From 737a2a0aa96ff67db7cd09a11fdb2883a84d1233 Mon Sep 17 00:00:00 2001
From: Christopher Kohlhoff <chris@kohlhoff.com>
Date: Sun, 17 Oct 2021 11:05:21 +1100
Subject: [PATCH] Don't use shared_ptr in basic_socket_streambuf
 implementation.

---
 include/boost/asio/basic_socket_streambuf.hpp | 26 ++++++++++++++++---
 1 file changed, 23 insertions(+), 3 deletions(-)

diff --git a/include/boost/asio/basic_socket_streambuf.hpp b/include/boost/asio/basic_socket_streambuf.hpp
index bd9c8d8d..3da96233 100644
--- a/include/boost/asio/basic_socket_streambuf.hpp
+++ b/include/boost/asio/basic_socket_streambuf.hpp
@@ -24,7 +24,6 @@
 #include <boost/asio/basic_socket.hpp>
 #include <boost/asio/basic_stream_socket.hpp>
 #include <boost/asio/detail/buffer_sequence_adapter.hpp>
-#include <boost/asio/detail/memory.hpp>
 #include <boost/asio/detail/throw_error.hpp>
 #include <boost/asio/io_context.hpp>
 
@@ -85,7 +84,28 @@ protected:
   {
   }
 
-  shared_ptr<io_context> default_io_context_;
+#if defined(BOOST_ASIO_HAS_MOVE)
+  socket_streambuf_io_context(socket_streambuf_io_context&& other)
+    : default_io_context_(other.default_io_context_)
+  {
+    other.default_io_context_ = 0;
+  }
+
+  socket_streambuf_io_context& operator=(socket_streambuf_io_context&& other)
+  {
+    delete default_io_context_;
+    default_io_context_ = other.default_io_context_;
+    other.default_io_context_ = 0;
+    return *this;
+  }
+#endif // defined(BOOST_ASIO_HAS_MOVE)
+
+  io_context* default_io_context_;
+
+private:
+  // Disallow copying and assignment.
+  socket_streambuf_io_context(const socket_streambuf_io_context&);
+  socket_streambuf_io_context& operator=(const socket_streambuf_io_context&);
 };
 
 // A separate base class is used to ensure that the dynamically allocated
@@ -229,7 +249,7 @@ public:
   {
     this->close();
     socket() = std::move(other.socket());
-    detail::socket_streambuf_io_context::operator=(other);
+    detail::socket_streambuf_io_context::operator=(std::move(other));
     ec_ = other.ec_;
     expiry_time_ = other.expiry_time_;
     get_buffer_.swap(other.get_buffer_);