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     int smallSetUpperBound = *req->smallSetUpperBound;
 537     int largeSetLowerBound = *req->largeSetLowerBound;
 538     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     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     int number;
 623     mp::util::piggyback(smallSetUpperBound,
 624                          largeSetLowerBound,
 625                          mediumSetPresentNumber,
 626                          result_set_size,
 627                          number);
 628     Package pp(package.session(), package.origin());
 629     if (number > 0)
 630     {
 631         pp.copy_filter(package);
 632         Z_APDU *p_apdu = zget_APDU(odr, Z_APDU_presentRequest);
 633         Z_PresentRequest *p_req = p_apdu->u.presentRequest;
 634         p_req->preferredRecordSyntax = req->preferredRecordSyntax;
 635         p_req->resultSetId = req->resultSetName;
 636         *p_req->resultSetStartPoint = 1;
 637         *p_req->numberOfRecordsRequested = number;
 638         pp.request() = p_apdu;
 639         present(pp, p_apdu);
 640
 641         if (pp.session().is_closed())
 642             package.session().close();
 643
 644         Z_GDU *gdu = pp.response().get();
 645         if (gdu && gdu->which == Z_GDU_Z3950 && gdu->u.z3950->which ==
 646             Z_APDU_presentResponse)
 647         {
 648             Z_PresentResponse *p_res = gdu->u.z3950->u.presentResponse;
 649             f_resp->records = p_res->records;
 650             *f_resp->numberOfRecordsReturned =
 651                 *p_res->numberOfRecordsReturned;
 652             *f_resp->nextResultSetPosition =
 653                 *p_res->nextResultSetPosition;
 654         }
 655         else
 656         {
 657             package.response() = pp.response();
 658             return;
 659         }
 660     }
 661     package.response() = f_apdu; // in this scope because of p
 662 }
 663
 664 void yf::Multi::Frontend::present(mp::Package &package, Z_APDU *apdu_req)
 665 {
 666     // create present request
 667     Z_PresentRequest *req = apdu_req->u.presentRequest;
 668
 669     Sets_it it;
 670     it = m_sets.find(std::string(req->resultSetId));
 671     if (it == m_sets.end())
 672     {
 673         mp::odr odr;
 674         Z_APDU *apdu =
 675             odr.create_presentResponse(
 676                 apdu_req,
 677                 YAZ_BIB1_SPECIFIED_RESULT_SET_DOES_NOT_EXIST,
 678                 req->resultSetId);
 679         package.response() = apdu;
 680         return;
 681     }
 682     std::list<Multi::FrontendSet::PresentJob> jobs;
 683     int start = *req->resultSetStartPoint;
 684     int number = *req->numberOfRecordsRequested;
 685
 686     if (m_p->m_merge_type == round_robin)
 687         it->second.round_robin(start, number, jobs);
 688     else if (m_p->m_merge_type == serve_order)
 689         it->second.serve_order(start, number, jobs);
 690
 691     if (0)
 692     {
 693         std::list<Multi::FrontendSet::PresentJob>::const_iterator jit;
 694         for (jit = jobs.begin(); jit != jobs.end(); jit++)
 695         {
 696             yaz_log(YLOG_LOG, "job pos=%d", jit->m_pos);
 697         }
 698     }
 699
 700     std::list<BackendPtr> present_backend_list;
 701
 702     std::list<BackendSet>::const_iterator bsit;
 703     bsit = it->second.m_backend_sets.begin();
 704     for (; bsit != it->second.m_backend_sets.end(); bsit++)
 705     {
 706         int start = -1;
 707         int end = -1;
 708         {
 709             std::list<Multi::FrontendSet::PresentJob>::const_iterator jit;
 710             for (jit = jobs.begin(); jit != jobs.end(); jit++)
 711             {
 712                 if (jit->m_backend == bsit->m_backend)
 713                 {
 714                     if (start == -1 || jit->m_pos < start)
 715                         start = jit->m_pos;
 716                     if (end == -1 || jit->m_pos > end)
 717                         end = jit->m_pos;
 718                 }
 719             }
 720         }
 721         if (start != -1)
 722         {
 723             std::list<Multi::FrontendSet::PresentJob>::iterator jit;
 724             for (jit = jobs.begin(); jit != jobs.end(); jit++)
