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             found_set.reset();
 950             return; // search error
 951         }
 952     }
 953     if (m_p->m_restart && !session_restarted && new_set->m_result_set_size < 0)
 954     {
 955         package.log("session_shared", YLOG_LOG, "restart");
 956         bc->remove_backend(found_backend);
 957         session_restarted = true;
 958         found_backend.reset();
 959         goto restart;
 960     }
 961
 962 #if 0
 963     found_set = new_set;
 964     found_set->timestamp();
 965     found_backend->m_sets.push_back(found_set);
 966 #endif
 967 }
 968
 969 int yf::SessionShared::Frontend::result_set_ref(ODR o,
 970                                                 const Databases &databases,
 971                                                 Z_RPNStructure *s,
 972                                                 std::string &rset)
 973 {
 974     int ret = 0;
 975     switch (s->which)
 976     {
 977     case Z_RPNStructure_simple:
 978         if (s->u.simple->which == Z_Operand_resultSetId)
 979         {
 980             const char *id = s->u.simple->u.resultSetId;
 981             rset = id;
 982
 983             FrontendSets::iterator fset_it = m_frontend_sets.find(id);
 984             if (fset_it == m_frontend_sets.end())
 985             {
 986                 ret = YAZ_BIB1_SPECIFIED_RESULT_SET_DOES_NOT_EXIST;
 987             }
 988             else if (fset_it->second->get_databases() != databases)
 989             {
 990                 ret = YAZ_BIB1_SPECIFIED_RESULT_SET_DOES_NOT_EXIST;
 991             }
 992             else
 993             {
 994                 yazpp_1::Yaz_Z_Query query = fset_it->second->get_query();
 995                 Z_Query *q = yaz_copy_Z_Query(query.get_Z_Query(), o);
 996                 if (q->which == Z_Query_type_1 || q->which == Z_Query_type_101)
 997                 {
 998                     s->which = q->u.type_1->RPNStructure->which;
 999                     s->u.simple = q->u.type_1->RPNStructure->u.simple;
1000                 }
1001                 else
1002                 {
1003                     ret = YAZ_BIB1_SPECIFIED_RESULT_SET_DOES_NOT_EXIST;
1004                 }
1005             }
1006         }
1007         break;
1008     case Z_RPNStructure_complex:
1009         ret = result_set_ref(o, databases, s->u.complex->s1, rset);
1010         if (!ret)
1011             ret = result_set_ref(o, databases, s->u.complex->s2, rset);
1012         break;
1013     }
1014     return ret;
1015 }
1016
1017 void yf::SessionShared::Frontend::search(mp::Package &package,
1018                                          Z_APDU *apdu_req)
1019 {
1020     Z_SearchRequest *req = apdu_req->u.searchRequest;
1021     FrontendSets::iterator fset_it =
1022         m_frontend_sets.find(req->resultSetName);
1023     if (fset_it != m_frontend_sets.end())
1024     {
1025         // result set already exist
1026         // if replace indicator is off: we return diagnostic if
1027         // result set already exist.
