HDFS-9265. InputStreamImpl should hold a shared_ptr of the BlockReader. Contributed by James Clampffer.

hadoop-hdfs-project/hadoop-hdfs-native-client/src/main/native/libhdfspp/lib/fs/inputstream_impl.h

@@ -33,7 +33,7 @@ struct InputStreamImpl::RemoteBlockReaderTrait {
   typedef RemoteBlockReader<asio::ip::tcp::socket> Reader;
   struct State {
     std::unique_ptr<asio::ip::tcp::socket> conn_;
-    std::unique_ptr<Reader> reader_;
+    std::shared_ptr<Reader> reader_;
     std::array<asio::ip::tcp::endpoint, 1> endpoints_;
     size_t transferred_;
     Reader *reader() { return reader_.get(); }
@@ -47,7 +47,7 @@ struct InputStreamImpl::RemoteBlockReaderTrait {
     auto m = continuation::Pipeline<State>::Create();
     auto &s = m->state();
     s.conn_.reset(new tcp::socket(*io_service));
-    s.reader_.reset(new Reader(BlockReaderOptions(), s.conn_.get()));
+    s.reader_ = std::make_shared<Reader>(BlockReaderOptions(), s.conn_.get());
     auto datanode = dn.id();
     s.endpoints_[0] = tcp::endpoint(address::from_string(datanode.ipaddr()),
                                     datanode.xferport());