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 cleanup - Function to call whenever to deinitialise the sensor (may be NULL)
  27  * @param sanity - Function to call to check that the sensor value is sane (may be NULL)
  28  * @returns Number of actuators added so far
  29  */
  30 int Sensor_Add(const char * name, int user_id, ReadFn read, InitFn init, CleanFn cleanup, SanityFn sanity)
  31 {
  32         if (++g_num_sensors > SENSORS_MAX)
  33         {
  34                 Fatal("Too many sensors; Increase SENSORS_MAX from %d in sensor.h and recompile", SENSORS_MAX);
  35                 // We could design the program to use realloc(3)
  36                 // But since someone who adds a new sensor has to recompile the program anyway...
  37         }
  38         Sensor * s = &(g_sensors[g_num_sensors-1]);
  39
  40         s->id = g_num_sensors-1;
  41         s->user_id = user_id;
  42         Data_Init(&(s->data_file));
  43         s->name = name;
  44         s->read = read; // Set read function
  45         s->init = init; // Set init function
  46
  47         // Start by averaging values taken over a second
  48         DOUBLE_TO_TIMEVAL(1, &(s->sample_time));
  49         s->averages = 1;
  50         s->num_read = 0;
  51
  52         // Set sanity function
  53         s->sanity = sanity;
  54
  55         if (init != NULL)
  56         {
  57                 if (!init(name, user_id))
  58                         Fatal("Couldn't init sensor %s", name);
  59         }
  60
  61         s->current_data.time_stamp = 0;
  62         s->current_data.value = 0;
  63         s->averaged_data.time_stamp = 0;
  64         s->averaged_data.value = 0;
  65         return g_num_sensors;
  66 }
  67
  68 /**
  69  * Initialise all sensors used by the program
  70  * TODO: Edit this to add any extra sensors you need
  71  * TODO: Edit the includes as well
  72  */
  73 #include "sensors/resource.h"
  74 #include "sensors/strain.h"
  75 #include "sensors/pressure.h"
  76 #include "sensors/dilatometer.h"
  77 #include "sensors/microphone.h"
  78 void Sensor_Init()
  79 {
  80         //Sensor_Add("cpu_stime", RESOURCE_CPU_SYS, Resource_Read, NULL, NULL, NULL);
  81         //Sensor_Add("cpu_utime", RESOURCE_CPU_USER, Resource_Read, NULL, NULL, NULL);
  82         Sensor_Add("pressure_high0", PRES_HIGH0, Pressure_Read, Pressure_Init, Pressure_Cleanup, NULL);
  83         Sensor_Add("pressure_high1", PRES_HIGH1, Pressure_Read, Pressure_Init, Pressure_Cleanup, NULL);
  84         Sensor_Add("pressure_low0", PRES_LOW0, Pressure_Read, Pressure_Init, Pressure_Cleanup, NULL);
  85         //Sensor_Add("../testing/count.py", 0, Piped_Read, Piped_Init, Piped_Cleanup, 1e50,-1e50,1e50,-1e50);
  86         //Sensor_Add("strain0_endhoop", STRAIN0, Strain_Read, Strain_Init, Strain_Cleanup, Strain_Sanity);
  87         //Sensor_Add("strain1_endlong", STRAIN1, Strain_Read, Strain_Init, Strain_Cleanup, Strain_Sanity);
  88         //Sensor_Add("strain2_midhoop", STRAIN2, Strain_Read, Strain_Init, Strain_Cleanup, Strain_Sanity);
  89         //Sensor_Add("strain3_midlong", STRAIN3, Strain_Read, Strain_Init, Strain_Cleanup, Strain_Sanity);
  90
  91         //Sensor_Add("microphone", 0, Microphone_Read, Microphone_Init, Microphone_Cleanup, Microphone_Sanity);
  92         //Sensor_Add("pressure0", PRESSURE0, Pressure_Read, Pressure_Init, 5000,0,5000,0);
  93         //Sensor_Add("pressure1", PRESSURE1, Pressure_Read, Pressure_Init, 5000,0,5000,0);
  94         //Sensor_Add("pressure_feedback", PRESSURE_FEEDBACK, Pressure_Read, Pressure_Init, 5000,0,5000,0);
  95         //Sensor_Add("enclosure", ENCLOSURE, Enclosure_Read, Enclosure_Init, 1,1,1,1); // Does not exist...
