# HG changeset patch
# User Lars Ellenberg <lars@linbit.com>
# Date 1392200751 -3600
# Node ID 37f57a36a2dd1abf8461a9b758e62f6fe7a22f77
# Parent  6d4324633600dc7ae7aa08c56d86c2fcc767977f
Medium: fix usage of SO_REUSEPORT in ucast sockets

Linux learned SO_REUSEPORT only with kernel 3.9,
but some linux headers already define SO_REUSEPORT.
Which, on older kernels, will result in ENOPROTOOPT,
"Protocol not available".

Failure to set SO_REUSEPORT is NOT critical in general.
It *may* be a problem on certain BSDs,
with more than two nodes, all using ucast.

Refusing to start because of failure to set SO_REUSEPORT is
not helpful for the vast majority of the clusters out there.

While at it, downgrade "critical" log messages to warnings
in non-fatal situations.

--- a/lib/plugins/HBcomm/ucast.c
+++ b/lib/plugins/HBcomm/ucast.c
@@ -461,12 +461,6 @@ static int HB_make_send_sock(struct hb_m
 	int sockfd;
 	struct ip_private *ei;
 	int tos;
-#if defined(SO_BINDTODEVICE)
-	struct ifreq i;
-#endif
-#if defined(SO_REUSEPORT)
-	int i = 1;
-#endif
 
 	UCASTASSERT(mp);
 	ei = (struct ip_private*)mp->pd;
@@ -494,6 +488,7 @@ static int HB_make_send_sock(struct hb_m
 
 #if defined(SO_BINDTODEVICE)
 	{
+		struct ifreq i;
 		/*
 		 *  We want to send out this particular interface
 		 *
@@ -515,12 +510,13 @@ static int HB_make_send_sock(struct hb_m
 #endif
 #if defined(SO_REUSEPORT)
 	{
+		int one = 1;
 		/* this is for OpenBSD to allow multiple *
 		*  ucast connections, e.g. a more than   *
 		*  two node cluster 			 */
 
 		if (setsockopt(sockfd, SOL_SOCKET, SO_REUSEPORT,
-				&i, sizeof(i)) == -1) {
+				&one, sizeof(one)) == -1) {
 			PILCallLog(LOG, PIL_CRIT,
 			  "ucast: error setting option SO_REUSEPORT(w): %s", strerror(errno));
 			close(sockfd);
@@ -548,7 +544,7 @@ static int HB_make_receive_sock(struct h
 	int sockfd;
 	int bindtries;
 	int boundyet = 0;
-	int j;
+	int one = 1;
 
 	UCASTASSERT(mp);
 	ei = (struct ip_private*)mp->pd;
@@ -563,22 +559,19 @@ static int HB_make_receive_sock(struct h
 			strerror(errno));
 		return -1;
 	}
-	/* 
- 	 * Set SO_REUSEADDR on the server socket s. Variable j is used
- 	 * as a scratch varable.
- 	 *
- 	 * 16th February 2000
- 	 * Added by Horms <horms@vergenet.net>
- 	 * with thanks to Clinton Work <work@scripty.com>
- 	 */
-	j = 1;
+	/*
+	 * Set SO_REUSEADDR on the server socket s.
+	 * Below, also try to set SO_REUSEPORT,
+	 * if known and supported.
+	 */
 	if (setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR,
-			(void *)&j, sizeof j) < 0) {
+			&one, sizeof(one)) < 0) {
 		/* Ignore it.  It will almost always be OK anyway. */
-		PILCallLog(LOG, PIL_CRIT,
+		PILCallLog(LOG, PIL_WARN,
 			"ucast: error setting socket option SO_REUSEADDR: %s",
 			strerror(errno));
-	}        
+	} else
+		PILCallLog(LOG, PIL_INFO, "ucast: set SO_REUSEADDR");
 #if defined(SO_BINDTODEVICE)
 	{
 		/*
@@ -600,20 +593,32 @@ static int HB_make_receive_sock(struct h
 	}
 #endif
 #if defined(SO_REUSEPORT)
-	{
+	/*
+	 *  Needed for OpenBSD for more than two nodes in a ucast cluster
+	 */
+	if (setsockopt(sockfd, SOL_SOCKET, SO_REUSEPORT,
+			&one, sizeof(one)) == -1) {
 		/*
-		 *  Needed for OpenBSD for more than two nodes in a ucast cluster
+		 * Linux learned SO_REUSEPORT only with kernel 3.9,
+		 * but some linux headers already define SO_REUSEPORT.
+		 * Which will result in ENOPROTOOPT, "Protocol not available"
+		 * on older kernels.
+		 * Failure to set SO_REUSEPORT is NOT critical in general.
+		 * It *may* be a problem on certain BSDs with more than
+		 * two nodes all using ucast.
+		 * Refusing to start because of failure to set SO_REUSEPORT is
+		 * not helpful for the vast majority of the clusters out there.
 		 */
-		int i = 1;
-		if (setsockopt(sockfd, SOL_SOCKET, SO_REUSEPORT,
-				&i, sizeof(i)) == -1) {
+		if (errno == ENOPROTOOPT) {
+			PILCallLog(LOG, PIL_WARN,
+			  "ucast: error setting option SO_REUSEPORT: %s", strerror(errno));
+		} else {
 			PILCallLog(LOG, PIL_CRIT,
-			  "ucast: error setting option SO_REUSEPORT(r) %s", strerror(errno));
-			close(sockfd);
+			  "ucast: error setting option SO_REUSEPORT: %s", strerror(errno));
 			return -1;
 		}
-		PILCallLog(LOG, PIL_INFO, "ucast: set SO_REUSEPORT(w)");
-	}
+	} else
+		PILCallLog(LOG, PIL_INFO, "ucast: set SO_REUSEPORT");
 #endif
 
 	/* Try binding a few times before giving up */