From: Miroslav Lichvar <mlichvar@redhat.com>
Date: Tue, 8 Dec 2015 09:20:20 +0000 (+0100)
Subject: privops: use SOCK_SEQPACKET sockets when supported
X-Git-Tag: 2.3-pre1~72
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=aa4bf4140023dc009753a7b1ea41e85dbb18dd16;p=thirdparty%2Fchrony.git

privops: use SOCK_SEQPACKET sockets when supported

SOCK_SEQPACKET is preferred over SOCK_DGRAM for communication with the
helper as the process will get an error when the other end of the socket
is closed. It's not supported on all platforms.

If SOCK_SEQPACKET is defined, try creating the pair of sockets with this
type first and if that fails, fall back to SOCK_DGRAM.
---

diff --git a/privops.c b/privops.c
index d53583c8..82b56602 100644
--- a/privops.c
+++ b/privops.c
@@ -450,7 +450,11 @@ PRV_Initialise(void)
   if (have_helper())
     LOG_FATAL(LOGF_PrivOps, "Helper already running");
 
-  if (socketpair(AF_UNIX, SOCK_DGRAM, 0, sock_pair))
+  if (
+#ifdef SOCK_SEQPACKET
+      socketpair(AF_UNIX, SOCK_SEQPACKET, 0, sock_pair) &&
+#endif
+      socketpair(AF_UNIX, SOCK_DGRAM, 0, sock_pair))
     LOG_FATAL(LOGF_PrivOps, "socketpair() failed : %s", strerror(errno));
 
   UTI_FdSetCloexec(sock_pair[0]);