src/filter_session_shared.cpp

   1 /* This file is part of Metaproxy.
   2    Copyright (C) Index Data
   3
   4 Metaproxy is free software; you can redistribute it and/or modify it under
   5 the terms of the GNU General Public License as published by the Free
   6 Software Foundation; either version 2, or (at your option) any later
   7 version.
   8
   9 Metaproxy is distributed in the hope that it will be useful, but WITHOUT ANY
  10 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12 for more details.
  13
  14 You should have received a copy of the GNU General Public License
  15 along with this program; if not, write to the Free Software
  16 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  17 */
  18
  19 #include "config.hpp"
  20
  21 #include <metaproxy/filter.hpp>
  22 #include <metaproxy/package.hpp>
  23
  24 #include <boost/thread/mutex.hpp>
  25 #include <boost/thread/condition.hpp>
  26 #include <boost/thread/thread.hpp>
  27 #include <boost/thread/xtime.hpp>
  28 #include <boost/shared_ptr.hpp>
  29 #include <boost/format.hpp>
  30
  31 #include <metaproxy/util.hpp>
  32 #include "filter_session_shared.hpp"
  33
  34 #include <yaz/copy_types.h>
  35 #include <yaz/log.h>
  36 #include <yaz/zgdu.h>
  37 #include <yaz/otherinfo.h>
  38 #include <yaz/diagbib1.h>
  39 #include <yazpp/z-query.h>
  40 #include <yazpp/record-cache.h>
  41 #include <map>
  42 #include <iostream>
  43 #include <time.h>
  44 #include <limits.h>
  45
  46 namespace mp = metaproxy_1;
  47 namespace yf = metaproxy_1::filter;
  48
  49 namespace metaproxy_1 {
  50
  51     namespace filter {
  52         // key for session.. We'll only share sessions with same InitKey
  53         class SessionShared::InitKey {
  54         public:
  55             bool operator < (const SessionShared::InitKey &k) const;
  56             InitKey(Z_InitRequest *req);
  57             InitKey(const InitKey &);
  58             ~InitKey();
  59         private:
  60             char *m_idAuthentication_buf;
  61             int m_idAuthentication_size;
  62             char *m_otherInfo_buf;
  63             int m_otherInfo_size;
  64             ODR m_odr;
  65         };
  66         // worker thread .. for expiry of sessions
  67         class SessionShared::Worker {
  68         public:
  69             Worker(SessionShared::Rep *rep);
  70             void operator() (void);
  71         private:
  72             SessionShared::Rep *m_p;
  73         };
  74         // backend result set
  75         class SessionShared::BackendSet {
  76         public:
  77             std::string m_result_set_id;
  78             Databases m_databases;
  79             Odr_int m_result_set_size;
  80             yazpp_1::Yaz_Z_Query m_query;
  81             time_t m_time_last_use;
  82             void timestamp();
  83             yazpp_1::RecordCache m_record_cache;
  84
  85             Z_OtherInformation *additionalSearchInfoRequest;
  86             Z_OtherInformation *additionalSearchInfoResponse;
  87             NMEM mem_additionalSearchInfo;
  88             BackendSet(
  89                 const std::string &result_set_id,
  90                 const Databases &databases,
  91                 const yazpp_1::Yaz_Z_Query &query,
  92                 Z_OtherInformation *additionalSearchInfoRequest);
  93             ~BackendSet();
  94             bool search(
  95                 Package &frontend_package,
  96                 Package &search_package,
  97                 const Z_APDU *apdu_req,
  98                 const BackendInstancePtr bp,
  99                 Z_Records **z_records);
 100         };
 101         // backend connection instance
 102         class SessionShared::BackendInstance {
 103             friend class Rep;
 104             friend class BackendClass;
 105             friend class BackendSet;
 106         public:
 107             mp::Session m_session;
 108             BackendSetList m_sets;
 109             bool m_in_use;
 110             int m_sequence_this;
 111             int m_result_set_sequence;
 112             time_t m_time_last_use;
 113             mp::Package * m_close_package;
 114             ~BackendInstance();
 115             void timestamp();
 116         };
 117         // backends of some class (all with same InitKey)
 118         class SessionShared::BackendClass : boost::noncopyable {
 119             friend class Rep;
 120             friend struct Frontend;
 121             bool m_named_result_sets;
 122             BackendInstanceList m_backend_list;
 123             BackendInstancePtr create_backend(const Package &package);
 124             void remove_backend(BackendInstancePtr b);
 125             BackendInstancePtr get_backend(const Package &package);
 126             void use_backend(BackendInstancePtr b);
 127             void release_backend(BackendInstancePtr b);
 128             bool expire_instances();
 129             yazpp_1::GDU m_init_request;
 130             yazpp_1::GDU m_init_response;
 131             boost::mutex m_mutex_backend_class;
 132             boost::condition m_cond_set_ready;
 133             int m_sequence_top;
 134             time_t m_backend_set_ttl;
 135             time_t m_backend_expiry_ttl;
 136             size_t m_backend_set_max;
 137             Odr_int m_preferredMessageSize;
 138             Odr_int m_maximumRecordSize;
 139             int m_no_failed;
 140             int m_no_succeeded;
 141             int m_no_init;
 142         public:
 143             BackendClass(const yazpp_1::GDU &init_request,
 144                          int resultset_ttl,
 145                          int resultset_max,
 146                          int session_ttl,
 147                          Odr_int preferredRecordSize,
 148                          Odr_int maximumRecordSize);
 149             ~BackendClass();
 150         };
 151         // frontend result set
 152         class SessionShared::FrontendSet {
 153             Databases m_databases;
 154             yazpp_1::Yaz_Z_Query m_query;
 155         public:
 156             const Databases &get_databases();
 157             const yazpp_1::Yaz_Z_Query &get_query();
 158             FrontendSet(
 159                 const Databases &databases,
 160                 const yazpp_1::Yaz_Z_Query &query);
 161             FrontendSet();
 162         };
 163         // frontend session
 164         struct SessionShared::Frontend {
 165             Frontend(Rep *rep);
 166             ~Frontend();
 167             bool m_is_virtual;
 168             bool m_in_use;
 169             Z_Options m_init_options;
 170             void search(Package &package, Z_APDU *apdu);
 171             void present(Package &package, Z_APDU *apdu);
 172             void scan(Package &package, Z_APDU *apdu);
 173
 174             int result_set_ref(ODR o,
 175                                const Databases &databases,
 176                                Z_RPNStructure *s, std::string &rset);
 177             void get_set(mp::Package &package,
 178                          const Z_APDU *apdu_req,
 179                          const Databases &databases,
 180                          yazpp_1::Yaz_Z_Query &query,
 181                          BackendInstancePtr &found_backend,
 182                          BackendSetPtr &found_set);
 183             void override_set(BackendInstancePtr &found_backend,
 184                               std::string &result_set_id,
 185                               const Databases &databases,
 186                               bool out_of_sessions);
 187
 188             Rep *m_p;
 189             BackendClassPtr m_backend_class;
 190             FrontendSets m_frontend_sets;
 191         };
 192         // representation
 193         class SessionShared::Rep {
