;
1197         if (apdu->which == Z_APDU_initRequest)
1198         {
1199             mp::odr odr;
1200
1201             package.response() = odr.create_close(
1202                 apdu,
1203                 Z_Close_protocolError,
1204                 "double init");
1205
1206             package.session().close();
1207         }
1208         else if (apdu->which == Z_APDU_searchRequest)
1209         {
1210             f->search(package, apdu);
1211         }
1212         else if (apdu->which == Z_APDU_presentRequest)
1213         {
1214             f->present(package, apdu);
1215         }
1216         else if (apdu->which == Z_APDU_scanRequest)
1217         {
1218             f->scan2(package, apdu);
1219         }
1220         else if (apdu->which == Z_APDU_close)
1221         {
1222             f->relay_apdu(package, apdu);
1223         }
1224         else
1225         {
1226             mp::odr odr;
1227
1228             package.response() = odr.create_close(
1229                 apdu, Z_Close_protocolError,
1230                 "unsupported APDU in filter multi");
1231
1232             package.session().close();
1233         }
1234     }
1235     m_p->release_frontend(package);
1236 }
1237
1238 void mp::filter::Multi::configure(const xmlNode * ptr, bool test_only,
1239                                   const char *path)
1240 {
1241     for (ptr = ptr->children; ptr; ptr = ptr->next)
1242     {
1243         if (ptr->type != XML_ELEMENT_NODE)
1244             continue;
1245         if (!strcmp((const char *) ptr->name, "target"))
1246         {
1247             std::string route = mp::xml::get_route(ptr);
1248             std::string target = mp::xml::get_text(ptr);
1249             m_p->m_route_patterns.push_back(Multi::Map(target, route));
1250         }
1251         else if (!strcmp((const char *) ptr->name, "hideunavailable"))
1252         {
1253             m_p->m_hide_unavailable = true;
1254         }
1255         else if (!strcmp((const char *) ptr->name, "mergetype"))
1256         {
1257             std::string mergetype = mp::xml::get_text(ptr);
1258             if (mergetype == "roundrobin")
1259                 m_p->m_merge_type = round_robin;
1260             else if (mergetype == "serveorder")
1261                 m_p->m_merge_type = serve_order;
1262             else
1263                 throw mp::filter::FilterException
1264                     ("Bad mergetype "  + mergetype + " in multi filter");
1265
1266         }
1267         else
1268         {
1269             throw mp::filter::FilterException
1270                 ("Bad element "
1271                  + std::string((const char *) ptr->name)
1272                  + " in multi filter");
1273         }
1274     }
1275 }
1276
1277 static mp::filter::Base* filter_creator()
1278 {
1279     return new mp::filter::Multi;
1280 }
1281
1282 extern "C" {
1283     struct metaproxy_1_filter_struct metaproxy_1_filter_multi = {
1284         0,
1285         "multi",
1286         filter_creator
1287     };
1288 }
1289
1290
1291 /*
1292  * Local variables:
1293  * c-basic-offset: 4
1294  * c-file-style: "Stroustrup"
1295  * indent-tabs-mode: nil
1296  * End:
1297  * vim: shiftwidth=4 tabstop=8 expandtab
1298  */
1299