3 * @brief Implementation of sensor thread
4 * TODO: Finalise implementation
13 /** Array of sensors, initialised by Sensor_Init **/
14 static Sensor g_sensors[NUMSENSORS]; //global to this file
16 /** Array of sensor threshold structures defining the safety values of each sensor**/
17 const SensorThreshold thresholds[NUMSENSORS]= {
18 //Max Safety, Min safety, Max warning, Min warning
19 {1,-1,1,-1}, // ANALOG_TEST0
20 {500,0,499,0}, // ANALOG_TEST1
21 {5,-5,4,-4}, // ANALOG_FAIL0
22 {1,0,1,0}, // DIGITAL_TEST0
23 {1,0,1,0}, // DIGITAL_TEST1
24 {1,0,1,0} // DIGITAL_FAIL0
27 /** Human readable names for the sensors **/
28 const char * g_sensor_names[NUMSENSORS] = {
29 "analog_test0", "analog_test1",
30 "analog_fail0", "digital_test0",
31 "digital_test1", "digital_fail0"
35 * One off initialisation of *all* sensors
39 for (int i = 0; i < NUMSENSORS; ++i)
42 Data_Init(&(g_sensors[i].data_file));
43 g_sensors[i].record_data = false;
48 * Start a Sensor recording DataPoints
49 * @param s - The Sensor to start
50 * @param experiment_name - Prepended to DataFile filename
52 void Sensor_Start(Sensor * s, const char * experiment_name)
55 char filename[BUFSIZ];
56 if (sprintf(filename, "%s_s%d", experiment_name, s->id) >= BUFSIZ)
58 Fatal("Experiment name \"%s\" too long (>%d)", experiment_name, BUFSIZ);
61 Log(LOGDEBUG, "Sensor %d with DataFile \"%s\"", s->id, filename);
63 Data_Open(&(s->data_file), filename);
65 s->record_data = true; // Don't forget this!
68 pthread_create(&(s->thread), NULL, Sensor_Loop, (void*)(s));
72 * Stop a Sensor from recording DataPoints. Blocks until it has stopped.
73 * @param s - The Sensor to stop
75 void Sensor_Stop(Sensor * s)
80 s->record_data = false;
81 pthread_join(s->thread, NULL); // Wait for thread to exit
82 Data_Close(&(s->data_file)); // Close DataFile
83 s->newest_data.time_stamp = 0;
84 s->newest_data.value = 0;
93 for (int i = 0; i < NUMSENSORS; ++i)
94 Sensor_Stop(g_sensors+i);
100 void Sensor_StartAll(const char * experiment_name)
102 for (int i = 0; i < NUMSENSORS; ++i)
103 Sensor_Start(g_sensors+i, experiment_name);
108 * Checks the sensor data for unsafe or unexpected results
109 * @param sensor_id - The ID of the sensor
110 * @param value - The value from the sensor to test
112 void Sensor_CheckData(SensorId id, double value)
114 if( value > thresholds[id].max_error || value < thresholds[id].min_error)
116 Log(LOGERR, "Sensor %s is above or below its safety value of %f or %f\n", g_sensor_names[id],thresholds[id].max_error, thresholds[id].min_error);
117 //new function that stops actuators?
119 else if( value > thresholds[id].max_warn || value < thresholds[id].min_warn)
121 Log(LOGWARN, "Sensor %s is above or below its warning value of %f or %f\n", g_sensor_names[id],thresholds[id].max_warn, thresholds[id].min_warn);
127 * Read a DataPoint from a Sensor; block until value is read
128 * @param id - The ID of the sensor
129 * @param d - DataPoint to set
130 * @returns True if the DataPoint was different from the most recently recorded.
