+++ /dev/null
-/**
- * @file sensor.c
- * @brief Implementation of sensor thread
- * TODO: Finalise implementation
- */
-
-#include "common.h"
-#include "sensor.h"
-#include "options.h"
-#include <math.h>
-
-/** Array of sensors, initialised by Sensor_Init **/
-static Sensor g_sensors[NUMSENSORS]; //global to this file
-const char * g_sensor_names[NUMSENSORS] = {
- "analog_test0", "analog_test1",
- "digital_test0", "digital_test1"
-};
-
-/**
- * Read a data value from a sensor; block until value is read
- * @param sensor_id - The ID of the sensor
- * @param d - DataPoint to set
- * @returns NULL for digital sensors when data is unchanged, otherwise d
- */
-DataPoint * GetData(SensorId sensor_id, DataPoint * d)
-{
- // switch based on the sensor_id at the moment for testing;
- // might be able to just directly access ADC from sensor_id?
- //TODO: Implement for real sensors
-
-
- //TODO: We should ensure the time is *never* allowed to change on the server if we use gettimeofday
- // Another way people might think of getting the time is to count CPU cycles with clock()
- // But this will not work because a) CPU clock speed may change on some devices (RPi?) and b) It counts cycles used by all threads
-
- struct timeval t;
- gettimeofday(&t, NULL);
- d->time_stamp = (t.tv_sec - g_options.start_time.tv_sec) + 1e-6*(t.tv_usec - g_options.start_time.tv_usec);
-
- // Make time relative
- //d->time_stamp.tv_sec -= g_options.start_time.tv_sec;
- //d->time_stamp.tv_usec -= g_options.start_time.tv_usec;
-
- switch (sensor_id)
- {
- case ANALOG_TEST0:
- {
- //CheckSensor( sensor_id, *sensor value*);
-
- static int count = 0;
- d->value = count++;
- break;
- }
- case ANALOG_TEST1:
- d->value = (double)(rand() % 100) / 100;
- break;
-
- //TODO: For digital sensors, consider only updating when sensor is actually changed
- case DIGITAL_TEST0:
- d->value = t.tv_sec % 2;
- break;
- case DIGITAL_TEST1:
- d->value = (t.tv_sec+1)%2;
- break;
- default:
- Fatal("Unknown sensor id: %d", sensor_id);
- break;
- }
- usleep(100000); // simulate delay in sensor polling
-
- return d;
-}
-
-/**
- * Checks the sensor data for unsafe or unexpected results
- * @param sensor_id - The ID of the sensor
- *
-*
-void CheckSensor( SensorId sensor_id)
-{
- switch (sensor_id)
- {
- case ANALOG_TEST0:
- {
- if( *sensor value* > ANALOG_TEST0_SAFETY)
- {
- LogEx(LOGERR, GetData, Sensor analog_test0 is above the safe value);
- //new log function that stops actuators?
- }
- //Also include a warning level?
- else if( *sensor value* > ANALOG_TEST0_WARN)
- {
- LogEx(LOGWARN, GetData, Sensor analog_test0);
- }
- }
- }
-
-
-*/
-
-
-/**
- * Destroy a sensor
- * @param s - Sensor to destroy
- */
-void Destroy(Sensor * s)
-{
- // Maybe move the binary file into long term file storage?
- fclose(s->file);
-}
-
-
-
-/**
- * Initialise a sensor
- * @param s - Sensor to initialise
- */
-void Init(Sensor * s, int id)
-{
- s->write_index = 0;
- s->id = id;
- s->points_written = 0;
- s->points_read = 0;
-
- #define FILENAMESIZE 3
- char filename[FILENAMESIZE];
- if (s->id >= pow(10, FILENAMESIZE))
- {
- Fatal("Too many sensors! FILENAMESIZE is %d; increase it and recompile.", FILENAMESIZE);
- }
-
- pthread_mutex_init(&(s->mutex), NULL);
-
- sprintf(filename, "%d", s->id);
- unlink(filename); //TODO: Move old files somewhere
-
- s->file = fopen(filename, "a+b"); // open binary file
- Log(LOGDEBUG, "Initialised sensor %d; binary file is \"%s\"", id, filename);
-}
-
-
-/**
- * Run the main sensor polling loop
- * @param arg - Cast to Sensor* - Sensor that the thread will handle
- * @returns NULL (void* required to use the function with pthreads)
- */
-void * Sensor_Main(void * arg)
-{
- Sensor * s = (Sensor*)(arg);
-
- while (Thread_Runstate() == RUNNING) //TODO: Exit condition
- {
- // The sensor will write data to a buffer until it is full
- // Then it will open a file and dump the buffer to the end of it.
