irmd: Allow direct rbuff between local processes

This allows bypassing the IPCP for local processes that share the same
packet pool, lowering latency between processes to comparable levels
as Unix sockets (RTT in the order of a microsecond).

For local processes, no IPCPs are needed:

 $ irm b prog oping n oping
 $ oping -l
 Ouroboros ping server started.
 New flow 64.
 Received 64 bytes on fd 64.

The direct IPC can be disabled with the DISABLE_DIRECT_IPC build
flag. Note that this is needed for rumba 'local' experiments to
emulate network topologies. Without this flag all processes will just
communicate directly.

Signed-off-by: Dimitri Staessens <dimitri@ouroboros.rocks>
Signed-off-by: Sander Vrijders <sander@ouroboros.rocks>

1 files changed, 13 insertions, 0 deletions

diff --git a/src/irmd/reg/reg.h b/src/irmd/reg/reg.h
index bda57711..6b576471 100644
--- a/src/irmd/reg/reg.h
+++ b/src/irmd/reg/reg.h
@@ -150,6 +150,19 @@ int   reg_wait_flow_accepting(const char *            name,
 int   reg_respond_accept(struct flow_info * info,
                          buffer_t *         pbuf);
 
+int   reg_prepare_flow_direct(struct flow_info * info,
+                              buffer_t *         pbuf,
+                              uid_t              alloc_uid);
+
+int   reg_respond_flow_direct(int              flow_id,
+                              buffer_t *       pbuf);
+
+int   reg_wait_flow_direct(int                      flow_id,
+                           buffer_t *               pbuf,
+                           const struct timespec *  abstime);
+
+bool  reg_flow_is_direct(int flow_id);
+
 void  reg_dealloc_flow(struct flow_info * info);
 
 void  reg_dealloc_flow_resp(struct flow_info * info);