--- /dev/null
+/**
+ * @file data.c
+ * @purpose Implementation of data handling functions; saving, loading, displaying, selecting.
+ */
+
+#include "data.h"
+#include <assert.h> //TODO: Remove asserts
+
+/**
+ * One off initialisation of DataFile
+ * @param df - The DataFile
+ */
+void Data_Init(DataFile * df)
+{
+ // Everything is NULL
+ df->filename = NULL;
+ df->read_file = NULL;
+ df->write_file = NULL;
+}
+
+/**
+ * Initialise a DataFile from a filename; opens read/write FILE*
+ * @param df - DataFile to initialise
+ * @param filename - Name of file; overwritten if it exists
+ */
+void Data_Open(DataFile * df, const char * filename)
+{
+ assert(filename != NULL);
+ assert(df != NULL);
+
+ // Set the filename
+ df->filename = strdup(filename);
+
+ // Set number of DataPoints
+ df->num_points = 0;
+
+ // Set write FILE*
+ df->write_file = fopen(filename, "w+");
+ if (df->write_file == NULL)
+ {
+ Fatal("Error opening DataFile %s - %s", filename, strerror(errno));
+ }
+
+ // Set read FILE*
+ df->read_file = df->write_file;
+
+ //NOTE: Opening the same file in read mode gives funny results; fread generally reads less than expected
+ // The strerror is: "Transport endpoint is not connected"
+ /*
+ fopen(filename, "r");
+ if (df->read_file == NULL)
+ {
+ Fatal("Error opening DataFile %s - %s", filename, strerror(errno));
+ }
+ */
+
+}
+
+/**
+ * Close a DataFile
+ * @param df - The DataFile to close
+ */
+void Data_Close(DataFile * df)
+{
+ assert(df != NULL);
+
+ //TODO: Write data to TSV?
+
+ // Clear the FILE*s
+ df->read_file = NULL;
+ df->write_file = NULL;
+
+ fclose(df->write_file);
+
+ // Clear the filename
+ free(df->filename);
+ df->filename = NULL;
+}
+
+/**
+ * Save DataPoints to a DataFile
+ * @param df - The DataFile to save to
+ * @param buffer - Array of DataPoint(s) to save
+ * @param amount - Number of DataPoints in the buffer
+ */
+void Data_Save(DataFile * df, DataPoint * buffer, int amount)
+{
+ pthread_mutex_unlock(&(df->mutex));
+ assert(df != NULL);
+ assert(buffer != NULL);
+ assert(amount >= 0);
+
+ // Go to the end of the file
+ if (fseek(df->write_file, 0, SEEK_END) < 0)
+ {
+ Fatal("Error seeking to end of DataFile %s - %s", df->filename, strerror(errno));
+ }
+
+ // Attempt to write the DataPoints
+ int amount_written = fwrite(buffer, sizeof(DataPoint), amount, df->write_file);
+
+ // Check if the correct number of points were written
+ if (amount_written != amount)
+ {
+ Fatal("Wrote %d points instead of %d to DataFile %s - %s", amount_written, amount, df->filename, strerror(errno));
+ }
+
+ // Update number of DataPoints
+ df->num_points += amount_written;
+
+ pthread_mutex_unlock(&(df->mutex));
+
+}
+
+/**
+ * Read DataPoints from a DataFile
+ * @param df - The DataFile to read from
+ * @param buffer - Array to fill with DataPoints
+ * @param index - Index to start reading at (inclusive)
+ * @param amount - Maximum number of DataPoints to read
+ * @returns - Actual number of points read (If smaller than amount, the end of the file was reached)
