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     m_cond_set_ready.notify_all();
 483     return null;
 484 }
 485
 486
 487 yf::SessionShared::BackendClass::BackendClass(const yazpp_1::GDU &init_request,
 488                                               int resultset_ttl,
 489                                               int resultset_max,
 490                                               int session_ttl,
 491                                               Odr_int preferredMessageSize,
 492                                               Odr_int maximumRecordSize)
 493     : m_named_result_sets(false), m_init_request(init_request),
 494       m_sequence_top(0), m_backend_set_ttl(resultset_ttl),
 495       m_backend_expiry_ttl(session_ttl), m_backend_set_max(resultset_max),
 496       m_preferredMessageSize(preferredMessageSize),
 497       m_maximumRecordSize(maximumRecordSize),
 498       m_no_failed(0), m_no_succeeded(0), m_no_init(0)
 499 {}
 500
 501 yf::SessionShared::BackendClass::~BackendClass()
 502 {}
 503
 504 void yf::SessionShared::Rep::stat()
 505 {
 506     int no_classes = 0;
 507     int no_instances = 0;
 508     BackendClassMap::const_iterator it;
 509     {
 510         boost::mutex::scoped_lock lock(m_mutex_backend_map);
 511         for (it = m_backend_map.begin(); it != m_backend_map.end(); it++)
 512         {
 513             BackendClassPtr bc = it->second;
 514             no_classes++;
 515             BackendInstanceList::iterator bit = bc->m_backend_list.begin();
 516             for (; bit != bc->m_backend_list.end(); bit++)
 517                 no_instances++;
 518         }
 519     }
 520 }
 521
 522 void yf::SessionShared::Rep::init(mp::Package &package, const Z_GDU *gdu,
 523                                   FrontendPtr frontend)
 524 {
 525     Z_InitRequest *req = gdu->u.z3950->u.initRequest;
 526
 527     frontend->m_is_virtual = true;
 528     frontend->m_init_options = *req->options;
 529     InitKey k(req);
 530     {
 531         boost::mutex::scoped_lock lock(m_mutex_backend_map);
 532         BackendClassMap::const_iterator it;
 533         it = m_backend_map.find(k);
 534         if (it == m_backend_map.end())
 535         {
 536             BackendClassPtr b(new BackendClass(gdu->u.z3950,
 537                                                m_resultset_ttl,
 538                                                m_resultset_max,
 539                                                m_session_ttl,
 540                                                m_preferredMessageSize,
 541                                                m_maximumRecordSize));
 542             m_backend_map[k] = b;
 543             frontend->m_backend_class = b;
 544         }
 545         else
 546         {
 547             frontend->m_backend_class = it->second;
 548         }
 549     }
 550     BackendClassPtr bc = frontend->m_backend_class;
 551     mp::odr odr;
 552
 553     // we only need to get init response from "first" target in
 554     // backend class - the assumption being that init response is
 555     // same for all
 556     bool create_first_one = false;
 557     {
 558         boost::mutex::scoped_lock lock(bc->m_mutex_backend_class);
 559         if (!bc->m_no_failed && !bc->m_no_succeeded && !bc->m_no_init)
 560             create_first_one = true;
 561         else
 562         {
 563             // first for first one to finish
 564             while (!bc->m_no_failed && !bc->m_no_succeeded && bc->m_no_init)
 565             {
 566                 bc->m_cond_set_ready.wait(lock);
 567             }
 568         }
 569     }
 570     if (create_first_one)
 571     {
 572         BackendInstancePtr backend = bc->create_backend(package);
 573         if (backend)
 574             bc->release_backend(backend);
 575     }
 576     yazpp_1::GDU init_response;
 577     {
 578         boost::mutex::scoped_lock lock(bc->m_mutex_backend_class);
 579
 580         init_response = bc->m_init_response;
 581     }
 582
 583     if (init_response.get())
 584     {
 585         Z_GDU *response_gdu = init_response.get();
 586         mp::util::transfer_referenceId(odr, gdu->u.z3950,
 587                                        response_gdu->u.z3950);
 588         Z_InitResponse *init_res = response_gdu->u.z3950->u.initResponse;
 589         Z_Options *server_options = init_res->options;
 590         Z_Options *client_options = &frontend->m_init_options;
 591         int i;
 592         for (i = 0; i < 30; i++)
 593             if (!ODR_MASK_GET(client_options, i))
 594                 ODR_MASK_CLEAR(server_options, i);
 595
 596         if (!m_preferredMessageSize ||
 597             *init_res->preferredMessageSize > *req->preferredMessageSize)
 598             *init_res->preferredMessageSize = *req->preferredMessageSize;
 599
 600         if (!m_maximumRecordSize ||
 601             *init_res->maximumRecordSize > *req->maximumRecordSize)
 602             *init_res->maximumRecordSize = *req->maximumRecordSize;
 603
 604         package.response() = init_response;
 605         if (!*response_gdu->u.z3950->u.initResponse->result)
 606             package.session().close();
 607     }
 608     else
 609     {
 610         Z_APDU *apdu =
 611             odr.create_initResponse(
 612                 gdu->u.z3950, YAZ_BIB1_TEMPORARY_SYSTEM_ERROR,
