Add unit tests for cansdo module

test/Makefile

@@ -10,7 +10,7 @@ LDFLAGS     = -g
 BINARY		= test_libopeninv
 OBJS		= test_main.o fu.o test_fu.o test_fp.o my_fp.o my_string.o params.o \
 			  stub_canhardware.o test_canmap.o canmap.o test_linbus.o linbus.o \
-			  stub_libopencm3.o
+			  stub_libopencm3.o test_cansdo.o cansdo.o errormessage.o printf.o
 VPATH = ../src ../libopeninv/src
 
 # Check if the variable GITHUB_RUN_NUMBER exists. When running on the github actions running, this

test/test-include/errormessage_prj.h

@@ -0,0 +1,22 @@
+/*
+ * This file is part of the libopeninv project.
+ *
+ * Copyright (C) 2025 Johannes Huebner <dev@johanneshuebner.com>
+ *
+ * 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/>.
+ */
+
+// Minimal error message definitions for unit tests
+#define ERROR_MESSAGE_LIST
+#define ERROR_BUF_SIZE 10