[LTP] [PATCH v2 3/3] fanotify: Detect val vs. __val fanotify_event_info_fid.fsid member

[Petr Vorel]

via FSID_VAL_MEMBER() macro and autotools detection.

This fixes build on musl, which also defines fanotify_event_info_fid,
but uses fsid_t type for fsid instead of __kernel_fsid_t.
fsid_t type has __val[2] member (unlike val[2] in __kernel_fsid_t).

Fixed error:

fanotify13.c: In function ‘do_test’:
fanotify13.c:278:20: error: ‘fsid_t’ {aka ‘struct __fsid_t’} has no member named ‘val’; did you mean ‘__val’?
    event_fid->fsid.val[0],
		    ^~~
../../../../include/tst_test.h:49:53: note: in definition of macro ‘tst_res’
  tst_res_(__FILE__, __LINE__, (ttype), (arg_fmt), ##__VA_ARGS__)
						     ^~~~~~~~~~~
fanotify13.c:279:20: error: ‘fsid_t’ {aka ‘struct __fsid_t’} has no member named ‘val’; did you mean ‘__val’?
    event_fid->fsid.val[1],

Signed-off-by: Petr Vorel <petr.vorel@gmail.com>
---
Changes v1->v2:
* access members via macro FSID_VAL_MEMBER()
* use autotools detection 

 m4/ltp-fanotify.m4                              | 1 +
 testcases/kernel/syscalls/fanotify/fanotify.h   | 6 ++++++
 testcases/kernel/syscalls/fanotify/fanotify13.c | 8 ++++----
 testcases/kernel/syscalls/fanotify/fanotify15.c | 4 ++--
 4 files changed, 13 insertions(+), 6 deletions(-)

diff --git a/m4/ltp-fanotify.m4 b/m4/ltp-fanotify.m4
index e7b77d8a4..f2e31eb68 100644
--- a/m4/ltp-fanotify.m4
+++ b/m4/ltp-fanotify.m4
@@ -4,4 +4,5 @@ dnl Copyright (c) 2019 Petr Vorel <petr.vorel@gmail.com>
 AC_DEFUN([LTP_CHECK_FANOTIFY],[
 AC_CHECK_TYPES([struct fanotify_event_info_header],,,[#include <sys/fanotify.h>])
 AC_CHECK_TYPES([struct fanotify_event_info_fid],,,[#include <sys/fanotify.h>])
+AC_CHECK_MEMBERS([struct fanotify_event_info_fid.fsid.__val],,,[#include <sys/fanotify.h>])
 ])
diff --git a/testcases/kernel/syscalls/fanotify/fanotify.h b/testcases/kernel/syscalls/fanotify/fanotify.h
index 9d2fded13..5370e30bb 100644
--- a/testcases/kernel/syscalls/fanotify/fanotify.h
+++ b/testcases/kernel/syscalls/fanotify/fanotify.h
@@ -143,6 +143,12 @@ struct fanotify_event_info_fid {
 };
 #endif /* HAVE_STRUCT_FANOTIFY_EVENT_INFO_FID */
 
+#ifdef HAVE_STRUCT_FANOTIFY_EVENT_INFO_FID_FSID___VAL
+# define FSID_VAL_MEMBER(fsid, i) (fsid.__val[i])
+#else
+# define FSID_VAL_MEMBER(fsid, i) (fsid.val[i])
+#endif /* HAVE_STRUCT_FANOTIFY_EVENT_INFO_FID_FSID___VAL */
+
 #ifdef HAVE_NAME_TO_HANDLE_AT
 /*
  * Helper function used to obtain fsid and file_handle for a given path.
diff --git a/testcases/kernel/syscalls/fanotify/fanotify13.c b/testcases/kernel/syscalls/fanotify/fanotify13.c
index 030734285..b0d9fb5b6 100644
--- a/testcases/kernel/syscalls/fanotify/fanotify13.c
+++ b/testcases/kernel/syscalls/fanotify/fanotify13.c
@@ -130,8 +130,8 @@ static int setup_marks(unsigned int fd, struct test_case_t *tc)
 					"kernel");
 				return 1;
 			} else if (errno == ENODEV &&
-					!event_set[i].fsid.val[0] &&
-					!event_set[i].fsid.val[1]) {
+					!FSID_VAL_MEMBER(event_set[i].fsid, 0) &&
+					!FSID_VAL_MEMBER(event_set[i].fsid, 1)) {
 				tst_res(TCONF,
 					"FAN_REPORT_FID not supported on "
 					"filesystem type %s",
@@ -275,8 +275,8 @@ static void do_test(unsigned int number)
 			"and name_to_handle_at(2)",
 			metadata->mask,
 			getpid(),
-			event_fid->fsid.val[0],
-			event_fid->fsid.val[1],
+			FSID_VAL_MEMBER(event_fid->fsid, 0),
+			FSID_VAL_MEMBER(event_fid->fsid, 1),
 			*(unsigned long *) event_file_handle->f_handle);
 	}
 out:
diff --git a/testcases/kernel/syscalls/fanotify/fanotify15.c b/testcases/kernel/syscalls/fanotify/fanotify15.c
index e9e926078..48ed368ae 100644
--- a/testcases/kernel/syscalls/fanotify/fanotify15.c
+++ b/testcases/kernel/syscalls/fanotify/fanotify15.c
@@ -192,8 +192,8 @@ static void do_test(void)
 				"fid=%x.%x.%lx values",
 				metadata->mask,
 				getpid(),
-				event_fid->fsid.val[0],
-				event_fid->fsid.val[1],
+				FSID_VAL_MEMBER(event_fid->fsid, 0),
+				FSID_VAL_MEMBER(event_fid->fsid, 1),
 				*(unsigned long *)
 				event_file_handle->f_handle);
 		}
-- 
2.24.0