 194             friend class SessionShared;
 195             friend struct Frontend;
 196
 197             FrontendPtr get_frontend(Package &package);
 198             void release_frontend(Package &package);
 199             Rep();
 200         public:
 201             ~Rep();
 202             void expire();
 203         private:
 204             void expire_classes();
 205             void stat();
 206             void init(Package &package, const Z_GDU *gdu,
 207                       FrontendPtr frontend);
 208             void start();
 209             boost::mutex m_mutex;
 210             boost::condition m_cond_session_ready;
 211             boost::condition m_cond_expire_ready;
 212             std::map<mp::Session, FrontendPtr> m_clients;
 213
 214             BackendClassMap m_backend_map;
 215             boost::mutex m_mutex_backend_map;
 216             boost::thread_group m_thrds;
 217             int m_resultset_ttl;
 218             int m_resultset_max;
 219             int m_session_ttl;
 220             bool m_optimize_search;
 221             bool m_restart;
 222             int m_session_max;
 223             Odr_int m_preferredMessageSize;
 224             Odr_int m_maximumRecordSize;
 225             bool close_down;
 226         };
 227     }
 228 }
 229
 230 yf::SessionShared::FrontendSet::FrontendSet(
 231     const Databases &databases,
 232     const yazpp_1::Yaz_Z_Query &query)
 233     : m_databases(databases), m_query(query)
 234 {
 235 }
 236
 237 const yf::SessionShared::Databases &
 238 yf::SessionShared::FrontendSet::get_databases()
 239 {
 240     return m_databases;
 241 }
 242
 243 const yazpp_1::Yaz_Z_Query& yf::SessionShared::FrontendSet::get_query()
 244 {
 245     return m_query;
 246 }
 247
 248 yf::SessionShared::InitKey::InitKey(const InitKey &k)
 249 {
 250     m_odr = odr_createmem(ODR_ENCODE);
 251
 252     m_idAuthentication_size =  k.m_idAuthentication_size;
 253     m_idAuthentication_buf = (char*)odr_malloc(m_odr, m_idAuthentication_size);
 254     memcpy(m_idAuthentication_buf, k.m_idAuthentication_buf,
 255            m_idAuthentication_size);
 256
 257     m_otherInfo_size =  k.m_otherInfo_size;
 258     m_otherInfo_buf = (char*)odr_malloc(m_odr, m_otherInfo_size);
 259     memcpy(m_otherInfo_buf, k.m_otherInfo_buf,
 260            m_otherInfo_size);
 261 }
 262
 263 yf::SessionShared::InitKey::InitKey(Z_InitRequest *req)
 264 {
 265     m_odr = odr_createmem(ODR_ENCODE);
 266
 267     Z_IdAuthentication *t = req->idAuthentication;
 268     z_IdAuthentication(m_odr, &t, 1, 0);
 269     m_idAuthentication_buf =
 270         odr_getbuf(m_odr, &m_idAuthentication_size, 0);
 271
 272     Z_OtherInformation *o = req->otherInfo;
 273     z_OtherInformation(m_odr, &o, 1, 0);
 274     m_otherInfo_buf = odr_getbuf(m_odr, &m_otherInfo_size, 0);
 275 }
 276
 277 yf::SessionShared::InitKey::~InitKey()
 278 {
 279     odr_destroy(m_odr);
 280 }
 281
 282 bool yf::SessionShared::InitKey::operator < (const SessionShared::InitKey &k)
 283     const
 284 {
 285     int c;
 286     c = mp::util::memcmp2(
 287         (void*) m_idAuthentication_buf, m_idAuthentication_size,
 288         (void*) k.m_idAuthentication_buf, k.m_idAuthentication_size);
 289     if (c < 0)
 290         return true;
 291     else if (c > 0)
 292         return false;
 293
 294     c = mp::util::memcmp2((void*) m_otherInfo_buf, m_otherInfo_size,
 295                           (void*) k.m_otherInfo_buf, k.m_otherInfo_size);
 296     if (c < 0)
 297         return true;
 298     else if (c > 0)
 299         return false;
 300     return false;
 301 }
 302
 303 void yf::SessionShared::BackendClass::release_backend(BackendInstancePtr b)
 304 {
 305     boost::mutex::scoped_lock lock(m_mutex_backend_class);
 306     m_cond_set_ready.notify_all();
 307     b->m_in_use = false;
 308 }
 309
 310
 311 void yf::SessionShared::BackendClass::remove_backend(BackendInstancePtr b)
 312 {
 313     {
 314         boost::mutex::scoped_lock lock(m_mutex_backend_class);
 315         BackendInstanceList::iterator it = m_backend_list.begin();
 316         for (;;)
 317         {
 318             if (it == m_backend_list.end())
 319                 return;
 320             if (*it == b)
 321             {
 322                 it = m_backend_list.erase(it);
 323                 break;
 324             }
 325             it++;
 326         }
 327     }
 328     mp::odr odr;
 329     b->m_close_package->response() = odr.create_close(
 330         0, Z_Close_lackOfActivity, 0);
 331     b->m_close_package->session().close();
 332     b->m_close_package->move();
 333 }
 334
 335
 336 yf::SessionShared::BackendInstancePtr
 337 yf::SessionShared::BackendClass::get_backend(
 338     const mp::Package &frontend_package)
 339 {
 340     {
 341         boost::mutex::scoped_lock lock(m_mutex_backend_class);
 342
 343         BackendInstanceList::const_iterator it = m_backend_list.begin();
 344
 345         BackendInstancePtr backend1; // null
 346
 347         for (; it != m_backend_list.end(); it++)
 348         {
 349             if (!(*it)->m_in_use)
 350             {
 351                 if (!backend1
 352                     || (*it)->m_sequence_this < backend1->m_sequence_this)
 353                     backend1 = *it;
 354             }
 355         }
 356         if (backend1)
 357         {
 358             use_backend(backend1);
 359             return backend1;
 360         }
 361     }
 362     return create_backend(frontend_package);
 363 }
 364
 365 void yf::SessionShared::BackendClass::use_backend(BackendInstancePtr backend)
 366 {
 367     backend->m_in_use = true;
 368     backend->m_sequence_this = m_sequence_top++;
 369 }
 370
 371 void yf::SessionShared::BackendInstance::timestamp()
 372 {
 373     assert(m_in_use);
 374     time(&m_time_last_use);
 375 }
 376
 377 yf::SessionShared::BackendInstance::~BackendInstance()
 378 {
 379     if (m_close_package)
 380     {
 381         mp::odr odr;
 382         m_close_package->response() = odr.create_close(
 383             0, Z_Close_lackOfActivity, 0);
 384         m_close_package->session().close();
 385         m_close_package->move();
 386     }
 387     delete m_close_package;
 388 }
 389
 390 yf::SessionShared::BackendInstancePtr yf::SessionShared::BackendClass::create_backend(
 391     const mp::Package &frontend_package)
 392 {
 393     BackendInstancePtr null;
 394     {
 395         boost::mutex::scoped_lock lock(m_mutex_backend_class);
 396         if (m_no_failed && !m_no_succeeded)
 397         {
 398             m_no_failed++;
 399             return null;
 400         }
 401     }
 402     BackendInstancePtr bp(new BackendInstance);
 403     bp->m_close_package =
 404         new mp::Package(bp->m_session, frontend_package.origin());
 405     bp->m_close_package->copy_filter(frontend_package);
 406
 407     Package init_package(bp->m_session, frontend_package.origin());
 408
 409     init_package.copy_filter(frontend_package);
 410
 411     yazpp_1::GDU actual_init_request = m_init_request;
 412     Z_GDU *init_pdu = actual_init_request.get();
 413
 414     assert(init_pdu->which == Z_GDU_Z3950);
 415     assert(init_pdu->u.z3950->which == Z_APDU_initRequest);
 416
 417     Z_InitRequest *req = init_pdu->u.z3950->u.initRequest;
 418     ODR_MASK_ZERO(req->options);
 419
 420     ODR_MASK_SET(req->options, Z_Options_search);
 421     ODR_MASK_SET(req->options, Z_Options_present);
 422     ODR_MASK_SET(req->options, Z_Options_namedResultSets);
 423     ODR_MASK_SET(req->options, Z_Options_scan);
 424
 425     ODR_MASK_SET(req->protocolVersion, Z_ProtocolVersion_1);
 426     ODR_MASK_SET(req->protocolVersion, Z_ProtocolVersion_2);
 427     ODR_MASK_SET(req->protocolVersion, Z_ProtocolVersion_3);
 428
 429     if (m_preferredMessageSize)