 613                 "session_shared: target closed connection during init");
 614         *apdu->u.initResponse->result = 0;
 615         package.response() = apdu;
 616         package.session().close();
 617     }
 618 }
 619
 620 void yf::SessionShared::BackendSet::timestamp()
 621 {
 622     time(&m_time_last_use);
 623 }
 624
 625 yf::SessionShared::BackendSet::BackendSet(
 626     const std::string &result_set_id,
 627     const Databases &databases,
 628     const yazpp_1::Yaz_Z_Query &query,
 629     Z_OtherInformation *additionalSearchInfo) :
 630     m_result_set_id(result_set_id),
 631     m_databases(databases), m_result_set_size(0), m_query(query)
 632 {
 633     timestamp();
 634     mem_additionalSearchInfo = nmem_create();
 635     additionalSearchInfoResponse = 0;
 636     additionalSearchInfoRequest =
 637         yaz_clone_z_OtherInformation(additionalSearchInfo,
 638                                      mem_additionalSearchInfo);
 639 }
 640
 641 yf::SessionShared::BackendSet::~BackendSet()
 642 {
 643     nmem_destroy(mem_additionalSearchInfo);
 644 }
 645
 646 static int get_diagnostic(Z_DefaultDiagFormat *r)
 647 {
 648     return *r->condition;
 649 }
 650
 651 bool yf::SessionShared::BackendSet::search(
 652     mp::Package &frontend_package,
 653     mp::Package &search_package,
 654     const Z_APDU *frontend_apdu,
 655     const BackendInstancePtr bp,
 656     Z_Records **z_records)
 657 {
 658     mp::odr odr;
 659     Z_APDU *apdu_req = zget_APDU(odr, Z_APDU_searchRequest);
 660     Z_SearchRequest *req = apdu_req->u.searchRequest;
 661
 662     req->additionalSearchInfo = additionalSearchInfoRequest;
 663     req->resultSetName = odr_strdup(odr, m_result_set_id.c_str());
 664     req->query = m_query.get_Z_Query();
 665
 666     req->num_databaseNames = m_databases.size();
 667     req->databaseNames = (char**)
 668         odr_malloc(odr, req->num_databaseNames * sizeof(char *));
 669     Databases::const_iterator it = m_databases.begin();
 670     size_t i = 0;
 671     for (; it != m_databases.end(); it++)
 672         req->databaseNames[i++] = odr_strdup(odr, it->c_str());
 673
 674     if (frontend_apdu->which == Z_APDU_searchRequest)
 675         req->preferredRecordSyntax =
 676             frontend_apdu->u.searchRequest->preferredRecordSyntax;
 677
 678     search_package.request() = apdu_req;
 679
 680     search_package.move();
 681
 682     Z_GDU *gdu = search_package.response().get();
 683     if (!search_package.session().is_closed()
 684         && gdu && gdu->which == Z_GDU_Z3950
 685         && gdu->u.z3950->which == Z_APDU_searchResponse)
 686     {
 687         Z_SearchResponse *b_resp = gdu->u.z3950->u.searchResponse;
 688         *z_records = b_resp->records;
 689         m_result_set_size = *b_resp->resultCount;
 690
 691         additionalSearchInfoResponse = yaz_clone_z_OtherInformation(
 692             b_resp->additionalSearchInfo, mem_additionalSearchInfo);
 693         return true;
 694     }
 695     Z_APDU *f_apdu = 0;
 696     const char *addinfo = "session_shared: "
 697         "target closed connection during search";
 698     if (frontend_apdu->which == Z_APDU_searchRequest)
 699         f_apdu = odr.create_searchResponse(
 700             frontend_apdu, YAZ_BIB1_TEMPORARY_SYSTEM_ERROR, addinfo);
 701     else if (frontend_apdu->which == Z_APDU_presentRequest)
 702         f_apdu = odr.create_presentResponse(
 703             frontend_apdu, YAZ_BIB1_TEMPORARY_SYSTEM_ERROR, addinfo);
 704     else
 705         f_apdu = odr.create_close(
 706             frontend_apdu, YAZ_BIB1_TEMPORARY_SYSTEM_ERROR, addinfo);
 707     frontend_package.response() = f_apdu;
 708     return false;
 709 }
 710
 711 void yf::SessionShared::Frontend::override_set(
 712     BackendInstancePtr &found_backend,
 713     std::string &result_set_id,
 714     const Databases &databases,
 715     bool out_of_sessions)
 716 {
 717     BackendClassPtr bc = m_backend_class;
 718     BackendInstanceList::const_iterator it = bc->m_backend_list.begin();
 719     time_t now;
 720     time(&now);
 721
 722     size_t max_sets = bc->m_named_result_sets ? bc->m_backend_set_max : 1;
 723     for (; it != bc->m_backend_list.end(); it++)
 724     {
 725         if (!(*it)->m_in_use)
 726         {
 727             BackendSetList::iterator set_it = (*it)->m_sets.begin();
 728             for (; set_it != (*it)->m_sets.end(); set_it++)
 729             {
 730                 if ((max_sets > 1 || (*set_it)->m_databases == databases)
 731                     &&
 732                     (out_of_sessions ||
 733                      now < (*set_it)->m_time_last_use ||
 734                      now - (*set_it)->m_time_last_use >= bc->m_backend_set_ttl))
 735                 {
 736                     found_backend = *it;
 737                     result_set_id = (*set_it)->m_result_set_id;
 738                     found_backend->m_sets.erase(set_it);
 739                     return;
 740                 }
 741             }
 742         }
 743     }
 744     for (it = bc->m_backend_list.begin(); it != bc->m_backend_list.end(); it++)
 745     {
 746         if (!(*it)->m_in_use && (*it)->m_sets.size() < max_sets)
 747         {
 748             found_backend = *it;
 749             if (bc->m_named_result_sets)
