Added app data handler to c-if and check function pointer

comm/commands.c

@@ -1723,8 +1723,13 @@ disp_pos_mode commands_get_disp_pos_mode(void) {
 	return display_position_mode;
 }
 
-void commands_set_app_data_handler(void(*func)(unsigned char *data, unsigned int len)) {
+bool commands_set_app_data_handler(void(*func)(unsigned char *data, unsigned int len)) {
-	appdata_func = func;
+	if (utils_is_func_valid(func)) {
+		appdata_func = func;
+		return true;
+	}
+
+	return false;
 }
 
 void commands_set_hw_data_handler(void(*func)(unsigned char *data, unsigned int len)) {

comm/commands.h

@@ -37,7 +37,7 @@ void commands_send_rotor_pos(float rotor_pos);
 void commands_send_experiment_samples(float *samples, int len);
 void commands_fwd_can_frame(int len, unsigned char *data, uint32_t id, bool is_extended);
 disp_pos_mode commands_get_disp_pos_mode(void);
-void commands_set_app_data_handler(void(*func)(unsigned char *data, unsigned int len));
+bool commands_set_app_data_handler(void(*func)(unsigned char *data, unsigned int len));
 void commands_set_hw_data_handler(void(*func)(unsigned char *data, unsigned int len));
 void commands_send_app_data(unsigned char *data, unsigned int len);
 void commands_send_hw_data(unsigned char *data, unsigned int len);

lispBM/c_libs/vesc_c_if.h

@@ -389,6 +389,9 @@ typedef struct {
 
 	// Settings (TODO: Add more types and also setters)
 	float (*get_cfg_float)(CFG_PARAM p);
+
+	// Add handler for received app data
+	bool (*set_app_data_handler)(void(*func)(unsigned char *data, unsigned int len));
 } vesc_c_if;
 
 typedef struct {

lispBM/lispif_c_lib.c

@@ -608,6 +608,9 @@ lbm_value ext_load_native_lib(lbm_value *args, lbm_uint argn) {
 		// Settings
 		cif.cif.get_cfg_float = lib_get_cfg_float;
 
+		// Add handler for received app data
+		cif.cif.set_app_data_handler = commands_set_app_data_handler;
+
 		lib_init_done = true;
 	}