selftests: kselftest: add ksft_test_result_code(), handling all exit codes

For generic test harness code it's more useful to deal with exit
codes directly, rather than having to switch on them and call
the right ksft_test_result_*() helper. Add such function to kselftest.h.

Note that "directive" and "diagnostic" are what ktap docs call
those parts of the message.
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

tools/testing/selftests/kselftest.h

@@ -25,6 +25,7 @@
  *     ksft_test_result_skip(fmt, ...);
  *     ksft_test_result_xfail(fmt, ...);
  *     ksft_test_result_error(fmt, ...);
+ *     ksft_test_result_code(exit_code, test_name, fmt, ...);
  *
  * When all tests are finished, clean up and exit the program with one of:
  *
@@ -254,6 +255,44 @@ static inline __printf(1, 2) void ksft_test_result_error(const char *msg, ...)
 	va_end(args);
 }
 
+static inline __printf(2, 3)
+void ksft_test_result_code(int exit_code, const char *msg, ...)
+{
+	const char *tap_code = "ok";
+	const char *directive = "";
+	int saved_errno = errno;
+	va_list args;
+
+	switch (exit_code) {
+	case KSFT_PASS:
+		ksft_cnt.ksft_pass++;
+		break;
+	case KSFT_XFAIL:
+		directive = " # XFAIL ";
+		ksft_cnt.ksft_xfail++;
+		break;
+	case KSFT_XPASS:
+		directive = " # XPASS ";
+		ksft_cnt.ksft_xpass++;
+		break;
+	case KSFT_SKIP:
+		directive = " # SKIP ";
+		ksft_cnt.ksft_xskip++;
+		break;
+	case KSFT_FAIL:
+	default:
+		tap_code = "not ok";
+		ksft_cnt.ksft_fail++;
+		break;
+	}
+
+	va_start(args, msg);
+	printf("%s %u%s", tap_code, ksft_test_num(), directive);
+	errno = saved_errno;
+	vprintf(msg, args);
+	va_end(args);
+}
+
 static inline int ksft_exit_pass(void)
 {
 	ksft_print_cnts();

tools/testing/selftests/kselftest_harness.h

@@ -1111,6 +1111,7 @@ void __run_test(struct __fixture_metadata *f,
 		struct __test_metadata *t)
 {
 	char test_name[LINE_MAX];
+	const char *diagnostic;
 
 	/* reset test struct */
 	t->exit_code = KSFT_PASS;
@@ -1140,9 +1141,13 @@ void __run_test(struct __fixture_metadata *f,
 	ksft_print_msg("         %4s  %s\n",
 		       __test_passed(t) ? "OK" : "FAIL", test_name);
 
+	if (t->results->reason[0])
+		diagnostic = t->results->reason;
+	else
+		diagnostic = "unknown";
+
 	if (t->exit_code == KSFT_SKIP)
-		ksft_test_result_skip("%s\n", t->results->reason[0] ?
-					t->results->reason : "unknown");
+		ksft_test_result_code(t->exit_code, "%s\n", diagnostic);
 	else
 		ksft_test_result(__test_passed(t), "%s\n", test_name);
 }