mapnik/plugins/input/osm/dataset_deliverer.cpp

#include "dataset_deliverer.h"
#include "basiccurl.h"
#include <sstream>

osm_dataset * dataset_deliverer::dataset=NULL;
std::string dataset_deliverer::last_bbox = "";
std::string dataset_deliverer::last_filename = "";

osm_dataset* dataset_deliverer::load_from_file(const string& file,
                        const string& parser)
{
  // Only actually load from file if we haven't done so already
  if(dataset == NULL)
  {
    dataset = new osm_dataset;
    if(dataset->load(file.c_str(),parser)==false)
        return NULL;
    atexit(dataset_deliverer::release);
    last_filename = file;
  }
  else if(file != last_filename)
  {
    dataset = new osm_dataset;
    if(dataset->load(file.c_str(),parser)==false)
        return NULL;
    last_filename = file;
  }
  return dataset;
}

osm_dataset* dataset_deliverer::load_from_url
  (const string& url,const string& bbox,const string& parser)
{
  
  if(dataset==NULL)
  {
    dataset = new osm_dataset;
    if(dataset->load_from_url(url.c_str(),bbox,parser)==false)
      return NULL;
    atexit(dataset_deliverer::release);
    last_bbox = bbox;
  }
  else if (bbox != last_bbox)
  {
#ifdef MAPNIK_DEBUG
    cerr<<"BBOXES ARE DIFFERENT: " << last_bbox<<","<<bbox<<endl;
#endif

    // Reload the dataset  
    dataset->clear();
    if(dataset->load_from_url(url.c_str(),bbox,parser)==false)
      return NULL;
    last_bbox = bbox;  
  }
  return dataset;  
}