server/sensor.c

   1 /**
   2  * @file sensor.c
   3  * @brief Implementation of sensor thread
   4  * TODO: Finalise implementation
   5  */
   6
   7 #include "common.h"
   8 #include "sensor.h"
   9 #include "options.h"
  10 #include "bbb_pin.h"
  11 #include <math.h>
  12
  13 /** Array of sensors, initialised by Sensor_Init **/
  14 static Sensor g_sensors[SENSORS_MAX];
  15 /** The number of sensors **/
  16 int g_num_sensors = 0;
  17
  18
  19
  20 /**
  21  * Add and initialise a Sensor
  22  * @param name - Human readable name of the sensor
  23  * @param user_id - User identifier
  24  * @param read - Function to call whenever the sensor should be read
  25  * @param init - Function to call to initialise the sensor (may be NULL)
  26  * @param max_error - Maximum error threshold; program will exit if this is exceeded for the sensor reading
  27  * @param min_error - Minimum error threshold; program will exit if the sensor reading falls below this value
  28  * @param max_warn - Maximum warning threshold; program will log warnings if the value exceeds this threshold
  29  * @param min_warn - Minimum warning threshold; program will log warnings if the value falls below this threshold
  30  * @returns Number of actuators added so far
  31  */
  32 int Sensor_Add(const char * name, int user_id, ReadFn read, InitFn init, CleanFn cleanup, SanityFn sanity)
  33 {
  34         if (++g_num_sensors > SENSORS_MAX)
  35         {
  36                 Fatal("Too many sensors; Increase SENSORS_MAX from %d in sensor.h and recompile", SENSORS_MAX);
  37                 // We could design the program to use realloc(3)
  38                 // But since someone who adds a new sensor has to recompile the program anyway...
  39         }
  40         Sensor * s = &(g_sensors[g_num_sensors-1]);
  41
  42         s->id = g_num_sensors-1;
  43         s->user_id = user_id;
  44         Data_Init(&(s->data_file));
  45         s->name = name;
  46         s->read = read; // Set read function
  47         s->init = init; // Set init function
  48
  49         // Start by averaging values taken over a second
  50         DOUBLE_TO_TIMEVAL(1, &(s->sample_time));
  51         s->averages = 1;
  52         s->num_read = 0;
  53
  54         // Set sanity function
  55         s->sanity = sanity;
  56
  57         if (init != NULL)
  58         {
  59                 if (!init(name, user_id))
  60                         Fatal("Couldn't init sensor %s", name);
  61         }
  62
  63         s->current_data.time_stamp = 0;
  64         s->current_data.value = 0;
  65         s->averaged_data.time_stamp = 0;
  66         s->averaged_data.value = 0;
  67         return g_num_sensors;
  68 }
  69
  70 /**
  71  * Initialise all sensors used by the program
  72  * TODO: Edit this to add any extra sensors you need
  73  * TODO: Edit the includes as well
  74  */
  75 #include "sensors/resource.h"
  76 #include "sensors/strain.h"
  77 #include "sensors/pressure.h"
  78 #include "sensors/dilatometer.h"
  79 void Sensor_Init()
  80 {
  81         //Sensor_Add("cpu_stime", RESOURCE_CPU_SYS, Resource_Read, NULL, NULL, NULL);
  82         //Sensor_Add("cpu_utime", RESOURCE_CPU_USER, Resource_Read, NULL, NULL, NULL);
  83         Sensor_Add("pressure_high0", PRES_HIGH0, Pressure_Read, Pressure_Init, Pressure_Cleanup, NULL);
  84         Sensor_Add("pressure_high1", PRES_HIGH1, Pressure_Read, Pressure_Init, Pressure_Cleanup, NULL);
  85         Sensor_Add("pressure_low0", PRES_LOW0, Pressure_Read, Pressure_Init, Pressure_Cleanup, NULL);
  86         //Sensor_Add("../testing/count.py", 0, Piped_Read, Piped_Init, Piped_Cleanup, 1e50,-1e50,1e50,-1e50);
  87         Sensor_Add("strain0", STRAIN0, Strain_Read, Strain_Init, Strain_Cleanup, Strain_Sanity);
  88         Sensor_Add("strain1", STRAIN1, Strain_Read, Strain_Init, Strain_Cleanup, Strain_Sanity);
  89         Sensor_Add("strain2", STRAIN2, Strain_Read, Strain_Init, Strain_Cleanup, Strain_Sanity);
  90         Sensor_Add("strain3", STRAIN3, Strain_Read, Strain_Init, Strain_Cleanup, Strain_Sanity);
  91         //Sensor_Add("pressure0", PRESSURE0, Pressure_Read, Pressure_Init, 5000,0,5000,0);
