[LTP] [PATCH v2 1/2] openat2: define _GNU_SOURCE and include <fcntl.h>

[Li Wang]

On Fedora Rawhide (glibc 2.43+), libc exposes openat2() and struct open_how,
so our configure script defines HAVE_OPENAT2 and the fallback definition in
lapi/openat2.h gets skipped. But openat20*.c never included <fcntl.h> (and
lacked _GNU_SOURCE), so the libc-provided prototype and struct stayed hidden,
so compilation failed:

  # uname -r
  6.18.0-65.fc44.x86_64

  # rpm -qf /usr/include/fcntl.h
  glibc-devel-2.43-1.fc44.x86_64

  # nm -D /usr/lib64/libc.so.6 | grep -w openat2
  00000000000eb890 W openat2@@GLIBC_2.43

  # make -C testcase/kernel/syscalls/openat2
  openat201.c:27:62: error: invalid application of ‘sizeof’ to incomplete type ‘struct open_how’
    27 |         {&dir_fd, TEST_FILE, O_RDWR, S_IRWXU, 0, &how, sizeof(*how)},

Define _GNU_SOURCE and include <fcntl.h> in openat2 tests to make the
prototype available and fix the build.

Signed-off-by: Li Wang <liwang@redhat.com>
---
 testcases/kernel/syscalls/openat2/openat201.c | 3 +++
 testcases/kernel/syscalls/openat2/openat202.c | 3 +++
 testcases/kernel/syscalls/openat2/openat203.c | 3 +++
 3 files changed, 9 insertions(+)

diff --git a/testcases/kernel/syscalls/openat2/openat201.c b/testcases/kernel/syscalls/openat2/openat201.c
index ecd63b150..40ac2f6d9 100644
--- a/testcases/kernel/syscalls/openat2/openat201.c
+++ b/testcases/kernel/syscalls/openat2/openat201.c
@@ -4,6 +4,9 @@
  *
  * Basic openat2() test.
  */
+#define _GNU_SOURCE
+#include <fcntl.h>
+
 #include "tst_test.h"
 #include "lapi/openat2.h"
 
diff --git a/testcases/kernel/syscalls/openat2/openat202.c b/testcases/kernel/syscalls/openat2/openat202.c
index 6d1b5a67c..329c6a4a5 100644
--- a/testcases/kernel/syscalls/openat2/openat202.c
+++ b/testcases/kernel/syscalls/openat2/openat202.c
@@ -4,6 +4,9 @@
  *
  * openat2() tests with various resolve flags.
  */
+#define _GNU_SOURCE
+#include <fcntl.h>
+
 #include "tst_test.h"
 #include "lapi/openat2.h"
 
diff --git a/testcases/kernel/syscalls/openat2/openat203.c b/testcases/kernel/syscalls/openat2/openat203.c
index 6ac49ef4c..cd0c00d75 100644
--- a/testcases/kernel/syscalls/openat2/openat203.c
+++ b/testcases/kernel/syscalls/openat2/openat203.c
@@ -4,6 +4,9 @@
  *
  * Basic openat2() test to check various failures.
  */
+#define _GNU_SOURCE
+#include <fcntl.h>
+
 #include "tst_test.h"
 #include "lapi/openat2.h"
 
-- 
2.52.0