--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Core/DicomNetworking/DicomStoreUserConnection.cpp	Fri Apr 10 16:04:54 2020 +0200
@@ -0,0 +1,237 @@
+/**
+ * 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 "DicomStoreUserConnection.h"
+
+#include "../Logging.h"
+#include "../OrthancException.h"
+
+namespace Orthanc
+{
+  bool DicomStoreUserConnection::ProposeStorageClass(const std::string& sopClassUid,
+                                                     const std::set<DicomTransferSyntax>& syntaxes)
+  {
+    size_t requiredCount = syntaxes.size();
+    if (proposeUncompressedSyntaxes_)
+    {
+      requiredCount += 1;
+    }
+      
+    if (association_.GetRemainingPropositions() <= requiredCount)
+    {
+      return false;  // Not enough room
+    }
+      
+    for (std::set<DicomTransferSyntax>::const_iterator
+           it = syntaxes.begin(); it != syntaxes.end(); ++it)
+    {
+      association_.ProposePresentationContext(sopClassUid, *it);
+    }
+
+    if (proposeUncompressedSyntaxes_)
+    {
+      std::set<DicomTransferSyntax> uncompressed;
+        
+      if (syntaxes.find(DicomTransferSyntax_LittleEndianImplicit) == syntaxes.end())
+      {
+        uncompressed.insert(DicomTransferSyntax_LittleEndianImplicit);
+      }
+        
+      if (syntaxes.find(DicomTransferSyntax_LittleEndianExplicit) == syntaxes.end())
+      {
+        uncompressed.insert(DicomTransferSyntax_LittleEndianExplicit);
+      }
+        
+      if (proposeRetiredBigEndian_ &&
+          syntaxes.find(DicomTransferSyntax_BigEndianExplicit) == syntaxes.end())
+      {
+        uncompressed.insert(DicomTransferSyntax_BigEndianExplicit);
+      }
+
+      if (!uncompressed.empty())
+      {
+        association_.ProposePresentationContext(sopClassUid, uncompressed);
+      }
+    }      
+
+    return true;
+  }
+
+
+  bool DicomStoreUserConnection::LookupPresentationContext(
+    uint8_t& presentationContextId,
+    const std::string& sopClassUid,
+    DicomTransferSyntax transferSyntax)
+  {
+    typedef std::map<DicomTransferSyntax, uint8_t>  PresentationContexts;
+
+    PresentationContexts pc;
+    if (association_.IsOpen() &&
+        association_.LookupAcceptedPresentationContext(pc, sopClassUid))
+    {
+      PresentationContexts::const_iterator found = pc.find(transferSyntax);
+      if (found != pc.end())
+      {
+        presentationContextId = found->second;
+        return true;
+      }
+    }
+
+    return false;
+  }
+    
+        
+  DicomStoreUserConnection::DicomStoreUserConnection(
+    const DicomAssociationParameters& params) :
+    parameters_(params),
+    proposeCommonClasses_(true),
+    proposeUncompressedSyntaxes_(true),
+    proposeRetiredBigEndian_(false)
+  {
+  }
+    
+
+  void DicomStoreUserConnection::PrepareStorageClass(const std::string& sopClassUid,
+                                                     DicomTransferSyntax syntax)
+  {
+    StorageClasses::iterator found = storageClasses_.find(sopClassUid);
+
+    if (found == storageClasses_.end())
+    {
+      std::set<DicomTransferSyntax> ts;
+      ts.insert(syntax);
+      storageClasses_[sopClassUid] = ts;
+    }
+    else
+    {
+      found->second.insert(syntax);
+    }
+  }
+
+
+  bool DicomStoreUserConnection::NegotiatePresentationContext(
+    uint8_t& presentationContextId,
+    const std::string& sopClassUid,
+    DicomTransferSyntax transferSyntax)
+  {
+    /**
+     * Step 1: Check whether this presentation context is already
+     * available in the previously negociated assocation.
+     **/
+
+    if (LookupPresentationContext(presentationContextId, sopClassUid, transferSyntax))
+    {
+      return true;
+    }
+
+    // The association must be re-negotiated
+    LOG(INFO) << "Re-negociating DICOM association with "
+              << parameters_.GetRemoteApplicationEntityTitle();
+    association_.ClearPresentationContexts();
+    PrepareStorageClass(sopClassUid, transferSyntax);
+
+      
+    /**
+     * Step 2: Propose at least the mandatory SOP class.
+     **/
+
+    {
+      StorageClasses::const_iterator mandatory = storageClasses_.find(sopClassUid);
+
+      if (mandatory == storageClasses_.end() ||
+          mandatory->second.find(transferSyntax) == mandatory->second.end())
+      {
+        throw OrthancException(ErrorCode_InternalError);
+      }
+
+      if (!ProposeStorageClass(sopClassUid, mandatory->second))
+      {
+        // Should never happen in real life: There are no more than
+        // 128 transfer syntaxes in DICOM!
+        throw OrthancException(ErrorCode_InternalError,
+                               "Too many transfer syntaxes for SOP class UID: " + sopClassUid);
+      }
+    }
+
+      
+    /**
+     * Step 3: Propose all the previously spotted SOP classes, as
+     * registered through the "PrepareStorageClass()" method.
+     **/
+      
+    for (StorageClasses::const_iterator it = storageClasses_.begin();
+         it != storageClasses_.end(); ++it)
+    {
+      if (it->first != sopClassUid)
+      {
+        ProposeStorageClass(it->first, it->second);
+      }
+    }
+      
+
+    /**
+     * Step 4: As long as there is room left in the proposed
+     * presentation contexts, propose the uncompressed transfer syntaxes
+     * for the most common SOP classes, as can be found in the
+     * "dcmShortSCUStorageSOPClassUIDs" array from DCMTK. The
+     * preferred transfer syntax is "LittleEndianImplicit".
+     **/
+
+    if (proposeCommonClasses_)
+    {
+      std::set<DicomTransferSyntax> ts;
+      ts.insert(DicomTransferSyntax_LittleEndianImplicit);
+        
+      for (int i = 0; i < numberOfDcmShortSCUStorageSOPClassUIDs; i++)
+      {
+        std::string c(dcmShortSCUStorageSOPClassUIDs[i]);
+          
+        if (c != sopClassUid &&
+            storageClasses_.find(c) == storageClasses_.end())
+        {
+          ProposeStorageClass(c, ts);
+        }
+      }
+    }
+
+
+    /**
+     * Step 5: Open the association, and check whether the pair (SOP
+     * class UID, transfer syntax) was accepted by the remote host.
+     **/
+
+    association_.Open(parameters_);
+    return LookupPresentationContext(presentationContextId, sopClassUid, transferSyntax);
+  }
+}