1028         if (*req->replaceIndicator == 0)
1029         {
1030             mp::odr odr;
1031             Z_APDU *apdu =
1032                 odr.create_searchResponse(
1033                     apdu_req,
1034                     YAZ_BIB1_RESULT_SET_EXISTS_AND_REPLACE_INDICATOR_OFF,
1035                     0);
1036             package.response() = apdu;
1037             return;
1038         }
1039         m_frontend_sets.erase(fset_it);
1040     }
1041
1042     Databases databases;
1043     int i;
1044     for (i = 0; i < req->num_databaseNames; i++)
1045         databases.push_back(req->databaseNames[i]);
1046
1047
1048     yazpp_1::Yaz_Z_Query query;
1049     query.set_Z_Query(req->query);
1050
1051     Z_Query *q = query.get_Z_Query();
1052     if (q->which == Z_Query_type_1 || q->which == Z_Query_type_101)
1053     {
1054         mp::odr odr;
1055         std::string rset;
1056         int diag = result_set_ref(odr, databases, q->u.type_1->RPNStructure,
1057                                   rset);
1058         if (diag)
1059         {
1060             Z_APDU *apdu =
1061                 odr.create_searchResponse(
1062                     apdu_req,
1063                     diag,
1064                     rset.c_str());
1065             package.response() = apdu;
1066             return;
1067         }
1068         query.set_Z_Query(q);
1069     }
1070
1071     BackendSetPtr found_set; // null
1072     BackendInstancePtr found_backend; // null
1073
1074     get_set(package, apdu_req, databases, query, found_backend, found_set);
1075     if (!found_set)
1076         return;
1077
1078     mp::odr odr;
1079     Z_APDU *f_apdu = odr.create_searchResponse(apdu_req, 0, 0);
1080     Z_SearchResponse *f_resp = f_apdu->u.searchResponse;
1081     *f_resp->resultCount = found_set->m_result_set_size;
1082     f_resp->additionalSearchInfo = found_set->additionalSearchInfoResponse;
1083     package.response() = f_apdu;
1084
1085     FrontendSetPtr fset(new FrontendSet(databases, query));
1086     m_frontend_sets[req->resultSetName] = fset;
1087
1088     m_backend_class->release_backend(found_backend);
1089 }
1090
1091 void yf::SessionShared::Frontend::present(mp::Package &package,
1092                                           Z_APDU *apdu_req)
1093 {
1094     mp::odr odr;
1095     Z_PresentRequest *req = apdu_req->u.presentRequest;
1096
1097     FrontendSets::iterator fset_it =
1098         m_frontend_sets.find(req->resultSetId);
1099
1100     if (fset_it == m_frontend_sets.end())
1101     {
1102         Z_APDU *apdu =
1103             odr.create_presentResponse(
1104                 apdu_req,
1105                 YAZ_BIB1_SPECIFIED_RESULT_SET_DOES_NOT_EXIST,
1106                 req->resultSetId);
1107         package.response() = apdu;
1108         return;
1109     }
1110     FrontendSetPtr fset = fset_it->second;
1111
1112     Databases databases = fset->get_databases();
1113     yazpp_1::Yaz_Z_Query query = fset->get_query();
1114
1115     BackendClassPtr bc = m_backend_class;
1116     BackendSetPtr found_set; // null
1117     BackendInstancePtr found_backend;
1118
1119     get_set(package, apdu_req, databases, query, found_backend, found_set);
1120     if (!found_set)
1121         return;
1122
1123     Z_NamePlusRecordList *npr_res = 0;
1124     // record_cache.lookup types are int's. Avoid non-fitting values
1125     if (*req->resultSetStartPoint > 0
1126         && *req->resultSetStartPoint < INT_MAX
1127         && *req->numberOfRecordsRequested > 0
1128         && *req->numberOfRecordsRequested < INT_MAX
1129         && found_set->m_record_cache.lookup(odr, &npr_res,
1130                                             *req->resultSetStartPoint,
1131                                             *req->numberOfRecordsRequested,
1132                                             req->preferredRecordSyntax,
1133                                             req->recordComposition))
1134     {
1135         Z_APDU *f_apdu_res = odr.create_presentResponse(apdu_req, 0, 0);
1136         Z_PresentResponse *f_resp = f_apdu_res->u.presentResponse;
1137
1138         yaz_log(YLOG_LOG, "Found " ODR_INT_PRINTF "+" ODR_INT_PRINTF
1139                 " records in cache %p",
1140                 *req->resultSetStartPoint,
1141                 *req->numberOfRecordsRequested,
1142                 &found_set->m_record_cache);
1143
1144         *f_resp->numberOfRecordsReturned = *req->numberOfRecordsRequested;
1145         *f_resp->nextResultSetPosition =
1146             *req->resultSetStartPoint + *req->numberOfRecordsRequested;
1147         // f_resp->presentStatus assumed OK.
