[PATCH] selftests: rtc: rtctest: Do not open-code TEST_HARNESS_MAIN

[Kees Cook <keescook@chromium.org>]

Argument processing is specific to the test harness code. Any optional
information needs to be passed via environment variables. Move alternate
path to the RTC_DEV environment variable. Also do not open-code
TEST_HARNESS_MAIN because its definition may change.

Additionally, setup checking can be done in the FIXTURE_SETUP(). With
this adjustment, also improve the error reporting when the device cannot
be opened.

Signed-off-by: Kees Cook <keescook@chromium.org>
---
Cc: Alexandre Belloni <alexandre.belloni@bootlin.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: linux-rtc@vger.kernel.org
Cc: linux-kselftest@vger.kernel.org
---
 tools/testing/selftests/rtc/Makefile  |  2 +-
 tools/testing/selftests/rtc/rtctest.c | 66 +++++----------------------
 2 files changed, 13 insertions(+), 55 deletions(-)

diff --git a/tools/testing/selftests/rtc/Makefile b/tools/testing/selftests/rtc/Makefile
index 55198ecc04db..654f9d58da3c 100644
--- a/tools/testing/selftests/rtc/Makefile
+++ b/tools/testing/selftests/rtc/Makefile
@@ -1,5 +1,5 @@
 # SPDX-License-Identifier: GPL-2.0
-CFLAGS += -O3 -Wl,-no-as-needed -Wall
+CFLAGS += -O3 -Wl,-no-as-needed -Wall $(KHDR_INCLUDES)
 LDLIBS += -lrt -lpthread -lm
 
 TEST_GEN_PROGS = rtctest
diff --git a/tools/testing/selftests/rtc/rtctest.c b/tools/testing/selftests/rtc/rtctest.c
index 63ce02d1d5cc..41cfefcc20e1 100644
--- a/tools/testing/selftests/rtc/rtctest.c
+++ b/tools/testing/selftests/rtc/rtctest.c
@@ -30,7 +30,18 @@ FIXTURE(rtc) {
 };
 
 FIXTURE_SETUP(rtc) {
+	char *alternate = getenv("RTC_DEV");
+
+	if (alternate)
+		rtc_file = alternate;
+
 	self->fd = open(rtc_file, O_RDONLY);
+
+	if (self->fd == -1 && errno == ENOENT)
+		SKIP(return, "Skipping test since %s does not exist", rtc_file);
+	EXPECT_NE(-1, self->fd) {
+		TH_LOG("%s: %s\n", rtc_file, strerror(errno));
+	}
 }
 
 FIXTURE_TEARDOWN(rtc) {
@@ -41,10 +52,6 @@ TEST_F(rtc, date_read) {
 	int rc;
 	struct rtc_time rtc_tm;
 
-	if (self->fd == -1 && errno == ENOENT)
-		SKIP(return, "Skipping test since %s does not exist", rtc_file);
-	ASSERT_NE(-1, self->fd);
-
 	/* Read the RTC time/date */
 	rc = ioctl(self->fd, RTC_RD_TIME, &rtc_tm);
 	ASSERT_NE(-1, rc);
@@ -88,10 +95,6 @@ TEST_F_TIMEOUT(rtc, date_read_loop, READ_LOOP_DURATION_SEC + 2) {
 	struct rtc_time rtc_tm;
 	time_t start_rtc_read, prev_rtc_read;
 
-	if (self->fd == -1 && errno == ENOENT)
-		SKIP(return, "Skipping test since %s does not exist", rtc_file);
-	ASSERT_NE(-1, self->fd);
-
 	TH_LOG("Continuously reading RTC time for %ds (with %dms breaks after every read).",
 	       READ_LOOP_DURATION_SEC, READ_LOOP_SLEEP_MS);
 
@@ -126,10 +129,6 @@ TEST_F_TIMEOUT(rtc, uie_read, NUM_UIE + 2) {
 	int i, rc, irq = 0;
 	unsigned long data;
 
-	if (self->fd == -1 && errno == ENOENT)
-		SKIP(return, "Skipping test since %s does not exist", rtc_file);
-	ASSERT_NE(-1, self->fd);
-
 	/* Turn on update interrupts */
 	rc = ioctl(self->fd, RTC_UIE_ON, 0);
 	if (rc == -1) {
@@ -155,10 +154,6 @@ TEST_F(rtc, uie_select) {
 	int i, rc, irq = 0;
 	unsigned long data;
 
-	if (self->fd == -1 && errno == ENOENT)
-		SKIP(return, "Skipping test since %s does not exist", rtc_file);
-	ASSERT_NE(-1, self->fd);
-
 	/* Turn on update interrupts */
 	rc = ioctl(self->fd, RTC_UIE_ON, 0);
 	if (rc == -1) {
@@ -198,10 +193,6 @@ TEST_F(rtc, alarm_alm_set) {
 	time_t secs, new;
 	int rc;
 
-	if (self->fd == -1 && errno == ENOENT)
-		SKIP(return, "Skipping test since %s does not exist", rtc_file);
-	ASSERT_NE(-1, self->fd);
-
 	rc = ioctl(self->fd, RTC_RD_TIME, &tm);
 	ASSERT_NE(-1, rc);
 
@@ -256,10 +247,6 @@ TEST_F(rtc, alarm_wkalm_set) {
 	time_t secs, new;
 	int rc;
 
-	if (self->fd == -1 && errno == ENOENT)
-		SKIP(return, "Skipping test since %s does not exist", rtc_file);
-	ASSERT_NE(-1, self->fd);
-
 	rc = ioctl(self->fd, RTC_RD_TIME, &alarm.time);
 	ASSERT_NE(-1, rc);
 
@@ -308,10 +295,6 @@ TEST_F_TIMEOUT(rtc, alarm_alm_set_minute, 65) {
 	time_t secs, new;
 	int rc;
 
-	if (self->fd == -1 && errno == ENOENT)
-		SKIP(return, "Skipping test since %s does not exist", rtc_file);
-	ASSERT_NE(-1, self->fd);
-
 	rc = ioctl(self->fd, RTC_RD_TIME, &tm);
 	ASSERT_NE(-1, rc);
 
@@ -366,10 +349,6 @@ TEST_F_TIMEOUT(rtc, alarm_wkalm_set_minute, 65) {
 	time_t secs, new;
 	int rc;
 
-	if (self->fd == -1 && errno == ENOENT)
-		SKIP(return, "Skipping test since %s does not exist", rtc_file);
-	ASSERT_NE(-1, self->fd);
-
 	rc = ioctl(self->fd, RTC_RD_TIME, &alarm.time);
 	ASSERT_NE(-1, rc);
 
@@ -410,25 +389,4 @@ TEST_F_TIMEOUT(rtc, alarm_wkalm_set_minute, 65) {
 	ASSERT_EQ(new, secs);
 }
 
-static void __attribute__((constructor))
-__constructor_order_last(void)
-{
-	if (!__constructor_order)
-		__constructor_order = _CONSTRUCTOR_ORDER_BACKWARD;
-}
-
-int main(int argc, char **argv)
-{
-	switch (argc) {
-	case 2:
-		rtc_file = argv[1];
-		/* FALLTHROUGH */
-	case 1:
-		break;
-	default:
-		fprintf(stderr, "usage: %s [rtcdev]\n", argv[0]);
-		return 1;
-	}
-
-	return test_harness_run(argc, argv);
-}
+TEST_HARNESS_MAIN
-- 
2.34.1