QPID-6256: Improved handling of protocol version incompatibilities

* 0-10 path no longer hans on open when connecting to a broker not
  supporting that version
* the 'protocol'  connection option now supports specifying multiple
  protocols to try in order (as a coma separated list)
* the protocol defaults, i.e. the value assumed if the 'protocol'
  connection option is not specified, can now be set via the client
  config file (e.g. protocol-defaults=amqp1.0,amqp0-10) or an
  environment variable (e.g QPID_PROTOCOL_DEFAULTS=amqp1.0,amqp0-10)
* if neither the connection option nor the defaults are specified
  all valid versions will be tried (currently amqp0-10, then amqp1.0
  but this may change in a future version)

git-svn-id: https://svn.apache.org/repos/asf/qpid/trunk@1686078 13f79535-47bb-0310-9956-ffa450edef68

1 files changed, 5 insertions, 0 deletions

diff --git a/qpid/cpp/src/qpid/messaging/ConnectionImpl.h b/qpid/cpp/src/qpid/messaging/ConnectionImpl.h
index 92c6d91b10..05d835b282 100644
--- a/qpid/cpp/src/qpid/messaging/ConnectionImpl.h
+++ b/qpid/cpp/src/qpid/messaging/ConnectionImpl.h
@@ -22,6 +22,7 @@
  *
  */
 #include <string>
+#include <boost/function.hpp>
 #include "qpid/RefCounted.h"
 
 namespace qpid {
@@ -32,6 +33,7 @@ class Variant;
 
 namespace messaging {
 
+class ProtocolRegistry;
 class Session;
 
 class ConnectionImpl : public virtual qpid::RefCounted
@@ -49,7 +51,10 @@ class ConnectionImpl : public virtual qpid::RefCounted
     virtual void reconnect() = 0;
     virtual std::string getUrl() const = 0;
   private:
+  friend class ProtocolRegistry;
+    boost::function<ConnectionImpl*()> next;
 };
+
 }} // namespace qpid::messaging
 
 #endif  /*!QPID_MESSAGING_CONNECTIONIMPL_H*/