SIOFrameData.h

Go to the documentation of this file.

#ifndef PODIO_SIOFRAMEDATA_H
#define PODIO_SIOFRAMEDATA_H
 
#include "podio/CollectionBuffers.h"
#include "podio/CollectionIDTable.h"
#include "podio/GenericParameters.h"
#include "podio/SIOBlock.h"
 
#include <sio/buffer.h>
#include <sio/definitions.h>
 
#include <memory>
#include <numeric>
#include <optional>
#include <string>
#include <vector>
 
namespace podio {
/**
 * The Frame data container for the SIO backend. It is constructed from the
 * compressed sio::buffers that is read from file and does all the necessary
 * unpacking and decompressing internally after construction.
 */
class SIOFrameData {
 
public:
  SIOFrameData() = delete;
  ~SIOFrameData() = default;
 
  SIOFrameData(const SIOFrameData&) = delete;
  SIOFrameData& operator=(const SIOFrameData&) = delete;
 
  SIOFrameData(SIOFrameData&&) = default;
  SIOFrameData& operator=(SIOFrameData&&) = default;
 
  /**
   * Constructor from the collBuffers containing the collection data and a
   * tableBuffer containing the necessary information for unpacking the
   * collections. The two size parameters denote the uncompressed size of the
   * respective buffers.
   */
  SIOFrameData(sio::buffer&& collBuffers, std::size_t dataSize, sio::buffer&& tableBuffer, std::size_t tableSize) :
      m_recBuffer(std::move(collBuffers)),
      m_tableBuffer(std::move(tableBuffer)),
      m_dataSize(dataSize),
      m_tableSize(tableSize) {
  }
 
  std::optional<podio::CollectionReadBuffers> getCollectionBuffers(const std::string& name);
 
  podio::CollectionIDTable getIDTable() {
    if (m_idTable.empty()) {
      readIdTable();
    }
    return {m_idTable.ids(), m_idTable.names()};
  }
 
  std::unique_ptr<podio::GenericParameters> getParameters();
 
  std::vector<std::string> getAvailableCollections();
 
private:
  void unpackBuffers();
 
  void readIdTable();
 
  void createBlocks();
 
  // Default initialization doesn't really matter here, because they are made
  // the correct size on construction
  sio::buffer m_recBuffer{sio::kbyte};   ///< The compressed record (data) buffer
  sio::buffer m_tableBuffer{sio::kbyte}; ///< The compressed collection id table buffer
 
  std::size_t m_dataSize{};  ///< Uncompressed data buffer size
  std::size_t m_tableSize{}; ///< Uncompressed table size
 
  std::vector<short> m_availableBlocks{}; ///< The blocks that have already been retrieved
 
  sio::block_list m_blocks{};
 
  podio::CollectionIDTable m_idTable{};
  std::vector<std::string> m_typeNames{};
  std::vector<short> m_subsetCollectionBits{};
 
  podio::GenericParameters m_parameters{};
};
} // namespace podio
 
#endif // PODIO_SIOFRAMEDATA_H