Implement SP wire protocol

Implements the SP wire protocol, and infrastructure for legacy wire
protocol support.

Also added an XS_SERVICE_ID socket option to set the service id and renamed
the XS_PROTOCOL option to XS_PATTERN_VERSION.

The following pattern versions are supported:

PAIR:     v3
PUBSUB:   v1 (legacy), v4
REQREP:   v2
PIPELINE: v3
SURVEY:   v2

Note that all existing pattern versions have been bumped by 1 to allow for
use of legacy protocols (otherwise there would be no way to distinguish
between e.g. PUBSUB v3 and PUBSUB v3 using SP).

Signed-off-by: Martin Lucina <martin@lucina.net>

1 files changed, 8 insertions, 8 deletions

diff --git a/src/pipe.hpp b/src/pipe.hpp
index c298154..dbc6b7e 100644
--- a/src/pipe.hpp
+++ b/src/pipe.hpp
@@ -44,7 +44,7 @@ namespace xs
     //  pipe receives all the pending messages before terminating, otherwise it
     //  terminates straight away.
     int pipepair (xs::object_t *parents_ [2], xs::pipe_t* pipes_ [2],
-        int hwms_ [2], bool delays_ [2], int protocol_);
+        int hwms_ [2], bool delays_ [2], int sp_version_);
 
     struct i_pipe_events
     {
@@ -69,7 +69,7 @@ namespace xs
         //  This allows pipepair to create pipe objects.
         friend int pipepair (xs::object_t *parents_ [2],
             xs::pipe_t* pipes_ [2], int hwms_ [2], bool delays_ [2],
-            int protocol_);
+            int sp_version_);
 
     public:
 
@@ -111,8 +111,8 @@ namespace xs
         //  before actual shutdown.
         void terminate (bool delay_);
 
-        //  Returns the ID of the protocol associated with the pipe.
-        int get_protocol ();
+        //  Returns the SP pattern version in use on this pipe.
+        int get_sp_version ();
 
     private:
 
@@ -132,7 +132,7 @@ namespace xs
         //  Constructor is private. Pipe can only be created using
         //  pipepair function.
         pipe_t (object_t *parent_, upipe_t *inpipe_, upipe_t *outpipe_,
-            int inhwm_, int outhwm_, bool delay_, int protocol_);
+            int inhwm_, int outhwm_, bool delay_, int sp_version_);
 
         //  Pipepair uses this function to let us know about
         //  the peer pipe object.
@@ -192,9 +192,9 @@ namespace xs
         //  asks us to.
         bool delay;
 
-        //  ID of the protocol to use. This value is not used by the pipe
-        //  itself, rather it's used by the users of the pipe.
-        int protocol;
+        //  SP pattern version in use on this pipe. This value is used by the
+        //  pattern classes using the pipe, not the pipe itself.
+        int sp_version;
 
         //  Identity of the writer. Used uniquely by the reader side.
         blob_t identity;