fixes #1169 survey and xsurvey could use message cloning

fixes #1160 Consider limiting maximum hop count to 15
fixes #1098 Maximum maxTTL should be compile time defined

This doesn't expose the max-MaxTTL in the CMakeList.txt -- there
is really no reason anyone should be changing it.  This does not
yet inline the message header into the nni_msg_t, but it is my
intention to do so soon, and eliminate most of the conditional cases
for failure on inserting into the header.

1 files changed, 2 insertions, 4 deletions

diff --git a/src/protocol/survey0/xrespond.c b/src/protocol/survey0/xrespond.c
index 73e541d3..c664f009 100644
--- a/src/protocol/survey0/xrespond.c
+++ b/src/protocol/survey0/xrespond.c
@@ -284,9 +284,7 @@ xresp0_recv_cb(void *arg)
 	nni_msg_set_pipe(msg, p->id);
 
 	// Store the pipe id in the header, first thing.
-	if (nni_msg_header_append_u32(msg, p->id) != 0) {
-		goto drop;
-	}
+	nni_msg_header_must_append_u32(msg, p->id);
 
 	// Move backtrace from body to header
 	hops = 1;
@@ -346,7 +344,7 @@ xresp0_sock_set_maxttl(void *arg, const void *buf, size_t sz, nni_opt_type t)
 	xresp0_sock *s = arg;
 	int ttl;
 	int rv;
-	if ((rv = nni_copyin_int(&ttl, buf, sz, 1, 255, t)) == 0) {
+	if ((rv = nni_copyin_int(&ttl, buf, sz, 1, NNI_MAX_MAX_TTL, t)) == 0) {
 		nni_atomic_set(&s->ttl, ttl);
 	}
 	return (rv);