[EOS-CTA] Removes ServiceClientSide::Shutdown()

The implementation of Stop() is simply { return false; } so this
function is superfluous. It's not possible to shut down the service
on the client side except when completely closing down the client.

xroot_ssi_pb/XrdSsiPbService.hpp

@@ -45,6 +45,22 @@ public:
 #endif
             }
 
+   /*!
+    * Stop the Service.
+    *
+    * Requires some method to pass Finished(true) to in-flight Requests. This has been raised with Andy.
+    * Currently not implemented as it would require tracking all in-flight Requests by the application
+    * when this is really the job of the framework.
+    */
+
+   virtual bool Stop() override
+   {
+#ifdef XRDSSI_DEBUG
+      std::cout << "[DEBUG] Service::Stop()" << std::endl;
+#endif
+      return false;
+   }
+
    virtual void ProcessRequest(XrdSsiRequest &reqRef, XrdSsiResource &resRef) override;
 
    /*

xroot_ssi_pb/XrdSsiPbServiceClientSide.hpp

@@ -19,8 +19,6 @@
 #ifndef __XRD_SSI_PB_SERVICE_CLIENT_SIDE_H
 #define __XRD_SSI_PB_SERVICE_CLIENT_SIDE_H
 
-#include <unistd.h> // sleep()
-
 #include <XrdSsi/XrdSsiProvider.hh>
 #include <XrdSsi/XrdSsiService.hh>
 #include "XrdSsiPbException.hpp"
@@ -42,7 +40,6 @@ namespace XrdSsiPb {
 
 const unsigned int DefaultResponseBufferSize = 2097152;    //!< Default size for the response buffer in bytes = 2 Mb
 const unsigned int DefaultServerTimeout      = 15;         //!< Maximum XRootD reply timeout in secs
-const unsigned int DefaultShutdownTimeout    = 0;          //!< Maximum time to wait for the Service to shut down in secs
 
 
 
@@ -62,12 +59,9 @@ public:
 
    virtual ~ServiceClientSide();
 
-   bool Shutdown(int shutdown_tmo = DefaultShutdownTimeout);
-
    MetadataType Send(const RequestType &request);
 
 private:
-   bool           m_is_running;          //!< Is the service running?
    XrdSsiResource m_resource;            //!< Requests are bound to this resource. As the resource is
                                          //!< reusable, the lifetime of the resource is the same as the
                                          //!< lifetime of the Service object.
@@ -91,7 +85,6 @@ ServiceClientSide<RequestType, MetadataType, AlertType>::
 ServiceClientSide(const std::string &hostname, unsigned int port, const std::string &resource,
                           unsigned int response_bufsize,
                           unsigned int server_tmo) :
-   m_is_running(false),
    m_resource(resource),
    m_response_bufsize(response_bufsize),
    m_server_tmo(server_tmo)
@@ -126,8 +119,6 @@ ServiceClientSide(const std::string &hostname, unsigned int port, const std::str
    {
       throw XrdSsiException(eInfo);
    }
-
-   m_is_running = true;
 }
 
 
@@ -141,82 +132,16 @@ ServiceClientSide<RequestType, MetadataType, AlertType>::~ServiceClientSide()
 {
 #ifdef XRDSSI_DEBUG
    std::cout << "[DEBUG] ServiceClientSide() destructor" << std::endl;
-#endif
-
-#if 0
-   // Default Stop() implementation is return false;
-   // i.e. XRootD SSI makes no attempt to shut down!
-
-   // If the Service has not been shut down, make one last valiant effort to do so
-
-   if(m_is_running && !m_server_ptr->Stop())
-   {
-      std::cerr << "ServiceClientSide object was destroyed before all Requests have been processed. "
-                << "This will cause a memory leak. Call Shutdown() before deleting the object." << std::endl;
-   }
-#endif
-}
-
-
-
-/*!
- * Request Shutdown of the Service
- *
- * TODO: Define a Stop() method for the Service. Currently this method will always fail.
- *
- * A Service object can only be deleted after all requests handed to the object have completed. It is
- * possible to take back control of Requests by calling each Request's Finished() method: this cancels
- * the Request and the object can then be deleted.
- *
- * However, the current interface does not provide a way to recover a list of outstanding XrdSsi
- * Requests. I have raised this with Andy.
- *
- * @param[in]    shutdown_tmo    No. of seconds to wait before giving up
- *
- * @retval       true            The Service has been shut down
- * @retval       false           The Service has not been shut down
- */
-
-template <typename RequestType, typename MetadataType, typename AlertType>
-bool ServiceClientSide<RequestType, MetadataType, AlertType>::
-Shutdown(int shutdown_tmo)
-{
-   // Trivial case: server has already been shut down
-
-   if(!m_is_running) return true;
-
-#ifdef XRDSSI_DEBUG
-   std::cerr << "[DEBUG] ServiceClientSide::Shutdown():" << std::endl;
-   std::cerr << "Shutting down XRootD SSI service...";
-#endif
-
-   // The XrdSsiService object cannot be explicitly deleted. The Stop() method deletes the object if
-   // it is safe to do so.
-
-   while(!m_server_ptr->Stop() && shutdown_tmo--)
-   {
-      sleep(1);
-#ifdef XRDSSI_DEBUG
-      std::cerr << ".";
-#endif
-   }
 
-   if(shutdown_tmo > 0)
+   if(!m_server_ptr->Stop())
    {
-      m_is_running = false;
+      // As there is no way to get a list of in-flight Requests from the Service, the current Stop()
+      // implementation simply returns false. i.e. there is no way to know if we are shutting down
+      // cleanly or not.
 
-#ifdef XRDSSI_DEBUG
-      std::cerr << "done." << std::endl;
-#endif
+      std::cout << "[WARNING] ServiceClientSide object was destroyed before shutting down the Service." << std::endl;
    }
-   else
-   {
-#ifdef XRDSSI_DEBUG
-      std::cerr << "failed." << std::endl;
 #endif
-   }
-
-   return !m_is_running;
 }
 
 
@@ -228,13 +153,6 @@ Shutdown(int shutdown_tmo)
 template <typename RequestType, typename MetadataType, typename AlertType>
 MetadataType ServiceClientSide<RequestType, MetadataType, AlertType>::Send(const RequestType &request)
 {
-   // Check service is up
-
-   if(!m_is_running)
-   {
-      throw XrdSsiException("Service has been stopped");
-   }
-
    // Serialize the Request
 
    if(!request.SerializeToString(&m_request_str))