  96
  97         //NOTE: DO NOT ENABLE DILATOMETER WITHOUT FURTHER TESTING; CAUSES SEGFAULTS
  98         //Sensor_Add("dilatometer0", 0, Dilatometer_Read, Dilatometer_Init, Dilatometer_Cleanup, NULL);
  99         //Sensor_Add("dilatometer1",1, Dilatometer_Read, Dilatometer_Init, Dilatometer_Cleanup, NULL);
 100 }
 101
 102 /**
 103  * Cleanup all sensors
 104  */
 105 void Sensor_Cleanup()
 106 {
 107         for (int i = 0; i < g_num_sensors; ++i)
 108         {
 109                 Sensor * s = g_sensors+i;
 110                 if (s->cleanup != NULL)
 111                         s->cleanup(s->user_id);
 112         }
 113         g_num_sensors = 0;
 114 }
 115
 116 /**
 117  * Sets the sensor to the desired control mode. No checks are
 118  * done to see if setting to the desired mode will conflict with
 119  * the current mode - the caller must guarantee this itself.
 120  * @param s The sensor whose mode is to be changed
 121  * @param mode The mode to be changed to
 122  * @param arg An argument specific to the mode to be set.
 123  *            e.g for CONTROL_START it represents the experiment name.
 124  */
 125 void Sensor_SetMode(Sensor * s, ControlModes mode, void * arg)
 126 {
 127         switch(mode)
 128         {
 129                 case CONTROL_START:
 130                         {
 131                                 // Set filename
 132                                 char filename[BUFSIZ];
 133                                 const char *experiment_path = (const char*) arg;
 134                                 int ret;
 135
 136                                 ret = snprintf(filename, BUFSIZ, "%s/sensor_%d", experiment_path, s->id);
 137
 138                                 if (ret >= BUFSIZ)
 139                                 {
 140                                         Fatal("Experiment path \"%s\" too long (%d, limit %d)",
 141                                                         experiment_path, ret, BUFSIZ);
 142                                 }
 143
 144                                 Log(LOGDEBUG, "Sensor %d with DataFile \"%s\"", s->id, filename);
 145                                 // Open DataFile
 146                                 Data_Open(&(s->data_file), filename);
 147                         }
 148                 case CONTROL_RESUME: //Case fallthrough, no break before
 149                         {
 150                                 int ret;
 151                                 s->activated = true; // Don't forget this!
 152
 153                                 // Create the thread
 154                                 ret = pthread_create(&(s->thread), NULL, Sensor_Loop, (void*)(s));
 155                                 if (ret != 0)
 156                                 {
 157                                         Fatal("Failed to create Sensor_Loop for Sensor %d", s->id);
 158                                 }
 159
 160                                 Log(LOGDEBUG, "Resuming sensor %d", s->id);
 161                         }
 162                 break;
 163
 164                 case CONTROL_EMERGENCY:
 165                 case CONTROL_PAUSE:
 166                         s->activated = false;
 167                         pthread_join(s->thread, NULL);
 168                         Log(LOGDEBUG, "Paused sensor %d", s->id);
 169                 break;
 170
 171                 case CONTROL_STOP:
 172                         if (s->activated) //May have been paused before
 173                         {
 174                                 s->activated = false;
 175                                 pthread_join(s->thread, NULL);
 176                         }
 177
 178                         Data_Close(&(s->data_file)); // Close DataFile
 179                         Log(LOGDEBUG, "Stopped sensor %d", s->id);
 180                 break;
 181                 default:
 182                         Fatal("Unknown control mode: %d", mode);
 183         }
 184 }
 185
 186 /**
 187  * Sets all sensors to the desired mode.
 188  * @see Sensor_SetMode for more information.
 189  * @param mode The mode to be changed to
 190  * @param arg An argument specific to the mode to be set.