 725             {
 726                 if (jit->m_backend == bsit->m_backend)
 727                 {
 728                     if (jit->m_pos >= start && jit->m_pos <= end)
 729                         jit->m_start = start;
 730                 }
 731             }
 732
 733             PackagePtr p = bsit->m_backend->m_package;
 734
 735             *req->resultSetStartPoint = start;
 736             *req->numberOfRecordsRequested = end - start + 1;
 737
 738             p->request() = apdu_req;
 739             p->copy_filter(package);
 740
 741             present_backend_list.push_back(bsit->m_backend);
 742         }
 743     }
 744     multi_move(present_backend_list);
 745
 746     // look at each response
 747     Z_Records *z_records_diag = 0;
 748
 749     std::list<BackendPtr>::const_iterator pbit = present_backend_list.begin();
 750     for (; pbit != present_backend_list.end(); pbit++)
 751     {
 752         PackagePtr p = (*pbit)->m_package;
 753
 754         if (p->session().is_closed()) // if any backend closes, close frontend
 755             package.session().close();
 756
 757         Z_GDU *gdu = p->response().get();
 758         if (gdu && gdu->which == Z_GDU_Z3950 && gdu->u.z3950->which ==
 759             Z_APDU_presentResponse)
 760         {
 761             Z_APDU *b_apdu = gdu->u.z3950;
 762             Z_PresentResponse *b_resp = b_apdu->u.presentResponse;
 763
 764             // see we get any errors (AKA diagnstics)
 765             if (b_resp->records)
 766             {
 767                 if (b_resp->records->which != Z_Records_DBOSD)
 768                     z_records_diag = b_resp->records;
 769                 // we may set this multiple times (TOO BAD!)
 770             }
 771         }
 772         else
 773         {
 774             // if any target does not return present response - return that
 775             package.response() = p->response();
 776             return;
 777         }
 778     }
 779
 780     mp::odr odr;
 781     Z_APDU *f_apdu = odr.create_presentResponse(apdu_req, 0, 0);
 782     Z_PresentResponse *f_resp = f_apdu->u.presentResponse;
 783
 784     if (z_records_diag)
 785     {
 786         f_resp->records = z_records_diag;
 787         *f_resp->presentStatus = Z_PresentStatus_failure;
 788     }
 789     else if (number < 0 || (size_t) number > jobs.size())
 790     {
 791         f_apdu =
 792             odr.create_presentResponse(
 793                 apdu_req,
 794                 YAZ_BIB1_PRESENT_REQUEST_OUT_OF_RANGE,
 795                 0);
 796     }
 797     else
 798     {
 799         f_resp->records = (Z_Records *) odr_malloc(odr, sizeof(Z_Records));
 800         Z_Records * records = f_resp->records;
 801         records->which = Z_Records_DBOSD;
 802         records->u.databaseOrSurDiagnostics =
 803             (Z_NamePlusRecordList *)
 804             odr_malloc(odr, sizeof(Z_NamePlusRecordList));
 805         Z_NamePlusRecordList *nprl = records->u.databaseOrSurDiagnostics;
 806         nprl->num_records = jobs.size();
 807         nprl->records = (Z_NamePlusRecord**)
 808             odr_malloc(odr, sizeof(Z_NamePlusRecord *) * nprl->num_records);
 809         int i = 0;
 810         std::list<Multi::FrontendSet::PresentJob>::const_iterator jit;
 811         for (jit = jobs.begin(); jit != jobs.end(); jit++, i++)
 812         {
 813             PackagePtr p = jit->m_backend->m_package;
 814
 815             Z_GDU *gdu = p->response().get();
 816             Z_APDU *b_apdu = gdu->u.z3950;
 817             Z_PresentResponse *b_resp = b_apdu->u.presentResponse;
 818
 819             nprl->records[i] = (Z_NamePlusRecord*)
 820                 odr_malloc(odr, sizeof(Z_NamePlusRecord));
 821             int inside_pos = jit->m_pos - jit->m_start;
 822             if (inside_pos >= b_resp->records->
 823                 u.databaseOrSurDiagnostics->num_records)
 824                 break;
 825             *nprl->records[i] = *b_resp->records->
 826                 u.databaseOrSurDiagnostics->records[inside_pos];
 827             nprl->records[i]->databaseName =
 828                     odr_strdup(odr, jit->m_backend->m_vhost.c_str());
 829         }
