[PATCH 1/6] selftests: Add printf attribute to ksefltest prints

["Wieczor-Retman, Maciej" <maciej.wieczor-retman@xxxxxxxxx>]

Kselftest header defines multiple variadic function that use printf
along with other logic.

There is no format checking for the variadic functions that use
printing inside kselftest.h. Because of this the compiler won't
be able to catch instances of mismatched print formats and debugging
tests might be more difficult.

Add the common __printf attribute macro to kselftest.h.

Add __printf attribute to every function using formatted printing with
variadic arguments.

Signed-off-by: Wieczor-Retman, Maciej <maciej.wieczor-retman@xxxxxxxxx>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@xxxxxxxxxxxxxxx>
---
 tools/testing/selftests/kselftest.h | 18 ++++++++++--------
 1 file changed, 10 insertions(+), 8 deletions(-)

diff --git a/tools/testing/selftests/kselftest.h b/tools/testing/selftests/kselftest.h
index 829be379545a..ff47ed711879 100644
--- a/tools/testing/selftests/kselftest.h
+++ b/tools/testing/selftests/kselftest.h
@@ -77,6 +77,8 @@
 #define KSFT_XPASS 3
 #define KSFT_SKIP  4
 
+#define __printf(a, b)   __attribute__((format(printf, a, b)))
+
 /* counters */
 struct ksft_count {
 	unsigned int ksft_pass;
@@ -134,7 +136,7 @@ static inline void ksft_print_cnts(void)
 		ksft_cnt.ksft_xskip, ksft_cnt.ksft_error);
 }
 
-static inline void ksft_print_msg(const char *msg, ...)
+static inline __printf(1, 2) void ksft_print_msg(const char *msg, ...)
 {
 	int saved_errno = errno;
 	va_list args;
@@ -146,7 +148,7 @@ static inline void ksft_print_msg(const char *msg, ...)
 	va_end(args);
 }
 
-static inline void ksft_test_result_pass(const char *msg, ...)
+static inline __printf(1, 2) void ksft_test_result_pass(const char *msg, ...)
 {
 	int saved_errno = errno;
 	va_list args;
@@ -160,7 +162,7 @@ static inline void ksft_test_result_pass(const char *msg, ...)
 	va_end(args);
 }
 
-static inline void ksft_test_result_fail(const char *msg, ...)
+static inline __printf(1, 2) void ksft_test_result_fail(const char *msg, ...)
 {
 	int saved_errno = errno;
 	va_list args;
@@ -186,7 +188,7 @@ static inline void ksft_test_result_fail(const char *msg, ...)
 		ksft_test_result_fail(fmt, ##__VA_ARGS__);\
 	} while (0)
 
-static inline void ksft_test_result_xfail(const char *msg, ...)
+static inline __printf(1, 2) void ksft_test_result_xfail(const char *msg, ...)
 {
 	int saved_errno = errno;
 	va_list args;
@@ -200,7 +202,7 @@ static inline void ksft_test_result_xfail(const char *msg, ...)
 	va_end(args);
 }
 
-static inline void ksft_test_result_skip(const char *msg, ...)
+static inline __printf(1, 2) void ksft_test_result_skip(const char *msg, ...)
 {
 	int saved_errno = errno;
 	va_list args;
@@ -215,7 +217,7 @@ static inline void ksft_test_result_skip(const char *msg, ...)
 }
 
 /* TODO: how does "error" differ from "fail" or "skip"? */
-static inline void ksft_test_result_error(const char *msg, ...)
+static inline __printf(1, 2) void ksft_test_result_error(const char *msg, ...)
 {
 	int saved_errno = errno;
 	va_list args;
@@ -262,7 +264,7 @@ static inline int ksft_exit_fail(void)
 		  ksft_cnt.ksft_xfail +	\
 		  ksft_cnt.ksft_xskip)
 
-static inline int ksft_exit_fail_msg(const char *msg, ...)
+static inline __printf(1, 2) int ksft_exit_fail_msg(const char *msg, ...)
 {
 	int saved_errno = errno;
 	va_list args;
@@ -289,7 +291,7 @@ static inline int ksft_exit_xpass(void)
 	exit(KSFT_XPASS);
 }
 
-static inline int ksft_exit_skip(const char *msg, ...)
+static inline __printf(1, 2) int ksft_exit_skip(const char *msg, ...)
 {
 	int saved_errno = errno;
 	va_list args;
-- 
2.42.0