Fix SensorHandler while loop

[matches/MCTX3420.git] / server / sensor.c

diff --git a/server/sensor.c b/server/sensor.c
index b746134..ab687af 100644 (file)
--- a/server/sensor.c
+++ b/server/sensor.c
@@ -64,12 +64,15 @@ void Sensor_Init(Sensor * s, int id)
        s->read_offset = 0;
        s->id = id;
 
-       #define FILENAMESIZE 4
+       #define FILENAMESIZE BUFSIZ
        char filename[FILENAMESIZE];
-       if (s->id >= pow(10, FILENAMESIZE))
+       //if (s->id >= pow(10, FILENAMESIZE))
+       if (false)
        {
                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
@@ -114,7 +117,7 @@ void * Sensor_Main(void * arg)
                        {
                                Fatal("Wrote %d data points and expected to write %d to \"%s\" - %s", amount_written, SENSOR_DATABUFSIZ, strerror(errno));
                        }
-                       Log(LOGDEBUG, "Wrote %d data points for sensor %d", amount_written, s->id);
+                       //Log(LOGDEBUG, "Wrote %d data points for sensor %d", amount_written, s->id);
                pthread_mutex_unlock(&(s->mutex));
                // End of critical section
 
@@ -124,4 +127,24 @@ void * Sensor_Main(void * arg)
        return NULL;
 }
 
+/**
+ * Fill buffer with most recent sensor data
+ * @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;
+}
+