podio::SIOWriter Class Reference

#include <SIOWriter.h>

Public Member Functions
	SIOWriter (const std::string &filename, EventStore *store)
	~SIOWriter ()=default
	SIOWriter (const SIOWriter &)=delete
SIOWriter &	operator= (const SIOWriter &)=delete
void	registerForWrite (const std::string &name)
void	writeEvent ()
void	finish ()

Detailed Description

Definition at line 19 of file SIOWriter.h.

Constructor & Destructor Documentation

SIOWriter() [1/2]

podio::SIOWriter::SIOWriter	(	const std::string &	filename,
		EventStore *	store
	)

Definition at line 15 of file SIOWriter.cc.

                                                                 :
    m_filename(filename),
    m_store(store),
    m_eventMetaData(std::make_shared<SIOEventMetaDataBlock>()),
    m_runMetaData(std::make_shared<SIONumberedMetaDataBlock>("RunMetaData")),
    m_collectionMetaData(std::make_shared<SIONumberedMetaDataBlock>("CollectionMetaData")) {
 
  m_stream.open(filename, std::ios::binary);
 
  if (not m_stream.is_open()) {
    SIO_THROW(sio::error_code::not_open, "Couldn't open output stream '" + filename + "'");
  }
 
  // TODO: re-visit this once metadata handling is done in better defined way
  m_eventMetaData->metadata = m_store->eventMetaDataPtr();
 
  m_runMetaData->data = m_store->getRunMetaDataMap();
  m_collectionMetaData->data = m_store->getColMetaDataMap();
 
  auto& libLoader [[maybe_unused]] = SIOBlockLibraryLoader::instance();
}

~SIOWriter()

podio::SIOWriter::~SIOWriter ( )

default

SIOWriter() [2/2]

podio::SIOWriter::SIOWriter ( const SIOWriter &  )

delete

Member Function Documentation

finish()

void podio::SIOWriter::finish

(

)

Definition at line 65 of file SIOWriter.cc.

                       {
  sio::block_list blocks{};
  blocks.push_back(m_runMetaData);
 
  m_tocRecord.addRecord(m_runMetaData->name(), sio_utils::writeRecord(blocks, m_runMetaData->name(), m_stream));
 
  blocks.clear();
  blocks.push_back(m_collectionMetaData);
  m_tocRecord.addRecord(m_collectionMetaData->name(),
                        sio_utils::writeRecord(blocks, m_collectionMetaData->name(), m_stream));
 
  blocks.clear();
  auto tocRecordBlock = std::make_shared<SIOFileTOCRecordBlock>();
  tocRecordBlock->record = &m_tocRecord;
  blocks.push_back(tocRecordBlock);
 
  const auto tocStartPos = sio_utils::writeRecord(blocks, sio_helpers::SIOTocRecordName, m_stream);
  // Now that we know the position of the TOC Record, put this information
  // into a final marker that can be identified and interpreted when reading
  // again
  uint64_t finalWords = (((uint64_t)sio_helpers::SIOTocMarker) << 32) | ((uint64_t)tocStartPos & 0xffffffff);
  m_stream.write(reinterpret_cast<char*>(&finalWords), sizeof(finalWords));
 
  m_stream.close();
}

operator=()

SIOWriter & podio::SIOWriter::operator= ( const SIOWriter &  )

delete

registerForWrite()

void podio::SIOWriter::registerForWrite

(

const std::string &

name

)

Definition at line 91 of file SIOWriter.cc.

                                                      {
 
  const podio::CollectionBase* colB(nullptr);
  m_store->get(name, colB);
 
  if (!colB) {
    throw std::runtime_error(std::string("no such collection to write: ") + name);
  }
  // Check if we can instantiate the blocks here so that we can skip the checks later
  if (auto blk = podio::SIOBlockFactory::instance().createBlock(colB, name); !blk) {
    const auto typName = colB->getValueTypeName();
    throw std::runtime_error(std::string("could not create SIOBlock for type: ") + typName);
  }
 
  m_collectionsToWrite.push_back(name);
}

writeEvent()

void podio::SIOWriter::writeEvent

(

)

Definition at line 37 of file SIOWriter.cc.

                           {
  if (m_firstEvent) {
    // Write the collectionIDs as a separate record at the beginning of the
    // file. In this way they can easily be retrieved in the SIOReader without
    // having to look for this specific record.
    writeCollectionIDTable();
    m_firstEvent = false;
  }
 
  auto blocks = createBlocks();
  m_tocRecord.addRecord("event_record", sio_utils::writeRecord(blocks, "event_record", m_stream));
}

---

The documentation for this class was generated from the following files:

• SIOWriter.h
• SIOWriter.cc