 830         nprl->num_records = i; // usually same as jobs.size();
 831         *f_resp->nextResultSetPosition = start + i;
 832         *f_resp->numberOfRecordsReturned = i;
 833     }
 834     package.response() = f_apdu;
 835 }
 836
 837 void yf::Multi::Frontend::scan1(mp::Package &package, Z_APDU *apdu_req)
 838 {
 839     if (m_backend_list.size() > 1)
 840     {
 841         mp::odr odr;
 842         Z_APDU *f_apdu =
 843             odr.create_scanResponse(
 844                 apdu_req, YAZ_BIB1_COMBI_OF_SPECIFIED_DATABASES_UNSUPP, 0);
 845         package.response() = f_apdu;
 846         return;
 847     }
 848     Z_ScanRequest *req = apdu_req->u.scanRequest;
 849
 850     int default_num_db = req->num_databaseNames;
 851     char **default_db = req->databaseNames;
 852
 853     std::list<BackendPtr>::const_iterator bit;
 854     for (bit = m_backend_list.begin(); bit != m_backend_list.end(); bit++)
 855     {
 856         PackagePtr p = (*bit)->m_package;
 857         mp::odr odr;
 858
 859         if (!mp::util::set_databases_from_zurl(odr, (*bit)->m_vhost,
 860                                                 &req->num_databaseNames,
 861                                                 &req->databaseNames))
 862         {
 863             req->num_databaseNames = default_num_db;
 864             req->databaseNames = default_db;
 865         }
 866         p->request() = apdu_req;
 867         p->copy_filter(package);
 868     }
 869     multi_move(m_backend_list);
 870
 871     for (bit = m_backend_list.begin(); bit != m_backend_list.end(); bit++)
 872     {
 873         PackagePtr p = (*bit)->m_package;
 874
 875         if (p->session().is_closed()) // if any backend closes, close frontend
 876             package.session().close();
 877
 878         Z_GDU *gdu = p->response().get();
 879         if (gdu && gdu->which == Z_GDU_Z3950 && gdu->u.z3950->which ==
 880             Z_APDU_scanResponse)
 881         {
 882             package.response() = p->response();
 883             break;
 884         }
 885         else
 886         {
 887             // if any target does not return scan response - return that
 888             package.response() = p->response();
 889             return;
 890         }
 891     }
 892 }
 893
 894 bool yf::Multi::ScanTermInfo::operator < (const ScanTermInfo &k) const
 895 {
 896     return m_norm_term < k.m_norm_term;
 897 }
 898
 899 bool yf::Multi::ScanTermInfo::operator == (const ScanTermInfo &k) const
 900 {
 901     return m_norm_term == k.m_norm_term;
 902 }
 903
 904 Z_Entry *yf::Multi::ScanTermInfo::get_entry(ODR odr)
 905 {
 906     Z_Entry *e = (Z_Entry *)odr_malloc(odr, sizeof(*e));
 907     e->which = Z_Entry_termInfo;
 908     Z_TermInfo *t;
 909     t = e->u.termInfo = (Z_TermInfo *) odr_malloc(odr, sizeof(*t));
 910     t->suggestedAttributes = 0;
 911     t->displayTerm = 0;
 912     t->alternativeTerm = 0;
 913     t->byAttributes = 0;
 914     t->otherTermInfo = 0;
 915     t->globalOccurrences = odr_intdup(odr, m_count);
 916     t->term = (Z_Term *)
 917         odr_malloc(odr, sizeof(*t->term));
 918     t->term->which = Z_Term_general;
 919     Odr_oct *o;
 920     t->term->u.general = o = (Odr_oct *)odr_malloc(odr, sizeof(Odr_oct));
 921
 922     o->len = o->size = m_norm_term.size();
 923     o->buf = (unsigned char *) odr_malloc(odr, o->len);
 924     memcpy(o->buf, m_norm_term.c_str(), o->len);
 925     return e;
 926 }
 927
 928 void yf::Multi::Frontend::relay_apdu(mp::Package &package, Z_APDU *apdu_req)
 929 {
 930     std::list<BackendPtr>::const_iterator bit;
 931     for (bit = m_backend_list.begin(); bit != m_backend_list.end(); bit++)
 932     {
 933         PackagePtr p = (*bit)->m_package;
 934         mp::odr odr;
 935
 936         p->request() = apdu_req;
 937         p->copy_filter(package);
 938     }
 939     multi_move(m_backend_list);
 940     for (bit = m_backend_list.begin(); bit != m_backend_list.end(); bit++)
 941     {
 942         PackagePtr p = (*bit)->m_package;
 943
 944         if (p->session().is_closed()) // if any backend closes, close frontend
 945             package.session().close();
 946
 947         package.response() = p->response();
 948     }
 949 }
 950
 951