1148         f_resp->records = (Z_Records *) odr_malloc(odr, sizeof(Z_Records));
1149         f_resp->records->which = Z_Records_DBOSD;
1150         f_resp->records->u.databaseOrSurDiagnostics = npr_res;
1151         package.response() = f_apdu_res;
1152         bc->release_backend(found_backend);
1153         return;
1154     }
1155
1156     found_backend->timestamp();
1157
1158     Z_APDU *p_apdu = zget_APDU(odr, Z_APDU_presentRequest);
1159     Z_PresentRequest *p_req = p_apdu->u.presentRequest;
1160     p_req->preferredRecordSyntax = req->preferredRecordSyntax;
1161     p_req->resultSetId = odr_strdup(odr, found_set->m_result_set_id.c_str());
1162     *p_req->resultSetStartPoint = *req->resultSetStartPoint;
1163     *p_req->numberOfRecordsRequested = *req->numberOfRecordsRequested;
1164     p_req->preferredRecordSyntax = req->preferredRecordSyntax;
1165     p_req->recordComposition = req->recordComposition;
1166
1167     Package present_package(found_backend->m_session, package.origin());
1168     present_package.copy_filter(package);
1169
1170     present_package.request() = p_apdu;
1171
1172     present_package.move();
1173
1174     Z_GDU *gdu = present_package.response().get();
1175     if (!present_package.session().is_closed()
1176         && gdu && gdu->which == Z_GDU_Z3950
1177         && gdu->u.z3950->which == Z_APDU_presentResponse)
1178     {
1179         Z_PresentResponse *b_resp = gdu->u.z3950->u.presentResponse;
1180         Z_APDU *f_apdu_res = odr.create_presentResponse(apdu_req, 0, 0);
1181         Z_PresentResponse *f_resp = f_apdu_res->u.presentResponse;
1182
1183         f_resp->numberOfRecordsReturned = b_resp->numberOfRecordsReturned;
1184         f_resp->nextResultSetPosition = b_resp->nextResultSetPosition;
1185         f_resp->presentStatus= b_resp->presentStatus;
1186         f_resp->records = b_resp->records;
1187         f_resp->otherInfo = b_resp->otherInfo;
1188         package.response() = f_apdu_res;
1189
1190         if (b_resp->records && b_resp->records->which ==  Z_Records_DBOSD)
1191         {
1192             Z_NamePlusRecordList *npr =
1193                 b_resp->records->u.databaseOrSurDiagnostics;
1194             // record_cache.add types are int's. Avoid non-fitting values
1195             if (*req->resultSetStartPoint > 0
1196                 && npr->num_records + *req->resultSetStartPoint < INT_MAX)
1197             {
1198 #if 0
1199                 yaz_log(YLOG_LOG, "Adding " ODR_INT_PRINTF "+" ODR_INT_PRINTF
1200                         " records to cache %p",
1201                         *req->resultSetStartPoint,
1202                         *f_resp->numberOfRecordsReturned,
1203                         &found_set->m_record_cache);
1204 #endif
1205                 found_set->m_record_cache.add(
1206                     odr, npr, *req->resultSetStartPoint,
1207                     p_req->recordComposition);
1208             }
1209         }
1210         bc->release_backend(found_backend);
1211     }
1212     else
1213     {
1214         bc->remove_backend(found_backend);
1215         Z_APDU *f_apdu_res =
1216             odr.create_presentResponse(
1217                 apdu_req, YAZ_BIB1_TEMPORARY_SYSTEM_ERROR,
1218                 "session_shared: target closed connection during present");
1219         package.response() = f_apdu_res;
1220     }
1221 }
1222
1223 void yf::SessionShared::Frontend::scan(mp::Package &frontend_package,
1224                                        Z_APDU *apdu_req)
1225 {
1226     BackendClassPtr bc = m_backend_class;
1227     BackendInstancePtr backend = bc->get_backend(frontend_package);
1228     if (!backend)
1229     {
1230         mp::odr odr;
1231         Z_APDU *apdu = odr.create_scanResponse(
1232             apdu_req, YAZ_BIB1_TEMPORARY_SYSTEM_ERROR,
