Method registerModule

Libs/CommandLineModules/Core/ctkCmdLineModuleManager.cpp:183–331

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//----------------------------------------------------------------------------
ctkCmdLineModuleReference
ctkCmdLineModuleManager::registerModule(const QUrl &location)
{
  QByteArray xml;
  ctkCmdLineModuleBackend* backend = NULL;
  {
    QMutexLocker lock(&d->Mutex);

    d->checkBackends_unlocked(location);

    // If the module is already registered, just return the reference
    if (d->LocationToRef.contains(location))
    {
      return d->LocationToRef[location];
    }

    backend = d->SchemeToBackend[location.scheme()];
  }

  bool fromCache = false;
  qint64 newTimeStamp = 0;
  qint64 cacheTimeStamp = 0;
  int timeout = backend->timeOutForXmlRetrieval();
  if (timeout == 0)
  {
    timeout = d->XmlTimeOut;
  }

  if (d->ModuleCache)
  {
    newTimeStamp = backend->timeStamp(location);
    cacheTimeStamp = d->ModuleCache->timeStamp(location);
    if (cacheTimeStamp < 0                // i.e. timestamp is invalid
        || cacheTimeStamp < newTimeStamp) // i.e. timestamp is genuinely out of date
    {
      // newly fetch the XML description
      try
      {
        xml = backend->rawXmlDescription(location, timeout);
      }
      catch (const ctkCmdLineModuleTimeoutException&)
      {
        // in case of a time-out, do not cache it as a failed attempt
        // by recording an empty QByteArray in the cache
        throw;
      }
      catch (...)
      {
        // cache the failed attempt
        d->ModuleCache->cacheXmlDescription(location, newTimeStamp, QByteArray());
        throw;
      }
    }
    else
    {
      // use the cached XML description
      xml = d->ModuleCache->rawXmlDescription(location);
      fromCache = true;