 430         *req->preferredMessageSize = m_preferredMessageSize;
 431     if (m_maximumRecordSize)
 432         *req->maximumRecordSize = m_maximumRecordSize;
 433
 434     init_package.request() = init_pdu;
 435
 436     {
 437         boost::mutex::scoped_lock lock(m_mutex_backend_class);
 438         m_no_init++;
 439     }
 440
 441     init_package.move();
 442
 443     boost::mutex::scoped_lock lock(m_mutex_backend_class);
 444
 445     m_named_result_sets = false;
 446     Z_GDU *gdu = init_package.response().get();
 447
 448     if (gdu && gdu->which == Z_GDU_Z3950
 449         && gdu->u.z3950->which == Z_APDU_initResponse)
 450     {
 451         Z_InitResponse *res = gdu->u.z3950->u.initResponse;
 452         m_init_response = gdu->u.z3950;
 453         if (ODR_MASK_GET(res->options, Z_Options_namedResultSets))
 454         {
 455             m_named_result_sets = true;
 456         }
 457         if (*gdu->u.z3950->u.initResponse->result
 458             && !init_package.session().is_closed())
 459         {
 460             bp->m_in_use = true;
 461             time(&bp->m_time_last_use);
 462             bp->m_sequence_this = 0;
 463             bp->m_result_set_sequence = 0;
 464             m_backend_list.push_back(bp);
 465             m_no_succeeded++;
 466             return bp;
 467         }
 468     }
 469     else
 470     {
 471         yazpp_1::GDU empty_gdu;
 472         m_init_response = empty_gdu;
 473     }
 474
 475     if (!init_package.session().is_closed())
 476     {
 477         init_package.copy_filter(frontend_package);
 478         init_package.session().close();
 479         init_package.move();
 480     }
 481     m_no_failed++;
 482     return null;
 483 }
 484
 485
 486 yf::SessionShared::BackendClass::BackendClass(const yazpp_1::GDU &init_request,
 487                                               int resultset_ttl,
 488                                               int resultset_max,
 489                                               int session_ttl,
 490                                               Odr_int preferredMessageSize,
 491                                               Odr_int maximumRecordSize)
 492     : m_named_result_sets(false), m_init_request(init_request),
 493       m_sequence_top(0), m_backend_set_ttl(resultset_ttl),
 494       m_backend_expiry_ttl(session_ttl), m_backend_set_max(resultset_max),
 495       m_preferredMessageSize(preferredMessageSize),
 496       m_maximumRecordSize(maximumRecordSize),
 497       m_no_failed(0), m_no_succeeded(0), m_no_init(0)
 498 {}
 499
 500 yf::SessionShared::BackendClass::~BackendClass()
 501 {}
 502
 503 void yf::SessionShared::Rep::stat()
 504 {
 505     int no_classes = 0;
 506     int no_instances = 0;
 507     BackendClassMap::const_iterator it;
 508     {
 509         boost::mutex::scoped_lock lock(m_mutex_backend_map);
 510         for (it = m_backend_map.begin(); it != m_backend_map.end(); it++)
 511         {
 512             BackendClassPtr bc = it->second;
 513             no_classes++;
 514             BackendInstanceList::iterator bit = bc->m_backend_list.begin();
 515             for (; bit != bc->m_backend_list.end(); bit++)
 516                 no_instances++;
 517         }
 518     }
 519 }
 520
 521 void yf::SessionShared::Rep::init(mp::Package &package, const Z_GDU *gdu,
 522                                   FrontendPtr frontend)
 523 {
 524     Z_InitRequest *req = gdu->u.z3950->u.initRequest;
 525
 526     frontend->m_is_virtual = true;
 527     frontend->m_init_options = *req->options;
 528     InitKey k(req);
 529     {
 530         boost::mutex::scoped_lock lock(m_mutex_backend_map);
 531         BackendClassMap::const_iterator it;
 532         it = m_backend_map.find(k);
 533         if (it == m_backend_map.end())
 534         {
 535             BackendClassPtr b(new BackendClass(gdu->u.z3950,
 536                                                m_resultset_ttl,
 537                                                m_resultset_max,
 538                                                m_session_ttl,
 539                                                m_preferredMessageSize,
 540                                                m_maximumRecordSize));
 541             m_backend_map[k] = b;
 542             frontend->m_backend_class = b;
 543         }
 544         else
 545         {
 546             frontend->m_backend_class = it->second;
 547         }
 548     }
 549     BackendClassPtr bc = frontend->m_backend_class;
 550     mp::odr odr;
 551
 552     // we only need to get init response from "first" target in
 553     // backend class - the assumption being that init response is
 554     // same for all
 555     bool create_first_one = false;
 556     {
 557         boost::mutex::scoped_lock lock(bc->m_mutex_backend_class);
 558         if (!bc->m_no_failed && !bc->m_no_succeeded && !bc->m_no_init)
 559             create_first_one = true;
 560         else
 561         {
 562             // first for first one to finish
 563             while (!bc->m_no_failed && !bc->m_no_succeeded && bc->m_no_init)
 564             {
 565                 bc->m_cond_set_ready.wait(lock);
 566             }
 567         }
 568     }
 569     if (create_first_one)
 570     {
 571         BackendInstancePtr backend = bc->create_backend(package);
 572         if (backend)
 573             bc->release_backend(backend);
 574     }
 575     yazpp_1::GDU init_response;
 576     {
 577         boost::mutex::scoped_lock lock(bc->m_mutex_backend_class);
 578
 579         init_response = bc->m_init_response;
 580     }
 581
 582     if (init_response.get())
 583     {
 584         Z_GDU *response_gdu = init_response.get();
 585         mp::util::transfer_referenceId(odr, gdu->u.z3950,
 586                                        response_gdu->u.z3950);
 587         Z_InitResponse *init_res = response_gdu->u.z3950->u.initResponse;
 588         Z_Options *server_options = init_res->options;
 589         Z_Options *client_options = &frontend->m_init_options;
 590         int i;
 591         for (i = 0; i < 30; i++)
 592             if (!ODR_MASK_GET(client_options, i))
 593                 ODR_MASK_CLEAR(server_options, i);
 594
 595         if (!m_preferredMessageSize ||
 596             *init_res->preferredMessageSize > *req->preferredMessageSize)
 597             *init_res->preferredMessageSize = *req->preferredMessageSize;
 598
 599         if (!m_maximumRecordSize ||
 600             *init_res->maximumRecordSize > *req->maximumRecordSize)
 601             *init_res->maximumRecordSize = *req->maximumRecordSize;
 602
 603         package.response() = init_response;
 604         if (!*response_gdu->u.z3950->u.initResponse->result)
 605             package.session().close();
 606     }
 607     else
 608     {
 609         Z_APDU *apdu =
 610             odr.create_initResponse(
 611                 gdu->u.z3950, YAZ_BIB1_TEMPORARY_SYSTEM_ERROR,
 612                 "session_shared: target closed connection during init");
 613         *apdu->u.initResponse->result = 0;
 614         package.response() = apdu;
 615         package.session().close();
 616     }
 617 }
 618
 619 void yf::SessionShared::BackendSet::timestamp()
 620 {
 621     time(&m_time_last_use);
 622 }
 623
 624 yf::SessionShared::BackendSet::BackendSet(
 625     const std::string &result_set_id,
 626     const Databases &databases,
 627     const yazpp_1::Yaz_Z_Query &query,
 628     Z_OtherInformation *additionalSearchInfo) :
 629     m_result_set_id(result_set_id),
 630     m_databases(databases), m_result_set_size(0), m_query(query)
 631 {
 632     timestamp();
 633     mem_additionalSearchInfo = nmem_create();
 634     additionalSearchInfoResponse = 0;
 635     additionalSearchInfoRequest =
 636         yaz_clone_z_OtherInformation(additionalSearchInfo,