1233             "session_shared: could not create backend");
1234         frontend_package.response() = apdu;
1235     }
1236     else
1237     {
1238         Package scan_package(backend->m_session, frontend_package.origin());
1239         backend->timestamp();
1240         scan_package.copy_filter(frontend_package);
1241         scan_package.request() = apdu_req;
1242         scan_package.move();
1243         frontend_package.response() = scan_package.response();
1244         if (scan_package.session().is_closed())
1245         {
1246             frontend_package.session().close();
1247             bc->remove_backend(backend);
1248         }
1249         else
1250             bc->release_backend(backend);
1251     }
1252 }
1253
1254 yf::SessionShared::Worker::Worker(SessionShared::Rep *rep) : m_p(rep)
1255 {
1256 }
1257
1258 void yf::SessionShared::Worker::operator() (void)
1259 {
1260     m_p->expire();
1261 }
1262
1263 bool yf::SessionShared::BackendClass::expire_instances()
1264 {
1265     time_t now;
1266     time(&now);
1267     boost::mutex::scoped_lock lock(m_mutex_backend_class);
1268     BackendInstanceList::iterator bit = m_backend_list.begin();
1269     while (bit != m_backend_list.end())
1270     {
1271         time_t last_use = (*bit)->m_time_last_use;
1272
1273         if ((*bit)->m_in_use)
1274         {
1275             bit++;
1276         }
1277         else if (now < last_use || now - last_use > m_backend_expiry_ttl)
1278         {
1279             bit = m_backend_list.erase(bit);
1280         }
1281         else
1282         {
1283             bit++;
1284         }
1285     }
1286     if (m_backend_list.empty())
1287         return true;
1288     return false;
1289 }
1290
1291 void yf::SessionShared::Rep::expire_classes()
1292 {
1293     boost::mutex::scoped_lock lock(m_mutex_backend_map);
1294     BackendClassMap::iterator b_it = m_backend_map.begin();
1295     while (b_it != m_backend_map.end())
1296     {
1297         if (b_it->second->expire_instances())
1298         {
1299             m_backend_map.erase(b_it);
1300             b_it = m_backend_map.begin();
1301         }
1302         else
1303             b_it++;
1304     }
1305 }
1306
1307 void yf::SessionShared::Rep::expire()
1308 {
1309     while (true)
1310     {
1311         boost::xtime xt;
1312         boost::xtime_get(&xt,
1313 #if BOOST_VERSION >= 105000
1314                 boost::TIME_UTC_
1315 #else
1316                 boost::TIME_UTC
1317 #endif
1318                   );
1319         xt.sec += m_session_ttl;
1320         {
1321             boost::mutex::scoped_lock lock(m_mutex);
1322             m_cond_expire_ready.timed_wait(lock, xt);
1323             if (close_down)
1324                 break;
1325         }
1326         stat();
1327         expire_classes();
1328     }
1329 }
1330
1331 yf::SessionShared::Rep::Rep()
1332 {
1333     m_resultset_ttl = 30;
1334     m_resultset_max = 10;
1335     m_session_ttl = 90;
1336     m_optimize_search = true;
1337     m_restart = false;
1338     m_session_max = 100;
1339     m_preferredMessageSize = 0;
1340     m_maximumRecordSize = 0;
1341     close_down = false;
1342 }
1343
1344 yf::SessionShared::Rep::~Rep()
1345 {
1346     {
1347         boost::mutex::scoped_lock lock(m_mutex);
1348         close_down = true;
1349         m_cond_expire_ready.notify_all();
1350     }
1351     m_thrds.join_all();
1352 }
1353
1354 void yf::SessionShared::Rep::start()
1355 {
1356     yf::SessionShared::Worker w(this);
1357     m_thrds.add_thread(new boost::thread(w));
1358 }
1359
1360 yf::SessionShared::SessionShared() : m_p(new SessionShared::Rep)
1361 {
1362 }
1363
1364 yf::SessionShared::~SessionShared() {
1365 }
1366
1367 void yf::SessionShared::start() const
1368 {
1369     m_p->start();
1370 }
1371
1372 yf::SessionShared::Frontend::Frontend(Rep *rep) : m_is_virtual(false), m_p(rep)
