[libvirt] [PATCH] configure: Check for MSG_NOSIGNAL availability

[Andrea Bolognani]

The symbol being missing has been reported as causing build
failures on OS X. Check for its availability before using it.
---
See https://www.redhat.com/archives/libvir-list/2016-July/msg00613.html

 configure.ac          | 4 ++++
 src/util/virsystemd.c | 4 ++--
 2 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/configure.ac b/configure.ac
index 2c81c95..af5d2f8 100644
--- a/configure.ac
+++ b/configure.ac
@@ -402,6 +402,10 @@ AC_CHECK_TYPE([struct sockpeercred],
   [], [[#include <sys/socket.h>
   ]])
 
+AC_CHECK_DECLS([MSG_NOSIGNAL],
+  [], [], [[#include <sys/socket.h>
+  ]])
+
 AC_CHECK_DECLS([ETH_FLAG_TXVLAN, ETH_FLAG_NTUPLE, ETH_FLAG_RXHASH, ETH_FLAG_LRO,
                 ETHTOOL_GGSO, ETHTOOL_GGRO, ETHTOOL_GFLAGS, ETHTOOL_GFEATURES],
   [], [], [[#include <linux/ethtool.h>
diff --git a/src/util/virsystemd.c b/src/util/virsystemd.c
index 969cd68..d2f4bfb 100644
--- a/src/util/virsystemd.c
+++ b/src/util/virsystemd.c
@@ -482,7 +482,7 @@ int virSystemdTerminateMachine(const char *name)
 void
 virSystemdNotifyStartup(void)
 {
-#ifdef HAVE_SYS_UN_H
+#if defined(HAVE_SYS_UN_H) && defined(HAVE_MSG_NOSIGNAL)
     const char *path;
     const char *msg = "READY=1";
     int fd;
@@ -526,7 +526,7 @@ virSystemdNotifyStartup(void)
         VIR_WARN("Failed to notify systemd");
 
     VIR_FORCE_CLOSE(fd);
-#endif /* HAVE_SYS_UN_H */
+#endif /* defined(HAVE_SYS_UN_H) && defined(HAVE_MSG_NOSIGNAL) */
 }
 
 static int
-- 
2.7.4