tests: add basics for dm_hash unit testing

Better code coverage.

test/unit/Makefile

@@ -1,4 +1,4 @@
-# Copyright (C) 2011-2018 Red Hat, Inc. All rights reserved.
+# Copyright (C) 2011-2024 Red Hat, Inc. All rights reserved.
 #
 # This file is part of LVM2.
 #
@@ -20,6 +20,7 @@ UNIT_SOURCE=\
 	test/unit/bcache_utils_t.c \
 	test/unit/bitset_t.c \
 	test/unit/config_t.c \
+	test/unit/dmhash_t.c \
 	test/unit/dmlist_t.c \
 	test/unit/dmstatus_t.c \
 	test/unit/framework.c \

test/unit/dmhash_t.c

@@ -0,0 +1,61 @@
+/*
+ * Copyright (C) 2024 Red Hat, Inc. All rights reserved.
+ *
+ * This file is part of LVM2.
+ *
+ * This copyrighted material is made available to anyone wishing to use,
+ * modify, copy, or redistribute it subject to the terms and conditions
+ * of the GNU General Public License v.2.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "units.h"
+#include "device_mapper/all.h"
+
+static void test_hash_insert(void *fixture)
+{
+	static const char _keys[] = { '1', '2', '3', '4', '5' };
+	static const long _vals[] = { 'a', 'b', 'c', 'd', 'e' };
+	struct dm_hash_node *node;
+	unsigned i;
+	struct dm_hash_table *hash = dm_hash_create(10);
+
+	T_ASSERT(hash);
+
+	for (i = 0; i < DM_ARRAY_SIZE(_keys); i++)
+		T_ASSERT(dm_hash_insert_binary(hash, &_keys[i], sizeof(_keys[0]), (void*)_vals[i]));
+
+	T_ASSERT(dm_hash_get_num_entries(hash) == DM_ARRAY_SIZE(_keys));
+
+	/* list unsorted elements */
+	for (node = dm_hash_get_first(hash);  node; node = dm_hash_get_next(hash, node), --i) {
+		const char *k = dm_hash_get_key(hash, node);
+		char key = k[0];
+		void *d = dm_hash_get_data(hash, node);
+		//long v = (long) d;
+		//printf("key: %c  val: %c\n", key, (char)v);
+
+		T_ASSERT(d == dm_hash_lookup_binary(hash, &key, sizeof(key)));
+	}
+
+	T_ASSERT(i == 0);
+	dm_hash_destroy(hash);
+}
+
+#define T(path, desc, fn) register_test(ts, "/base/data-struct/hash/" path, desc, fn)
+
+void dm_hash_tests(struct dm_list *all_tests)
+{
+	struct test_suite *ts = test_suite_create(NULL, NULL);
+	if (!ts) {
+		fprintf(stderr, "out of memory\n");
+		exit(1);
+	}
+
+	T("insert", "inserting hash elements", test_hash_insert);
+
+	dm_list_add(all_tests, &ts->list);
+}

test/unit/units.h

@@ -25,6 +25,7 @@ void bcache_utils_tests(struct dm_list *suites);
 void bitset_tests(struct dm_list *suites);
 void config_tests(struct dm_list *suites);
 void dm_list_tests(struct dm_list *suites);
+void dm_hash_tests(struct dm_list *suites);
 void dm_status_tests(struct dm_list *suites);
 void io_engine_tests(struct dm_list *suites);
 void percent_tests(struct dm_list *suites);
@@ -41,6 +42,7 @@ static inline void register_all_tests(struct dm_list *suites)
 	bitset_tests(suites);
 	config_tests(suites);
 	dm_list_tests(suites);
+	dm_hash_tests(suites);
 	dm_status_tests(suites);
 	io_engine_tests(suites);
 	percent_tests(suites);