1373 {
1374 }
1375
1376 yf::SessionShared::Frontend::~Frontend()
1377 {
1378 }
1379
1380 yf::SessionShared::FrontendPtr yf::SessionShared::Rep::get_frontend(mp::Package &package)
1381 {
1382     boost::mutex::scoped_lock lock(m_mutex);
1383
1384     std::map<mp::Session,yf::SessionShared::FrontendPtr>::iterator it;
1385
1386     while(true)
1387     {
1388         it = m_clients.find(package.session());
1389         if (it == m_clients.end())
1390             break;
1391
1392         if (!it->second->m_in_use)
1393         {
1394             it->second->m_in_use = true;
1395             return it->second;
1396         }
1397         m_cond_session_ready.wait(lock);
1398     }
1399     FrontendPtr f(new Frontend(this));
1400     m_clients[package.session()] = f;
1401     f->m_in_use = true;
1402     return f;
1403 }
1404
1405 void yf::SessionShared::Rep::release_frontend(mp::Package &package)
1406 {
1407     boost::mutex::scoped_lock lock(m_mutex);
1408     std::map<mp::Session,yf::SessionShared::FrontendPtr>::iterator it;
1409
1410     it = m_clients.find(package.session());
1411     if (it != m_clients.end())
1412     {
1413         if (package.session().is_closed())
1414         {
1415             m_clients.erase(it);
1416         }
1417         else
1418         {
1419             it->second->m_in_use = false;
1420         }
1421         m_cond_session_ready.notify_all();
1422     }
1423 }
1424
1425
1426 void yf::SessionShared::process(mp::Package &package) const
1427 {
1428     FrontendPtr f = m_p->get_frontend(package);
1429
1430     Z_GDU *gdu = package.request().get();
1431
1432     if (gdu && gdu->which == Z_GDU_Z3950 && gdu->u.z3950->which ==
1433         Z_APDU_initRequest && !f->m_is_virtual)
1434     {
1435         m_p->init(package, gdu, f);
1436     }
1437     else if (!f->m_is_virtual)
1438         package.move();
1439     else if (gdu && gdu->which == Z_GDU_Z3950)
1440     {
1441         Z_APDU *apdu = gdu->u.z3950;
1442         if (apdu->which == Z_APDU_initRequest)
1443         {
1444             mp::odr odr;
1445
1446             package.response() = odr.create_close(
1447                 apdu,
1448                 Z_Close_protocolError,
1449                 "double init");
1450
1451             package.session().close();
1452         }
1453         else if (apdu->which == Z_APDU_close)
1454         {
1455             mp::odr odr;
1456
1457             package.response() = odr.create_close(
1458                 apdu,
1459                 Z_Close_peerAbort, "received close from client");
1460             package.session().close();
1461         }
1462         else if (apdu->which == Z_APDU_searchRequest)
1463         {
1464             f->search(package, apdu);
1465         }
1466         else if (apdu->which == Z_APDU_presentRequest)
1467         {
1468             f->present(package, apdu);
1469         }
1470         else if (apdu->which == Z_APDU_scanRequest)
1471         {
1472             f->scan(package, apdu);
1473         }
1474         else
1475         {
1476             mp::odr odr;
1477
1478             package.response() = odr.create_close(
1479                 apdu, Z_Close_protocolError,
1480                 "unsupported APDU in filter_session_shared");
1481
1482             package.session().close();
1483         }
1484     }
1485     m_p->release_frontend(package);
1486 }
1487
1488 void yf::SessionShared::configure(const xmlNode *ptr, bool test_only,
1489                                   const char *path)
1490 {
1491     for (ptr = ptr->children; ptr; ptr = ptr->next)
1492     {
1493         if (ptr->type != XML_ELEMENT_NODE)
1494             continue;
1495         if (!strcmp((const char *) ptr->name, "resultset"))
1496         {
1497             const struct _xmlAttr *attr;
