+
+/**
+ * Sets the mode to the desired mode, if possible.
+ * @param desired_mode The mode to be set to
+ * @param arg An argument specific to the mode to be set.
+ * @return NULL on success, an error message on failure.
+ */
+const char* Control_SetMode(ControlModes desired_mode, void * arg)
+{
+ const char *ret = NULL;
+
+ pthread_mutex_lock(&(g_controls.mutex));
+ if (g_controls.current_mode == desired_mode)
+ ret = "Already in the desired mode.";
+ else if (g_controls.current_mode == CONTROL_EMERGENCY && desired_mode != CONTROL_STOP)
+ ret = "In emergency mode. You must stop before continuing.";
+ else switch (desired_mode) {
+ case CONTROL_START:
+ if (g_controls.current_mode == CONTROL_STOP) {
+ const char * name = arg;
+ if (!*name)
+ ret = "An experiment name must be specified";
+ else if (strpbrk(name, INVALID_CHARACTERS))
+ ret = "The experiment name must not contain: " INVALID_CHARACTERS_JSON;
+ else {
+ FILE *fp = fopen((const char*) arg, "a");
+ if (fp) {
+ fclose(fp);
+ gettimeofday(&(g_controls.start_time), NULL);
+ } else
+ ret = "Cannot open experiment name marker";
+ }
+ } else
+ ret = "Cannot start when not in a stopped state.";
+ break;
+ case CONTROL_PAUSE:
+ if (g_controls.current_mode != CONTROL_START)
+ ret = "Cannot pause when not in a running state.";
+ break;
+ case CONTROL_RESUME:
+ if (g_controls.current_mode != CONTROL_PAUSE)
+ ret = "Cannot resume when not in a paused state.";
+ break;
+ case CONTROL_EMERGENCY:
+ if (g_controls.current_mode != CONTROL_START) //pfft
+ ret = "Not running so how can there be an emergency.";
+ break;
+ default:
+ break;
+ }
+
+ if (ret == NULL) {
+ Actuator_SetModeAll(desired_mode, arg);
+ Sensor_SetModeAll(desired_mode, arg);
+ if (desired_mode != CONTROL_RESUME)
+ g_controls.current_mode = desired_mode;
+ else
+ g_controls.current_mode = CONTROL_START;
+ }
+ pthread_mutex_unlock(&(g_controls.mutex));
+ return ret;
+}
+
+/**
+ * Gets a string representation of the current mode
+ * @param mode The mode to get a string representation of
+ * @return The string representation of the mode
+ */
+const char * Control_GetModeName() {
+ const char * ret = "Unknown";
+
+ switch (g_controls.current_mode) {
+ case CONTROL_START: ret = "Running"; break;
+ case CONTROL_PAUSE: ret = "Paused"; break;
+ case CONTROL_RESUME: ret = "Resumed"; break;
+ case CONTROL_STOP: ret = "Stopped"; break;
+ case CONTROL_EMERGENCY: ret = "Emergency mode"; break;
+ }
+ return ret;
+}
+
+/**
+ * Gets the start time for the current experiment
+ * @return the start time
+ */
+const struct timeval* Control_GetStartTime() {
+ return &g_controls.start_time;
+}