 750             {
 751                 result_set_id = boost::io::str(
 752                     boost::format("%1%") %
 753                     found_backend->m_result_set_sequence);
 754                 found_backend->m_result_set_sequence++;
 755             }
 756             else
 757                 result_set_id = "default";
 758             return;
 759         }
 760     }
 761 }
 762
 763 void yf::SessionShared::Frontend::get_set(mp::Package &package,
 764                                           const Z_APDU *apdu_req,
 765                                           const Databases &databases,
 766                                           yazpp_1::Yaz_Z_Query &query,
 767                                           BackendInstancePtr &found_backend,
 768                                           BackendSetPtr &found_set)
 769 {
 770     bool session_restarted = false;
 771     Z_OtherInformation *additionalSearchInfo = 0;
 772
 773     if (apdu_req->which == Z_APDU_searchRequest)
 774         additionalSearchInfo = apdu_req->u.searchRequest->additionalSearchInfo;
 775
 776 restart:
 777     std::string result_set_id;
 778     bool out_of_sessions = false;
 779     BackendClassPtr bc = m_backend_class;
 780     {
 781         boost::mutex::scoped_lock lock(bc->m_mutex_backend_class);
 782
 783         if ((int) bc->m_backend_list.size() >= m_p->m_session_max)
 784             out_of_sessions = true;
 785
 786         if (m_p->m_optimize_search)
 787         {
 788             // look at each backend and see if we have a similar search
 789             BackendInstanceList::const_iterator it = bc->m_backend_list.begin();
 790             while (it != bc->m_backend_list.end())
 791             {
 792                 bool restart = false;
 793                 BackendSetList::const_iterator set_it = (*it)->m_sets.begin();
 794                 for (; set_it != (*it)->m_sets.end(); set_it++)
 795                 {
 796                     // for real present request we don't care
 797                     // if additionalSearchInfo matches: same records
 798                     if ((*set_it)->m_databases == databases
 799                         && query.match(&(*set_it)->m_query)
 800                         && (apdu_req->which != Z_APDU_searchRequest ||
 801                             yaz_compare_z_OtherInformation(
 802                                 additionalSearchInfo,
 803                                 (*set_it)->additionalSearchInfoRequest)))
 804                     {
 805                         if ((*it)->m_in_use)
 806                         {
 807                             bc->m_cond_set_ready.wait(lock);
 808                             restart = true;
 809                             break;
 810                         }
 811                         else
 812                         {
 813                             found_set = *set_it;
 814                             found_backend = *it;
 815                             bc->use_backend(found_backend);
 816                             // found matching set. No need to search again
 817                             return;
 818                         }
 819                     }
 820                 }
 821                 if (restart)
 822                     it = bc->m_backend_list.begin();
 823                 else
 824                     it++;
 825             }
 826         }
 827         override_set(found_backend, result_set_id, databases, out_of_sessions);
 828         if (found_backend)
 829             bc->use_backend(found_backend);
 830     }
 831     if (!found_backend)
 832     {
 833         // create a new backend set (and new set) if we're not out of sessions
 834         if (!out_of_sessions)
 835             found_backend = bc->create_backend(package);
 836
 837         if (!found_backend)
 838         {
 839             Z_APDU *f_apdu = 0;
 840             mp::odr odr;
 841             const char *addinfo = 0;
 842
 843             if (out_of_sessions)
 844                 addinfo = "session_shared: all sessions in use";
 845             else
 846                 addinfo = "session_shared: could not create backend";
 847             if (apdu_req->which == Z_APDU_searchRequest)
 848             {
 849                 f_apdu = odr.create_searchResponse(
 850                     apdu_req, YAZ_BIB1_TEMPORARY_SYSTEM_ERROR, addinfo);
 851             }
 852             else if (apdu_req->which == Z_APDU_presentRequest)
 853             {
 854                 f_apdu = odr.create_presentResponse(
 855                     apdu_req, YAZ_BIB1_TEMPORARY_SYSTEM_ERROR, addinfo);
 856             }
 857             else
 858             {
 859                 f_apdu = odr.create_close(
 860                     apdu_req, YAZ_BIB1_TEMPORARY_SYSTEM_ERROR, addinfo);
 861             }
 862             package.response() = f_apdu;
 863             return;
 864         }
 865         if (bc->m_named_result_sets)
 866         {
 867             result_set_id = boost::io::str(
 868                 boost::format("%1%") % found_backend->m_result_set_sequence);
 869             found_backend->m_result_set_sequence++;
 870         }
 871         else
 872             result_set_id = "default";
 873     }
 874     found_backend->timestamp();
 875
 876     // we must search ...
