extdom: add add_err_msg() with test

Reviewed-By: Jakub Hrozek <jhrozek@redhat.com>

daemons/ipa-slapi-plugins/ipa-extdom-extop/ipa_extdom.h

@@ -185,4 +185,5 @@ int getgrnam_r_wrapper(size_t buf_max, const char *name,
                        struct group *grp, char **_buf, size_t *_buf_len);
 int getgrgid_r_wrapper(size_t buf_max, gid_t gid,
                        struct group *grp, char **_buf, size_t *_buf_len);
+void set_err_msg(struct extdom_req *req, const char *format, ...);
 #endif /* _IPA_EXTDOM_H_ */

daemons/ipa-slapi-plugins/ipa-extdom-extop/ipa_extdom_cmocka_tests.c

@@ -213,6 +213,47 @@ void test_getgrgid_r_wrapper(void **state)
     free(buf);
 }
 
+void extdom_req_setup(void **state)
+{
+    struct extdom_req *req;
+
+    req = calloc(sizeof(struct extdom_req), 1);
+    assert_non_null(req);
+
+    *state = req;
+}
+
+void extdom_req_teardown(void **state)
+{
+    struct extdom_req *req;
+
+    req = (struct extdom_req *) *state;
+
+    free_req_data(req);
+}
+
+void test_set_err_msg(void **state)
+{
+    struct extdom_req *req;
+
+    req = (struct extdom_req *) *state;
+    assert_null(req->err_msg);
+
+    set_err_msg(NULL, NULL);
+    assert_null(req->err_msg);
+
+    set_err_msg(req, NULL);
+    assert_null(req->err_msg);
+
+    set_err_msg(req, "Test [%s][%d].", "ABCD", 1234);
+    assert_non_null(req->err_msg);
+    assert_string_equal(req->err_msg, "Test [ABCD][1234].");
+
+    set_err_msg(req, "2nd Test [%s][%d].", "ABCD", 1234);
+    assert_non_null(req->err_msg);
+    assert_string_equal(req->err_msg, "Test [ABCD][1234].");
+}
+
 int main(int argc, const char *argv[])
 {
     const UnitTest tests[] = {
@@ -220,6 +261,8 @@ int main(int argc, const char *argv[])
         unit_test(test_getpwuid_r_wrapper),
         unit_test(test_getgrnam_r_wrapper),
         unit_test(test_getgrgid_r_wrapper),
+        unit_test_setup_teardown(test_set_err_msg,
+                                 extdom_req_setup, extdom_req_teardown),
     };
 
     return run_tests(tests);

daemons/ipa-slapi-plugins/ipa-extdom-extop/ipa_extdom_common.c

@@ -229,6 +229,29 @@ done:
     return ret;
 }
 
+void set_err_msg(struct extdom_req *req, const char *format, ...)
+{
+    int ret;
+    va_list ap;
+
+    if (req == NULL) {
+        return;
+    }
+
+    if (format == NULL || req->err_msg != NULL) {
+        /* Do not override an existing error message. */
+        return;
+    }
+    va_start(ap, format);
+
+    ret = vasprintf(&req->err_msg, format, ap);
+    if (ret == -1) {
+        req->err_msg = strdup("vasprintf failed.\n");
+    }
+
+    va_end(ap);
+}
+
 int parse_request_data(struct berval *req_val, struct extdom_req **_req)
 {
     BerElement *ber = NULL;