 637                                      mem_additionalSearchInfo);
 638 }
 639
 640 yf::SessionShared::BackendSet::~BackendSet()
 641 {
 642     nmem_destroy(mem_additionalSearchInfo);
 643 }
 644
 645 static int get_diagnostic(Z_DefaultDiagFormat *r)
 646 {
 647     return *r->condition;
 648 }
 649
 650 bool yf::SessionShared::BackendSet::search(
 651     mp::Package &frontend_package,
 652     mp::Package &search_package,
 653     const Z_APDU *frontend_apdu,
 654     const BackendInstancePtr bp,
 655     Z_Records **z_records)
 656 {
 657     mp::odr odr;
 658     Z_APDU *apdu_req = zget_APDU(odr, Z_APDU_searchRequest);
 659     Z_SearchRequest *req = apdu_req->u.searchRequest;
 660
 661     req->additionalSearchInfo = additionalSearchInfoRequest;
 662     req->resultSetName = odr_strdup(odr, m_result_set_id.c_str());
 663     req->query = m_query.get_Z_Query();
 664
 665     req->num_databaseNames = m_databases.size();
 666     req->databaseNames = (char**)
 667         odr_malloc(odr, req->num_databaseNames * sizeof(char *));
 668     Databases::const_iterator it = m_databases.begin();
 669     size_t i = 0;
 670     for (; it != m_databases.end(); it++)
 671         req->databaseNames[i++] = odr_strdup(odr, it->c_str());
 672
 673     if (frontend_apdu->which == Z_APDU_searchRequest)
 674         req->preferredRecordSyntax =
 675             frontend_apdu->u.searchRequest->preferredRecordSyntax;
 676
 677     search_package.request() = apdu_req;
 678
 679     search_package.move();
 680
 681     Z_GDU *gdu = search_package.response().get();
 682     if (!search_package.session().is_closed()
 683         && gdu && gdu->which == Z_GDU_Z3950
 684         && gdu->u.z3950->which == Z_APDU_searchResponse)
 685     {
 686         Z_SearchResponse *b_resp = gdu->u.z3950->u.searchResponse;
 687         *z_records = b_resp->records;
 688         m_result_set_size = *b_resp->resultCount;
 689
 690         additionalSearchInfoResponse = yaz_clone_z_OtherInformation(
 691             b_resp->additionalSearchInfo, mem_additionalSearchInfo);
 692         return true;
 693     }
 694     Z_APDU *f_apdu = 0;
 695     const char *addinfo = "session_shared: "
 696         "target closed connection during search";
 697     if (frontend_apdu->which == Z_APDU_searchRequest)
 698         f_apdu = odr.create_searchResponse(
 699             frontend_apdu, YAZ_BIB1_TEMPORARY_SYSTEM_ERROR, addinfo);
 700     else if (frontend_apdu->which == Z_APDU_presentRequest)
 701         f_apdu = odr.create_presentResponse(
 702             frontend_apdu, YAZ_BIB1_TEMPORARY_SYSTEM_ERROR, addinfo);
 703     else
 704         f_apdu = odr.create_close(
 705             frontend_apdu, YAZ_BIB1_TEMPORARY_SYSTEM_ERROR, addinfo);
 706     frontend_package.response() = f_apdu;
 707     return false;
 708 }
 709
 710 void yf::SessionShared::Frontend::override_set(
 711     BackendInstancePtr &found_backend,
 712     std::string &result_set_id,
 713     const Databases &databases,
 714     bool out_of_sessions)
 715 {
 716     BackendClassPtr bc = m_backend_class;
 717     BackendInstanceList::const_iterator it = bc->m_backend_list.begin();
 718     time_t now;
 719     time(&now);
 720
 721     size_t max_sets = bc->m_named_result_sets ? bc->m_backend_set_max : 1;
 722     for (; it != bc->m_backend_list.end(); it++)
 723     {
 724         if (!(*it)->m_in_use)
 725         {
 726             BackendSetList::iterator set_it = (*it)->m_sets.begin();
 727             for (; set_it != (*it)->m_sets.end(); set_it++)
 728             {
 729                 if ((max_sets > 1 || (*set_it)->m_databases == databases)
 730                     &&
 731                     (out_of_sessions ||
 732                      now < (*set_it)->m_time_last_use ||
 733                      now - (*set_it)->m_time_last_use >= bc->m_backend_set_ttl))
 734                 {
 735                     found_backend = *it;
 736                     result_set_id = (*set_it)->m_result_set_id;
 737                     found_backend->m_sets.erase(set_it);
 738                     return;
 739                 }
 740             }
 741         }
 742     }
 743     for (it = bc->m_backend_list.begin(); it != bc->m_backend_list.end(); it++)
 744     {
 745         if (!(*it)->m_in_use && (*it)->m_sets.size() < max_sets)
 746         {
 747             found_backend = *it;
 748             if (bc->m_named_result_sets)
 749             {
 750                 result_set_id = boost::io::str(
 751                     boost::format("%1%") %
 752                     found_backend->m_result_set_sequence);
 753                 found_backend->m_result_set_sequence++;
 754             }
 755             else
 756                 result_set_id = "default";
 757             return;
 758         }
 759     }
 760 }
 761
 762 void yf::SessionShared::Frontend::get_set(mp::Package &package,
 763                                           const Z_APDU *apdu_req,
 764                                           const Databases &databases,
 765                                           yazpp_1::Yaz_Z_Query &query,
 766                                           BackendInstancePtr &found_backend,
 767                                           BackendSetPtr &found_set)
 768 {
 769     bool session_restarted = false;
 770     Z_OtherInformation *additionalSearchInfo = 0;
 771
 772     if (apdu_req->which == Z_APDU_searchRequest)
 773         additionalSearchInfo = apdu_req->u.searchRequest->additionalSearchInfo;
 774
 775 restart:
 776     std::string result_set_id;
 777     bool out_of_sessions = false;
 778     BackendClassPtr bc = m_backend_class;
 779     {
 780         boost::mutex::scoped_lock lock(bc->m_mutex_backend_class);
 781
 782         if ((int) bc->m_backend_list.size() >= m_p->m_session_max)
 783             out_of_sessions = true;
 784
 785         if (m_p->m_optimize_search)
 786         {
 787             // look at each backend and see if we have a similar search
 788             BackendInstanceList::const_iterator it = bc->m_backend_list.begin();
 789             while (it != bc->m_backend_list.end())
 790             {
 791                 bool restart = false;
 792                 BackendSetList::const_iterator set_it = (*it)->m_sets.begin();
 793                 for (; set_it != (*it)->m_sets.end(); set_it++)
 794                 {
 795                     // for real present request we don't care
 796                     // if additionalSearchInfo matches: same records
 797                     if ((*set_it)->m_databases == databases
 798                         && query.match(&(*set_it)->m_query)
 799                         && (apdu_req->which != Z_APDU_searchRequest ||
 800                             yaz_compare_z_OtherInformation(
 801                                 additionalSearchInfo,
 802                                 (*set_it)->additionalSearchInfoRequest)))
 803                     {
 804                         if ((*it)->m_in_use)
 805                         {
 806                             bc->m_cond_set_ready.wait(lock);
 807                             restart = true;
 808                             break;
 809                         }
 810                         else
 811                         {
 812                             found_set = *set_it;
 813                             found_backend = *it;
 814                             bc->use_backend(found_backend);
 815                             // found matching set. No need to search again
 816                             return;
 817                         }
 818                     }
 819                 }
 820                 if (restart)
 821                     it = bc->m_backend_list.begin();
 822                 else
 823                     it++;
 824             }
 825         }
