bool Tile::SerializeHeaderTo(SerializeOutput &output) {
  std::size_t start;

  // Use the cache if possible
  if (column_header != NULL) {
    PL_ASSERT(column_header_size != INVALID_OID);
    output.WriteBytes(column_header, column_header_size);
    return true;
  }

  PL_ASSERT(column_header_size == INVALID_OID);

  // Skip header position
  start = output.Position();
  output.WriteInt(-1);

  // Status code
  output.WriteByte(-128);

  // Column counts as a short
  output.WriteShort(static_cast<int16_t>(column_count));

  // Write an array of column types as bytes
  for (oid_t column_itr = 0; column_itr < column_count; ++column_itr) {
    type::Type::TypeId type = schema.GetType(column_itr);
    output.WriteByte(static_cast<int8_t>(type));
  }

  // Write the array of column names as strings
  // NOTE: strings are ASCII only in metadata (UTF-8 in table storage)
  for (oid_t column_itr = 0; column_itr < column_count; ++column_itr) {
    // Column name: Write (offset, length) for column definition, and string to
    // string table
    const std::string &name = GetColumnName(column_itr);

    // Column names can't be null, so length must be >= 0
    int32_t length = static_cast<int32_t>(name.size());
    PL_ASSERT(length >= 0);

    // this is standard string serialization for voltdb
    output.WriteInt(length);
    output.WriteBytes(name.data(), length);
  }

  // Write the header size which is a non-inclusive int
  size_t Position = output.Position();
  column_header_size = static_cast<int32_t>(Position - start);

  int32_t non_inclusive_header_size =
      static_cast<int32_t>(column_header_size - sizeof(int32_t));
  output.WriteIntAt(start, non_inclusive_header_size);

  // Cache the column header
  column_header = new char[column_header_size];
  PL_MEMCPY(column_header, static_cast<const char *>(output.Data()) + start,
            column_header_size);

  return true;
}
Exemple #2
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void VarlenType::SerializeTo(const Value &val, SerializeOutput &out) const {
  uint32_t len = GetLength(val);
  out.WriteInt(len);
  if (len > 0 && len < PELOTON_VALUE_NULL) {
    out.WriteBytes(val.GetData(), len);
  }
}