 952 void yf::Multi::Frontend::scan2(mp::Package &package, Z_APDU *apdu_req)
 953 {
 954     Z_ScanRequest *req = apdu_req->u.scanRequest;
 955
 956     int default_num_db = req->num_databaseNames;
 957     char **default_db = req->databaseNames;
 958
 959     std::list<BackendPtr>::const_iterator bit;
 960     for (bit = m_backend_list.begin(); bit != m_backend_list.end(); bit++)
 961     {
 962         PackagePtr p = (*bit)->m_package;
 963         mp::odr odr;
 964
 965         if (!mp::util::set_databases_from_zurl(odr, (*bit)->m_vhost,
 966                                                 &req->num_databaseNames,
 967                                                 &req->databaseNames))
 968         {
 969             req->num_databaseNames = default_num_db;
 970             req->databaseNames = default_db;
 971         }
 972         p->request() = apdu_req;
 973         p->copy_filter(package);
 974     }
 975     multi_move(m_backend_list);
 976
 977     ScanTermInfoList entries_before;
 978     ScanTermInfoList entries_after;
 979     int no_before = 0;
 980     int no_after = 0;
 981
 982     for (bit = m_backend_list.begin(); bit != m_backend_list.end(); bit++)
 983     {
 984         PackagePtr p = (*bit)->m_package;
 985
 986         if (p->session().is_closed()) // if any backend closes, close frontend
 987             package.session().close();
 988
 989         Z_GDU *gdu = p->response().get();
 990         if (gdu && gdu->which == Z_GDU_Z3950 && gdu->u.z3950->which ==
 991             Z_APDU_scanResponse)
 992         {
 993             Z_ScanResponse *res = gdu->u.z3950->u.scanResponse;
 994
 995             if (res->entries && res->entries->nonsurrogateDiagnostics)
 996             {
 997                 // failure
 998                 mp::odr odr;
 999                 Z_APDU *f_apdu = odr.create_scanResponse(apdu_req, 1, 0);
1000                 Z_ScanResponse *f_res = f_apdu->u.scanResponse;
1001
1002                 f_res->entries->nonsurrogateDiagnostics =
1003                     res->entries->nonsurrogateDiagnostics;
1004                 f_res->entries->num_nonsurrogateDiagnostics =
1005                     res->entries->num_nonsurrogateDiagnostics;
1006
1007                 package.response() = f_apdu;
1008                 return;
1009             }
1010
1011             if (res->entries && res->entries->entries)
1012             {
1013                 Z_Entry **entries = res->entries->entries;
1014                 int num_entries = res->entries->num_entries;
1015                 int position = 1;
1016                 if (req->preferredPositionInResponse)
1017                     position = *req->preferredPositionInResponse;
1018                 if (res->positionOfTerm)
1019                     position = *res->positionOfTerm;
1020
1021                 // before
1022                 int i;
1023                 for (i = 0; i<position-1 && i<num_entries; i++)
1024                 {
1025                     Z_Entry *ent = entries[i];
1026
1027                     if (ent->which == Z_Entry_termInfo)
1028                     {
1029                         ScanTermInfo my;
1030
1031                         Odr_int *occur = ent->u.termInfo->globalOccurrences;
1032                         my.m_count = occur ? *occur : 0;
1033
1034                         if (ent->u.termInfo->term->which == Z_Term_general)
1035                         {
1036                             my.m_norm_term = std::string(
1037                                 (const char *)
1038                                 ent->u.termInfo->term->u.general->buf,
1039                                 ent->u.termInfo->term->u.general->len);
1040                         }
1041                         if (my.m_norm_term.length())
1042                         {
1043                             ScanTermInfoList::iterator it =
1044                                 entries_before.begin();
1045                             while (it != entries_before.end() && my <*it)
1046                                 it++;
1047                             if (my == *it)
1048                             {
1049                                 it->m_count += my.m_count;
1050                             }
