Method EnsureInitialized

cpp/src/arrow/acero/tpch_node.cc:281–314

static TpchPseudotext g_text;

Status TpchPseudotext::EnsureInitialized(random::pcg32_fast& rng) {
  if (done_.load()) return Status::OK();

  {
    std::lock_guard<std::mutex> lock(text_guard_);
    if (!text_) {
      ARROW_ASSIGN_OR_RAISE(text_, AllocateBuffer(kTextBytes));
    }
  }
  char* out = reinterpret_cast<char*>(text_->mutable_data());
  char temp_buff[kChunkSize];

  while (!done_.load()) {
    int64_t known_valid_offset = 0;
    int64_t try_offset = 0;
    while (GenerateSentence(try_offset, rng, temp_buff)) known_valid_offset = try_offset;

    bool last_one;
    int64_t offset;
    int64_t memcpy_size;
    {
      std::lock_guard<std::mutex> lock(text_guard_);
      if (done_.load()) return Status::OK();
      int64_t bytes_remaining = kTextBytes - generated_offset_;
      memcpy_size = std::min(known_valid_offset, bytes_remaining);
      offset = generated_offset_;
      generated_offset_ += memcpy_size;
      last_one = generated_offset_ == kTextBytes;
    }
    std::memcpy(out + offset, temp_buff, memcpy_size);
    if (last_one) done_.store(true);
  }
  return Status::OK();
}

Result<Datum> TpchPseudotext::GenerateComments(size_t num_comments, size_t min_length,
                                               size_t max_length,