timestamping: fix example build

Fix Makefiles so that Documentation/networking/timestamping/timestamping.c
will build when using the CONFIG_BUILD_DOCSRC kconfig option.
(timestamping.c does not build currently with its simple Makefile.)

Also fix printf format warnings.

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Patrick Ohly <patrick.ohly@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 14 insertions, 7 deletions

diff --git a/Documentation/networking/timestamping/Makefile b/Documentation/networking/timestamping/Makefile
index 2a1489fdc036..e79973443e9f 100644
--- a/Documentation/networking/timestamping/Makefile
+++ b/Documentation/networking/timestamping/Makefile
@@ -1,6 +1,13 @@
-CPPFLAGS = -I../../../include
+# kbuild trick to avoid linker error. Can be omitted if a module is built.
+obj- := dummy.o
 
-timestamping: timestamping.c
+# List of programs to build
+hostprogs-y := timestamping
+
+# Tell kbuild to always build the programs
+always := $(hostprogs-y)
+
+HOSTCFLAGS_timestamping.o += -I$(objtree)/usr/include
 
 clean:
         rm -f timestamping
diff --git a/Documentation/networking/timestamping/timestamping.c b/Documentation/networking/timestamping/timestamping.c
index a7936fe8444a..7b81d169cb0f 100644
--- a/Documentation/networking/timestamping/timestamping.c
+++ b/Documentation/networking/timestamping/timestamping.c
@@ -41,9 +41,9 @@
 #include <arpa/inet.h>
 #include <net/if.h>
 
-#include "asm/types.h"
-#include "linux/net_tstamp.h"
-#include "linux/errqueue.h"
+#include <asm/types.h>
+#include <linux/net_tstamp.h>
+#include <linux/errqueue.h>
 
 #ifndef SO_TIMESTAMPING
 # define SO_TIMESTAMPING         37
@@ -164,7 +164,7 @@ static void printpacket(struct msghdr *msg, int res,
 
         gettimeofday(&now, 0);
 
-        printf("%ld.%06ld: received %s data, %d bytes from %s, %d bytes control messages\n",
+        printf("%ld.%06ld: received %s data, %d bytes from %s, %zu bytes control messages\n",
                (long)now.tv_sec, (long)now.tv_usec,
                (recvmsg_flags & MSG_ERRQUEUE) ? "error" : "regular",
                res,
@@ -173,7 +173,7 @@ static void printpacket(struct msghdr *msg, int res,
         for (cmsg = CMSG_FIRSTHDR(msg);
              cmsg;
              cmsg = CMSG_NXTHDR(msg, cmsg)) {
-                printf("   cmsg len %d: ", cmsg->cmsg_len);
+                printf("   cmsg len %zu: ", cmsg->cmsg_len);
                 switch (cmsg->cmsg_level) {
                 case SOL_SOCKET:
                         printf("SOL_SOCKET ");