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 * Pause a sensor from recording DataPoints. Blocks until it is paused.
73 * @param s - The Sensor to pause
75 void Sensor_Pause(Sensor *s)
79 s->record_data = false;
80 pthread_join(s->thread, NULL);
85 * Resumes a paused sensor.
86 * @param s - The Sensor to resume
88 void Sensor_Resume(Sensor *s)
92 s->record_data = true;
93 pthread_create(&(s->thread), NULL, Sensor_Loop, (void*)(s));
98 * Stop a Sensor from recording DataPoints. Blocks until it has stopped.
99 * @param s - The Sensor to stop
101 void Sensor_Stop(Sensor * s)
104 Data_Close(&(s->data_file)); // Close DataFile
105 s->newest_data.time_stamp = 0;
106 s->newest_data.value = 0;
112 void Sensor_StopAll()
114 for (int i = 0; i < NUMSENSORS; ++i)
115 Sensor_Stop(g_sensors+i);
118 void Sensor_PauseAll()
120 for (int i = 0; i < NUMSENSORS; ++i)
121 Sensor_Pause(g_sensors+i);
124 void Sensor_ResumeAll()
126 for (int i = 0; i < NUMSENSORS; ++i)
127 Sensor_Resume(g_sensors+i);
133 void Sensor_StartAll(const char * experiment_name)
135 for (int i = 0; i < NUMSENSORS; ++i)
136 Sensor_Start(g_sensors+i, experiment_name);
141 * Checks the sensor data for unsafe or unexpected results
142 * @param sensor_id - The ID of the sensor
143 * @param value - The value from the sensor to test
145 void Sensor_CheckData(SensorId id, double value)
147 if( value > thresholds[id].max_error || value < thresholds[id].min_error)
149 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);
150 //new function that stops actuators?
152 else if( value > thresholds[id].max_warn || value < thresholds[id].min_warn)
154 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);
160 * Read a DataPoint from a Sensor; block until value is read
161 * @param id - The ID of the sensor
162 * @param d - DataPoint to set
163 * @returns True if the DataPoint was different from the most recently recorded.
165 bool Sensor_Read(Sensor * s, DataPoint * d)
170 gettimeofday(&t, NULL);
171 d->time_stamp = TIMEVAL_DIFF(t, *Control_GetStartTime());
173 // Read value based on Sensor Id
177 d->value = (double)(rand() % 100) / 100;
181 static int count = 0;
187 d->value = (double)(rand() % 6) * -( rand() % 2) / ( rand() % 100 + 1);
188 //Gives a value between -5 and 5
191 d->value = t.tv_sec % 2;
194 d->value = (t.tv_sec+1)%2;
197 if( rand() % 100 > 98)
199 d->value = rand() % 2;
200 //Gives 0 or 1 or a 2 every 1/100 times
203 Fatal("Unknown sensor id: %d", s->id);
206 usleep(100000); // simulate delay in sensor polling
208 // Perform sanity check based on Sensor's ID and the DataPoint
209 Sensor_CheckData(s->id, d->value);
211 // Update latest DataPoint if necessary
212 bool result = (d->value != s->newest_data.value);
215 s->newest_data.time_stamp = d->time_stamp;
216 s->newest_data.value = d->value;
222 * Record data from a single Sensor; to be run in a seperate thread
223 * @param arg - Cast to Sensor* - Sensor that the thread will handle
224 * @returns NULL (void* required to use the function with pthreads)
226 void * Sensor_Loop(void * arg)
228 Sensor * s = (Sensor*)(arg);
229 Log(LOGDEBUG, "Sensor %d starts", s->id);
231 // Until the sensor is stopped, record data points
232 while (s->record_data)
235 //Log(LOGDEBUG, "Sensor %d reads data [%f,%f]", s->id, d.time_stamp, d.value);
236 if (Sensor_Read(s, &d)) // If new DataPoint is read:
238 //Log(LOGDEBUG, "Sensor %d saves data [%f,%f]", s->id, d.time_stamp, d.value);
239 Data_Save(&(s->data_file), &d, 1); // Record it
243 // Needed to keep pthreads happy
245 Log(LOGDEBUG, "Sensor %d finished", s->id);
250 * Get a Sensor given an ID string
251 * @param id_str ID string
252 * @returns Sensor* identified by the string; NULL on error
254 Sensor * Sensor_Identify(const char * id_str)
257 // Parse string as integer
258 int id = strtol(id_str, &end, 10);
264 if (id < 0 || id >= NUMSENSORS)
268 Log(LOGDEBUG, "Sensor \"%s\" identified", g_sensor_names[id]);
273 * Helper: Begin sensor response in a given format
274 * @param context - the FCGIContext
275 * @param id - ID of sensor
276 * @param format - Format
278 void Sensor_BeginResponse(FCGIContext * context, SensorId id, DataFormat format)
284 FCGI_BeginJSON(context, STATUS_OK);
285 FCGI_JSONLong("id", id);
288 FCGI_PrintRaw("Content-type: text/plain\r\n\r\n");
294 * Helper: End sensor response in a given format
295 * @param context - the FCGIContext
296 * @param id - ID of the sensor
297 * @param format - Format
299 void Sensor_EndResponse(FCGIContext * context, SensorId id, DataFormat format)
313 * Handle a request to the sensor module
314 * @param context - The context to work in
315 * @param params - Parameters passed
317 void Sensor_Handler(FCGIContext *context, char * params)
320 gettimeofday(&now, NULL);
321 double current_time = TIMEVAL_DIFF(now, *Control_GetStartTime());
324 double start_time = 0;
325 double end_time = current_time;
326 const char * fmt_str;
329 FCGIValue values[] = {
330 {"id", &id, FCGI_REQUIRED(FCGI_INT_T)},
331 {"format", &fmt_str, FCGI_STRING_T},
332 {"start_time", &start_time, FCGI_DOUBLE_T},
333 {"end_time", &end_time, FCGI_DOUBLE_T},
336 // enum to avoid the use of magic numbers
344 // Fill values appropriately
345 if (!FCGI_ParseRequest(context, params, values, sizeof(values)/sizeof(FCGIValue)))
347 // Error occured; FCGI_RejectJSON already called
351 // Error checking on sensor id
352 if (id < 0 || id >= NUMSENSORS)
354 FCGI_RejectJSON(context, "Invalid sensor id");
357 Sensor * s = g_sensors+id;
359 DataFormat format = Data_GetFormat(&(values[FORMAT]));
362 Sensor_BeginResponse(context, id, format);
365 Data_Handler(&(s->data_file), &(values[START_TIME]), &(values[END_TIME]), format, current_time);
368 Sensor_EndResponse(context, id, format);