132 bool Sensor_Read(Sensor * s, DataPoint * d)
137 gettimeofday(&t, NULL);
138 d->time_stamp = TIMEVAL_DIFF(t, g_options.start_time);
140 // Read value based on Sensor Id
144 d->value = (double)(rand() % 100) / 100;
148 static int count = 0;
154 d->value = (double)(rand() % 6) * -( rand() % 2) / ( rand() % 100 + 1);
155 //Gives a value between -5 and 5
158 d->value = t.tv_sec % 2;
161 d->value = (t.tv_sec+1)%2;
164 if( rand() % 100 > 98)
166 d->value = rand() % 2;
167 //Gives 0 or 1 or a 2 every 1/100 times
170 Fatal("Unknown sensor id: %d", s->id);
173 usleep(100000); // simulate delay in sensor polling
175 // Perform sanity check based on Sensor's ID and the DataPoint
176 Sensor_CheckData(s->id, d->value);
178 // Update latest DataPoint if necessary
179 bool result = (d->value != s->newest_data.value);
182 s->newest_data.time_stamp = d->time_stamp;
183 s->newest_data.value = d->value;
189 * Record data from a single Sensor; to be run in a seperate thread
190 * @param arg - Cast to Sensor* - Sensor that the thread will handle
191 * @returns NULL (void* required to use the function with pthreads)
193 void * Sensor_Loop(void * arg)
195 Sensor * s = (Sensor*)(arg);
196 Log(LOGDEBUG, "Sensor %d starts", s->id);
198 // Until the sensor is stopped, record data points
199 while (s->record_data)
202 //Log(LOGDEBUG, "Sensor %d reads data [%f,%f]", s->id, d.time_stamp, d.value);
203 if (Sensor_Read(s, &d)) // If new DataPoint is read:
205 //Log(LOGDEBUG, "Sensor %d saves data [%f,%f]", s->id, d.time_stamp, d.value);
206 Data_Save(&(s->data_file), &d, 1); // Record it
210 // Needed to keep pthreads happy
212 Log(LOGDEBUG, "Sensor %d finished", s->id);
217 * Get a Sensor given an ID string
218 * @param id_str ID string
219 * @returns Sensor* identified by the string; NULL on error
221 Sensor * Sensor_Identify(const char * id_str)
224 // Parse string as integer
225 int id = strtol(id_str, &end, 10);
231 if (id < 0 || id >= NUMSENSORS)
235 Log(LOGDEBUG, "Sensor \"%s\" identified", g_sensor_names[id]);
240 * Helper: Begin sensor response in a given format
241 * @param context - the FCGIContext
242 * @param id - ID of sensor
243 * @param format - Format
245 void Sensor_BeginResponse(FCGIContext * context, SensorId id, DataFormat format)
251 FCGI_BeginJSON(context, STATUS_OK);
252 FCGI_JSONLong("id", id);
255 FCGI_PrintRaw("Content-type: text/plain\r\n\r\n");
261 * Helper: End sensor response in a given format
262 * @param context - the FCGIContext
263 * @param id - ID of the sensor
264 * @param format - Format
266 void Sensor_EndResponse(FCGIContext * context, SensorId id, DataFormat format)
280 * Handle a request to the sensor module
281 * @param context - The context to work in
282 * @param params - Parameters passed
284 void Sensor_Handler(FCGIContext *context, char * params)
287 gettimeofday(&now, NULL);
288 double current_time = TIMEVAL_DIFF(now, g_options.start_time);
291 double start_time = 0;
292 double end_time = current_time;
293 const char * fmt_str;
296 FCGIValue values[] = {
297 {"id", &id, FCGI_REQUIRED(FCGI_INT_T)},
298 {"format", &fmt_str, FCGI_STRING_T},
299 {"start_time", &start_time, FCGI_DOUBLE_T},
300 {"end_time", &end_time, FCGI_DOUBLE_T},
303 // enum to avoid the use of magic numbers
311 // Fill values appropriately
312 if (!FCGI_ParseRequest(context, params, values, sizeof(values)/sizeof(FCGIValue)))
314 // Error occured; FCGI_RejectJSON already called
318 // Error checking on sensor id
319 if (id < 0 || id >= NUMSENSORS)
321 FCGI_RejectJSON(context, "Invalid sensor id");
324 Sensor * s = g_sensors+id;
326 DataFormat format = Data_GetFormat(&(values[FORMAT]));
331 Sensor_BeginResponse(context, id, format);
334 Data_Handler(&(s->data_file), &(values[START_TIME]), &(values[END_TIME]), format, current_time);
337 Sensor_EndResponse(context, id, format);
343 FCGI_RejectJSON(context, "Experiment is not running.");