- // Rinse and repeat
-
- // The reason I've added the buffer is because locks are expensive
- // But maybe it's better to just write data straight to the file
- // I'd like to do some tests by changing SENSOR_DATABUFSIZ
-
- while (s->write_index < SENSOR_DATABUFSIZ)
- {
- DataPoint * d = &(s->buffer[s->write_index]);
- if (GetData(s->id, d) == NULL)
- {
- Fatal("Error collecting data");
- }
- s->write_index += 1;
- }
-
- //Log(LOGDEBUG, "Filled buffer");
-
- // CRITICAL SECTION (no threads should be able to read/write the file at the same time)
- pthread_mutex_lock(&(s->mutex));
- //TODO: Valgrind complains about this fseek: "Syscall param write(buf) points to uninitialised byte(s)"
- // Not sure why, but we should find out and fix it.
- fseek(s->file, 0, SEEK_END);
- int amount_written = fwrite(s->buffer, sizeof(DataPoint), SENSOR_DATABUFSIZ, s->file);
- if (amount_written != SENSOR_DATABUFSIZ)
- {
- Fatal("Wrote %d data points and expected to write %d to \"%s\" - %s", amount_written, SENSOR_DATABUFSIZ, strerror(errno));
- }
- s->points_written += amount_written;
- //Log(LOGDEBUG, "Wrote %d data points for sensor %d", amount_written, s->id);
- pthread_mutex_unlock(&(s->mutex));
- // End of critical section
-
- s->write_index = 0; // reset position in buffer
-
- }
- Log(LOGDEBUG, "Thread for sensor %d exits", s->id);
- return NULL;
-}
-
-/**
- * Get position in a binary sensor file with a timestamp using a binary search
- * @param s - Sensor to use
- * @param time_stamp - Timestamp
- * @param count - If not NULL, used to provide number of searches required
- * @param found - If not NULL, set to the closest DataPoint
- * @returns Integer giving the *closest* index in the file
- * TODO: Refactor or replace?
- */
-int FindTime(Sensor * s, double time_stamp, int * count, DataPoint * found)
-{
- DataPoint d;
-
- int lower = 0;
- int upper = s->points_written - 1;
- int index = 0;
- if (count != NULL)
- *count = 0;
-
- while (upper - lower > 1)
- {
- index = lower + ((upper - lower)/2);
-
- // Basically anything with fseek is critical; if we don't make it critical the sensor thread may alter data at a random point in the file!
- // CRITICAL SECTION (May need to rethink how this is done, but I can't see how to do it without fseek :S)
- // Regarding the suggestion that we have 2 file pointers; one for reading and one for writing:
- // That seems like it will work... but we will have to be very careful and test it first
- pthread_mutex_lock(&s->mutex);
- fseek(s->file, index*sizeof(DataPoint), SEEK_SET);
- int amount_read = fread(&d, sizeof(DataPoint), 1, s->file);
- pthread_mutex_unlock(&s->mutex);
-
- if (amount_read != 1)
- {
- Fatal("Couldn't read single data point from sensor %d", s->id);
- }
-
- if (d.time_stamp > time_stamp)
- {
- upper = index;
- }
- else if (d.time_stamp < time_stamp)
- {
- lower = index;
- }
- if (count != NULL)
- *count += 1;
- }
-
- if (found != NULL)
- *found = d;
-
- return index;
-
-}
-
-/**
- * Print sensor data between two indexes in the file, using a given format
- * @param s - Sensor to use
- * @param start - Start index
- * @param end - End index
- * @param output_type - JSON, CSV or TSV output format
- */
-void PrintData(Sensor * s, int start, int end, OutputType output_type)
-{
- DataPoint buffer[SENSOR_QUERYBUFSIZ];
- int index = start;
-
- if (output_type == JSON)
- {
- FCGI_JSONValue("[");
- }
-
-
- while (index < end)
- {
- int to_read = end - index;
- if (to_read > SENSOR_QUERYBUFSIZ)
- {
- to_read = SENSOR_QUERYBUFSIZ;
- }
-
- int amount_read = 0;
- // CRITICAL SECTION
- pthread_mutex_lock(&(s->mutex));
-
- fseek(s->file, index*sizeof(DataPoint), SEEK_SET);
- amount_read = fread(buffer, sizeof(DataPoint), to_read, s->file);
-
- pthread_mutex_unlock(&(s->mutex));
- // End critical section
-
- if (amount_read != to_read)
- {
- Fatal("Failed to read %d DataPoints from sensor %d; read %d instead", to_read, s->id, amount_read);
- }
-
- // Print the data
- for (int i = 0; i < amount_read; ++i)
- {
- //TODO: Reformat?
