1 files changed, 88 insertions, 0 deletions
diff --git a/regressions/ck_ec/validate/prop_test_timeutil_add_ns.c b/regressions/ck_ec/validate/prop_test_timeutil_add_ns.c
new file mode 100644
index 0000000..b62e1c7
--- /dev/null
+++ b/regressions/ck_ec/validate/prop_test_timeutil_add_ns.c
@@ -0,0 +1,88 @@
+#include <assert.h>
+
+#include "../../../src/ck_ec_timeutil.h"
+#include "fuzz_harness.h"
+
+#if ULONG_MAX > 4294967295
+typedef unsigned __int128 dword_t;
+#else
+typedef uint64_t dword_t;
+#endif
+
+struct example {
+	struct timespec ts;
+	uint32_t ns;
+};
+
+static const struct example examples[] = {
+	{
+		{
+			42,
+			100
+		},
+		1
+	},
+	{
+		{
+			42,
+			100
+		},
+		2 * NSEC_MAX
+	},
+	{
+		{
+			42,
+			NSEC_MAX
+		},
+		NSEC_MAX
+	},
+	{
+		{
+			TIME_MAX - 1,
+			1000
+		},
+		2 * NSEC_MAX
+	}
+};
+
+static inline int test_timespec_add_ns(const struct example *example)
+{
+	struct timespec ts = {
+		.tv_sec = example->ts.tv_sec,
+		.tv_nsec = example->ts.tv_nsec
+	};
+	const uint32_t ns = example->ns;
+
+	if (ts.tv_sec < 0) {
+		ts.tv_sec = ~ts.tv_sec;
+	}
+
+	if (ts.tv_nsec < 0) {
+		ts.tv_nsec = ~ts.tv_nsec;
+	}
+
+	ts.tv_nsec %= NSEC_MAX + 1;
+
+	const struct timespec actual = timespec_add_ns(ts, ns);
+
+	dword_t nanos =
+	    (dword_t)ts.tv_sec * (NSEC_MAX + 1) + ts.tv_nsec;
+
+	if (ns > NSEC_MAX) {
+		nanos += NSEC_MAX + 1;
+	} else {
+		nanos += ns;
+	}
+
+	if (nanos / (NSEC_MAX + 1) > TIME_MAX) {
+		assert(actual.tv_sec == TIME_MAX);
+		assert(actual.tv_nsec == NSEC_MAX);
+	} else {
+		assert(actual.tv_sec == (time_t)(nanos / (NSEC_MAX + 1)));
+		assert(actual.tv_nsec == (long)(nanos % (NSEC_MAX + 1)));
+	}
+
+	return 0;
+}
+
+TEST(test_timespec_add_ns, examples)