 826         override_set(found_backend, result_set_id, databases, out_of_sessions);
 827         if (found_backend)
 828             bc->use_backend(found_backend);
 829     }
 830     if (!found_backend)
 831     {
 832         // create a new backend set (and new set) if we're not out of sessions
 833         if (!out_of_sessions)
 834             found_backend = bc->create_backend(package);
 835
 836         if (!found_backend)
 837         {
 838             Z_APDU *f_apdu = 0;
 839             mp::odr odr;
 840             const char *addinfo = 0;
 841
 842             if (out_of_sessions)
 843                 addinfo = "session_shared: all sessions in use";
 844             else
 845                 addinfo = "session_shared: could not create backend";
 846             if (apdu_req->which == Z_APDU_searchRequest)
 847             {
 848                 f_apdu = odr.create_searchResponse(
 849                     apdu_req, YAZ_BIB1_TEMPORARY_SYSTEM_ERROR, addinfo);
 850             }
 851             else if (apdu_req->which == Z_APDU_presentRequest)
 852             {
 853                 f_apdu = odr.create_presentResponse(
 854                     apdu_req, YAZ_BIB1_TEMPORARY_SYSTEM_ERROR, addinfo);
 855             }
 856             else
 857             {
 858                 f_apdu = odr.create_close(
 859                     apdu_req, YAZ_BIB1_TEMPORARY_SYSTEM_ERROR, addinfo);
 860             }
 861             package.response() = f_apdu;
 862             return;
 863         }
 864         if (bc->m_named_result_sets)
 865         {
 866             result_set_id = boost::io::str(
 867                 boost::format("%1%") % found_backend->m_result_set_sequence);
 868             found_backend->m_result_set_sequence++;
 869         }
 870         else
 871             result_set_id = "default";
 872     }
 873     found_backend->timestamp();
 874
 875     // we must search ...
 876     BackendSetPtr new_set(new BackendSet(result_set_id,
 877                                          databases, query,
 878                                          additionalSearchInfo));
 879
 880     found_set = new_set;
 881     found_set->timestamp();
 882     found_backend->m_sets.push_back(found_set);
 883
 884     Z_Records *z_records = 0;
 885
 886     Package search_package(found_backend->m_session, package.origin());
 887     search_package.copy_filter(package);
 888
 889     if (!new_set->search(package, search_package,
 890                          apdu_req, found_backend, &z_records))
 891     {
 892         bc->remove_backend(found_backend);
 893         return; // search error
 894     }
 895
 896     if (z_records)
 897     {
 898         int condition = 0;
 899         if (z_records->which == Z_Records_NSD)
 900         {
 901             condition =
 902                 get_diagnostic(z_records->u.nonSurrogateDiagnostic);
 903         }
 904         else if (z_records->which == Z_Records_multipleNSD)
 905         {
 906             if (z_records->u.multipleNonSurDiagnostics->num_diagRecs >= 1
 907                 &&
 908
 909                 z_records->u.multipleNonSurDiagnostics->diagRecs[0]->which ==
 910                 Z_DiagRec_defaultFormat)
 911             {
 912                 condition = get_diagnostic(
 913                     z_records->u.multipleNonSurDiagnostics->diagRecs[0]->u.defaultFormat);
 914
 915             }
 916         }
 917         if (m_p->m_restart && !session_restarted &&
 918             condition == YAZ_BIB1_TEMPORARY_SYSTEM_ERROR)
 919         {
 920             package.log("session_shared", YLOG_LOG, "restart");
 921             bc->remove_backend(found_backend);
 922             session_restarted = true;
 923             found_backend.reset();
 924             goto restart;
 925
 926         }
 927
 928         if (condition)
 929         {
 930             mp::odr odr;
 931             if (apdu_req->which == Z_APDU_searchRequest)
 932             {
 933                 Z_APDU *f_apdu = odr.create_searchResponse(apdu_req,
 934                                                            0, 0);
 935                 Z_SearchResponse *f_resp = f_apdu->u.searchResponse;
 936                 *f_resp->searchStatus = Z_SearchResponse_none;
 937                 f_resp->records = z_records;
 938                 package.response() = f_apdu;
 939             }
 940             if (apdu_req->which == Z_APDU_presentRequest)
 941             {
 942                 Z_APDU *f_apdu = odr.create_presentResponse(apdu_req,
 943                                                             0, 0);
 944                 Z_PresentResponse *f_resp = f_apdu->u.presentResponse;
 945                 f_resp->records = z_records;
 946                 package.response() = f_apdu;
 947             }
 948             bc->release_backend(found_backend);
 949             return; // search error
 950         }
 951     }
 952     if (m_p->m_restart && !session_restarted && new_set->m_result_set_size < 0)
 953     {
 954         package.log("session_shared", YLOG_LOG, "restart");
 955         bc->remove_backend(found_backend);
 956         session_restarted = true;
 957         found_backend.reset();
 958         goto restart;
 959     }
 960
 961 #if 0
 962     found_set = new_set;
 963     found_set->timestamp();
 964     found_backend->m_sets.push_back(found_set);
 965 #endif
 966 }
 967
 968 int yf::SessionShared::Frontend::result_set_ref(ODR o,
 969                                                 const Databases &databases,
 970                                                 Z_RPNStructure *s,
 971                                                 std::string &rset)
 972 {
 973     int ret = 0;
 974     switch (s->which)
 975     {
 976     case Z_RPNStructure_simple:
 977         if (s->u.simple->which == Z_Operand_resultSetId)
 978         {
 979             const char *id = s->u.simple->u.resultSetId;
 980             rset = id;
 981
 982             FrontendSets::iterator fset_it = m_frontend_sets.find(id);
 983             if (fset_it == m_frontend_sets.end())
 984             {
 985                 ret = YAZ_BIB1_SPECIFIED_RESULT_SET_DOES_NOT_EXIST;
 986             }
 987             else if (fset_it->second->get_databases() != databases)
 988             {
 989                 ret = YAZ_BIB1_SPECIFIED_RESULT_SET_DOES_NOT_EXIST;
 990             }
 991             else
 992             {
 993                 yazpp_1::Yaz_Z_Query query = fset_it->second->get_query();
 994                 Z_Query *q = yaz_copy_Z_Query(query.get_Z_Query(), o);
 995                 if (q->which == Z_Query_type_1 || q->which == Z_Query_type_101)
 996                 {
 997                     s->which = q->u.type_1->RPNStructure->which;
 998                     s->u.simple = q->u.type_1->RPNStructure->u.simple;
 999                 }
1000                 else
1001                 {
1002                     ret = YAZ_BIB1_SPECIFIED_RESULT_SET_DOES_NOT_EXIST;
1003                 }
1004             }
1005         }
1006         break;
1007     case Z_RPNStructure_complex:
1008         ret = result_set_ref(o, databases, s->u.complex->s1, rset);
1009         if (!ret)
1010             ret = result_set_ref(o, databases, s->u.complex->s2, rset);
1011         break;
1012     }
1013     return ret;
1014 }
1015
1016 void yf::SessionShared::Frontend::search(mp::Package &package,
1017                                          Z_APDU *apdu_req)
1018 {
1019     Z_SearchRequest *req = apdu_req->u.searchRequest;
1020     FrontendSets::iterator fset_it =
1021         m_frontend_sets.find(req->resultSetName);
1022     if (fset_it != m_frontend_sets.end())
1023     {
1024         // result set already exist
1025         // if replace indicator is off: we return diagnostic if
1026         // result set already exist.