+ */
+int Data_Read(DataFile * df, DataPoint * buffer, int index, int amount)
+{
+ pthread_mutex_lock(&(df->mutex));
+
+ assert(df != NULL);
+ assert(buffer != NULL);
+ assert(index >= 0);
+ assert(amount > 0);
+
+ // If we would read past the end of the file, reduce the amount of points to read
+
+ if (index + amount > df->num_points)
+ {
+ Log(LOGDEBUG, "Requested %d points but will only read %d to get to EOF (%d)", amount, df->num_points - index, df->num_points);
+ amount = df->num_points - index;
+ }
+
+
+ // Go to position in file
+ if (fseek(df->read_file, index*sizeof(DataPoint), SEEK_SET))
+ {
+ Fatal("Error seeking to position %d in DataFile %s - %s", index, df->filename, strerror(errno));
+ }
+
+ // Attempt to read the DataPoints
+ int amount_read = fread(buffer, sizeof(DataPoint), amount, df->read_file);
+
+ // Check if correct number of points were read
+ if (amount_read != amount)
+ {
+ Log(LOGERR,"Read %d points instead of %d from DataFile %s - %s", amount_read, amount, df->filename, strerror(errno));
+ }
+
+ pthread_mutex_unlock(&(df->mutex));
+ return amount_read;
+}
+
+/**
+ * Print data points between two indexes using a given format
+ * @param df - DataFile to print
+ * @param start_index - Index to start at (inclusive)
+ * @param end_index - Index to end at (inclusive)
+ * @param format - The format to use
+ */
+void Data_PrintByIndexes(DataFile * df, int start_index, int end_index, DataFormat format)
+{
+ assert(df != NULL);
+ assert(start_index >= 0);
+ assert(end_index >= 0);
+ assert(end_index <= df->num_points-1 || df->num_points == 0);
+
+ const char * fmt_string; // Format for each data point
+ char seperator; // Character used to seperate successive data points
+
+ // Determine what format string and seperator character to use
+ switch (format)
+ {
+ case JSON:
+ fmt_string = "[%f,%f]";
+ seperator = ',';
+ // For JSON we need an opening bracket
+ FCGI_PrintRaw("[");
+ break;
+ case TSV:
+ fmt_string = "%f\t%f";
+ seperator = '\n';
+ break;
+ }
+
+ DataPoint buffer[DATA_BUFSIZ]; // Buffer
+ // initialise buffer to stop stuff complaining
+ memset(buffer, 0, sizeof(DataPoint)*DATA_BUFSIZ);
+
+ if (start_index < end_index)
+ {
+
+ int index = start_index;
+ // Repeat until all DataPoints are printed
+ while (index <= end_index)
+ {
+ // Fill the buffer from the DataFile
+ int amount_read = Data_Read(df, buffer, index, DATA_BUFSIZ);
+
+ // Print all points in the buffer
+ for (int i = 0; i < amount_read && index <= end_index; ++i)
+ {
+ // Print individual DataPoint
+ FCGI_PrintRaw(fmt_string, buffer[i].time_stamp, buffer[i].value);
+
+ // Last seperator is not required
+ if (index+1 <= end_index)
+ FCGI_PrintRaw("%c", seperator);
+
+ // Advance the position in the DataFile
+ ++index;
+ }
+ }
+ }
+
+ switch (format)
+ {
+ case JSON:
+ // For JSON we need a closing bracket
+ FCGI_PrintRaw("]");
+ break;
+ default:
+ break;
+ }
+}
+
+/**
+ * Print data points between two time stamps using a given format.
