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_endhoop", STRAIN0, Strain_Read, Strain_Init, Strain_Cleanup, Strain_Sanity);
  88         Sensor_Add("strain1_endlong", STRAIN1, Strain_Read, Strain_Init, Strain_Cleanup, Strain_Sanity);
  89         Sensor_Add("strain2_midhoop", STRAIN2, Strain_Read, Strain_Init, Strain_Cleanup, Strain_Sanity);
  90         Sensor_Add("strain3_midlong", 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_pos", DIL_POS, Dilatometer_Read, Dilatometer_Init, Dilatometer_Cleanup, NULL);
  96         //Sensor_Add("dilatometer_diff",DIL_DIFF, Dilatometer_Read, Dilatometer_Init, Dilatometer_Cleanup, NULL);
  97 }
  98
  99 /**
 100  * Cleanup all sensors
 101  */
 102 void Sensor_Cleanup()
 103 {
 104         for (int i = 0; i < g_num_sensors; ++i)
 105         {
 106                 Sensor * s = g_sensors+i;
 107                 if (s->cleanup != NULL)
 108                         s->cleanup(s->user_id);
 109         }
 110         g_num_sensors = 0;
 111 }
 112
 113 /**
 114  * Sets the sensor to the desired control mode. No checks are
 115  * done to see if setting to the desired mode will conflict with
 116  * the current mode - the caller must guarantee this itself.
 117  * @param s The sensor whose mode is to be changed
 118  * @param mode The mode to be changed to
 119  * @param arg An argument specific to the mode to be set.
 120  *            e.g for CONTROL_START it represents the experiment name.
 121  */
 122 void Sensor_SetMode(Sensor * s, ControlModes mode, void * arg)
 123 {
 124         switch(mode)
 125         {
 126                 case CONTROL_START:
 127                         {
 128                                 // Set filename
 129                                 char filename[BUFSIZ];
 130                                 const char *experiment_path = (const char*) arg;
 131                                 int ret;
 132
 133                                 ret = snprintf(filename, BUFSIZ, "%s/sensor_%d", experiment_path, s->id);
 134
 135                                 if (ret >= BUFSIZ)
 136                                 {
 137                                         Fatal("Experiment path \"%s\" too long (%d, limit %d)",
 138                                                         experiment_path, ret, BUFSIZ);
 139                                 }
 140
 141                                 Log(LOGDEBUG, "Sensor %d with DataFile \"%s\"", s->id, filename);
 142                                 // Open DataFile
 143                                 Data_Open(&(s->data_file), filename);
 144                         }
 145                 case CONTROL_RESUME: //Case fallthrough, no break before
 146                         {
 147                                 int ret;
 148                                 s->activated = true; // Don't forget this!
 149
 150                                 // Create the thread
 151                                 ret = pthread_create(&(s->thread), NULL, Sensor_Loop, (void*)(s));
 152                                 if (ret != 0)
 153                                 {
 154                                         Fatal("Failed to create Sensor_Loop for Sensor %d", s->id);
 155                                 }
 156
 157                                 Log(LOGDEBUG, "Resuming sensor %d", s->id);
 158                         }
 159                 break;
 160
 161                 case CONTROL_EMERGENCY:
 162                 case CONTROL_PAUSE:
 163                         s->activated = false;
 164                         pthread_join(s->thread, NULL);
 165                         Log(LOGDEBUG, "Paused sensor %d", s->id);
 166                 break;
 167
 168                 case CONTROL_STOP:
 169                         if (s->activated) //May have been paused before
 170                         {
 171                                 s->activated = false;
 172                                 pthread_join(s->thread, NULL);
 173                         }
 174
 175                         Data_Close(&(s->data_file)); // Close DataFile
 176                         Log(LOGDEBUG, "Stopped sensor %d", s->id);
 177                 break;
 178                 default:
 179                         Fatal("Unknown control mode: %d", mode);
 180         }
 181 }
 182
 183 /**
 184  * Sets all sensors to the desired mode.
 185  * @see Sensor_SetMode for more information.
 186  * @param mode The mode to be changed to
 187  * @param arg An argument specific to the mode to be set.
