src/filter_z3950_client.cpp

   1 /* $Id: filter_z3950_client.cpp,v 1.16 2006-01-09 13:43:59 adam Exp $
   2    Copyright (c) 2005, Index Data.
   3
   4 %LICENSE%
   5  */
   6
   7 #include "config.hpp"
   8
   9 #include "filter.hpp"
  10 #include "router.hpp"
  11 #include "package.hpp"
  12 #include "util.hpp"
  13 #include "filter_z3950_client.hpp"
  14
  15 #include <map>
  16 #include <stdexcept>
  17 #include <list>
  18 #include <iostream>
  19
  20 #include <boost/thread/mutex.hpp>
  21 #include <boost/thread/condition.hpp>
  22
  23 #include <yaz/zgdu.h>
  24 #include <yaz/log.h>
  25 #include <yaz/otherinfo.h>
  26 #include <yaz/diagbib1.h>
  27
  28 #include <yaz++/socket-manager.h>
  29 #include <yaz++/pdu-assoc.h>
  30 #include <yaz++/z-assoc.h>
  31
  32 namespace yf = yp2::filter;
  33
  34 namespace yp2 {
  35     namespace filter {
  36         class Z3950Client::Assoc : public yazpp_1::Z_Assoc{
  37             friend class Rep;
  38             Assoc(yazpp_1::SocketManager *socket_manager,
  39                   yazpp_1::IPDU_Observable *PDU_Observable,
  40                   std::string host);
  41             ~Assoc();
  42             void connectNotify();
  43             void failNotify();
  44             void timeoutNotify();
  45             void recv_GDU(Z_GDU *gdu, int len);
  46             yazpp_1::IPDU_Observer* sessionNotify(
  47                 yazpp_1::IPDU_Observable *the_PDU_Observable,
  48                 int fd);
  49
  50             yazpp_1::SocketManager *m_socket_manager;
  51             yazpp_1::IPDU_Observable *m_PDU_Observable;
  52             Package *m_package;
  53             bool m_in_use;
  54             bool m_waiting;
  55             bool m_destroyed;
  56             bool m_connected;
  57             int m_queue_len;
  58             int m_ticks;
  59             std::string m_host;
  60         };
  61
  62         class Z3950Client::Rep {
  63         public:
  64             boost::mutex m_mutex;
  65             boost::condition m_cond_session_ready;
  66             std::map<yp2::Session,Z3950Client::Assoc *> m_clients;
  67             Z3950Client::Assoc *get_assoc(Package &package);
  68             void send_and_receive(Package &package,
  69                                   yf::Z3950Client::Assoc *c);
  70             void release_assoc(Package &package);
  71         };
  72     }
  73 }
  74
  75 using namespace yp2;
  76
  77 yf::Z3950Client::Assoc::Assoc(yazpp_1::SocketManager *socket_manager,
  78                               yazpp_1::IPDU_Observable *PDU_Observable,
  79                               std::string host)
  80     :  Z_Assoc(PDU_Observable),
  81        m_socket_manager(socket_manager), m_PDU_Observable(PDU_Observable),
  82        m_package(0), m_in_use(true), m_waiting(false),
  83        m_destroyed(false), m_connected(false), m_queue_len(1), m_ticks(0),
  84        m_host(host)
  85 {
  86     // std::cout << "create assoc " << this << "\n";