+ * Prints nothing if the time stamp
+ * @param df - DataFile to print
+ * @param start_time - Time to start from (inclusive)
+ * @param end_time - Time to end at (inclusive)
+ * @param format - The format to use
+ */
+void Data_PrintByTimes(DataFile * df, double start_time, double end_time, DataFormat format)
+{
+ assert(df != NULL);
+ assert(start_time >= 0);
+ assert(end_time >= 0);
+ assert(end_time >= start_time);
+
+ DataPoint closest;
+
+ // Get starting index
+ int start_index = Data_FindByTime(df, start_time, &closest);
+
+ // Start time is greater than most recent time stamp
+ if (start_index >= df->num_points-1)
+ {
+ if (start_index == 0 || closest.time_stamp < start_time)
+ {
+ Data_PrintByIndexes(df, 0, 0, format); // Will print "empty" dataset
+ return;
+ }
+ }
+
+ // Get finishing index
+ int end_index = Data_FindByTime(df, end_time, &closest);
+
+ // Print data between the indexes
+ Data_PrintByIndexes(df, start_index, end_index, format);
+}
+
+/**
+ * Get the index of the DataPoint closest to a given time stamp
+ * @param df - DataFile to search
+ * @param time_stamp - The time stamp to search for
+ * @param closest - If not NULL, will be filled with the DataPoint chosen
+ * @returns index of DataPoint with the *closest* time stamp to that given
+ */
+int Data_FindByTime(DataFile * df, double time_stamp, DataPoint * closest)
+{
+ assert(df != NULL);
+ assert(time_stamp >= 0);
+ assert(closest != NULL);
+
+ DataPoint tmp; // Current DataPoint in binary search
+
+ int lower = 0; // lower index in binary search
+ pthread_mutex_lock(&(df->mutex));
+ int upper = df->num_points - 1; // upper index in binary search
+ pthread_mutex_unlock(&(df->mutex));
+ int index = 0; // current index in binary search
+
+ // Commence binary search:
+ while (upper - lower > 1)
+ {
+ // Pick midpoint
+ index = lower + ((upper - lower)/2);
+
+ // Look at DataPoint
+ if (Data_Read(df, &tmp, index, 1) != 1)
+ {
+ Fatal("Couldn't read DataFile %s at index %d", df->filename, index);
+ }
+
+ // Change search interval to either half appropriately
+ if (tmp.time_stamp > time_stamp)
+ {
+ upper = index;
+ }
+ else if (tmp.time_stamp < time_stamp)
+ {
+ lower = index;
+ }
+ }
+
+ // Store closest DataPoint
+ if (closest != NULL)
+ *closest = tmp;
+
+ return index;
+
+}
/** Array of sensors, initialised by Sensor_Init **/
static Sensor g_sensors[NUMSENSORS]; //global to this file
+
+/** Human readable names for the sensors **/
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
+ * One off initialisation of *all* sensors
*/
-DataPoint * GetData(SensorId sensor_id, DataPoint * d)
+void Sensor_Init()
{
- // 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
+ for (int i = 0; i < NUMSENSORS; ++i)
+ {
+ g_sensors[i].id = i;
+ Data_Init(&(g_sensors[i].data_file));
+ g_sensors[i].record_data = false;
+ }
+}
+/**
+ * Start a Sensor recording DataPoints
+ * @param s - The Sensor to start
+ * @param experiment_name - Prepended to DataFile filename
+ */
+void Sensor_Start(Sensor * s, const char * experiment_name)
+{
+ // Set filename
+ char filename[BUFSIZ];
+ if (sprintf(filename, "%s_%d", experiment_name, s->id) >= BUFSIZ)
+ {
+ Fatal("Experiment name \"%s\" too long (>%d)", experiment_name, BUFSIZ);
+ }
+
+ Log(LOGDEBUG, "Sensor %d with DataFile \"%s\"", s->id, filename);
+ // Open DataFile
+ Data_Open(&(s->data_file), filename);
+
+ s->record_data = true; // Don't forget this!
+
+ // Create the thread
+ pthread_create(&(s->thread), NULL, Sensor_Loop, (void*)(s));
+}
+
+/**
+ * Stop a Sensor from recording DataPoints. Blocks until it has stopped.
+ * @param s - The Sensor to stop
+ */
+void Sensor_Stop(Sensor * s)
+{
+ // Stop
+ if (s->record_data)
+ {
+ s->record_data = false;
+ pthread_join(s->thread, NULL); // Wait for thread to exit
+ Data_Close(&(s->data_file)); // Close DataFile
+ s->newest_data.time_stamp = 0;
+ s->newest_data.value = 0;
+ }
+}
+
+/**
+ * Stop all Sensors
+ */
+void Sensor_StopAll()
+{
+ for (int i = 0; i < NUMSENSORS; ++i)
+ Sensor_Stop(g_sensors+i);
+}
+
+/**
+ * Start all Sensors
+ */
+void Sensor_StartAll(const char * experiment_name)
+{
+ for (int i = 0; i < NUMSENSORS; ++i)
+ Sensor_Start(g_sensors+i, experiment_name);
+}
+
+/**
+ * Read a DataPoint from a Sensor; block until value is read
+ * @param id - The ID of the sensor
+ * @param d - DataPoint to set
+ * @returns True if the DataPoint was different from the most recently recorded.
