tests: add utilities for cmocka based unit tests

Calls to list all tests and run only a single test are added.

Resolves: #6081

Reviewed-by: Iker Pedrosa <ipedrosa@redhat.com>
Reviewed-by: Tomáš Halman <thalman@redhat.com>

src/tests/cmocka/common_mock.h

@@ -53,4 +53,10 @@ enum sss_test_wrapper_call {
     WRAP_CALL_REAL
 };
 
+void list_tests(FILE *file, const char *pref,
+                const struct CMUnitTest tests[], size_t test_count);
+
+int sss_cmocka_run_group_tests(const struct CMUnitTest * const tests,
+                               const size_t num_tests,
+                               const char *single);
 #endif /* __COMMON_MOCK_H_ */

src/tests/cmocka/common_utils.c

@@ -0,0 +1,66 @@
+/*
+    Authors:
+        Sumit Bose <sbose@redhat.com>
+
+    Copyright (C) 2022 Red Hat
+
+    SSSD tests: common helpers
+
+    This program is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include "tests/cmocka/common_mock.h"
+
+static struct CMUnitTest select_test(const struct CMUnitTest tests[],
+                                     size_t test_count, const char *name)
+{
+    size_t c;
+    struct CMUnitTest empty = { 0 };
+
+    for (c = 0; c < test_count; c++) {
+        if (strcmp(tests[c].name, name) == 0) {
+            return tests[c];
+        }
+    }
+
+    return empty;
+}
+
+void list_tests(FILE *file, const char *pref,
+                const struct CMUnitTest tests[], size_t test_count)
+{
+    size_t c;
+    for (c = 0; c < test_count; c++) {
+        fprintf(file, "%s %s\n", pref == NULL ? "" : pref, tests[c].name);
+    }
+}
+
+int sss_cmocka_run_group_tests(const struct CMUnitTest * const tests,
+                               const size_t num_tests,
+                               const char *single)
+{
+    struct CMUnitTest single_test[1];
+
+    if (single != NULL) {
+        single_test[0] = select_test(tests, num_tests, single);
+        if (single_test[0].name == NULL) {
+            fprintf(stderr, "\nTest [%s] not available.\n\n", single);
+            return ENOENT;
+        }
+
+        return _cmocka_run_group_tests("single_test", single_test, 1,
+                                      NULL, NULL);
+    }
+    return _cmocka_run_group_tests("tests", tests, num_tests, NULL, NULL);
+}