[LTP] [PATCH] syscalls/time01:Avoid using TST_RET in time() test to support Y2038-safe time_t

[jiaying.song.cn@windriver.com]

From: Jiaying Song <jiaying.song.cn@windriver.com>

On 32-bit systems with Y2038 support, time_t is 64-bit while TST_RET remains a long (usually 32-bit). 
Using TST_RET to store the return value of time() causes overflow after 2038, leading to incorrect comparisons 
and false test failures like:

    TFAIL: time() returned value -2085977741, stored value 2208989555 are different

This patch replaces usage of TST_RET with a local variable of type time_t (ret_time), 
ensuring correct behavior with large timestamps and avoiding truncation.

Signed-off-by: Jiaying Song <jiaying.song.cn@windriver.com>
---
 testcases/kernel/syscalls/time/time01.c | 19 ++++++++++---------
 1 file changed, 10 insertions(+), 9 deletions(-)

diff --git a/testcases/kernel/syscalls/time/time01.c b/testcases/kernel/syscalls/time/time01.c
index d8625c0..3da7f1c 100644
--- a/testcases/kernel/syscalls/time/time01.c
+++ b/testcases/kernel/syscalls/time/time01.c
@@ -24,24 +24,25 @@ time_t *targs[] = {
 static void verify_time(unsigned int i)
 {
 	time_t *tloc = targs[i];
+        time_t ret_time = time(tloc);        
+        
+        ret_time = time(tloc);
 
-	TEST(time(tloc));
-
-	if (TST_RET == -1) {
+	if (ret_time == -1) {
 		tst_res(TFAIL | TTERRNO, "time()");
 		return;
 	}
 
 	if (!tloc)
-		tst_res(TPASS, "time() returned value %ld", TST_RET);
-	else if (*tloc == TST_RET)
+		tst_res(TPASS, "time() returned value %lld", ret_time);
+	else if (*tloc == ret_time)
 		tst_res(TPASS,
-			"time() returned value %ld, stored value %jd are same",
-			TST_RET, (intmax_t) *tloc);
+			"time() returned value %lld, stored value %jd are same",
+			ret_time, (intmax_t) *tloc);
 	else
 		tst_res(TFAIL,
-			"time() returned value %ld, stored value %jd are different",
-			TST_RET, (intmax_t) *tloc);
+			"time() returned value %lld, stored value %jd are different",
+			ret_time, (intmax_t) *tloc);
 }
 
 static struct tst_test test = {
-- 
2.34.1