1027         if (*req->replaceIndicator == 0)
1028         {
1029             mp::odr odr;
1030             Z_APDU *apdu =
1031                 odr.create_searchResponse(
1032                     apdu_req,
1033                     YAZ_BIB1_RESULT_SET_EXISTS_AND_REPLACE_INDICATOR_OFF,
1034                     0);
1035             package.response() = apdu;
1036             return;
1037         }
1038         m_frontend_sets.erase(fset_it);
1039     }
1040
1041     Databases databases;
1042     int i;
1043     for (i = 0; i < req->num_databaseNames; i++)
1044         databases.push_back(req->databaseNames[i]);
1045
1046
1047     yazpp_1::Yaz_Z_Query query;
1048     query.set_Z_Query(req->query);
1049
1050     Z_Query *q = query.get_Z_Query();
1051     if (q->which == Z_Query_type_1 || q->which == Z_Query_type_101)
1052     {
1053         mp::odr odr;
1054         std::string rset;
1055         int diag = result_set_ref(odr, databases, q->u.type_1->RPNStructure,
1056                                   rset);
1057         if (diag)
1058         {
1059             Z_APDU *apdu =
1060                 odr.create_searchResponse(
1061                     apdu_req,
1062                     diag,
1063                     rset.c_str());
1064             package.response() = apdu;
1065             return;
1066         }
1067         query.set_Z_Query(q);
1068     }
1069
1070     BackendSetPtr found_set; // null
1071     BackendInstancePtr found_backend; // null
1072
1073     get_set(package, apdu_req, databases, query, found_backend, found_set);
1074     if (!found_set)
1075         return;
1076
1077     mp::odr odr;
1078     Z_APDU *f_apdu = odr.create_searchResponse(apdu_req, 0, 0);
1079     Z_SearchResponse *f_resp = f_apdu->u.searchResponse;
1080     *f_resp->resultCount = found_set->m_result_set_size;
1081     f_resp->additionalSearchInfo = found_set->additionalSearchInfoResponse;
1082     package.response() = f_apdu;
1083
1084     FrontendSetPtr fset(new FrontendSet(databases, query));
1085     m_frontend_sets[req->resultSetName] = fset;
1086
1087     m_backend_class->release_backend(found_backend);
1088 }
1089
1090 void yf::SessionShared::Frontend::present(mp::Package &package,
1091                                           Z_APDU *apdu_req)
1092 {
1093     mp::odr odr;
1094     Z_PresentRequest *req = apdu_req->u.presentRequest;
1095
1096     FrontendSets::iterator fset_it =
1097         m_frontend_sets.find(req->resultSetId);
1098
1099     if (fset_it == m_frontend_sets.end())
1100     {
1101         Z_APDU *apdu =
1102             odr.create_presentResponse(
1103                 apdu_req,
1104                 YAZ_BIB1_SPECIFIED_RESULT_SET_DOES_NOT_EXIST,
1105                 req->resultSetId);
1106         package.response() = apdu;
1107         return;
1108     }
1109     FrontendSetPtr fset = fset_it->second;
1110
1111     Databases databases = fset->get_databases();
1112     yazpp_1::Yaz_Z_Query query = fset->get_query();
1113
1114     BackendClassPtr bc = m_backend_class;
1115     BackendSetPtr found_set; // null
1116     BackendInstancePtr found_backend;
1117
1118     get_set(package, apdu_req, databases, query, found_backend, found_set);
1119     if (!found_set)
1120         return;
1121
1122     Z_NamePlusRecordList *npr_res = 0;
1123     // record_cache.lookup types are int's. Avoid non-fitting values
1124     if (*req->resultSetStartPoint > 0
1125         && *req->resultSetStartPoint < INT_MAX
1126         && *req->numberOfRecordsRequested > 0
1127         && *req->numberOfRecordsRequested < INT_MAX
1128         && found_set->m_record_cache.lookup(odr, &npr_res,
1129                                             *req->resultSetStartPoint,
1130                                             *req->numberOfRecordsRequested,
1131                                             req->preferredRecordSyntax,
1132                                             req->recordComposition))
1133     {
1134         Z_APDU *f_apdu_res = odr.create_presentResponse(apdu_req, 0, 0);
1135         Z_PresentResponse *f_resp = f_apdu_res->u.presentResponse;
1136
1137         yaz_log(YLOG_LOG, "Found " ODR_INT_PRINTF "+" ODR_INT_PRINTF
1138                 " records in cache %p",
1139                 *req->resultSetStartPoint,
1140                 *req->numberOfRecordsRequested,
1141                 &found_set->m_record_cache);
1142
1143         *f_resp->numberOfRecordsReturned = *req->numberOfRecordsRequested;
1144         *f_resp->nextResultSetPosition =
1145             *req->resultSetStartPoint + *req->numberOfRecordsRequested;
1146         // f_resp->presentStatus assumed OK.