- switch (output_type)
- {
- case JSON:
- FCGI_JSONValue("[%f, %f]", buffer[i].time_stamp, buffer[i].value);
- if (i+1 < amount_read)
- FCGI_JSONValue(",");
- break;
- case CSV:
- FCGI_PrintRaw("%f,%f\n", buffer[i].time_stamp, buffer[i].value);
- break;
- case TSV:
- default:
- FCGI_PrintRaw("%f\t%f\n", buffer[i].time_stamp, buffer[i].value);
- break;
- }
- }
- index += amount_read;
- }
-
- if (output_type == JSON)
- {
- FCGI_JSONValue("]");
- }
-}
-
-/**
- * Fill buffer with most recent sensor data
- * TODO: This may be obselete; remove?
- * @param s - Sensor to use
- * @param buffer - Buffer to fill
- * @param bufsiz - Size of buffer to fill
- * @returns The number of DataPoints actually read
- */
-int Sensor_Query(Sensor * s, DataPoint * buffer, int bufsiz)
-{
- int amount_read = 0;
- //CRITICAL SECTION (Don't access file while sensor thread is writing to it!)
- pthread_mutex_lock(&(s->mutex));
-
- fseek(s->file, -bufsiz*sizeof(DataPoint), SEEK_END);
- amount_read = fread(buffer, sizeof(DataPoint), bufsiz, s->file);
- //Log(LOGDEBUG, "Read %d data points", amount_read);
- pthread_mutex_unlock(&(s->mutex));
- return amount_read;
-}
-
-/**
- * Get a Sensor given an ID string
- * @param id_str ID string
- * @returns Sensor* identified by the string; NULL on error
- */
-Sensor * Sensor_Identify(const char * id_str)
-{
- char * end;
- // Parse string as integer
- int id = strtol(id_str, &end, 10);
- if (*end != '\0')
- {
- return NULL;
- }
- // Bounds check
- if (id < 0 || id >= NUMSENSORS)
- return NULL;
-
-
- Log(LOGDEBUG, "Sensor \"%s\" identified", g_sensor_names[id]);
- return g_sensors+id;
-}
-
-/**
- * Handle a request to the sensor module
- * @param context - The context to work in
- * @param params - Parameters passed
- * TODO: Seriously need to write more helper functions and decrease the size of this function!
- */
-void Sensor_Handler(FCGIContext *context, char * params)
-{
- StatusCodes status = STATUS_OK;
-
- OutputType output_type = JSON;
-
-
-
- const char * key; const char * value;
-
- Sensor * sensor = NULL;
-
- struct timeval now;
- gettimeofday(&now, NULL);
-
- double start_time = -1;
- double end_time = -1;
- double current_time = (now.tv_sec - g_options.start_time.tv_sec) + 1e-6*(now.tv_usec - g_options.start_time.tv_usec);
- bool seek_time = false;
- bool points_specified = false;
- int query_size = SENSOR_QUERYBUFSIZ;
- int start_index = -1;
- int end_index = -1;
-
-
- while ((params = FCGI_KeyPair(params, &key, &value)) != NULL)
- {
- Log(LOGDEBUG, "Got key=%s and value=%s", key, value);
- if (strcmp(key, "id") == 0)
- {
- if (sensor != NULL)
- {
- Log(LOGERR, "Only one sensor id should be specified");
- status = STATUS_ERROR;
- break;
- }
- if (*value == '\0')
- {
- Log(LOGERR, "No id specified.");
- status = STATUS_ERROR;
- break;
- }
-
- sensor = Sensor_Identify(value);
- if (sensor == NULL)
- {
- Log(LOGERR, "Invalid sensor id: %s", value);
- status = STATUS_ERROR;
- break;
- }
- }
- else if (strcmp(key, "format") == 0)
- {
- if (strcmp(value, "json") == 0)
- output_type = JSON;
- else if (strcmp(value, "csv") == 0)
- output_type = CSV;
- else if (strcmp(value, "tsv") == 0)
- output_type = TSV;
- }
- else if (strcmp(key, "points") == 0)
- {
- points_specified = true;
- if (strcmp(value, "all") == 0)
- {
- query_size = sensor->points_written;
- }
- else
- {
- char * end;
- query_size = strtol(value, &end, 10);
- if (*end != '\0')
- {
- Log(LOGERR, "Require \"all\" or an integer value: %s = %s", key, value);
- status = STATUS_ERROR;
- break;
- }
- }
-
- }
- else if (strcmp(key, "start_time") == 0)
- {