 877     BackendSetPtr new_set(new BackendSet(result_set_id,
 878                                          databases, query,
 879                                          additionalSearchInfo));
 880
 881     found_set = new_set;
 882     found_set->timestamp();
 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     found_backend->m_sets.push_back(found_set);
 962 }
 963
 964 int yf::SessionShared::Frontend::result_set_ref(ODR o,
 965                                                 const Databases &databases,
 966                                                 Z_RPNStructure *s,
 967                                                 std::string &rset)
 968 {
 969     int ret = 0;
 970     switch (s->which)
 971     {
 972     case Z_RPNStructure_simple:
 973         if (s->u.simple->which == Z_Operand_resultSetId)
 974         {
 975             const char *id = s->u.simple->u.resultSetId;
 976             rset = id;
 977
 978             FrontendSets::iterator fset_it = m_frontend_sets.find(id);
 979             if (fset_it == m_frontend_sets.end())
 980             {
 981                 ret = YAZ_BIB1_SPECIFIED_RESULT_SET_DOES_NOT_EXIST;
 982             }
 983             else if (fset_it->second->get_databases() != databases)
 984             {
 985                 ret = YAZ_BIB1_SPECIFIED_RESULT_SET_DOES_NOT_EXIST;
 986             }
 987             else
 988             {
 989                 yazpp_1::Yaz_Z_Query query = fset_it->second->get_query();
 990                 Z_Query *q = yaz_copy_Z_Query(query.get_Z_Query(), o);
 991                 if (q->which == Z_Query_type_1 || q->which == Z_Query_type_101)
 992                 {
 993                     s->which = q->u.type_1->RPNStructure->which;
 994                     s->u.simple = q->u.type_1->RPNStructure->u.simple;
 995                 }
 996                 else
 997                 {
 998                     ret = YAZ_BIB1_SPECIFIED_RESULT_SET_DOES_NOT_EXIST;
 999                 }
1000             }
1001         }
1002         break;
1003     case Z_RPNStructure_complex:
1004         ret = result_set_ref(o, databases, s->u.complex->s1, rset);
1005         if (!ret)
1006             ret = result_set_ref(o, databases, s->u.complex->s2, rset);
1007         break;
1008     }
1009     return ret;
1010 }
1011
1012 void yf::SessionShared::Frontend::search(mp::Package &package,
1013                                          Z_APDU *apdu_req)
1014 {
1015     Z_SearchRequest *req = apdu_req->u.searchRequest;
1016     FrontendSets::iterator fset_it =
1017         m_frontend_sets.find(req->resultSetName);
1018     if (fset_it != m_frontend_sets.end())
1019     {
1020         // result set already exist
1021         // if replace indicator is off: we return diagnostic if
1022         // result set already exist.