1498             for (attr = ptr->properties; attr; attr = attr->next)
1499             {
1500                 if (!strcmp((const char *) attr->name, "ttl"))
1501                     m_p->m_resultset_ttl =
1502                         mp::xml::get_int(attr->children, 30);
1503                 else if (!strcmp((const char *) attr->name, "max"))
1504                 {
1505                     m_p->m_resultset_max =
1506                         mp::xml::get_int(attr->children, 10);
1507                 }
1508                 else if (!strcmp((const char *) attr->name, "optimizesearch"))
1509                 {
1510                     m_p->m_optimize_search =
1511                         mp::xml::get_bool(attr->children, true);
1512                 }
1513                 else if (!strcmp((const char *) attr->name, "restart"))
1514                 {
1515                     m_p->m_restart = mp::xml::get_bool(attr->children, true);
1516                 }
1517                 else
1518                     throw mp::filter::FilterException(
1519                         "Bad attribute " + std::string((const char *)
1520                                                        attr->name));
1521             }
1522         }
1523         else if (!strcmp((const char *) ptr->name, "session"))
1524         {
1525             const struct _xmlAttr *attr;
1526             for (attr = ptr->properties; attr; attr = attr->next)
1527             {
1528                 if (!strcmp((const char *) attr->name, "ttl"))
1529                     m_p->m_session_ttl =
1530                         mp::xml::get_int(attr->children, 90);
1531                 else if (!strcmp((const char *) attr->name, "max"))
1532                     m_p->m_session_max =
1533                         mp::xml::get_int(attr->children, 100);
1534                 else
1535                     throw mp::filter::FilterException(
1536                         "Bad attribute " + std::string((const char *)
1537                                                        attr->name));
1538             }
1539         }
1540         else if (!strcmp((const char *) ptr->name, "init"))
1541         {
1542             const struct _xmlAttr *attr;
1543             for (attr = ptr->properties; attr; attr = attr->next)
1544             {
1545                 if (!strcmp((const char *) attr->name, "maximum-record-size"))
1546                     m_p->m_maximumRecordSize =
1547                         mp::xml::get_int(attr->children, 0);
1548                 else if (!strcmp((const char *) attr->name,
1549                                  "preferred-message-size"))
1550                     m_p->m_preferredMessageSize =
1551                         mp::xml::get_int(attr->children, 0);
1552                 else
1553                     throw mp::filter::FilterException(
1554                         "Bad attribute " + std::string((const char *)
1555                                                        attr->name));
1556             }
1557         }
1558         else
1559         {
1560             throw mp::filter::FilterException("Bad element "
1561                                                + std::string((const char *)
1562                                                              ptr->name));
1563         }
1564     }
1565 }
1566
1567 static mp::filter::Base* filter_creator()
1568 {
1569     return new mp::filter::SessionShared;
1570 }
1571
1572 extern "C" {
1573     struct metaproxy_1_filter_struct metaproxy_1_filter_session_shared = {
1574         0,
1575         "session_shared",
1576         filter_creator
1577     };
1578 }
1579
1580 /*
1581  * Local variables:
1582  * c-basic-offset: 4
1583  * c-file-style: "Stroustrup"
1584  * indent-tabs-mode: nil
1585  * End:
1586  * vim: shiftwidth=4 tabstop=8 expandtab
1587  */
1588