qdp_map_obj_disk.cc

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#include "qdp_map_obj_disk.h"
 
#include <errno.h>
#include <sys/stat.h>
 
namespace QDP 
{ 
  namespace MapObjDiskEnv 
  {
    // Anonymous namespace
    namespace {
      const std::string file_magic="XXXXQDPLazyDiskMapObjFileXXXX";
    };
 
    // Magic string at start of file.
    std::string getFileMagic() {return file_magic;}
 
    // Get meta-data
    std::string getMetaData(const std::string& filename)
    {
      BinaryFileReader reader;
      reader.open(filename);
 
      std::string read_magic;
      reader.readDesc(read_magic);
    
      // Check magic
      if (read_magic != MapObjDiskEnv::file_magic) { 
        QDPIO::cerr << "Magic String Wrong: Expected: " << MapObjDiskEnv::file_magic << " but read: " << read_magic << std::endl;
        QDP_abort(1);
      }
 
      MapObjDiskEnv::file_version_t read_version;
      read(reader, read_version);
      
      std::string user_data;
      readDesc(reader, user_data);
    
      reader.close();
      return user_data;
    }
 
 
    // Check for a file
    bool checkForNewFile(const std::string& file, std::ios_base::openmode mode)
    {
      bool new_file = false;
 
      if (Layout::primaryNode()) 
      {
        struct stat statbuf;
        if ((mode & std::ios_base::trunc) || (stat(file.c_str(), &statbuf) != 0 && (errno == ENOENT)))
        {
          if (errno == ENOENT)
            errno = 0;  /* In case someone looks at errno. */
          new_file = true;
        }
      }
 
      QDPInternal::broadcast(new_file);
 
      return new_file;
    }
  }
    
}