1 files changed, 67 insertions, 0 deletions
diff --git a/src/lib/test-random.c b/src/lib/test-random.c
new file mode 100644
index 0000000..6c83ff6
--- /dev/null
+++ b/src/lib/test-random.c
@@ -0,0 +1,67 @@
+/* Copyright (c) 2018 Dovecot authors, see the included COPYING file */
+
+#include "test-lib.h"
+#include "stats-dist.h"
+#include "randgen.h"
+#include <math.h>
+
+#define TEST_RAND_SIZE_MEDIAN 100000.0
+
+static void test_random_median(void)
+{
+	uint64_t tmp;
+	double median, average;
+
+	struct stats_dist *s = stats_dist_init_with_size(TEST_RAND_SIZE_MEDIAN);
+	test_begin("test_random (median & average)");
+	for(unsigned int i = 0; i < TEST_RAND_SIZE_MEDIAN; i++) {
+		uint64_t value;
+		value = i_rand_limit(TEST_RAND_SIZE_MEDIAN);
+		stats_dist_add(s, value);
+	}
+	tmp = stats_dist_get_median(s);
+
+	/* median should be 0.5 +-2% */
+	median = (double)tmp / TEST_RAND_SIZE_MEDIAN;
+	test_assert(fabs(median - 0.5) < 0.01);
+
+	/* average should be 0.5 +- %2 */
+	average = stats_dist_get_avg(s) / TEST_RAND_SIZE_MEDIAN;
+
+	test_assert(fabs(average - 0.5) < 0.01);
+
+	stats_dist_deinit(&s);
+	test_end();
+}
+
+static void test_random_limits(void)
+{
+	test_begin("random limits");
+	test_assert(i_rand_limit(1) == 0);
+	test_assert(i_rand_minmax(0, 0) == 0);
+	test_assert(i_rand_minmax(UINT32_MAX, UINT32_MAX) == UINT32_MAX);
+	test_end();
+}
+
+void test_random(void)
+{
+	test_random_median();
+	test_random_limits();
+}
+
+enum fatal_test_state fatal_random(unsigned int stage)
+{
+	switch (stage) {
+	case 0:
+		test_begin("random fatals");
+		test_expect_fatal_string("min_val <= max_val");
+		(void)i_rand_minmax(1, 0);
+		return FATAL_TEST_FAILURE;
+	case 1:
+		test_expect_fatal_string("upper_bound > 0");
+		(void)i_rand_limit(0);
+		return FATAL_TEST_FAILURE;
+	}
+	test_end();
+	return FATAL_TEST_FINISHED;
+}