1023         if (*req->replaceIndicator == 0)
1024         {
1025             mp::odr odr;
1026             Z_APDU *apdu =
1027                 odr.create_searchResponse(
1028                     apdu_req,
1029                     YAZ_BIB1_RESULT_SET_EXISTS_AND_REPLACE_INDICATOR_OFF,
1030                     0);
1031             package.response() = apdu;
1032             return;
1033         }
1034         m_frontend_sets.erase(fset_it);
1035     }
1036
1037     Databases databases;
1038     int i;
1039     for (i = 0; i < req->num_databaseNames; i++)
1040         databases.push_back(req->databaseNames[i]);
1041
1042
1043     yazpp_1::Yaz_Z_Query query;
1044     query.set_Z_Query(req->query);
1045
1046     Z_Query *q = query.get_Z_Query();
1047     if (q->which == Z_Query_type_1 || q->which == Z_Query_type_101)
1048     {
1049         mp::odr odr;
1050         std::string rset;
1051         int diag = result_set_ref(odr, databases, q->u.type_1->RPNStructure,
1052                                   rset);
1053         if (diag)
1054         {
1055             Z_APDU *apdu =
1056                 odr.create_searchResponse(
1057                     apdu_req,
1058                     diag,
1059                     rset.c_str());
1060             package.response() = apdu;
1061             return;
1062         }
1063         query.set_Z_Query(q);
1064     }
1065
1066     BackendSetPtr found_set; // null
1067     BackendInstancePtr found_backend; // null
1068
1069     get_set(package, apdu_req, databases, query, found_backend, found_set);
1070     if (!found_set)
1071         return;
1072
1073     mp::odr odr;
1074     Z_APDU *f_apdu = odr.create_searchResponse(apdu_req, 0, 0);
1075     Z_SearchResponse *f_resp = f_apdu->u.searchResponse;
1076     *f_resp->resultCount = found_set->m_result_set_size;
1077     f_resp->additionalSearchInfo = found_set->additionalSearchInfoResponse;
1078     package.response() = f_apdu;
1079
1080     FrontendSetPtr fset(new FrontendSet(databases, query));
1081     m_frontend_sets[req->resultSetName] = fset;
1082
1083     m_backend_class->release_backend(found_backend);
1084 }
1085
1086 void yf::SessionShared::Frontend::present(mp::Package &package,
1087                                           Z_APDU *apdu_req)
1088 {
1089     mp::odr odr;
1090     Z_PresentRequest *req = apdu_req->u.presentRequest;
1091
1092     FrontendSets::iterator fset_it =
1093         m_frontend_sets.find(req->resultSetId);
1094
1095     if (fset_it == m_frontend_sets.end())
1096     {
1097         Z_APDU *apdu =
1098             odr.create_presentResponse(
1099                 apdu_req,
1100                 YAZ_BIB1_SPECIFIED_RESULT_SET_DOES_NOT_EXIST,
1101                 req->resultSetId);
1102         package.response() = apdu;
1103         return;
1104     }
1105     FrontendSetPtr fset = fset_it->second;
1106
1107     Databases databases = fset->get_databases();
1108     yazpp_1::Yaz_Z_Query query = fset->get_query();
1109
1110     BackendClassPtr bc = m_backend_class;
1111     BackendSetPtr found_set; // null
1112     BackendInstancePtr found_backend;
1113
1114     get_set(package, apdu_req, databases, query, found_backend, found_set);
1115     if (!found_set)
1116         return;
1117
1118     Z_NamePlusRecordList *npr_res = 0;
1119     // record_cache.lookup types are int's. Avoid non-fitting values
1120     if (*req->resultSetStartPoint > 0
1121         && *req->resultSetStartPoint < INT_MAX
1122         && *req->numberOfRecordsRequested > 0
1123         && *req->numberOfRecordsRequested < INT_MAX
1124         && found_set->m_record_cache.lookup(odr, &npr_res,
1125                                             *req->resultSetStartPoint,
1126                                             *req->numberOfRecordsRequested,
1127                                             req->preferredRecordSyntax,
1128                                             req->recordComposition))
1129     {
1130         Z_APDU *f_apdu_res = odr.create_presentResponse(apdu_req, 0, 0);
1131         Z_PresentResponse *f_resp = f_apdu_res->u.presentResponse;
1132
1133         yaz_log(YLOG_LOG, "Found " ODR_INT_PRINTF "+" ODR_INT_PRINTF
1134                 " records in cache %p",
1135                 *req->resultSetStartPoint,
1136                 *req->numberOfRecordsRequested,
1137                 &found_set->m_record_cache);
1138
1139         *f_resp->numberOfRecordsReturned = *req->numberOfRecordsRequested;
1140         *f_resp->nextResultSetPosition =
1141             *req->resultSetStartPoint + *req->numberOfRecordsRequested;
1142         // f_resp->presentStatus assumed OK.
