*: always set SO_SNDBUF and SO_RCVBUF using a best effort approach

If we fail to set any socket's buffer size, try again with a smaller value
and keep going until it succeeds. This is better than just giving up or,
even worse, abort the creation of a socket (ospf6d and ripd).

Fix broken ospf6d on FreeBSD.

Signed-off-by: Renato Westphal <renato@opensourcerouting.org>
Signed-off-by: David Lamparter <equinox@opensourcerouting.org>

2 files changed, 18 insertions, 18 deletions

diff --git a/lib/sockopt.c b/lib/sockopt.c
index be3ac0e4b..461e1f7f5 100644
--- a/lib/sockopt.c
+++ b/lib/sockopt.c
@@ -29,30 +29,30 @@
 #include "sockopt.h"
 #include "sockunion.h"
 
-int
+void
 setsockopt_so_recvbuf (int sock, int size)
 {
-  int ret;
-  
-  if ( (ret = setsockopt (sock, SOL_SOCKET, SO_RCVBUF, (char *)
-                          &size, sizeof (int))) < 0)
-    zlog_err ("fd %d: can't setsockopt SO_RCVBUF to %d: %s",
-	      sock,size,safe_strerror(errno));
+  int orig_req = size;
 
-  return ret;
+  while (setsockopt(sock, SOL_SOCKET, SO_RCVBUF, &size, sizeof (size)) == -1)
+    size /= 2;
+
+  if (size != orig_req)
+    zlog_warn ("%s: fd %d: SO_RCVBUF set to %d (requested %d)", __func__, sock,
+	       size, orig_req);
 }
 
-int
+void
 setsockopt_so_sendbuf (const int sock, int size)
 {
-  int ret = setsockopt (sock, SOL_SOCKET, SO_SNDBUF,
-    (char *)&size, sizeof (int));
-  
-  if (ret < 0)
-    zlog_err ("fd %d: can't setsockopt SO_SNDBUF to %d: %s",
-      sock, size, safe_strerror (errno));
+  int orig_req = size;
 
-  return ret;
+  while (setsockopt(sock, SOL_SOCKET, SO_SNDBUF, &size, sizeof (size)) == -1)
+    size /= 2;
+
+  if (size != orig_req)
+    zlog_warn ("%s: fd %d: SO_SNDBUF set to %d (requested %d)", __func__, sock,
+	       size, orig_req);
 }
 
 int
diff --git a/lib/sockopt.h b/lib/sockopt.h
index 02f018934..b3ab57ab7 100644
--- a/lib/sockopt.h
+++ b/lib/sockopt.h
@@ -24,8 +24,8 @@
 
 #include "sockunion.h"
 
-extern int setsockopt_so_recvbuf (int sock, int size);
-extern int setsockopt_so_sendbuf (const int sock, int size);
+extern void setsockopt_so_recvbuf (int sock, int size);
+extern void setsockopt_so_sendbuf (const int sock, int size);
 extern int getsockopt_so_sendbuf (const int sock);
 
 #ifdef HAVE_IPV6