Pipe IDs are now tracked by hash table for performance.

This gives a better idea of pipe ID uniqueness, and is a step towards
conversion of the API to use IDs instead of pointers.

3 files changed, 26 insertions, 16 deletions

diff --git a/src/core/pipe.c b/src/core/pipe.c
index 0633dea9..6cc93d98 100644
--- a/src/core/pipe.c
+++ b/src/core/pipe.c
@@ -121,6 +121,7 @@ nni_pipe_create(nni_pipe **pp, nni_ep *ep)
 	p->p_tran_data = NULL;
 	p->p_proto_data = NULL;
 	p->p_active = 0;
+	p->p_id = 0;
 	NNI_LIST_NODE_INIT(&p->p_node);
 
 	// Make a copy of the transport ops.  We can override entry points
@@ -168,7 +169,6 @@ nni_pipe_start(nni_pipe *pipe)
 {
 	int rv;
 	int i;
-	int collide;
 	nni_sock *sock = pipe->p_sock;
 
 	nni_mtx_lock(&sock->s_mx);
@@ -184,23 +184,16 @@ nni_pipe_start(nni_pipe *pipe)
 		return (NNG_EPROTO);
 	}
 
-	do {
-		// We generate a new pipe ID, but we make sure it does not
-		// collide with any we already have.  This can only normally
-		// happen if we wrap -- i.e. we've had 4 billion or so pipes.
-		// XXX: consider making this a hash table!!
-		nni_pipe *check;
-		pipe->p_id = nni_random() & 0x7FFFFFFF;
-		collide = 0;
-		NNI_LIST_FOREACH (&sock->s_pipes, check) {
-			if ((pipe != check) && (check->p_id == pipe->p_id)) {
-				collide = 1;
-				break;
-			}
-		}
-	} while (collide);
+	rv = nni_idhash_alloc(sock->s_pipes_by_id, &pipe->p_id, pipe);
+	if (rv != 0) {
+		nni_pipe_bail(pipe);
+		nni_mtx_unlock(&sock->s_mx);
+		return (rv);
+	}
 
 	if ((rv = sock->s_pipe_ops.pipe_add(pipe->p_proto_data)) != 0) {
+		nni_idhash_remove(sock->s_pipes_by_id, pipe->p_id);
+		pipe->p_id = 0;
 		nni_pipe_bail(pipe);
 		nni_mtx_unlock(&sock->s_mx);
 		return (rv);
diff --git a/src/core/socket.c b/src/core/socket.c
index 1e9fe11f..e19485a5 100644
--- a/src/core/socket.c
+++ b/src/core/socket.c
@@ -47,6 +47,10 @@ nni_reaper(void *arg)
 		nni_mtx_lock(&sock->s_mx);
 		if ((pipe = nni_list_first(&sock->s_reaps)) != NULL) {
 			nni_list_remove(&sock->s_reaps, pipe);
+			if (pipe->p_id != 0) {
+				nni_idhash_remove(sock->s_pipes_by_id,
+				    pipe->p_id);
+			}
 
 			if (((ep = pipe->p_ep) != NULL) &&
 			    ((ep->ep_pipe == pipe))) {
@@ -232,6 +236,15 @@ nni_sock_open(nni_sock **sockp, uint16_t pnum)
 		goto fail;
 	}
 
+	if ((rv = nni_idhash_create(&sock->s_pipes_by_id)) != 0) {
+		goto fail;
+	}
+	// Pipe IDs are always positive values with the upper bit clear.
+	// Start the IDs at a random place to minimize chances of PIPE ID
+	// reuse improperly.
+	nni_idhash_set_limits(sock->s_pipes_by_id, 1, 0x7FFFFFFF,
+	    nni_random() & 0x7FFFFFFF);
+
 	rv = nni_ev_init(&sock->s_recv_ev, NNG_EV_CAN_RECV, sock);
 	if (rv != 0) {
 		goto fail;
@@ -290,6 +303,7 @@ fail:
 	nni_ev_fini(&sock->s_recv_ev);
 	nni_msgq_fini(sock->s_urq);
 	nni_msgq_fini(sock->s_uwq);
+	nni_idhash_destroy(sock->s_pipes_by_id);
 	nni_cv_fini(&sock->s_notify_cv);
 	nni_cv_fini(&sock->s_cv);
 	nni_mtx_fini(&sock->s_notify_mx);
@@ -428,6 +442,7 @@ nni_sock_close(nni_sock *sock)
 	nni_msgq_fini(sock->s_uwq);
 	nni_ev_fini(&sock->s_send_ev);
 	nni_ev_fini(&sock->s_recv_ev);
+	nni_idhash_destroy(sock->s_pipes_by_id);
 	nni_cv_fini(&sock->s_notify_cv);
 	nni_cv_fini(&sock->s_cv);
 	nni_mtx_fini(&sock->s_notify_mx);
diff --git a/src/core/socket.h b/src/core/socket.h
index 424b1321..2860ad46 100644
--- a/src/core/socket.h
+++ b/src/core/socket.h
@@ -42,6 +42,8 @@ struct nng_socket {
 	nni_cv			s_notify_cv;    // wakes notify thread
 	nni_mtx			s_notify_mx;    // protects s_notify list
 
+	nni_idhash *		s_pipes_by_id;  // pipes by id
+
 	nni_list		s_reaps;        // pipes to reap
 	nni_thr			s_reaper;
 	nni_thr			s_notifier;