[PATCH v3 5/7] kunit: kunit-test: Add test cases for logging very long lines

Richard Fitzgerald
2023-08-09T15:55:15Z

Add kunit_log_long_line_test() to test that logging a line longer than
the buffer fragment size doesn't truncate the line.

Add extra tests to kunit_log_newline_test() for lines longer than the
buffer fragment size.

Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
---
lib/kunit/kunit-test.c | 84 +++++++++++++++++++++++++++++++++++++++++-
1 file changed, 83 insertions(+), 1 deletion(-)

diff --git a/lib/kunit/kunit-test.c b/lib/kunit/kunit-test.c
index 9ac81828d018..c079550c3afd 100644
--- a/lib/kunit/kunit-test.c
+++ b/lib/kunit/kunit-test.c
@@ -609,7 +609,7 @@ static void kunit_log_newline_test(struct kunit *test)
{
struct kunit_suite suite;
struct kunit_log_frag *frag;
- char *p;
+ char *p, *line;

kunit_info(test, "Add newline\n");
if (test->log) {
@@ -635,6 +635,33 @@ static void kunit_log_newline_test(struct kunit *test)
KUNIT_ASSERT_NOT_ERR_OR_NULL(test, p);
KUNIT_EXPECT_NOT_NULL_MSG(test, strstr(p, "x12345678\n"),
"Newline not appended when fragment is full. Log is:\n'%s'", p);
+ kunit_kfree(test, p);
+
+ /* String that is much longer than a fragment */
+ line = kunit_kzalloc(test, sizeof(frag->buf) * 6, GFP_KERNEL);
+ KUNIT_ASSERT_NOT_ERR_OR_NULL(test, line);
+ memset(line, 'x', (sizeof(frag->buf) * 6) - 1);
+ kunit_log_append(suite.log, "%s", line);
+ p = get_concatenated_log(test, suite.log, NULL);
+ KUNIT_ASSERT_NOT_ERR_OR_NULL(test, p);
+ KUNIT_EXPECT_EQ(test, p[strlen(p) - 1], '\n');
+ KUNIT_EXPECT_NULL(test, strstr(p, "\n\n"));
+ kunit_kfree(test, p);
+
+ kunit_log_append(suite.log, "%s\n", line);
+ p = get_concatenated_log(test, suite.log, NULL);
+ KUNIT_ASSERT_NOT_ERR_OR_NULL(test, p);
+ KUNIT_EXPECT_EQ(test, p[strlen(p) - 1], '\n');
+ KUNIT_EXPECT_NULL(test, strstr(p, "\n\n"));
+ kunit_kfree(test, p);
+
+ line[strlen(line) - 1] = '\n';
+ kunit_log_append(suite.log, "%s", line);
+ p = get_concatenated_log(test, suite.log, NULL);
+ KUNIT_ASSERT_NOT_ERR_OR_NULL(test, p);
+ KUNIT_EXPECT_EQ(test, p[strlen(p) - 1], '\n');
+ KUNIT_EXPECT_NULL(test, strstr(p, "\n\n"));
+ kunit_kfree(test, p);
} else {
kunit_skip(test, "only useful when debugfs is enabled");
}
@@ -799,6 +826,60 @@ static void kunit_log_frag_sized_line_test(struct kunit *test)
#endif
}

+static void kunit_log_long_line_test(struct kunit *test)
+{
+#ifdef CONFIG_KUNIT_DEBUGFS
+ struct kunit_suite suite;
+ struct kunit_log_frag *frag;
+ struct rnd_state rnd;
+ char *line, *p, *pn;
+ size_t line_buf_size, len;
+ int num_frags, i;
+
+ suite.log = kunit_kzalloc(test, sizeof(*suite.log), GFP_KERNEL);
+ KUNIT_ASSERT_NOT_ERR_OR_NULL(test, suite.log);
+ INIT_LIST_HEAD(suite.log);
+ frag = kunit_kmalloc(test, sizeof(*frag), GFP_KERNEL);
+ KUNIT_ASSERT_NOT_ERR_OR_NULL(test, frag);
+ kunit_init_log_frag(frag);
+ KUNIT_EXPECT_EQ(test, frag->buf[0], '\0');
+ list_add_tail(&frag->list, suite.log);
+
+ /* Create a very long string to be logged */
+ line_buf_size = sizeof(frag->buf) * 6;
+ line = kunit_kmalloc(test, line_buf_size, GFP_KERNEL);
+ KUNIT_ASSERT_NOT_ERR_OR_NULL(test, line);
+ line[0] = '\0';
+
+ prandom_seed_state(&rnd, 3141592653589793238ULL);
+ len = 0;
+ do {
+ static const char fill[] =
+ "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
+
+ i = prandom_u32_state(&rnd) % (sizeof(fill) - 1);
+ len = strlcat(line, &fill[i], line_buf_size);
+ } while (len < line_buf_size);
+
+ kunit_log_append(suite.log, "%s\n", line);
+
+ p = get_concatenated_log(test, suite.log, &num_frags);
+ KUNIT_ASSERT_NOT_ERR_OR_NULL(test, p);
+ KUNIT_EXPECT_GT(test, num_frags, 1);
+
+ kunit_info(test, "num_frags:%d total len:%zu\n", num_frags, strlen(p));
+
+ /* Don't compare the trailing '\n' */
+ pn = strrchr(p, '\n');
+ KUNIT_EXPECT_NOT_ERR_OR_NULL(test, pn);
+ *pn = '\0';
+ KUNIT_EXPECT_EQ(test, strlen(p), strlen(line));
+ KUNIT_EXPECT_STREQ(test, p, line);
+#else
+ kunit_skip(test, "only useful when debugfs is enabled");
+#endif
+}
+
static struct kunit_case kunit_log_test_cases[] = {
KUNIT_CASE(kunit_log_init_frag_test),
KUNIT_CASE(kunit_log_test),
@@ -806,6 +887,7 @@ static struct kunit_case kunit_log_test_cases[] = {
KUNIT_CASE(kunit_log_extend_test_1),
KUNIT_CASE(kunit_log_extend_test_2),
KUNIT_CASE(kunit_log_frag_sized_line_test),
+ KUNIT_CASE(kunit_log_long_line_test),
{}
};

--
2.30.2