1143         f_resp->records = (Z_Records *) odr_malloc(odr, sizeof(Z_Records));
1144         f_resp->records->which = Z_Records_DBOSD;
1145         f_resp->records->u.databaseOrSurDiagnostics = npr_res;
1146         package.response() = f_apdu_res;
1147         bc->release_backend(found_backend);
1148         return;
1149     }
1150
1151     found_backend->timestamp();
1152
1153     Z_APDU *p_apdu = zget_APDU(odr, Z_APDU_presentRequest);
1154     Z_PresentRequest *p_req = p_apdu->u.presentRequest;
1155     p_req->preferredRecordSyntax = req->preferredRecordSyntax;
1156     p_req->resultSetId = odr_strdup(odr, found_set->m_result_set_id.c_str());
1157     *p_req->resultSetStartPoint = *req->resultSetStartPoint;
1158     *p_req->numberOfRecordsRequested = *req->numberOfRecordsRequested;
1159     p_req->preferredRecordSyntax = req->preferredRecordSyntax;
1160     p_req->recordComposition = req->recordComposition;
1161
1162     Package present_package(found_backend->m_session, package.origin());
1163     present_package.copy_filter(package);
1164
1165     present_package.request() = p_apdu;
1166
1167     present_package.move();
1168
1169     Z_GDU *gdu = present_package.response().get();
1170     if (!present_package.session().is_closed()
1171         && gdu && gdu->which == Z_GDU_Z3950
1172         && gdu->u.z3950->which == Z_APDU_presentResponse)
1173     {
1174         Z_PresentResponse *b_resp = gdu->u.z3950->u.presentResponse;
1175         Z_APDU *f_apdu_res = odr.create_presentResponse(apdu_req, 0, 0);
1176         Z_PresentResponse *f_resp = f_apdu_res->u.presentResponse;
1177
1178         f_resp->numberOfRecordsReturned = b_resp->numberOfRecordsReturned;
1179         f_resp->nextResultSetPosition = b_resp->nextResultSetPosition;
1180         f_resp->presentStatus= b_resp->presentStatus;
1181         f_resp->records = b_resp->records;
1182         f_resp->otherInfo = b_resp->otherInfo;
1183         package.response() = f_apdu_res;
1184
1185         if (b_resp->records && b_resp->records->which ==  Z_Records_DBOSD)
1186         {
1187             Z_NamePlusRecordList *npr =
1188                 b_resp->records->u.databaseOrSurDiagnostics;
1189             // record_cache.add types are int's. Avoid non-fitting values
1190             if (*req->resultSetStartPoint > 0
1191                 && npr->num_records + *req->resultSetStartPoint < INT_MAX)
1192             {
1193 #if 0
1194                 yaz_log(YLOG_LOG, "Adding " ODR_INT_PRINTF "+" ODR_INT_PRINTF
1195                         " records to cache %p",
1196                         *req->resultSetStartPoint,
1197                         *f_resp->numberOfRecordsReturned,
1198                         &found_set->m_record_cache);
1199 #endif
1200                 found_set->m_record_cache.add(
1201                     odr, npr, *req->resultSetStartPoint,
1202                     p_req->recordComposition);
1203             }
1204         }
1205         bc->release_backend(found_backend);
1206     }
1207     else
1208     {
1209         bc->remove_backend(found_backend);
1210         Z_APDU *f_apdu_res =
1211             odr.create_presentResponse(
1212                 apdu_req, YAZ_BIB1_TEMPORARY_SYSTEM_ERROR,
1213                 "session_shared: target closed connection during present");
1214         package.response() = f_apdu_res;
1215     }
1216 }
1217
1218 void yf::SessionShared::Frontend::scan(mp::Package &frontend_package,
1219                                        Z_APDU *apdu_req)
1220 {
1221     BackendClassPtr bc = m_backend_class;
1222     BackendInstancePtr backend = bc->get_backend(frontend_package);
1223     if (!backend)
1224     {
1225         mp::odr odr;
1226         Z_APDU *apdu = odr.create_scanResponse(
1227             apdu_req, YAZ_BIB1_TEMPORARY_SYSTEM_ERROR,
1228             "session_shared: could not create backend");
1229         frontend_package.response() = apdu;
1230     }
1231     else
1232     {
1233         Package scan_package(backend->m_session, frontend_package.origin());
1234         backend->timestamp();
1235         scan_package.copy_filter(frontend_package);
1236         scan_package.request() = apdu_req;
1237         scan_package.move();
1238         frontend_package.response() = scan_package.response();
1239         if (scan_package.session().is_closed())
1240         {
1241             frontend_package.session().close();
1242             bc->remove_backend(backend);
1243         }
1244         else
1245             bc->release_backend(backend);
1246     }
1247 }
1248
1249 yf::SessionShared::Worker::Worker(SessionShared::Rep *rep) : m_p(rep)
1250 {
1251 }
1252
1253 void yf::SessionShared::Worker::operator() (void)
1254 {
1255     m_p->expire();
1256 }
1257
1258 bool yf::SessionShared::BackendClass::expire_instances()
1259 {
1260     time_t now;
1261     time(&now);
1262     boost::mutex::scoped_lock lock(m_mutex_backend_class);
1263     BackendInstanceList::iterator bit = m_backend_list.begin();
1264     while (bit != m_backend_list.end())
1265     {
1266         time_t last_use = (*bit)->m_time_last_use;
