[Boost-bugs] [Boost C++ Libraries] #3958: ssl::stream async_read_some and async_write_some handlers never run concurrently

Subject: [Boost-bugs] [Boost C++ Libraries] #3958: ssl::stream async_read_some and async_write_some handlers never run concurrently
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2010-02-24 02:23:11

#3958: ssl::stream async_read_some and async_write_some handlers never run
concurrently
--------------------------------------------------------+-------------------
 Reporter:  L McGuinness <lorcan.mcguinness@…>          |       Owner:  chris_kohlhoff
     Type:  Bugs                                        |      Status:  new           
Milestone:  To Be Determined                            |   Component:  asio          
  Version:  Boost 1.42.0                                |    Severity:  Problem       
 Keywords:  openssl ssl strand concurrency asio         |  
--------------------------------------------------------+-------------------
 Handlers passed to ssl::stream::async_read_some and
 ssl::stream::async_write_some are always invoked in the context of a
 strand.  This strand is a member of openssl_stream_service, which is
 typically a process-wide instance.

 The effect of this is that a time-consuming async_read_some handler on one
 ssl::stream instance can block all other async_read_some and
 async_write_some handlers on other instances of ssl::stream.

 The code that does this is in boost/asio/ssl/detail/openssl_operation.hpp.
 Line 319 performs strand::wrap on the callback to
 openssl_operation::async_write_handler.  At lines 367 and 373,
 async_write_handler invokes the user's handler function (passed to
 ssl::stream::async_write_some).  This runs in the context of strand_.

 The strand instance in this case is always
 openssl_stream_service::strand_, as can be seen in
 asio/ssl/detail/openssl_stream_service.hpp, line 395.

 The situation for async_read_handler is similar.

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/3958>
Boost C++ Libraries <http://www.boost.org/>
Boost provides free peer-reviewed portable C++ source libraries.