--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/OrthancFramework/Sources/Cache/SharedArchive.cpp	Wed Jun 10 20:30:34 2020 +0200
@@ -0,0 +1,149 @@
+/**
+ * Orthanc - A Lightweight, RESTful DICOM Store
+ * Copyright (C) 2012-2016 Sebastien Jodogne, Medical Physics
+ * Department, University Hospital of Liege, Belgium
+ * Copyright (C) 2017-2020 Osimis S.A., Belgium
+ *
+ * This program is free software: you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * In addition, as a special exception, the copyright holders of this
+ * program give permission to link the code of its release with the
+ * OpenSSL project's "OpenSSL" library (or with modified versions of it
+ * that use the same license as the "OpenSSL" library), and distribute
+ * the linked executables. You must obey the GNU General Public License
+ * in all respects for all of the code used other than "OpenSSL". If you
+ * modify file(s) with this exception, you may extend this exception to
+ * your version of the file(s), but you are not obligated to do so. If
+ * you do not wish to do so, delete this exception statement from your
+ * version. If you delete this exception statement from all source files
+ * in the program, then also delete it here.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ **/
+
+
+#include "../PrecompiledHeaders.h"
+#include "SharedArchive.h"
+
+#include "../Toolbox.h"
+
+
+namespace Orthanc
+{
+  void SharedArchive::RemoveInternal(const std::string& id)
+  {
+    Archive::iterator it = archive_.find(id);
+
+    if (it != archive_.end())
+    {
+      delete it->second;
+      archive_.erase(it);
+
+      lru_.Invalidate(id);
+    }
+  }
+
+
+  SharedArchive::Accessor::Accessor(SharedArchive& that,
+                                    const std::string& id) :
+    lock_(that.mutex_)
+  {
+    Archive::iterator it = that.archive_.find(id);
+
+    if (it == that.archive_.end())
+    {
+      item_ = NULL;
+    }
+    else
+    {
+      that.lru_.MakeMostRecent(id);
+      item_ = it->second;
+    }
+  }
+
+
+  IDynamicObject& SharedArchive::Accessor::GetItem() const
+  {
+    if (item_ == NULL)
+    {
+      // "IsValid()" should have been called
+      throw OrthancException(ErrorCode_BadSequenceOfCalls);
+    }
+    else
+    {
+      return *item_;
+    }
+  }  
+
+
+  SharedArchive::SharedArchive(size_t maxSize) : 
+    maxSize_(maxSize)
+  {
+    if (maxSize == 0)
+    {
+      throw OrthancException(ErrorCode_ParameterOutOfRange);
+    }
+  }
+
+
+  SharedArchive::~SharedArchive()
+  {
+    for (Archive::iterator it = archive_.begin();
+         it != archive_.end(); ++it)
+    {
+      delete it->second;
+    }
+  }
+
+
+  std::string SharedArchive::Add(IDynamicObject* obj)
+  {
+    boost::mutex::scoped_lock lock(mutex_);
+
+    if (archive_.size() == maxSize_)
+    {
+      // The quota has been reached, remove the oldest element
+      RemoveInternal(lru_.GetOldest());
+    }
+
+    std::string id = Toolbox::GenerateUuid();
+    RemoveInternal(id);  // Should never be useful because of UUID
+
+    archive_[id] = obj;
+    lru_.Add(id);
+
+    return id;
+  }
+
+
+  void SharedArchive::Remove(const std::string& id)
+  {
+    boost::mutex::scoped_lock lock(mutex_);
+    RemoveInternal(id);      
+  }
+
+
+  void SharedArchive::List(std::list<std::string>& items)
+  {
+    items.clear();
+
+    {
+      boost::mutex::scoped_lock lock(mutex_);
+
+      for (Archive::const_iterator it = archive_.begin();
+           it != archive_.end(); ++it)
+      {
+        items.push_back(it->first);
+      }
+    }
+  }
+}