  87 }
  88
  89 yf::Z3950Client::Assoc::~Assoc()
  90 {
  91     // std::cout << "destroy assoc " << this << "\n";
  92 }
  93
  94 void yf::Z3950Client::Assoc::connectNotify()
  95 {
  96     m_waiting = false;
  97
  98     m_connected = true;
  99 }
 100
 101 void yf::Z3950Client::Assoc::failNotify()
 102 {
 103     m_waiting = false;
 104
 105     yp2::odr odr;
 106
 107     if (m_package)
 108     {
 109         m_package->response() = odr.create_close(Z_Close_peerAbort, 0);
 110         m_package->session().close();
 111     }
 112 }
 113
 114 void yf::Z3950Client::Assoc::timeoutNotify()
 115 {
 116     m_ticks++;
 117     if (m_ticks == 30)
 118     {
 119         m_waiting = false;
 120
 121         yp2::odr odr;
 122
 123         if (m_package)
 124         {
 125             if (m_connected)
 126                 m_package->response() = odr.create_close(Z_Close_lackOfActivity, 0);
 127             else
 128                 m_package->response() = odr.create_close(Z_Close_peerAbort, 0);
 129
 130             m_package->session().close();
 131         }
 132     }
 133 }
 134
 135 void yf::Z3950Client::Assoc::recv_GDU(Z_GDU *gdu, int len)
 136 {
 137     m_waiting = false;
 138
 139     if (m_package)
 140         m_package->response() = gdu;
 141 }
 142
 143 yazpp_1::IPDU_Observer *yf::Z3950Client::Assoc::sessionNotify(
 144     yazpp_1::IPDU_Observable *the_PDU_Observable,
 145     int fd)
 146 {
 147     return 0;
 148 }
 149
 150
 151 yf::Z3950Client::Z3950Client() :  m_p(new yf::Z3950Client::Rep)
 152 {
 153 }
 154
 155 yf::Z3950Client::~Z3950Client() {
 156 }
 157
 158 yf::Z3950Client::Assoc *yf::Z3950Client::Rep::get_assoc(Package &package)
 159 {
 160     // only one thread messes with the clients list at a time
 161     boost::mutex::scoped_lock lock(m_mutex);
 162
 163     std::map<yp2::Session,yf::Z3950Client::Assoc *>::iterator it;
 164
 165     Z_GDU *gdu = package.request().get();
 166     // only deal with Z39.50
 167     if (!gdu || gdu->which != Z_GDU_Z3950)
 168     {
 169         package.move();
 170         return 0;
 171     }
 172     it = m_clients.find(package.session());
 173     if (it != m_clients.end())
 174     {
 175         it->second->m_queue_len++;
 176         while(true)
 177         {
 178 #if 0
 179             if (gdu && gdu->which == Z_GDU_Z3950 &&
 180                 gdu->u.z3950->which == Z_APDU_initRequest)
 181             {
 182                 yazpp_1::SocketManager *s = it->second->m_socket_manager;
 183                 delete it->second;  // destroy Z_Assoc
 184                 delete s;    // then manager
 185                 m_clients.erase(it);
 186                 break;
 187             }
 188 #endif
 189             if (!it->second->m_in_use)
 190             {
 191                 it->second->m_in_use = true;
 192                 return it->second;
 193             }
 194             m_cond_session_ready.wait(lock);
 195         }
 196     }
 197     // new Z39.50 session ..
