Method ResolveRegion

cpp/src/arrow/filesystem/s3fs.cc:1207–1220

  }

  Result<std::string> ResolveRegion(const std::string& bucket) {
    std::unique_lock<std::mutex> lock(cache_mutex_);
    auto it = cache_.find(bucket);
    if (it != cache_.end()) {
      return it->second;
    }
    // Cache miss: do the actual region lookup
    lock.unlock();
    ARROW_ASSIGN_OR_RAISE(auto region, ResolveRegionUncached(bucket));
    lock.lock();
    // Note we don't cache a nonexistent bucket, as the bucket could be created later
    cache_[bucket] = region;
    return region;
  }

  Result<std::string> ResolveRegionUncached(const std::string& bucket) {
    ARROW_ASSIGN_OR_RAISE(auto client_lock, holder_->Lock());