1267
1268         if ((*bit)->m_in_use)
1269         {
1270             bit++;
1271         }
1272         else if (now < last_use || now - last_use > m_backend_expiry_ttl)
1273         {
1274             bit = m_backend_list.erase(bit);
1275         }
1276         else
1277         {
1278             bit++;
1279         }
1280     }
1281     if (m_backend_list.empty())
1282         return true;
1283     return false;
1284 }
1285
1286 void yf::SessionShared::Rep::expire_classes()
1287 {
1288     boost::mutex::scoped_lock lock(m_mutex_backend_map);
1289     BackendClassMap::iterator b_it = m_backend_map.begin();
1290     while (b_it != m_backend_map.end())
1291     {
1292         if (b_it->second->expire_instances())
1293         {
1294             m_backend_map.erase(b_it);
1295             b_it = m_backend_map.begin();
1296         }
1297         else
1298             b_it++;
1299     }
1300 }
1301
1302 void yf::SessionShared::Rep::expire()
1303 {
1304     while (true)
1305     {
1306         boost::xtime xt;
1307         boost::xtime_get(&xt,
1308 #if BOOST_VERSION >= 105000
1309                 boost::TIME_UTC_
1310 #else
1311                 boost::TIME_UTC
1312 #endif
1313                   );
1314         xt.sec += m_session_ttl;
1315         {
1316             boost::mutex::scoped_lock lock(m_mutex);
1317             m_cond_expire_ready.timed_wait(lock, xt);
1318             if (close_down)
1319                 break;
1320         }
1321         stat();
1322         expire_classes();
1323     }
1324 }
1325
1326 yf::SessionShared::Rep::Rep()
1327 {
1328     m_resultset_ttl = 30;
1329     m_resultset_max = 10;
1330     m_session_ttl = 90;
1331     m_optimize_search = true;
1332     m_restart = false;
1333     m_session_max = 100;
1334     m_preferredMessageSize = 0;
1335     m_maximumRecordSize = 0;
1336     close_down = false;
1337 }
1338
1339 yf::SessionShared::Rep::~Rep()
1340 {
1341     {
1342         boost::mutex::scoped_lock lock(m_mutex);
1343         close_down = true;
1344         m_cond_expire_ready.notify_all();
1345     }
1346     m_thrds.join_all();
1347 }
1348
1349 void yf::SessionShared::Rep::start()
1350 {
1351     yf::SessionShared::Worker w(this);
1352     m_thrds.add_thread(new boost::thread(w));
1353 }
1354
1355 yf::SessionShared::SessionShared() : m_p(new SessionShared::Rep)
1356 {
1357 }
1358
1359 yf::SessionShared::~SessionShared() {
1360 }
1361
1362 void yf::SessionShared::start() const
1363 {
1364     m_p->start();
1365 }
1366
1367 yf::SessionShared::Frontend::Frontend(Rep *rep) : m_is_virtual(false), m_p(rep)
1368 {
1369 }
1370
1371 yf::SessionShared::Frontend::~Frontend()
1372 {
1373 }
1374
1375 yf::SessionShared::FrontendPtr yf::SessionShared::Rep::get_frontend(mp::Package &package)
1376 {
1377     boost::mutex::scoped_lock lock(m_mutex);
1378
1379     std::map<mp::Session,yf::SessionShared::FrontendPtr>::iterator it;
1380
1381     while(true)
1382     {
1383         it = m_clients.find(package.session());
1384         if (it == m_clients.end())
1385             break;
1386
1387         if (!it->second->m_in_use)
1388         {
1389             it->second->m_in_use = true;
1390             return it->second;
1391         }
1392         m_cond_session_ready.wait(lock);
1393     }
1394     FrontendPtr f(new Frontend(this));
1395     m_clients[package.session()] = f;
1396     f->m_in_use = true;
1397     return f;
1398 }
1399
1400 void yf::SessionShared::Rep::release_frontend(mp::Package &package)
1401 {
1402     boost::mutex::scoped_lock lock(m_mutex);
1403     std::map<mp::Session,yf::SessionShared::FrontendPtr>::iterator it;
1404
1405     it = m_clients.find(package.session());
1406     if (it != m_clients.end())
1407     {
1408         if (package.session().is_closed())
1409         {
1410             m_clients.erase(it);
1411         }
1412         else
1413         {
1414             it->second->m_in_use = false;
1415         }
1416         m_cond_session_ready.notify_all();
1417     }
1418 }
1419
1420
1421 void yf::SessionShared::process(mp::Package &package) const
1422 {
1423     FrontendPtr f = m_p->get_frontend(package);
1424
1425     Z_GDU *gdu = package.request().get();
1426
1427     if (gdu && gdu->which == Z_GDU_Z3950 && gdu->u.z3950->which ==
1428         Z_APDU_initRequest && !f->m_is_virtual)
1429     {
1430         m_p->init(package, gdu, f);
1431     }
1432     else if (!f->m_is_virtual)
1433         package.move();
1434     else if (gdu && gdu->which == Z_GDU_Z3950)
1435     {
1436         Z_APDU *apdu = gdu->u.z3950;
1437         if (apdu->which == Z_APDU_initRequest)
1438         {
1439             mp::odr odr;
1440
1441             package.response() = odr.create_close(
1442                 apdu,
1443                 Z_Close_protocolError,
1444                 "double init");
1445
1446             package.session().close();
1447         }
1448         else if (apdu->which == Z_APDU_close)
1449         {
1450             mp::odr odr;
1451
1452             package.response() = odr.create_close(
1453                 apdu,