 191  */
 192 void Sensor_SetModeAll(ControlModes mode, void * arg)
 193 {
 194         if (mode == CONTROL_START)
 195                 Sensor_Init();
 196         for (int i = 0; i < g_num_sensors; i++)
 197                 Sensor_SetMode(&g_sensors[i], mode, arg);
 198         if (mode == CONTROL_STOP)
 199                 Sensor_Cleanup();
 200 }
 201
 202
 203 /**
 204  * Record data from a single Sensor; to be run in a seperate thread
 205  * @param arg - Cast to Sensor* - Sensor that the thread will handle
 206  * @returns NULL (void* required to use the function with pthreads)
 207  */
 208 void * Sensor_Loop(void * arg)
 209 {
 210         Sensor * s = (Sensor*)(arg);
 211         Log(LOGDEBUG, "Sensor %d starts", s->id);
 212
 213         // Until the sensor is stopped, record data points
 214         while (s->activated)
 215         {
 216
 217                 bool success = s->read(s->user_id, &(s->current_data.value));
 218
 219                 struct timespec t;
 220                 clock_gettime(CLOCK_MONOTONIC, &t);
 221                 s->current_data.time_stamp = TIMEVAL_DIFF(t, *Control_GetStartTime());
 222
 223                 if (success)
 224                 {
 225                         if (s->sanity != NULL)
 226                         {
 227                                 if (!s->sanity(s->user_id, s->current_data.value))
 228                                 {
 229                                         Fatal("Sensor %s (%d,%d) reads unsafe value", s->name, s->id, s->user_id);
 230                                 }
 231                         }
 232                         s->averaged_data.time_stamp += s->current_data.time_stamp;
 233                         s->averaged_data.value = s->current_data.value;
 234
 235                         if (++(s->num_read) >= s->averages)
 236                         {
 237                                 s->averaged_data.time_stamp /= s->averages;
 238                                 s->averaged_data.value /= s->averages;
 239                                 Data_Save(&(s->data_file), &(s->averaged_data), 1); // Record it
 240                                 s->num_read = 0;
 241                                 s->averaged_data.time_stamp = 0;
 242                                 s->averaged_data.value = 0;
 243                         }
 244                 }
 245                 else
 246                 {
 247                         // Silence because strain sensors fail ~50% of the time :S
 248                         //Log(LOGWARN, "Failed to read sensor %s (%d,%d)", s->name, s->id,s->user_id);
 249                 }
 250
 251
 252                 clock_nanosleep(CLOCK_MONOTONIC, 0, &(s->sample_time), NULL);
 253
 254         }
 255
 256         // Needed to keep pthreads happy
 257         Log(LOGDEBUG, "Sensor %s (%d,%d) finished", s->name,s->id,s->user_id);
 258         return NULL;
 259 }
 260
 261 /**
 262  * Get a Sensor given its name
 263  * @returns Sensor with the given name, NULL if there isn't one
 264  */
 265 Sensor * Sensor_Identify(const char * name)
 266 {
 267         for (int i = 0; i < g_num_sensors; ++i)
 268         {
 269                 if (strcmp(g_sensors[i].name, name) == 0)
 270                         return &(g_sensors[i]);
 271         }
 272         return NULL;
 273 }
 274
 275 /**
 276  * Helper: Begin sensor response in a given format
 277  * @param context - the FCGIContext
 278  * @param s - Sensor to begin the response for
 279  * @param format - Format
 280  */
 281 void Sensor_BeginResponse(FCGIContext * context, Sensor * s, DataFormat format)
 282 {
 283         // Begin response
 284         switch (format)
 285         {
 286                 case JSON:
 287                         FCGI_BeginJSON(context, STATUS_OK);
 288                         FCGI_JSONLong("id", s->id);
 289                         FCGI_JSONLong("user_id", s->user_id); //NOTE: Might not want to expose this?
 290                         FCGI_JSONPair("name", s->name);
 291                         break;
 292                 default:
 293                         FCGI_PrintRaw("Content-type: text/plain\r\n\r\n");
 294                         break;
 295         }
 296 }
 297
 298 /**
 299  * Helper: End sensor response in a given format
 300  * @param context - the FCGIContext
 301  * @param s - Sensor to end the response for
 302  * @param format - Format
 303  */
 304 void Sensor_EndResponse(FCGIContext * context, Sensor * s, DataFormat format)
 305 {
 306         // End response
 307         switch (format)
 308         {
 309                 case JSON:
 310                         FCGI_EndJSON();
 311                         break;
 312                 default:
 313                         break;
 314         }
 315 }
 316
 317 /**
 318  * Handle a request to the sensor module
 319  * @param context - The context to work in
 320  * @param params - Parameters passed
 321  */
 322 void Sensor_Handler(FCGIContext *context, char * params)
 323 {
 324         struct timespec now;
 325         clock_gettime(CLOCK_MONOTONIC, &now);
 326         double current_time = TIMEVAL_DIFF(now, *Control_GetStartTime());
 327         int id = 0;
 328         const char * name = "";
 329         double start_time = 0;
 330         double end_time = current_time;
 331         const char * fmt_str;
 332         double sample_s = 0;
 333
 334         // key/value pairs
 335         FCGIValue values[] = {
 336                 {"id", &id, FCGI_INT_T},
 337                 {"name", &name, FCGI_STRING_T},
 338                 {"format", &fmt_str, FCGI_STRING_T},
 339                 {"start_time", &start_time, FCGI_DOUBLE_T},
 340                 {"end_time", &end_time, FCGI_DOUBLE_T},
 341                 {"sample_s", &sample_s, FCGI_DOUBLE_T}
 342         };
 343
 344         // enum to avoid the use of magic numbers
 345         typedef enum {
 346                 ID,
 347                 NAME,
 348                 FORMAT,
 349                 START_TIME,
 350                 END_TIME,
 351                 SAMPLE_S
 352         } SensorParams;
 353
 354         // Fill values appropriately
 355         if (!FCGI_ParseRequest(context, params, values, sizeof(values)/sizeof(FCGIValue)))
 356         {
 357                 // Error occured; FCGI_RejectJSON already called
 358                 return;
 359         }
 360
 361         Sensor * s = NULL;
 362         if (FCGI_RECEIVED(values[NAME].flags))
 363         {
 364                 if (FCGI_RECEIVED(values[ID].flags))
 365                 {
 366                         FCGI_RejectJSON(context, "Can't supply both sensor id and name");
 367                         return;
 368                 }
 369                 s = Sensor_Identify(name);
 370                 if (s == NULL)
 371                 {
 372                         FCGI_RejectJSON(context, "Unknown sensor name");
 373                         return;
 374                 }
 375         }
 376         else if (!FCGI_RECEIVED(values[ID].flags))
 377         {
 378                 FCGI_RejectJSON(context, "No sensor id or name supplied");
 379                 return;
 380         }
 381         else if (id < 0 || id >= g_num_sensors)
 382         {
 383                 FCGI_RejectJSON(context, "Invalid sensor id");
 384                 return;
 385         }
 386         else
 387         {
 388                 s = &(g_sensors[id]);
 389         }
 390
 391         // Adjust sample rate if necessary
 392         if (FCGI_RECEIVED(values[SAMPLE_S].flags))
 393         {
 394                 if (sample_s < 0)
 395                 {
 396                         FCGI_RejectJSON(context, "Negative sampling speed!");
 397                         return;
 398                 }
 399                 DOUBLE_TO_TIMEVAL(sample_s, &(s->sample_time));
 400         }
 401
 402
 403         DataFormat format = Data_GetFormat(&(values[FORMAT]));
 404
 405         // Begin response
 406         Sensor_BeginResponse(context, s, format);
 407
 408         // Print Data
 409         Data_Handler(&(s->data_file), &(values[START_TIME]), &(values[END_TIME]), format, current_time);
 410
 411         // Finish response
 412         Sensor_EndResponse(context, s, format);
 413
 414 }
 415
 416 /**
 417  * Get the Name of a Sensor
 418  * @param id - ID number
 419  */
 420 const char * Sensor_GetName(int id)
 421 {
 422         return g_sensors[id].name;
 423 }
 424
 425 /**
 426  * Returns the last DataPoint that is currently available.
 427  * @param id - The sensor ID for which to retrieve data from
 428  * @return The last DataPoint
 429  */
 430 DataPoint Sensor_LastData(int id)
 431 {
 432         Sensor * s = &(g_sensors[id]);
 433         return s->current_data;
 434 }
 435
 436