 188  */
 189 void Sensor_SetModeAll(ControlModes mode, void * arg)
 190 {
 191         if (mode == CONTROL_START)
 192                 Sensor_Init();
 193         for (int i = 0; i < g_num_sensors; i++)
 194                 Sensor_SetMode(&g_sensors[i], mode, arg);
 195         if (mode == CONTROL_STOP)
 196                 Sensor_Cleanup();
 197 }
 198
 199
 200 /**
 201  * Record data from a single Sensor; to be run in a seperate thread
 202  * @param arg - Cast to Sensor* - Sensor that the thread will handle
 203  * @returns NULL (void* required to use the function with pthreads)
 204  */
 205 void * Sensor_Loop(void * arg)
 206 {
 207         Sensor * s = (Sensor*)(arg);
 208         Log(LOGDEBUG, "Sensor %d starts", s->id);
 209
 210         // Until the sensor is stopped, record data points
 211         while (s->activated)
 212         {
 213
 214                 bool success = s->read(s->user_id, &(s->current_data.value));
 215
 216                 struct timespec t;
 217                 clock_gettime(CLOCK_MONOTONIC, &t);
 218                 s->current_data.time_stamp = TIMEVAL_DIFF(t, *Control_GetStartTime());
 219
 220                 if (success)
 221                 {
 222                         if (s->sanity != NULL)
 223                         {
 224                                 if (!s->sanity(s->user_id, s->current_data.value))
 225                                 {
 226                                         Fatal("Sensor %s (%d,%d) reads unsafe value", s->name, s->id, s->user_id);
 227                                 }
 228                         }
 229                         s->averaged_data.time_stamp += s->current_data.time_stamp;
 230                         s->averaged_data.value = s->current_data.value;
 231
 232                         if (++(s->num_read) >= s->averages)
 233                         {
 234                                 s->averaged_data.time_stamp /= s->averages;
 235                                 s->averaged_data.value /= s->averages;
 236                                 Data_Save(&(s->data_file), &(s->averaged_data), 1); // Record it
 237                                 s->num_read = 0;
 238                                 s->averaged_data.time_stamp = 0;
 239                                 s->averaged_data.value = 0;
 240                         }
 241                 }
 242                 else
 243                 {
 244                         // Silence because strain sensors fail ~50% of the time :S
 245                         //Log(LOGWARN, "Failed to read sensor %s (%d,%d)", s->name, s->id,s->user_id);
 246                 }
 247
 248
 249                 clock_nanosleep(CLOCK_MONOTONIC, 0, &(s->sample_time), NULL);
 250
 251         }
 252
 253         // Needed to keep pthreads happy
 254         Log(LOGDEBUG, "Sensor %s (%d,%d) finished", s->name,s->id,s->user_id);
 255         return NULL;
 256 }
 257
 258 /**
 259  * Get a Sensor given its name
 260  * @returns Sensor with the given name, NULL if there isn't one
 261  */
 262 Sensor * Sensor_Identify(const char * name)
 263 {
 264         for (int i = 0; i < g_num_sensors; ++i)
 265         {
 266                 if (strcmp(g_sensors[i].name, name) == 0)
 267                         return &(g_sensors[i]);
 268         }
 269         return NULL;
 270 }
 271
 272 /**
 273  * Helper: Begin sensor response in a given format
 274  * @param context - the FCGIContext
 275  * @param id - ID of sensor
 276  * @param format - Format
 277  */
 278 void Sensor_BeginResponse(FCGIContext * context, Sensor * s, DataFormat format)
 279 {
 280         // Begin response
 281         switch (format)
 282         {
 283                 case JSON:
 284                         FCGI_BeginJSON(context, STATUS_OK);
 285                         FCGI_JSONLong("id", s->id);
 286                         FCGI_JSONLong("user_id", s->user_id); //NOTE: Might not want to expose this?
 287                         FCGI_JSONPair("name", s->name);
 288                         break;
 289                 default:
 290                         FCGI_PrintRaw("Content-type: text/plain\r\n\r\n");
 291                         break;
 292         }
 293 }
 294
 295 /**
 296  * Helper: End sensor response in a given format
 297  * @param context - the FCGIContext
 298  * @param id - ID of the sensor
 299  * @param format - Format
 300  */
 301 void Sensor_EndResponse(FCGIContext * context, Sensor * s, DataFormat format)
 302 {
 303         // End response
 304         switch (format)
 305         {
 306                 case JSON:
 307                         FCGI_EndJSON();
 308                         break;
 309                 default:
 310                         break;
 311         }
 312 }
 313
 314 /**
 315  * Handle a request to the sensor module
 316  * @param context - The context to work in
 317  * @param params - Parameters passed
 318  */
 319 void Sensor_Handler(FCGIContext *context, char * params)
 320 {
 321         struct timespec now;
 322         clock_gettime(CLOCK_MONOTONIC, &now);
 323         double current_time = TIMEVAL_DIFF(now, *Control_GetStartTime());
 324         int id = 0;
 325         const char * name = "";
 326         double start_time = 0;
 327         double end_time = current_time;
 328         const char * fmt_str;
 329         double sample_s = 0;
 330
 331         // key/value pairs
 332         FCGIValue values[] = {
 333                 {"id", &id, FCGI_INT_T},
 334                 {"name", &name, FCGI_STRING_T},
 335                 {"format", &fmt_str, FCGI_STRING_T},
 336                 {"start_time", &start_time, FCGI_DOUBLE_T},
 337                 {"end_time", &end_time, FCGI_DOUBLE_T},
 338                 {"sample_s", &sample_s, FCGI_DOUBLE_T}
 339         };
 340
 341         // enum to avoid the use of magic numbers
 342         typedef enum {
 343                 ID,
 344                 NAME,
 345                 FORMAT,
 346                 START_TIME,
 347                 END_TIME,
 348                 SAMPLE_S
 349         } SensorParams;
 350
 351         // Fill values appropriately
 352         if (!FCGI_ParseRequest(context, params, values, sizeof(values)/sizeof(FCGIValue)))
 353         {
 354                 // Error occured; FCGI_RejectJSON already called
 355                 return;
 356         }
 357
 358         Sensor * s = NULL;
 359         if (FCGI_RECEIVED(values[NAME].flags))
 360         {
 361                 if (FCGI_RECEIVED(values[ID].flags))
 362                 {
 363                         FCGI_RejectJSON(context, "Can't supply both sensor id and name");
 364                         return;
 365                 }
 366                 s = Sensor_Identify(name);
 367                 if (s == NULL)
 368                 {
 369                         FCGI_RejectJSON(context, "Unknown sensor name");
 370                         return;
 371                 }
 372         }
 373         else if (!FCGI_RECEIVED(values[ID].flags))
 374         {
 375                 FCGI_RejectJSON(context, "No sensor id or name supplied");
 376                 return;
 377         }
 378         else if (id < 0 || id >= g_num_sensors)
 379         {
 380                 FCGI_RejectJSON(context, "Invalid sensor id");
 381                 return;
 382         }
 383         else
 384         {
 385                 s = &(g_sensors[id]);
 386         }
 387
 388         // Adjust sample rate if necessary
 389         if (FCGI_RECEIVED(values[SAMPLE_S].flags))
 390         {
 391                 if (sample_s < 0)
 392                 {
 393                         FCGI_RejectJSON(context, "Negative sampling speed!");
 394                         return;
 395                 }
 396                 DOUBLE_TO_TIMEVAL(sample_s, &(s->sample_time));
 397         }
 398
 399
 400         DataFormat format = Data_GetFormat(&(values[FORMAT]));
 401
 402         // Begin response
 403         Sensor_BeginResponse(context, s, format);
 404
 405         // Print Data
 406         Data_Handler(&(s->data_file), &(values[START_TIME]), &(values[END_TIME]), format, current_time);
 407
 408         // Finish response
 409         Sensor_EndResponse(context, s, format);
 410
 411 }
 412
 413 /**
 414  * Get the Name of a Sensor
 415  * @param id - ID number
 416  */
 417 const char * Sensor_GetName(int id)
 418 {
 419         return g_sensors[id].name;
 420 }
 421
 422 DataPoint Sensor_LastData(int id)
 423 {
 424         Sensor * s = &(g_sensors[id]);
 425         return s->current_data;
 426 }
 427
 428