1454                 Z_Close_peerAbort, "received close from client");
1455             package.session().close();
1456         }
1457         else if (apdu->which == Z_APDU_searchRequest)
1458         {
1459             f->search(package, apdu);
1460         }
1461         else if (apdu->which == Z_APDU_presentRequest)
1462         {
1463             f->present(package, apdu);
1464         }
1465         else if (apdu->which == Z_APDU_scanRequest)
1466         {
1467             f->scan(package, apdu);
1468         }
1469         else
1470         {
1471             mp::odr odr;
1472
1473             package.response() = odr.create_close(
1474                 apdu, Z_Close_protocolError,
1475                 "unsupported APDU in filter_session_shared");
1476
1477             package.session().close();
1478         }
1479     }
1480     m_p->release_frontend(package);
1481 }
1482
1483 void yf::SessionShared::configure(const xmlNode *ptr, bool test_only,
1484                                   const char *path)
1485 {
1486     for (ptr = ptr->children; ptr; ptr = ptr->next)
1487     {
1488         if (ptr->type != XML_ELEMENT_NODE)
1489             continue;
1490         if (!strcmp((const char *) ptr->name, "resultset"))
1491         {
1492             const struct _xmlAttr *attr;
1493             for (attr = ptr->properties; attr; attr = attr->next)
1494             {
1495                 if (!strcmp((const char *) attr->name, "ttl"))
1496                     m_p->m_resultset_ttl =
1497                         mp::xml::get_int(attr->children, 30);
1498                 else if (!strcmp((const char *) attr->name, "max"))
1499                 {
1500                     m_p->m_resultset_max =
1501                         mp::xml::get_int(attr->children, 10);
1502                 }
1503                 else if (!strcmp((const char *) attr->name, "optimizesearch"))
1504                 {
1505                     m_p->m_optimize_search =
1506                         mp::xml::get_bool(attr->children, true);
1507                 }
1508                 else if (!strcmp((const char *) attr->name, "restart"))
1509                 {
1510                     m_p->m_restart = mp::xml::get_bool(attr->children, true);
1511                 }
1512                 else
1513                     throw mp::filter::FilterException(
1514                         "Bad attribute " + std::string((const char *)
1515                                                        attr->name));
1516             }
1517         }
1518         else if (!strcmp((const char *) ptr->name, "session"))
1519         {
1520             const struct _xmlAttr *attr;
1521             for (attr = ptr->properties; attr; attr = attr->next)
1522             {
1523                 if (!strcmp((const char *) attr->name, "ttl"))
1524                     m_p->m_session_ttl =
1525                         mp::xml::get_int(attr->children, 90);
1526                 else if (!strcmp((const char *) attr->name, "max"))
1527                     m_p->m_session_max =
1528                         mp::xml::get_int(attr->children, 100);
1529                 else
1530                     throw mp::filter::FilterException(
1531                         "Bad attribute " + std::string((const char *)
1532                                                        attr->name));
1533             }
1534         }
1535         else if (!strcmp((const char *) ptr->name, "init"))
1536         {
1537             const struct _xmlAttr *attr;
1538             for (attr = ptr->properties; attr; attr = attr->next)
1539             {
1540                 if (!strcmp((const char *) attr->name, "maximum-record-size"))
1541                     m_p->m_maximumRecordSize =
1542                         mp::xml::get_int(attr->children, 0);
1543                 else if (!strcmp((const char *) attr->name,
1544                                  "preferred-message-size"))
1545                     m_p->m_preferredMessageSize =
1546                         mp::xml::get_int(attr->children, 0);
1547                 else
1548                     throw mp::filter::FilterException(
1549                         "Bad attribute " + std::string((const char *)
1550                                                        attr->name));
1551             }
1552         }
1553         else
1554         {
1555             throw mp::filter::FilterException("Bad element "
1556                                                + std::string((const char *)
1557                                                              ptr->name));
1558         }
1559     }
1560 }
1561
1562 static mp::filter::Base* filter_creator()
1563 {
1564     return new mp::filter::SessionShared;
1565 }
1566
1567 extern "C" {
1568     struct metaproxy_1_filter_struct metaproxy_1_filter_session_shared = {
1569         0,
1570         "session_shared",
1571         filter_creator
1572     };
1573 }
1574
1575 /*
1576  * Local variables:
1577  * c-basic-offset: 4
1578  * c-file-style: "Stroustrup"
1579  * indent-tabs-mode: nil
1580  * End:
1581  * vim: shiftwidth=4 tabstop=8 expandtab
1582  */
1583