 198     Z_APDU *apdu = gdu->u.z3950;
 199     // check that it is init. If not, close
 200     if (apdu->which != Z_APDU_initRequest)
 201     {
 202         yp2::odr odr;
 203
 204         package.response() = odr.create_close(Z_Close_protocolError,
 205                                               "First PDU was not an "
 206                                               "Initialize Request");
 207         package.session().close();
 208         return 0;
 209     }
 210     // check virtual host
 211     const char *vhost =
 212         yaz_oi_get_string_oidval(&apdu->u.initRequest->otherInfo,
 213                                  VAL_PROXY, 1, 0);
 214     if (!vhost)
 215     {
 216         yp2::odr odr;
 217         package.response() = odr.create_initResponse(
 218             YAZ_BIB1_INIT_NEGOTIATION_OPTION_REQUIRED,
 219             "Virtual host not given");
 220
 221         package.session().close();
 222         return 0;
 223     }
 224
 225     yazpp_1::SocketManager *sm = new yazpp_1::SocketManager;
 226     yazpp_1::PDU_Assoc *pdu_as = new yazpp_1::PDU_Assoc(sm);
 227     yf::Z3950Client::Assoc *as = new yf::Z3950Client::Assoc(sm, pdu_as, vhost);
 228     m_clients[package.session()] = as;
 229     return as;
 230 }
 231
 232 void yf::Z3950Client::Rep::send_and_receive(Package &package,
 233                                             yf::Z3950Client::Assoc *c)
 234 {
 235     Z_GDU *gdu = package.request().get();
 236
 237     if (c->m_destroyed)
 238         return;
 239
 240     if (!gdu || gdu->which != Z_GDU_Z3950)
 241         return;
 242
 243     c->m_ticks = 0;
 244     c->m_package = &package;
 245     c->m_waiting = true;
 246     if (!c->m_connected)
 247     {
 248         c->client(c->m_host.c_str());
 249         c->timeout(1);
 250
 251         while (!c->m_destroyed && c->m_waiting
 252                && c->m_socket_manager->processEvent() > 0)
 253             ;
 254     }
 255     if (!c->m_connected)
 256     {
 257         return;
 258     }
 259
 260     // prepare response
 261     c->m_ticks = 0;
 262     c->m_waiting = true;
 263
 264     // relay the package  ..
 265     int len;
 266     c->send_GDU(gdu, &len);
 267
 268     switch(gdu->u.z3950->which)
 269     {
 270     case Z_APDU_triggerResourceControlRequest:
 271         // request only..
 272         break;
 273     default:
 274         // for the rest: wait for a response PDU
 275         while (!c->m_destroyed && c->m_waiting
 276                && c->m_socket_manager->processEvent() > 0)
 277             ;
 278         break;
 279     }
 280 }
 281
 282 void yf::Z3950Client::Rep::release_assoc(Package &package)
 283 {
 284     boost::mutex::scoped_lock lock(m_mutex);
 285     std::map<yp2::Session,yf::Z3950Client::Assoc *>::iterator it;
 286
 287     it = m_clients.find(package.session());
 288     if (it != m_clients.end())
 289     {
 290         Z_GDU *gdu = package.request().get();
 291         if (gdu && gdu->which == Z_GDU_Z3950)
 292         {   // only Z39.50 packages lock in get_assoc.. release it
 293             it->second->m_in_use = false;
 294             it->second->m_queue_len--;
 295         }
 296
 297         if (package.session().is_closed())
 298         {
 299             // destroy hint (send_and_receive)
 300             it->second->m_destroyed = true;
 301
 302             // wait until no one is waiting for it.
 303             while (it->second->m_queue_len)
 304                 m_cond_session_ready.wait(lock);
 305
 306             // the Z_Assoc and PDU_Assoc must be destroyed before
 307             // the socket manager.. so pull that out.. first..
 308             yazpp_1::SocketManager *s = it->second->m_socket_manager;
 309             delete it->second;  // destroy Z_Assoc
 310             delete s;    // then manager
 311             m_clients.erase(it);
 312         }
 313         m_cond_session_ready.notify_all();
 314     }
 315 }
 316
 317 void yf::Z3950Client::process(Package &package) const
 318 {
 319     yf::Z3950Client::Assoc *c = m_p->get_assoc(package);
 320     if (c)
 321     {
 322         m_p->send_and_receive(package, c);
 323     }
 324     m_p->release_assoc(package);
 325 }
 326
 327
 328 static yp2::filter::Base* filter_creator()
 329 {
 330     return new yp2::filter::Z3950Client;
 331 }
 332
 333 extern "C" {
 334     struct yp2_filter_struct yp2_filter_z3950_client = {
 335         0,
 336         "z3950_client",
 337         filter_creator
 338     };
 339 }
 340
 341 /*
 342  * Local variables:
 343  * c-basic-offset: 4
 344  * indent-tabs-mode: nil
 345  * c-file-style: "stroustrup"
 346  * End:
 347  * vim: shiftwidth=4 tabstop=8 expandtab
 348  */