1147         f_resp->records = (Z_Records *) odr_malloc(odr, sizeof(Z_Records));
1148         f_resp->records->which = Z_Records_DBOSD;
1149         f_resp->records->u.databaseOrSurDiagnostics = npr_res;
1150         package.response() = f_apdu_res;
1151         bc->release_backend(found_backend);
1152         return;
1153     }
1154
1155     found_backend->timestamp();
1156
1157     Z_APDU *p_apdu = zget_APDU(odr, Z_APDU_presentRequest);
1158     Z_PresentRequest *p_req = p_apdu->u.presentRequest;
1159     p_req->preferredRecordSyntax = req->preferredRecordSyntax;
1160     p_req->resultSetId = odr_strdup(odr, found_set->m_result_set_id.c_str());
1161     *p_req->resultSetStartPoint = *req->resultSetStartPoint;
1162     *p_req->numberOfRecordsRequested = *req->numberOfRecordsRequested;
1163     p_req->preferredRecordSyntax = req->preferredRecordSyntax;
1164     p_req->recordComposition = req->recordComposition;
1165
1166     Package present_package(found_backend->m_session, package.origin());
1167     present_package.copy_filter(package);
1168
1169     present_package.request() = p_apdu;
1170
1171     present_package.move();
1172
1173     Z_GDU *gdu = present_package.response().get();
1174     if (!present_package.session().is_closed()
1175         && gdu && gdu->which == Z_GDU_Z3950
1176         && gdu->u.z3950->which == Z_APDU_presentResponse)
1177     {
1178         Z_PresentResponse *b_resp = gdu->u.z3950->u.presentResponse;
1179         Z_APDU *f_apdu_res = odr.create_presentResponse(apdu_req, 0, 0);
1180         Z_PresentResponse *f_resp = f_apdu_res->u.presentResponse;
1181
1182         f_resp->numberOfRecordsReturned = b_resp->numberOfRecordsReturned;
1183         f_resp->nextResultSetPosition = b_resp->nextResultSetPosition;
1184         f_resp->presentStatus= b_resp->presentStatus;
1185         f_resp->records = b_resp->records;
1186         f_resp->otherInfo = b_resp->otherInfo;
1187         package.response() = f_apdu_res;
1188
1189         if (b_resp->records && b_resp->records->which ==  Z_Records_DBOSD)
1190         {
1191             Z_NamePlusRecordList *npr =
1192                 b_resp->records->u.databaseOrSurDiagnostics;
1193             // record_cache.add types are int's. Avoid non-fitting values
1194             if (*req->resultSetStartPoint > 0
1195                 && npr->num_records + *req->resultSetStartPoint < INT_MAX)
1196             {
1197 #if 0
1198                 yaz_log(YLOG_LOG, "Adding " ODR_INT_PRINTF "+" ODR_INT_PRINTF
1199                         " records to cache %p",
1200                         *req->resultSetStartPoint,
1201                         *f_resp->numberOfRecordsReturned,
1202                         &found_set->m_record_cache);
1203 #endif
1204                 found_set->m_record_cache.add(
1205                     odr, npr, *req->resultSetStartPoint,
1206                     p_req->recordComposition);
1207             }
1208         }
1209         bc->release_backend(found_backend);
1210     }
1211     else
1212     {
1213         bc->remove_backend(found_backend);
1214         Z_APDU *f_apdu_res =
1215             odr.create_presentResponse(
1216                 apdu_req, YAZ_BIB1_TEMPORARY_SYSTEM_ERROR,
1217                 "session_shared: target closed connection during present");
1218         package.response() = f_apdu_res;
1219     }
1220 }
1221
1222 void yf::SessionShared::Frontend::scan(mp::Package &frontend_package,
1223                                        Z_APDU *apdu_req)
1224 {
1225     BackendClassPtr bc = m_backend_class;
1226     BackendInstancePtr backend = bc->get_backend(frontend_package);
1227     if (!backend)
1228     {
1229         mp::odr odr;
1230         Z_APDU *apdu = odr.create_scanResponse(
1231             apdu_req, YAZ_BIB1_TEMPORARY_SYSTEM_ERROR,
1232             "session_shared: could not create backend");
1233         frontend_package.response() = apdu;
1234     }
1235     else
1236     {
1237         Package scan_package(backend->m_session, frontend_package.origin());
1238         backend->timestamp();
1239         scan_package.copy_filter(frontend_package);
1240         scan_package.request() = apdu_req;
1241         scan_package.move();
1242         frontend_package.response() = scan_package.response();
1243         if (scan_package.session().is_closed())
1244         {
1245             frontend_package.session().close();
1246             bc->remove_backend(backend);
1247         }
1248         else
1249             bc->release_backend(backend);
1250     }
1251 }
1252
1253 yf::SessionShared::Worker::Worker(SessionShared::Rep *rep) : m_p(rep)
1254 {
1255 }
1256
1257 void yf::SessionShared::Worker::operator() (void)
1258 {
1259     m_p->expire();
1260 }
1261
1262 bool yf::SessionShared::BackendClass::expire_instances()
1263 {
1264     time_t now;
1265     time(&now);
1266     boost::mutex::scoped_lock lock(m_mutex_backend_class);
1267     BackendInstanceList::iterator bit = m_backend_list.begin();
1268     while (bit != m_backend_list.end())
1269     {
1270         time_t last_use = (*bit)->m_time_last_use;
1271
1272         if ((*bit)->m_in_use)
1273         {
1274             bit++;
1275         }
1276         else if (now < last_use || now - last_use > m_backend_expiry_ttl)
1277         {
1278             bit = m_backend_list.erase(bit);
1279         }
1280         else
1281         {
1282             bit++;
1283         }
1284     }
1285     if (m_backend_list.empty())
1286         return true;
1287     return false;
1288 }
1289
1290 void yf::SessionShared::Rep::expire_classes()
1291 {
1292     boost::mutex::scoped_lock lock(m_mutex_backend_map);
1293     BackendClassMap::iterator b_it = m_backend_map.begin();
1294     while (b_it != m_backend_map.end())
1295     {
1296         if (b_it->second->expire_instances())
1297         {
1298             m_backend_map.erase(b_it);
1299             b_it = m_backend_map.begin();
1300         }
1301         else
1302             b_it++;
1303     }
1304 }
1305
1306 void yf::SessionShared::Rep::expire()
1307 {
1308     while (true)
1309     {
1310         boost::xtime xt;
1311         boost::xtime_get(&xt,
1312 #if BOOST_VERSION >= 105000
1313                 boost::TIME_UTC_
1314 #else
1315                 boost::TIME_UTC
1316 #endif
1317                   );
1318         xt.sec += m_session_ttl;
1319         {
1320             boost::mutex::scoped_lock lock(m_mutex);
1321             m_cond_expire_ready.timed_wait(lock, xt);
1322             if (close_down)
1323                 break;
1324         }
1325         stat();
1326         expire_classes();
1327     }
1328 }
1329
1330 yf::SessionShared::Rep::Rep()
1331 {
1332     m_resultset_ttl = 30;
1333     m_resultset_max = 10;
1334     m_session_ttl = 90;
1335     m_optimize_search = true;
1336     m_restart = false;
1337     m_session_max = 100;
1338     m_preferredMessageSize = 0;
1339     m_maximumRecordSize = 0;
1340     close_down = false;
1341 }
1342
1343 yf::SessionShared::Rep::~Rep()
1344 {
1345     {
1346         boost::mutex::scoped_lock lock(m_mutex);
1347         close_down = true;
1348         m_cond_expire_ready.notify_all();
1349     }
1350     m_thrds.join_all();
1351 }
1352
1353 void yf::SessionShared::Rep::start()
1354 {
1355     yf::SessionShared::Worker w(this);
1356     m_thrds.add_thread(new boost::thread(w));
1357 }
1358
1359 yf::SessionShared::SessionShared() : m_p(new SessionShared::Rep)
1360 {
1361 }
1362
1363 yf::SessionShared::~SessionShared() {
1364 }
1365
1366 void yf::SessionShared::start() const
1367 {
1368     m_p->start();
1369 }
1370
1371 yf::SessionShared::Frontend::Frontend(Rep *rep) : m_is_virtual(false), m_p(rep)