1051                             else
1052                             {
1053                                 entries_before.insert(it, my);
1054                                 no_before++;
1055                             }
1056                         }
1057                     }
1058                 }
1059                 // after
1060                 if (position <= 0)
1061                     i = 0;
1062                 else
1063                     i = position-1;
1064                 for ( ; i<num_entries; i++)
1065                 {
1066                     Z_Entry *ent = entries[i];
1067
1068                     if (ent->which == Z_Entry_termInfo)
1069                     {
1070                         ScanTermInfo my;
1071
1072                         Odr_int *occur = ent->u.termInfo->globalOccurrences;
1073                         my.m_count = occur ? *occur : 0;
1074
1075                         if (ent->u.termInfo->term->which == Z_Term_general)
1076                         {
1077                             my.m_norm_term = std::string(
1078                                 (const char *)
1079                                 ent->u.termInfo->term->u.general->buf,
1080                                 ent->u.termInfo->term->u.general->len);
1081                         }
1082                         if (my.m_norm_term.length())
1083                         {
1084                             ScanTermInfoList::iterator it =
1085                                 entries_after.begin();
1086                             while (it != entries_after.end() && *it < my)
1087                                 it++;
1088                             if (my == *it)
1089                             {
1090                                 it->m_count += my.m_count;
1091                             }
1092                             else
1093                             {
1094                                 entries_after.insert(it, my);
1095                                 no_after++;
1096                             }
1097                         }
1098                     }
1099                 }
1100
1101             }
1102         }
1103         else
1104         {
1105             // if any target does not return scan response - return that
1106             package.response() = p->response();
1107             return;
1108         }
1109     }
1110
1111     if (false)
1112     {
1113         std::cout << "BEFORE\n";
1114         ScanTermInfoList::iterator it = entries_before.begin();
1115         for(; it != entries_before.end(); it++)
1116         {
1117             std::cout << " " << it->m_norm_term << " " << it->m_count << "\n";
1118         }
1119
1120         std::cout << "AFTER\n";
1121         it = entries_after.begin();
1122         for(; it != entries_after.end(); it++)
1123         {
1124             std::cout << " " << it->m_norm_term << " " << it->m_count << "\n";
1125         }
1126     }
1127
1128     if (false)
1129     {
1130         mp::odr odr;
1131         Z_APDU *f_apdu = odr.create_scanResponse(apdu_req, 1, "not implemented");
1132         package.response() = f_apdu;
1133     }
1134     else
1135     {
1136         mp::odr odr;
1137         Z_APDU *f_apdu = odr.create_scanResponse(apdu_req, 0, 0);
1138         Z_ScanResponse *resp = f_apdu->u.scanResponse;
1139
1140         int number_returned = *req->numberOfTermsRequested;
1141         int position_returned = *req->preferredPositionInResponse;
1142
1143         resp->entries->num_entries = number_returned;
1144         resp->entries->entries = (Z_Entry**)
1145             odr_malloc(odr, sizeof(Z_Entry*) * number_returned);
1146         int i;
1147
1148         int lbefore = entries_before.size();
1149         if (lbefore < position_returned-1)
1150             position_returned = lbefore+1;
1151
1152         ScanTermInfoList::iterator it = entries_before.begin();
1153         for (i = 0; i<position_returned-1 && it != entries_before.end(); i++, it++)
1154         {
1155             resp->entries->entries[position_returned-2-i] = it->get_entry(odr);
1156         }
1157
1158         it = entries_after.begin();
1159
1160         if (position_returned <= 0)
1161             i = 0;
1162         else
