Properly lock Z39.50 sessions

[metaproxy-moved-to-github.git] / src / filter_z3950_client.cpp

diff --git a/src/filter_z3950_client.cpp b/src/filter_z3950_client.cpp
index db7a9fa..f0323dc 100644 (file)
--- a/src/filter_z3950_client.cpp
+++ b/src/filter_z3950_client.cpp
@@ -1,4 +1,4 @@
-/* $Id: filter_z3950_client.cpp,v 1.4 2005-10-25 16:01:14 adam Exp $
+/* $Id: filter_z3950_client.cpp,v 1.7 2005-10-30 16:39:18 adam Exp $
    Copyright (c) 2005, Index Data.
 
 %LICENSE%
@@ -6,11 +6,13 @@
 
 #include "config.hpp"
 
+#include <map>
 #include "filter.hpp"
 #include "router.hpp"
 #include "package.hpp"
 
 #include <boost/thread/mutex.hpp>
+#include <boost/thread/condition.hpp>
 
 #include "filter_z3950_client.hpp"
 
@@ -30,9 +32,9 @@ namespace yf = yp2::filter;
 namespace yp2 {
     namespace filter {
         class Z3950Client::Assoc : public yazpp_1::Z_Assoc{
-            friend class Pimpl;
+            friend class Rep;
         public:
-            Assoc(yp2::Session id, yazpp_1::SocketManager *socket_manager,
+            Assoc(yazpp_1::SocketManager *socket_manager,
                   yazpp_1::IPDU_Observable *PDU_Observable,
                   std::string host);
             ~Assoc();
@@ -44,36 +46,36 @@ namespace yp2 {
                 yazpp_1::IPDU_Observable *the_PDU_Observable,
                 int fd);
         private:
-            yp2::Session m_session_id;
+            // yp2::Session m_session_id;
             yazpp_1::SocketManager *m_socket_manager;
             yazpp_1::IPDU_Observable *m_PDU_Observable;
             Package *m_package;
+            bool m_in_use;
             bool m_waiting;
             bool m_connected;
             std::string m_host;
         };
 
-        class Z3950Client::Pimpl {
+        class Z3950Client::Rep {
         public:
             boost::mutex m_mutex;
-            std::list<Z3950Client::Assoc *> m_clients;
+            boost::condition m_cond_session_ready;
+            std::map<yp2::Session,Z3950Client::Assoc *> m_clients;
             Z3950Client::Assoc *get_assoc(Package &package);
             void send_and_receive(Package &package,
                                   yf::Z3950Client::Assoc *c);
-            void release_assoc(Package &package,
-                               yf::Z3950Client::Assoc *c);
+            void release_assoc(Package &package);
         };
     }
 }
 
 
-yf::Z3950Client::Assoc::Assoc(yp2::Session id,
-                              yazpp_1::SocketManager *socket_manager,
+yf::Z3950Client::Assoc::Assoc(yazpp_1::SocketManager *socket_manager,
                               yazpp_1::IPDU_Observable *PDU_Observable,
                               std::string host)
-    :  Z_Assoc(PDU_Observable), m_session_id(id),
+    :  Z_Assoc(PDU_Observable),
        m_socket_manager(socket_manager), m_PDU_Observable(PDU_Observable),
-       m_package(0), m_waiting(false), m_connected(false),
+       m_package(0), m_in_use(true), m_waiting(false), m_connected(false),
        m_host(host)
 {
     // std::cout << "create assoc " << this << "\n";
@@ -144,28 +146,33 @@ yazpp_1::IPDU_Observer *yf::Z3950Client::Assoc::sessionNotify(
 }
 
 
-yf::Z3950Client::Z3950Client() {
-    m_p = new yf::Z3950Client::Pimpl;
+yf::Z3950Client::Z3950Client() :  m_p(new yf::Z3950Client::Rep)
+{
 }
 
 yf::Z3950Client::~Z3950Client() {
-    delete m_p;
 }
 
-yf::Z3950Client::Assoc *yf::Z3950Client::Pimpl::get_assoc(Package &package) 
+yf::Z3950Client::Assoc *yf::Z3950Client::Rep::get_assoc(Package &package) 
 {
     // only one thread messes with the clients list at a time
     boost::mutex::scoped_lock lock(m_mutex);
 