1372 {
1373 }
1374
1375 yf::SessionShared::Frontend::~Frontend()
1376 {
1377 }
1378
1379 yf::SessionShared::FrontendPtr yf::SessionShared::Rep::get_frontend(mp::Package &package)
1380 {
1381     boost::mutex::scoped_lock lock(m_mutex);
1382
1383     std::map<mp::Session,yf::SessionShared::FrontendPtr>::iterator it;
1384
1385     while(true)
1386     {
1387         it = m_clients.find(package.session());
1388         if (it == m_clients.end())
1389             break;
1390
1391         if (!it->second->m_in_use)
1392         {
1393             it->second->m_in_use = true;
1394             return it->second;
1395         }
1396         m_cond_session_ready.wait(lock);
1397     }
1398     FrontendPtr f(new Frontend(this));
1399     m_clients[package.session()] = f;
1400     f->m_in_use = true;
1401     return f;
1402 }
1403
1404 void yf::SessionShared::Rep::release_frontend(mp::Package &package)
1405 {
1406     boost::mutex::scoped_lock lock(m_mutex);
1407     std::map<mp::Session,yf::SessionShared::FrontendPtr>::iterator it;
1408
1409     it = m_clients.find(package.session());
1410     if (it != m_clients.end())
1411     {
1412         if (package.session().is_closed())
1413         {
1414             m_clients.erase(it);
1415         }
1416         else
1417         {
1418             it->second->m_in_use = false;
1419         }
1420         m_cond_session_ready.notify_all();
1421     }
1422 }
1423
1424
1425 void yf::SessionShared::process(mp::Package &package) const
1426 {
1427     FrontendPtr f = m_p->get_frontend(package);
1428
1429     Z_GDU *gdu = package.request().get();
1430
1431     if (gdu && gdu->which == Z_GDU_Z3950 && gdu->u.z3950->which ==
1432         Z_APDU_initRequest && !f->m_is_virtual)
1433     {
1434         m_p->init(package, gdu, f);
1435     }
1436     else if (!f->m_is_virtual)
1437         package.move();
1438     else if (gdu && gdu->which == Z_GDU_Z3950)
1439     {
1440         Z_APDU *apdu = gdu->u.z3950;
1441         if (apdu->which == Z_APDU_initRequest)
1442         {
1443             mp::odr odr;
1444
1445             package.response() = odr.create_close(
1446                 apdu,
1447                 Z_Close_protocolError,
1448                 "double init");
1449
1450             package.session().close();
1451         }
1452         else if (apdu->which == Z_APDU_close)
1453         {
1454             mp::odr odr;
1455
1456             package.response() = odr.create_close(
1457                 apdu,
1458                 Z_Close_peerAbort, "received close from client");
1459             package.session().close();
1460         }
1461         else if (apdu->which == Z_APDU_searchRequest)
1462         {
1463             f->search(package, apdu);
1464         }
1465         else if (apdu->which == Z_APDU_presentRequest)
1466         {
1467             f->present(package, apdu);
1468         }
1469         else if (apdu->which == Z_APDU_scanRequest)
1470         {
1471             f->scan(package, apdu);
1472         }
1473         else
1474         {
1475             mp::odr odr;
1476
1477             package.response() = odr.create_close(
1478                 apdu, Z_Close_protocolError,
1479                 "unsupported APDU in filter_session_shared");
1480
1481             package.session().close();
1482         }
1483     }
1484     m_p->release_frontend(package);
1485 }
1486
1487 void yf::SessionShared::configure(const xmlNode *ptr, bool test_only,
1488                                   const char *path)
1489 {
1490     for (ptr = ptr->children; ptr; ptr = ptr->next)
1491     {
1492         if (ptr->type != XML_ELEMENT_NODE)
1493             continue;
1494         if (!strcmp((const char *) ptr->name, "resultset"))
1495         {
1496             const struct _xmlAttr *attr;
1497             for (attr = ptr->properties; attr; attr = attr->next)
1498             {
1499                 if (!strcmp((const char *) attr->name, "ttl"))
1500                     m_p->m_resultset_ttl =
1501                         mp::xml::get_int(attr->children, 30);
1502                 else if (!strcmp((const char *) attr->name, "max"))
1503                 {
1504                     m_p->m_resultset_max =
1505                         mp::xml::get_int(attr->children, 10);
1506                 }
1507                 else if (!strcmp((const char *) attr->name, "optimizesearch"))
1508                 {
1509                     m_p->m_optimize_search =
1510                         mp::xml::get_bool(attr->children, true);
1511                 }
1512                 else if (!strcmp((const char *) attr->name, "restart"))
1513                 {
1514                     m_p->m_restart = mp::xml::get_bool(attr->children, true);
1515                 }
1516                 else
1517                     throw mp::filter::FilterException(
1518                         "Bad attribute " + std::string((const char *)
1519                                                        attr->name));
1520             }
1521         }
1522         else if (!strcmp((const char *) ptr->name, "session"))
1523         {
1524             const struct _xmlAttr *attr;
1525             for (attr = ptr->properties; attr; attr = attr->next)
1526             {
1527                 if (!strcmp((const char *) attr->name, "ttl"))
1528                     m_p->m_session_ttl =
1529                         mp::xml::get_int(attr->children, 90);
1530                 else if (!strcmp((const char *) attr->name, "max"))
1531                     m_p->m_session_max =
1532                         mp::xml::get_int(attr->children, 100);
1533                 else
1534                     throw mp::filter::FilterException(
1535                         "Bad attribute " + std::string((const char *)
1536                                                        attr->name));
1537             }
1538         }
1539         else if (!strcmp((const char *) ptr->name, "init"))
1540         {
1541             const struct _xmlAttr *attr;
1542             for (attr = ptr->properties; attr; attr = attr->next)
1543             {
1544                 if (!strcmp((const char *) attr->name, "maximum-record-size"))
1545                     m_p->m_maximumRecordSize =
1546                         mp::xml::get_int(attr->children, 0);
1547                 else if (!strcmp((const char *) attr->name,
1548                                  "preferred-message-size"))
1549                     m_p->m_preferredMessageSize =
1550                         mp::xml::get_int(attr->children, 0);
1551                 else
1552                     throw mp::filter::FilterException(
1553                         "Bad attribute " + std::string((const char *)
1554                                                        attr->name));
1555             }
1556         }
1557         else
1558         {
1559             throw mp::filter::FilterException("Bad element "
1560                                                + std::string((const char *)
1561                                                              ptr->name));
1562         }
1563     }
1564 }
1565
1566 static mp::filter::Base* filter_creator()
1567 {
1568     return new mp::filter::SessionShared;
1569 }
1570
1571 extern "C" {
1572     struct metaproxy_1_filter_struct metaproxy_1_filter_session_shared = {
1573         0,
1574         "session_shared",
1575         filter_creator
1576     };
1577 }
1578
1579 /*
1580  * Local variables:
1581  * c-basic-offset: 4
1582  * c-file-style: "Stroustrup"
1583  * indent-tabs-mode: nil
1584  * End:
1585  * vim: shiftwidth=4 tabstop=8 expandtab
1586  */
1587