[PATCH 1/2] selftests: add ksft_exit_fail_perror()

[Muhammad Usama Anjum <usama.anjum@collabora.com>]

Add a version of ksft_exit_fail_msg() which prints the errno and its
string form with ease. There is no benefit of exit message without
errno. Whenever some error occurs, instead of printing errno manually,
this function would be very helpful. In the next TAP ports or new tests,
this function will be used instead of ksft_exit_fail_msg() as it prints
errno.

Signed-off-by: Muhammad Usama Anjum <usama.anjum@collabora.com>
---
 tools/testing/selftests/kselftest.h | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/tools/testing/selftests/kselftest.h b/tools/testing/selftests/kselftest.h
index 159bf8e314fa3..2cd93d220f434 100644
--- a/tools/testing/selftests/kselftest.h
+++ b/tools/testing/selftests/kselftest.h
@@ -41,6 +41,7 @@
  * the program is aborting before finishing all tests):
  *
  *    ksft_exit_fail_msg(fmt, ...);
+ *    ksft_exit_fail_perror(msg);
  *
  */
 #ifndef __KSELFTEST_H
@@ -370,6 +371,19 @@ static inline __printf(1, 2) int ksft_exit_fail_msg(const char *msg, ...)
 	exit(KSFT_FAIL);
 }
 
+static inline void ksft_exit_fail_perror(const char *msg)
+{
+#ifndef NOLIBC
+	ksft_exit_fail_msg("%s: %s (%d)\n", msg, strerror(errno), errno);
+#else
+	/*
+	 * nolibc doesn't provide strerror() and it seems
+	 * inappropriate to add one, just print the errno.
+	 */
+	ksft_exit_fail_msg("%s: %d)\n", msg, errno);
+#endif
+}
+
 static inline int ksft_exit_xfail(void)
 {
 	ksft_print_cnts();
-- 
2.39.2