--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/OrthancFramework/Sources/SharedLibrary.cpp	Wed Jun 10 20:30:34 2020 +0200
@@ -0,0 +1,154 @@
+/**
+ * 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 "SharedLibrary.h"
+
+#include "Logging.h"
+#include "OrthancException.h"
+
+#include <boost/filesystem.hpp>
+
+#if defined(_WIN32)
+#include <windows.h>
+#elif defined(__linux__) || (defined(__APPLE__) && defined(__MACH__)) || defined(__FreeBSD_kernel__) || defined(__FreeBSD__) || defined(__OpenBSD__)
+#include <dlfcn.h>
+#else
+#error Support your platform here
+#endif
+
+namespace Orthanc
+{
+  SharedLibrary::SharedLibrary(const std::string& path) : 
+    path_(path), 
+    handle_(NULL)
+  {
+#if defined(_WIN32)
+    handle_ = ::LoadLibraryA(path_.c_str());
+    if (handle_ == NULL)
+    {
+      LOG(ERROR) << "LoadLibrary(" << path_ << ") failed: Error " << ::GetLastError();
+      throw OrthancException(ErrorCode_SharedLibrary);
+    }
+
+#elif defined(__linux__) || (defined(__APPLE__) && defined(__MACH__)) || defined(__FreeBSD_kernel__) || defined(__FreeBSD__) || defined(__OpenBSD__)
+   
+    /**
+     * "RTLD_LOCAL" is the default, and is only present to be
+     * explicit. "RTLD_DEEPBIND" was added in Orthanc 1.6.0, in order
+     * to avoid crashes while loading plugins from the LSB binaries of
+     * the Orthanc core.
+     *
+     * BUT this had no effect, and this results in a crash if loading
+     * the Python 2.7 plugin => We disabled it again in Orthanc 1.6.1.
+     **/
+    
+#if 0 // && defined(RTLD_DEEPBIND)  // This is a GNU extension
+    // Disabled in Orthanc 1.6.1
+    handle_ = ::dlopen(path_.c_str(), RTLD_NOW | RTLD_LOCAL | RTLD_DEEPBIND);
+#else
+    handle_ = ::dlopen(path_.c_str(), RTLD_NOW | RTLD_LOCAL);
+#endif
+
+    if (handle_ == NULL) 
+    {
+      std::string explanation;
+      const char *tmp = ::dlerror();
+      if (tmp)
+      {
+        explanation = ": Error " + std::string(tmp);
+      }
+
+      LOG(ERROR) << "dlopen(" << path_ << ") failed" << explanation;
+      throw OrthancException(ErrorCode_SharedLibrary);
+    }
+
+#else
+#error Support your platform here
+#endif   
+  }
+
+  SharedLibrary::~SharedLibrary()
+  {
+    if (handle_)
+    {
+#if defined(_WIN32)
+      ::FreeLibrary((HMODULE)handle_);
+#elif defined(__linux__) || (defined(__APPLE__) && defined(__MACH__)) || defined(__FreeBSD_kernel__) || defined(__FreeBSD__) || defined(__OpenBSD__)
+      ::dlclose(handle_);
+#else
+#error Support your platform here
+#endif
+    }
+  }
+
+
+  SharedLibrary::FunctionPointer SharedLibrary::GetFunctionInternal(const std::string& name)
+  {
+    if (!handle_)
+    {
+      throw OrthancException(ErrorCode_InternalError);
+    }
+
+#if defined(_WIN32)
+    return ::GetProcAddress((HMODULE)handle_, name.c_str());
+#elif defined(__linux__) || (defined(__APPLE__) && defined(__MACH__)) || defined(__FreeBSD_kernel__) || defined(__FreeBSD__) || defined(__OpenBSD__)
+    return ::dlsym(handle_, name.c_str());
+#else
+#error Support your platform here
+#endif
+  }
+
+
+  SharedLibrary::FunctionPointer SharedLibrary::GetFunction(const std::string& name)
+  {
+    SharedLibrary::FunctionPointer result = GetFunctionInternal(name);
+  
+    if (result == NULL)
+    {
+      throw OrthancException(
+        ErrorCode_SharedLibrary,
+        "Shared library does not expose function \"" + name + "\"");
+    }
+    else
+    {
+      return result;
+    }
+  }
+
+
+  bool SharedLibrary::HasFunction(const std::string& name)
+  {
+    return GetFunctionInternal(name) != NULL;
+  }
+}