Fix 'test-query_timeout-t' by taking into account 'mysql-poll_timeout'

test/tap/tests/test-query_timeout-t.cpp

@@ -17,6 +17,7 @@ inline unsigned long long monotonic_time() {
   return (((unsigned long long) ts.tv_sec) * 1000000) + (ts.tv_nsec / 1000);
 }
 
+using std::string;
 
 int main(int argc, char** argv) {
 	CommandLine cl;
@@ -31,11 +32,44 @@ int main(int argc, char** argv) {
 		return exit_status();
 
 	if (!mysql_real_connect(mysql, cl.host, cl.username, cl.password, NULL, cl.port, NULL, 0)) {
-	    fprintf(stderr, "Failed to connect to database: Error: %s\n",
-	              mysql_error(mysql));
+	    fprintf(stderr, "Failed to connect to database: Error: %s\n", mysql_error(mysql));
 		return exit_status();
 	}
 
+	MYSQL* admin = mysql_init(NULL);
+	if (!admin) {
+	    fprintf(stderr, "Failed 'mysql_init'\n");
+		return exit_status();
+	}
+
+	if (!mysql_real_connect(admin, cl.host, cl.admin_username, cl.admin_password, NULL, cl.admin_port, NULL, 0)) {
+	    fprintf(stderr, "Failed to connect to Admin: Error: %s\n", mysql_error(admin));
+		return exit_status();
+	}
+
+	const string poll_query { "SELECT variable_value FROM global_variables WHERE variable_name='mysql-poll_timeout'" };
+	MYSQL_RES* res = nullptr;
+	MYSQL_ROW row = nullptr;
+	int poll_timeout = 0;
+
+	int q_res = mysql_query(admin, poll_query.c_str());
+	if (q_res) {
+	    fprintf(stderr, "Query '%s' failed with error '%s'\n", poll_query.c_str(), mysql_error(admin));
+		goto cleanup;
+	}
+
+	res = mysql_store_result(admin);
+	row = mysql_fetch_row(res);
+
+	if (row == nullptr || row[0] == nullptr) {
+	    fprintf(stderr, "Query '%s' failed to retrive 'mysql-poll_timeout' value. Empty row received.\n", poll_query.c_str());
+		goto cleanup;
+	}
+
+	poll_timeout = std::strtol(row[0], NULL, 10);
+
+	{
+
 	const char *q = "SELECT /* query_timeout=3300 */ SLEEP(20)";
 	diag("Running query; %s", q);
 	unsigned long long begin = monotonic_time();
@@ -45,9 +79,20 @@ int main(int argc, char** argv) {
 	unsigned long long end = monotonic_time();
 
 	unsigned long time_diff_ms = (end-begin)/1000;
+	// NOTE: We give a grace period of 150 extra ms. This value could be much lower.
+	unsigned long max_poll_to_ms = (3300 + poll_timeout + 150);
+
+	ok(
+		time_diff_ms > 3100 && time_diff_ms < max_poll_to_ms,
+		"Query should be interrupted at around 3300ms with a failure timeout at '%lu'ms. Exact time: %lums",
+		max_poll_to_ms, time_diff_ms
+	);
+
+	}
 
-	ok(time_diff_ms>3100 && time_diff_ms<5000 , "Query should be interrupted at around 3300ms . Exact time: %llums", time_diff_ms);
+cleanup:
 
+	mysql_close(admin);
 	mysql_close(mysql);
 
 	return exit_status();