fixes #579 Use ids for pipe listener and dialer

This uses id lookups for pipe listener and dialer during pipe getopt,
while still retaining the pointer fields for use during tear down.
More changes coming.

1 files changed, 32 insertions, 16 deletions

diff --git a/src/core/pipe.c b/src/core/pipe.c
index 02f8ea50..6b9b082c 100644
--- a/src/core/pipe.c
+++ b/src/core/pipe.c
@@ -19,6 +19,9 @@
 
 struct nni_pipe {
 	uint32_t           p_id;
+	uint32_t           p_sock_id;
+	uint32_t           p_dialer_id;
+	uint32_t           p_listener_id;
 	nni_tran_pipe_ops  p_tran_ops;
 	nni_proto_pipe_ops p_proto_ops;
 	void *             p_tran_data;
@@ -312,6 +315,7 @@ nni_pipe_create2(nni_pipe **pp, nni_sock *sock, nni_tran *tran, void *tdata)
 	p->p_proto_ops  = *pops;
 	p->p_proto_data = NULL;
 	p->p_sock       = sock;
+	p->p_sock_id    = nni_sock_id(sock);
 	p->p_closed     = false;
 	p->p_cbs        = false;
 	p->p_refcnt     = 0;
@@ -346,13 +350,15 @@ nni_pipe_create2(nni_pipe **pp, nni_sock *sock, nni_tran *tran, void *tdata)
 void
 nni_pipe_set_listener(nni_pipe *p, nni_listener *l)
 {
-	p->p_listener = l;
+	p->p_listener    = l;
+	p->p_listener_id = nni_listener_id(l);
 }
 
 void
 nni_pipe_set_dialer(nni_pipe *p, nni_dialer *d)
 {
-	p->p_dialer = d;
+	p->p_dialer    = d;
+	p->p_dialer_id = nni_dialer_id(d);
 }
 
 int
@@ -360,6 +366,8 @@ nni_pipe_getopt(
     nni_pipe *p, const char *name, void *val, size_t *szp, nni_opt_type t)
 {
 	nni_tran_option *o;
+	nni_dialer *     d;
+	nni_listener *   l;
 
 	for (o = p->p_tran_ops.p_options; o && o->o_name; o++) {
 		if (strcmp(o->o_name, name) != 0) {
@@ -367,12 +375,25 @@ nni_pipe_getopt(
 		}
 		return (o->o_get(p->p_tran_data, val, szp, t));
 	}
-	// Maybe the endpoint knows?
-	if (p->p_dialer != NULL) {
-		return (nni_dialer_getopt(p->p_dialer, name, val, szp, t));
+
+	// Maybe the endpoint knows?  We look up by ID, instead of using
+	// the links directly, to avoid needing a hold on them.  The pipe
+	// can wind up outliving the endpoint in certain circumstances.
+	// This means that getting these properties from the pipe may wind
+	// up being somewhat more expensive.
+	if ((p->p_dialer_id != 0) &&
+	    (nni_dialer_find(&d, p->p_dialer_id) == 0)) {
+		int rv;
+		rv = nni_dialer_getopt(d, name, val, szp, t);
+		nni_dialer_rele(d);
+		return (rv);
 	}
-	if (p->p_listener != NULL) {
-		return (nni_listener_getopt(p->p_listener, name, val, szp, t));
+	if ((p->p_listener_id != 0) &&
+	    (nni_listener_find(&l, p->p_listener_id) == 0)) {
+		int rv;
+		rv = nni_listener_getopt(l, name, val, szp, t);
+		nni_listener_rele(l);
+		return (rv);
 	}
 	return (NNG_ENOTSUP);
 }
@@ -408,24 +429,19 @@ nni_pipe_ep_list_init(nni_list *list)
 uint32_t
 nni_pipe_sock_id(nni_pipe *p)
 {
-	return (nni_sock_id(p->p_sock));
+	return (p->p_sock_id);
 }
 
 uint32_t
 nni_pipe_listener_id(nni_pipe *p)
 {
-	if (p->p_listener != NULL) {
-		return (nni_listener_id(p->p_listener));
-	}
-	return (0);
+	return (p->p_listener_id);
 }
+
 uint32_t
 nni_pipe_dialer_id(nni_pipe *p)
 {
-	if (p->p_dialer != NULL) {
-		return (nni_dialer_id(p->p_dialer));
-	}
-	return (0);
+	return (p->p_dialer_id);
 }
 
 static void