+ */
+bool Sensor_Read(Sensor * s, DataPoint * d)
+{
- //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
-
+ // Set time stamp
struct timeval t;
gettimeofday(&t, NULL);
d->time_stamp = TIMEVAL_DIFF(t, g_options.start_time);
- // 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)
+ // Read value based on Sensor Id
+ switch (s->id)
{
case ANALOG_TEST0:
+ d->value = (double)(rand() % 100) / 100;
+ break;
+
+ case ANALOG_TEST1:
{
- //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;
d->value = (t.tv_sec+1)%2;
break;
default:
- Fatal("Unknown sensor id: %d", sensor_id);
+ Fatal("Unknown sensor id: %d", s->id);
break;
}
usleep(100000); // simulate delay in sensor polling
- return d;
+ // Perform sanity check based on Sensor's ID and the DataPoint
+ Sensor_CheckData(s->id, d);
+
+ // Update latest DataPoint if necessary
+ bool result = (d->value != s->newest_data.value);
+ if (result)
+ {
+ s->newest_data.time_stamp = d->time_stamp;
+ s->newest_data.value = d->value;
+ }
+ return result;
}
/**
* Checks the sensor data for unsafe or unexpected results
* @param sensor_id - The ID of the sensor
- *
-*
-void CheckSensor( SensorId sensor_id)
+ * @param d - DataPoint to check
+ */
+void Sensor_CheckData(SensorId id, DataPoint * d)
{
+ //TODO: Implement
+ /*
switch (sensor_id)
{
case 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
+ * Record data from a single Sensor; to be run in a seperate thread
* @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)
+void * Sensor_Loop(void * arg)
{
Sensor * s = (Sensor*)(arg);
+ Log(LOGDEBUG, "Sensor %d starts", s->id);
- while (Thread_Runstate() == RUNNING) //TODO: Exit condition
+ // Until the sensor is stopped, record data points
+ while (s->record_data)
{
- // 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;
+ //Log(LOGDEBUG, "Sensor %d reads data [%f,%f]", s->id, d.time_stamp, d.value);
+ if (Sensor_Read(s, &d)) // If new DataPoint is read:
{
- DataPoint * d = &(s->buffer[s->write_index]);
- if (GetData(s->id, d) == NULL)
- {
- Fatal("Error collecting data");
- }
- s->write_index += 1;
+ //Log(LOGDEBUG, "Sensor %d saves data [%f,%f]", s->id, d.time_stamp, d.value);
+ Data_Save(&(s->data_file), &d, 1); // Record it
}
-
- //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("[");
- }
+ // Needed to keep pthreads happy
-
- 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;
+ Log(LOGDEBUG, "Sensor %d finished", s->id);
+ return NULL;
}
/**
return g_sensors+id;
}
+/**
+ * Helper: Begin sensor response in a given format
+ * @param context - the FCGIContext
+ * @param format - Format
+ * @param id - ID of sensor
+ */
+void Sensor_BeginResponse(FCGIContext * context, SensorId id, DataFormat format)
+{
+ // Begin response
+ switch (format)
+ {
+ case JSON:
+ FCGI_BeginJSON(context, STATUS_OK);
+ FCGI_JSONLong("id", id);
+ FCGI_JSONKey("data");
+ break;
+ default:
+ FCGI_PrintRaw("Content-type: text/plain\r\n\r\n");
+ break;
+ }
+}
+
+/**
+ * Helper: End sensor response in a given format
+ * @param context - the FCGIContext
+ * @param id - ID of the sensor
+ * @param format - Format
+ */
+void Sensor_EndResponse(FCGIContext * context, SensorId id, DataFormat format)
+{
+ // End response
+ switch (format)
+ {
+ case JSON:
+ FCGI_EndJSON();
+ break;
+ default:
+ break;
+ }
+}
+
/**
* 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 = TIMEVAL_DIFF(now, g_options.start_time)
- bool seek_time = false;
- bool points_specified = false;
- int query_size = SENSOR_QUERYBUFSIZ;
- int start_index = -1;
- int end_index = -1;
-
- /* //Possible use case?