  92         //Sensor_Add("pressure1", PRESSURE1, Pressure_Read, Pressure_Init, 5000,0,5000,0);
  93         //Sensor_Add("pressure_feedback", PRESSURE_FEEDBACK, Pressure_Read, Pressure_Init, 5000,0,5000,0);
  94         //Sensor_Add("enclosure", ENCLOSURE, Enclosure_Read, Enclosure_Init, 1,1,1,1);
  95         Sensor_Add("dilatometer", 0, Dilatometer_Read, Dilatometer_Init, Dilatometer_Cleanup, NULL);
  96 }
  97
  98 /**
  99  * Cleanup all sensors
 100  */
 101 void Sensor_Cleanup()
 102 {
 103         for (int i = 0; i < g_num_sensors; ++i)
 104         {
 105                 Sensor * s = g_sensors+i;
 106                 if (s->cleanup != NULL)
 107                         s->cleanup(s->user_id);
 108         }
 109         g_num_sensors = 0;
 110 }
 111
 112 /**
 113  * Sets the sensor to the desired control mode. No checks are
 114  * done to see if setting to the desired mode will conflict with
 115  * the current mode - the caller must guarantee this itself.
 116  * @param s The sensor whose mode is to be changed
 117  * @param mode The mode to be changed to
 118  * @param arg An argument specific to the mode to be set.
 119  *            e.g for CONTROL_START it represents the experiment name.
 120  */
 121 void Sensor_SetMode(Sensor * s, ControlModes mode, void * arg)
 122 {
 123         switch(mode)
 124         {
 125                 case CONTROL_START:
 126                         {
 127                                 // Set filename
 128                                 char filename[BUFSIZ];
 129                                 const char *experiment_path = (const char*) arg;
 130                                 int ret;
 131
 132                                 ret = snprintf(filename, BUFSIZ, "%s/sensor_%d", experiment_path, s->id);
 133
 134                                 if (ret >= BUFSIZ)
 135                                 {
 136                                         Fatal("Experiment path \"%s\" too long (%d, limit %d)",
 137                                                         experiment_path, ret, BUFSIZ);
 138                                 }
 139
 140                                 Log(LOGDEBUG, "Sensor %d with DataFile \"%s\"", s->id, filename);
 141                                 // Open DataFile
 142                                 Data_Open(&(s->data_file), filename);
 143                         }
 144                 case CONTROL_RESUME: //Case fallthrough, no break before
 145                         {
 146                                 int ret;
 147                                 s->activated = true; // Don't forget this!
 148
 149                                 // Create the thread
 150                                 ret = pthread_create(&(s->thread), NULL, Sensor_Loop, (void*)(s));
 151                                 if (ret != 0)
 152                                 {
 153                                         Fatal("Failed to create Sensor_Loop for Sensor %d", s->id);
 154                                 }
 155
 156                                 Log(LOGDEBUG, "Resuming sensor %d", s->id);
 157                         }
 158                 break;
 159
 160                 case CONTROL_EMERGENCY:
 161                 case CONTROL_PAUSE:
 162                         s->activated = false;
 163                         pthread_join(s->thread, NULL);
 164                         Log(LOGDEBUG, "Paused sensor %d", s->id);
 165                 break;
 166
 167                 case CONTROL_STOP:
 168                         if (s->activated) //May have been paused before
 169                         {
 170                                 s->activated = false;
 171                                 pthread_join(s->thread, NULL);
 172                         }
 173
 174                         Data_Close(&(s->data_file)); // Close DataFile
 175                         Log(LOGDEBUG, "Stopped sensor %d", s->id);
 176                 break;
 177                 default:
 178                         Fatal("Unknown control mode: %d", mode);
 179         }
 180 }
 181
 182 /**
 183  * Sets all sensors to the desired mode.
 184  * @see Sensor_SetMode for more information.