-    std::list<yf::Z3950Client::Assoc *>::iterator it;
-
-    for (it = m_clients.begin(); it != m_clients.end(); it++)
+    std::map<yp2::Session,yf::Z3950Client::Assoc *>::iterator it;
+    
+    while(true)
     {
-        if ((*it)->m_session_id == package.session())
+        it = m_clients.find(package.session());
+        if (it == m_clients.end())
             break;
+        
+        if (!it->second->m_in_use)
+        {
+            it->second->m_in_use = true;
+            return it->second;
+        }
+        m_cond_session_ready.wait(lock);
     }
-    if (it != m_clients.end())
-        return *it;
 
     // only deal with Z39.50
     Z_GDU *gdu = package.request().get();
@@ -217,23 +224,19 @@ yf::Z3950Client::Assoc *yf::Z3950Client::Pimpl::get_assoc(Package &package)
     
     yazpp_1::SocketManager *sm = new yazpp_1::SocketManager;
     yazpp_1::PDU_Assoc *pdu_as = new yazpp_1::PDU_Assoc(sm);
-    yf::Z3950Client::Assoc *as = new yf::Z3950Client::Assoc(package.session(),
-                                                            sm, pdu_as,
-                                                            vhost);
-    m_clients.push_back(as);
+    yf::Z3950Client::Assoc *as = new yf::Z3950Client::Assoc(sm, pdu_as, vhost);
+    m_clients[package.session()] = as;
     return as;
 }
 
-void yf::Z3950Client::Pimpl::send_and_receive(Package &package,
-                                              yf::Z3950Client::Assoc *c)
+void yf::Z3950Client::Rep::send_and_receive(Package &package,
+                                            yf::Z3950Client::Assoc *c)
 {
     Z_GDU *gdu = package.request().get();
 
     if (!gdu || gdu->which != Z_GDU_Z3950)
         return;
 
-    // we should lock c!
-
     c->m_package = &package;
     c->m_waiting = true;
     if (!c->m_connected)
@@ -259,28 +262,28 @@ void yf::Z3950Client::Pimpl::send_and_receive(Package &package,
         ;
 }
 
-void yf::Z3950Client::Pimpl::release_assoc(Package &package,
-                                           yf::Z3950Client::Assoc *c)
+void yf::Z3950Client::Rep::release_assoc(Package &package)
 {
-    if (package.session().is_closed())
+    boost::mutex::scoped_lock lock(m_mutex);
+    std::map<yp2::Session,yf::Z3950Client::Assoc *>::iterator it;
+    
+    it = m_clients.find(package.session());
+    if (it != m_clients.end())
     {
-        boost::mutex::scoped_lock lock(m_mutex);
-        std::list<yf::Z3950Client::Assoc *>::iterator it;
-
-        for (it = m_clients.begin(); it != m_clients.end(); it++)
-        {
-            if ((*it)->m_session_id == package.session())
-                break;
-        }
-        if (it != m_clients.end())
+        if (package.session().is_closed())
         {
             // the Z_Assoc and PDU_Assoc must be destroyed before
             // the socket manager.. so pull that out.. first..
-            yazpp_1::SocketManager *s = (*it)->m_socket_manager;
-            delete *it;  // destroy Z_Assoc
+            yazpp_1::SocketManager *s = it->second->m_socket_manager;
+            delete it->second;  // destroy Z_Assoc
             delete s;    // then manager
             m_clients.erase(it);
         }
+        else
+        {
+            it->second->m_in_use = false;
+        }
+        m_cond_session_ready.notify_all();
     }
 }
 
@@ -290,8 +293,8 @@ void yf::Z3950Client::process(Package &package) const
     if (c)
     {
         m_p->send_and_receive(package, c);
-        m_p->release_assoc(package, c);
     }
+    m_p->release_assoc(package);
 }