- FCGIValue values[5] = {
- {"id", &id, FCGI_REQUIRED(FCGI_INT_T)},
- {"format", &format, FCGI_STRING_T},
- {"points", &points, FCGI_STRING_T},
- {"start_time", &start_time, FCGI_DOUBLE_T},
- {"end_time", &end_time, FCGI_DOUBLE_T}
+ double current_time = TIMEVAL_DIFF(now, g_options.start_time);
+
+ int id = 0;
+ double start_time = 0;
+ double end_time = current_time;
+ char * fmt_str;
+
+ // key/value pairs
+ FCGIValue values[] = {
+ {"id", &id, FCGI_REQUIRED(FCGI_LONG_T)},
+ {"format", &fmt_str, FCGI_STRING_T},
+ {"start_time", &start_time, FCGI_DOUBLE_T},
+ {"end_time", &end_time, FCGI_DOUBLE_T},
};
- if (!FCGI_ParseRequest(context, params, values, 5))
- return;*/
-
- 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)
+ // enum to avoid the use of magic numbers
+ typedef enum {
+ ID,
+ FORMAT,
+ START_TIME,
+ END_TIME,
+ } SensorParams;
+
+ // Fill values appropriately
+ if (!FCGI_ParseRequest(context, params, values, sizeof(values)/sizeof(FCGIValue)))
{
- FCGI_RejectJSON(context, "Invalid input parameters");
+ // Error occured; FCGI_RejectJSON already called
return;
}
+ // Get Sensor
+ Sensor * s = NULL;
- if (seek_time)
+ // Error checking on sensor id
+ if (id < 0 || id >= NUMSENSORS)
{
- 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;
+ Log(LOGERR, "Invalid id %d", id);
}
else
{
- start_index = sensor->points_written - query_size;
-
- end_index = sensor->points_written;
+ s = g_sensors+id;
}
- if (start_index < 0)
- {
- Log(LOGNOTE, "start_index = %d => Clamped to 0", start_index);
- start_index = 0;
- }
- if (end_index > sensor->points_written)
+ DataFormat format = JSON;
+
+ // Check if format type was specified
+ if (FCGI_RECEIVED(values[FORMAT].flags))
{
- Log(LOGNOTE, "end_index = %d => Clamped to %d", end_index, sensor->points_written);
- end_index = sensor->points_written;
+ if (strcmp(fmt_str, "json") == 0)
+ format = JSON;
+ else if (strcmp(fmt_str, "tsv") == 0)
+ format = TSV;
+ else
+ Log(LOGERR, "Unknown format type \"%s\"", fmt_str);
}
+
- 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)
+ // Begin response
+ Sensor_BeginResponse(context, id, format);
+
+ // If a time was specified
+ if ((s != NULL) && (FCGI_RECEIVED(values[START_TIME].flags) || FCGI_RECEIVED(values[END_TIME].flags)))
{
- Init(g_sensors+i, i);
- pthread_create(&(g_sensors[i].thread), NULL, Sensor_Main, (void*)(g_sensors+i));
- }
-}
+ // Wrap times relative to the current time
+ if (start_time < 0)
+ start_time += current_time;
+ if (end_time < 0)
+ end_time += current_time;
+
+ // Print points by time range
+ Data_PrintByTimes(&(s->data_file), start_time, end_time, format);
-/**
- * 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)
+ else if (s != NULL) // No time was specified; just return a recent set of points
{
- pthread_join(g_sensors[i].thread, NULL);
- Destroy(g_sensors+i);
+ pthread_mutex_lock(&(s->data_file.mutex));
+ int start_index = s->data_file.num_points-DATA_BUFSIZ;
+ int end_index = s->data_file.num_points-1;
+ pthread_mutex_unlock(&(s->data_file.mutex));
+
+ // Bounds check
+ if (start_index < 0)
+ start_index = 0;
+ if (end_index < 0)
+ end_index = 0;
+
+ // Print points by indexes
+ Log(LOGDEBUG, "Sensor %d file \"%s\" indexes %d->%d", s->id, s->data_file.filename, start_index, end_index);
+ Data_PrintByIndexes(&(s->data_file), start_index, end_index, format);
}
+
+ // Finish response
+ Sensor_EndResponse(context, id, format);
+
}
+
+