 185  * @param mode The mode to be changed to
 186  * @param arg An argument specific to the mode to be set.
 187  */
 188 void Sensor_SetModeAll(ControlModes mode, void * arg)
 189 {
 190         if (mode == CONTROL_START)
 191                 Sensor_Init();
 192         for (int i = 0; i < g_num_sensors; i++)
 193                 Sensor_SetMode(&g_sensors[i], mode, arg);
 194         if (mode == CONTROL_STOP)
 195                 Sensor_Cleanup();
 196 }
 197
 198
 199 /**
 200  * Record data from a single Sensor; to be run in a seperate thread
 201  * @param arg - Cast to Sensor* - Sensor that the thread will handle
 202  * @returns NULL (void* required to use the function with pthreads)
 203  */
 204 void * Sensor_Loop(void * arg)
 205 {
 206         Sensor * s = (Sensor*)(arg);
 207         Log(LOGDEBUG, "Sensor %d starts", s->id);
 208
 209         // Until the sensor is stopped, record data points
 210         while (s->activated)
 211         {
 212
 213                 bool success = s->read(s->user_id, &(s->current_data.value));
 214
 215                 struct timespec t;
 216                 clock_gettime(CLOCK_MONOTONIC, &t);
 217                 s->current_data.time_stamp = TIMEVAL_DIFF(t, *Control_GetStartTime());
 218
 219                 if (success)
 220                 {
 221                         if (s->sanity != NULL)
 222                         {
 223                                 if (!s->sanity(s->user_id, s->current_data.value))
 224                                 {
 225                                         Fatal("Sensor %s (%d,%d) reads unsafe value", s->name, s->id, s->user_id);
 226                                 }
 227                         }
 228                         s->averaged_data.time_stamp += s->current_data.time_stamp;
 229                         s->averaged_data.value = s->current_data.value;
 230
 231                         if (++(s->num_read) >= s->averages)
 232                         {
 233                                 s->averaged_data.time_stamp /= s->averages;
 234                                 s->averaged_data.value /= s->averages;
 235                                 Data_Save(&(s->data_file), &(s->averaged_data), 1); // Record it
 236                                 s->num_read = 0;
 237                                 s->averaged_data.time_stamp = 0;
 238                                 s->averaged_data.value = 0;
 239                         }
 240                 }
 241                 else
 242                 {
 243                         // Silence because strain sensors fail ~50% of the time :S
 244                         //Log(LOGWARN, "Failed to read sensor %s (%d,%d)", s->name, s->id,s->user_id);
 245                 }
 246
 247
 248                 clock_nanosleep(CLOCK_MONOTONIC, 0, &(s->sample_time), NULL);
 249
 250         }
 251
 252         // Needed to keep pthreads happy
 253         Log(LOGDEBUG, "Sensor %s (%d,%d) finished", s->name,s->id,s->user_id);
 254         return NULL;
 255 }
 256
 257 /**
 258  * Get a Sensor given its name
 259  * @returns Sensor with the given name, NULL if there isn't one
 260  */
 261 Sensor * Sensor_Identify(const char * name)
 262 {
 263         for (int i = 0; i < g_num_sensors; ++i)
 264         {
 265                 if (strcmp(g_sensors[i].name, name) == 0)
 266                         return &(g_sensors[i]);
 267         }
 268         return NULL;
 269 }
 270
 271 /**
 272  * Helper: Begin sensor response in a given format
 273  * @param context - the FCGIContext
 274  * @param id - ID of sensor
 275  * @param format - Format
 276  */
 277 void Sensor_BeginResponse(FCGIContext * context, Sensor * s, DataFormat format)
 278 {
 279         // Begin response
 280         switch (format)
 281         {
 282                 case JSON:
 283                         FCGI_BeginJSON(context, STATUS_OK);
 284                         FCGI_JSONLong("id", s->id);
 285                         FCGI_JSONLong("user_id", s->user_id); //NOTE: Might not want to expose this?
 286                         FCGI_JSONPair("name", s->name);
 287                         break;
 288                 default:
 289                         FCGI_PrintRaw("Content-type: text/plain\r\n\r\n");
 290                         break;
 291         }
 292 }
 293
 294 /**
 295  * Helper: End sensor response in a given format
 296  * @param context - the FCGIContext
 297  * @param id - ID of the sensor
 298  * @param format - Format
 299  */
 300 void Sensor_EndResponse(FCGIContext * context, Sensor * s, DataFormat format)
 301 {
 302         // End response
 303         switch (format)
 304         {
 305                 case JSON:
 306                         FCGI_EndJSON();
 307                         break;
 308                 default:
 309                         break;
 310         }
 311 }
 312
 313 /**
 314  * Handle a request to the sensor module
 315  * @param context - The context to work in
 316  * @param params - Parameters passed
 317  */
 318 void Sensor_Handler(FCGIContext *context, char * params)
 319 {
 320         struct timespec now;
 321         clock_gettime(CLOCK_MONOTONIC, &now);
 322         double current_time = TIMEVAL_DIFF(now, *Control_GetStartTime());
 323         int id = 0;
 324         const char * name = "";
 325         double start_time = 0;
 326         double end_time = current_time;
 327         const char * fmt_str;
 328         double sample_s = 0;
 329
 330         // key/value pairs
 331         FCGIValue values[] = {
 332                 {"id", &id, FCGI_INT_T},
 333                 {"name", &name, FCGI_STRING_T},
 334                 {"format", &fmt_str, FCGI_STRING_T},
 335                 {"start_time", &start_time, FCGI_DOUBLE_T},
 336                 {"end_time", &end_time, FCGI_DOUBLE_T},
 337                 {"sample_s", &sample_s, FCGI_DOUBLE_T}
 338         };
 339
 340         // enum to avoid the use of magic numbers
 341         typedef enum {
 342                 ID,
 343                 NAME,
 344                 FORMAT,
 345                 START_TIME,
 346                 END_TIME,
 347                 SAMPLE_S
 348         } SensorParams;
 349
 350         // Fill values appropriately
 351         if (!FCGI_ParseRequest(context, params, values, sizeof(values)/sizeof(FCGIValue)))
 352         {
 353                 // Error occured; FCGI_RejectJSON already called
 354                 return;
 355         }
 356
 357         Sensor * s = NULL;
 358         if (FCGI_RECEIVED(values[NAME].flags))
 359         {
 360                 if (FCGI_RECEIVED(values[ID].flags))
 361                 {
 362                         FCGI_RejectJSON(context, "Can't supply both sensor id and name");
 363                         return;
 364                 }
 365                 s = Sensor_Identify(name);
 366                 if (s == NULL)
 367                 {
 368                         FCGI_RejectJSON(context, "Unknown sensor name");
 369                         return;
 370                 }
 371         }
 372         else if (!FCGI_RECEIVED(values[ID].flags))
 373         {
 374                 FCGI_RejectJSON(context, "No sensor id or name supplied");
 375                 return;
 376         }
 377         else if (id < 0 || id >= g_num_sensors)
 378         {
 379                 FCGI_RejectJSON(context, "Invalid sensor id");
 380                 return;
 381         }
 382         else
 383         {
 384                 s = &(g_sensors[id]);
 385         }
 386
 387         // Adjust sample rate if necessary
 388         if (FCGI_RECEIVED(values[SAMPLE_S].flags))
 389         {
 390                 if (sample_s < 0)
 391                 {
 392                         FCGI_RejectJSON(context, "Negative sampling speed!");
 393                         return;
 394                 }
 395                 DOUBLE_TO_TIMEVAL(sample_s, &(s->sample_time));
 396         }
 397
 398
 399         DataFormat format = Data_GetFormat(&(values[FORMAT]));
 400
 401         // Begin response
 402         Sensor_BeginResponse(context, s, format);
 403
 404         // Print Data
 405         Data_Handler(&(s->data_file), &(values[START_TIME]), &(values[END_TIME]), format, current_time);
 406
 407         // Finish response
 408         Sensor_EndResponse(context, s, format);
 409
 410 }
 411
 412 /**
 413  * Get the Name of a Sensor
 414  * @param id - ID number
 415  */
 416 const char * Sensor_GetName(int id)
 417 {
 418         return g_sensors[id].name;
 419 }
 420
 421 DataPoint Sensor_LastData(int id)
 422 {
 423         Sensor * s = &(g_sensors[id]);
 424         return s->current_data;
 425 }
 426
 427