- seek_time = true;
- char * end;
- start_time = strtod(value, &end);
- if (*end != '\0')
- {
- Log(LOGERR, "Require a double: %s = %s", key, value);
- status = STATUS_ERROR;
- break;
- }
-
- // Treat negative values as being relative to the current time
- if (start_time < 0)
- {
- start_time = current_time + start_time;
- }
- start_time = floor(start_time);
- }
- else if (strcmp(key, "end_time") == 0)
- {
- seek_time = true;
- char * end;
- end_time = strtod(value, &end);
- if (*end != '\0')
- {
- Log(LOGERR, "Require a double: %s = %s", key, value);
- status = STATUS_ERROR;
- break;
- }
-
- // Treat negative values as being relative to the current time
- if (end_time < 0)
- {
- end_time = current_time + end_time;
- }
- end_time = ceil(end_time);
- }
- // For backward compatability:
- else if (strcmp(key, "dump") == 0)
- {
- output_type = TSV;
- query_size = sensor->points_written+1;
- }
- else
- {
- Log(LOGERR, "Unknown key \"%s\" (value = %s)", key, value);
- status = STATUS_ERROR;
- break;
- }
- }
-
- if (status != STATUS_ERROR && sensor == NULL)
- {
- Log(LOGERR, "No valid sensor id given");
- status = STATUS_ERROR;
- }
-
- if (status == STATUS_ERROR)
- {
- FCGI_RejectJSON(context, "Invalid input parameters");
- return;
- }
-
-
- if (seek_time)
- {
- if (end_time < 0 && !points_specified)
- end_index = sensor->points_written;
- else
- {
- int count = 0; DataPoint d;
- end_index = FindTime(sensor, end_time, &count, &d);
- Log(LOGDEBUG, "FindTime - Looked for %f; found [%f,%f] after %d iterations; sensor %d, position %d", end_time, d.time_stamp, d.value, count, sensor->id, end_index);
- }
- if (start_time < 0)
- start_time = 0;
- else
- {
- int count = 0; DataPoint d;
- start_index = FindTime(sensor, start_time, &count, &d);
- Log(LOGDEBUG, "FindTime - Looked for %f; found [%f,%f] after %d iterations; sensor %d, position %d", start_time, d.time_stamp, d.value, count, sensor->id, start_index);
- }
-
- if (points_specified)
- end_index = start_index + query_size;
- }
- else
- {
- start_index = sensor->points_written - query_size;
-
- end_index = sensor->points_written;
- }
-
- if (start_index < 0)
- {
- Log(LOGNOTE, "start_index = %d => Clamped to 0", start_index);
- start_index = 0;
- }
- if (end_index > sensor->points_written)
- {
- Log(LOGNOTE, "end_index = %d => Clamped to %d", end_index, sensor->points_written);
- end_index = sensor->points_written;
- }
-
- switch (output_type)
- {
- case JSON:
- FCGI_BeginJSON(context, status);
- FCGI_JSONLong("id", sensor->id);
- FCGI_JSONKey("data");
- PrintData(sensor, start_index, end_index, output_type);
- FCGI_EndJSON();
- break;
- default:
- FCGI_PrintRaw("Content-type: text/plain\r\n\r\n");
- PrintData(sensor, start_index, end_index, output_type);
- //Force download with content-disposition
- // Sam: This is cool, but I don't think we should do it
- // - letting the user view it in the browser and then save with their own filename is more flexible
- //"Content-disposition: attachment;filename=%d.csv\r\n\r\n", sensor->id);
- break;
- }
-
-}
-
-/**
- * Setup Sensors, start Sensor polling thread(s)
- */
-void Sensor_Spawn()
-{
- // start sensor threads
- for (int i = 0; i < NUMSENSORS; ++i)
- {
- Init(g_sensors+i, i);
- pthread_create(&(g_sensors[i].thread), NULL, Sensor_Main, (void*)(g_sensors+i));
- }
-}
-
-/**
- * Quit Sensor loops
- */
-void Sensor_Join()
-{
- if (!Thread_Runstate())
- {
- Fatal("This function should not be called before Thread_QuitProgram");
- }
- for (int i = 0; i < NUMSENSORS; ++i)
- {
- pthread_join(g_sensors[i].thread, NULL);
- Destroy(g_sensors+i);
- }
-}