1163             i = position_returned-1;
1164         for (; i<number_returned && it != entries_after.end(); i++, it++)
1165         {
1166             resp->entries->entries[i] = it->get_entry(odr);
1167         }
1168
1169         number_returned = i;
1170
1171         resp->positionOfTerm = odr_intdup(odr, position_returned);
1172         resp->numberOfEntriesReturned = odr_intdup(odr, number_returned);
1173         resp->entries->num_entries = number_returned;
1174
1175         package.response() = f_apdu;
1176     }
1177 }
1178
1179
1180 void yf::Multi::process(mp::Package &package) const
1181 {
1182     FrontendPtr f = m_p->get_frontend(package);
1183
1184     Z_GDU *gdu = package.request().get();
1185
1186     if (gdu && gdu->which == Z_GDU_Z3950 && gdu->u.z3950->which ==
1187         Z_APDU_initRequest && !f->m_is_multi)
1188     {
1189         f->init(package, gdu);
1190     }
1191     else if (!f->m_is_multi)
1192         package.move();
1193     else if (gdu && gdu->which == Z_GDU_Z3950)
1194     {
1195         Z_APDU *apdu = gdu->u.z3950;
1196         if (apdu->which == Z_APDU_initRequest)
1197         {
1198             mp::odr odr;
1199
1200             package.response() = odr.create_close(
1201                 apdu,
1202                 Z_Close_protocolError,
1203                 "double init");
1204
1205             package.session().close();
1206         }
1207         else if (apdu->which == Z_APDU_searchRequest)
1208         {
1209             f->search(package, apdu);
1210         }
1211         else if (apdu->which == Z_APDU_presentRequest)
1212         {
1213             f->present(package, apdu);
1214         }
1215         else if (apdu->which == Z_APDU_scanRequest)
1216         {
1217             f->scan2(package, apdu);
1218         }
1219         else if (apdu->which == Z_APDU_close)
1220         {
1221             f->relay_apdu(package, apdu);
1222         }
1223         else
1224         {
1225             mp::odr odr;
1226
1227             package.response() = odr.create_close(
1228                 apdu, Z_Close_protocolError,
1229                 "unsupported APDU in filter multi");
1230
1231             package.session().close();
1232         }
1233     }
1234     m_p->release_frontend(package);
1235 }
1236
1237 void mp::filter::Multi::configure(const xmlNode * ptr, bool test_only)
1238 {
1239     for (ptr = ptr->children; ptr; ptr = ptr->next)
1240     {
1241         if (ptr->type != XML_ELEMENT_NODE)
1242             continue;
1243         if (!strcmp((const char *) ptr->name, "target"))
1244         {
1245             std::string route = mp::xml::get_route(ptr);
1246             std::string target = mp::xml::get_text(ptr);
1247             m_p->m_route_patterns.push_back(Multi::Map(target, route));
1248         }
1249         else if (!strcmp((const char *) ptr->name, "hideunavailable"))
1250         {
1251             m_p->m_hide_unavailable = true;
1252         }
1253         else if (!strcmp((const char *) ptr->name, "mergetype"))
1254         {
1255             std::string mergetype = mp::xml::get_text(ptr);
1256             if (mergetype == "roundrobin")
1257                 m_p->m_merge_type = round_robin;
1258             else if (mergetype == "serveorder")
1259                 m_p->m_merge_type = serve_order;
1260             else
1261                 throw mp::filter::FilterException
1262                     ("Bad mergetype "  + mergetype + " in multi filter");
1263
1264         }
1265         else
1266         {
1267             throw mp::filter::FilterException
1268                 ("Bad element "
1269                  + std::string((const char *) ptr->name)
1270                  + " in multi filter");
1271         }
1272     }
1273 }
1274
1275 static mp::filter::Base* filter_creator()
1276 {
1277     return new mp::filter::Multi;
1278 }
1279
1280 extern "C" {
1281     struct metaproxy_1_filter_struct metaproxy_1_filter_multi = {
1282         0,
1283         "multi",
1284         filter_creator
1285     };
1286 }
1287
1288
1289 /*
1290  * Local variables:
1291  * c-basic-offset: 4
1292  * c-file-style: "Stroustrup"
1293  * indent-tabs-mode: nil
1294  * End:
1295  * vim: shiftwidth=4 tabstop=8 expandtab
1296  */
1297