[LTP] [PATCH] syscalls/execveat03: Fix compiler errors

[Xiao Yang]

According to open(2) and linkat(2) manpages, O_PATH and AT_EMPTY_PATH
flags were added since kernel v2.6.39, so these undefined flags led
to the following errors on older kernels(e.g. v2.6.32):
---------------------------------------------------------
execveat03.c:66: error: ‘O_PATH’ undeclared (first use in this function)
execveat03.c:69: error: ‘AT_EMPTY_PATH’ undeclared (first use in this function)
---------------------------------------------------------

1) Add AT_EMPTY_PATH into lapi/fcntl.h
2) Include lapi/fcntl.h in execveat03.c
3) Check if open(2) supports O_PATH

Signed-off-by: Xiao Yang <yangx.jy@cn.fujitsu.com>
---
 include/lapi/fcntl.h                            |  4 ++++
 testcases/kernel/syscalls/execveat/execveat03.c | 10 +++++++++-
 2 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/include/lapi/fcntl.h b/include/lapi/fcntl.h
index 849439d..358230f 100644
--- a/include/lapi/fcntl.h
+++ b/include/lapi/fcntl.h
@@ -103,6 +103,10 @@
 # define AT_SYMLINK_NOFOLLOW 0x100
 #endif
 
+#ifndef AT_EMPTY_PATH
+# define AT_EMPTY_PATH 0x1000
+#endif
+
 #ifndef AT_REMOVEDIR
 # define AT_REMOVEDIR 0x200
 #endif
diff --git a/testcases/kernel/syscalls/execveat/execveat03.c b/testcases/kernel/syscalls/execveat/execveat03.c
index df27273..701784e 100644
--- a/testcases/kernel/syscalls/execveat/execveat03.c
+++ b/testcases/kernel/syscalls/execveat/execveat03.c
@@ -49,6 +49,7 @@
 #include <fcntl.h>
 #include "tst_test.h"
 #include "lapi/execveat.h"
+#include "lapi/fcntl.h"
 
 #define OVL_MNT "ovl"
 #define TEST_APP "execveat_child"
@@ -63,7 +64,14 @@ static void do_child(void)
 
 	SAFE_CP(TEST_APP, TEST_FILE_PATH);
 
-	fd = SAFE_OPEN(TEST_FILE_PATH, O_PATH);
+	fd = open(TEST_FILE_PATH, O_PATH);
+	if (fd == -1) {
+		if (errno == EINVAL)
+			tst_brk(TCONF, "open() did not support O_PATH");
+		else
+			tst_brk(TBROK, "open() failed");
+	}
+
 	SAFE_UNLINK(TEST_FILE_PATH);
 
 	TEST(execveat(fd, "", argv, environ, AT_EMPTY_PATH));
-- 
1.8.3.1