Fix warnings in rftest executable

warning: ‘genericPowerPerAntena’ defined but not used [-Wunused-function]

    warning: ‘graph.text’ is used uninitialized [-Wuninitialized]

    warning: ignoring return value of ‘read’ declared with attribute ‘warn_unused_result’ [-Wunused-result]

openair1/PHY/TOOLS/calibration_scope.c

@@ -99,8 +99,9 @@ static void commonGraph(OAIgraph_t *graph, int type, FL_Coord x, FL_Coord y, FL_
 }
 
 static OAIgraph_t calibrationCommonGraph( void (*funct) (OAIgraph_t *graph, calibData_t *context),
-                                  int type, FL_Coord x, FL_Coord y, FL_Coord w, FL_Coord h, const char *label, FL_COLOR pointColor) {
-  OAIgraph_t graph;
+                                  int type, FL_Coord x, FL_Coord y, FL_Coord w, FL_Coord h, const char *label, FL_COLOR pointColor)
+{
+  OAIgraph_t graph = {0};
   commonGraph(&graph, type, x, y, w, h, label, pointColor);
   graph.funct=funct;
   return graph;
@@ -236,7 +237,9 @@ static void genericWaterFall (OAIgraph_t *graph, scopeSample_t *values, const in
   graph->iteration++;
 }
 
-static void genericPowerPerAntena(OAIgraph_t  *graph, const int nb_ant, const scopeSample_t **data, const int len) {
+__attribute__((unused))
+static void genericPowerPerAntena(OAIgraph_t  *graph, const int nb_ant, const scopeSample_t **data, const int len)
+{
   float *values, *time;
   oai_xygraph_getbuff(graph, &time, &values, len, 0);
 
@@ -263,7 +266,10 @@ static void gNBfreqWaterFall  (OAIgraph_t *graph, calibData_t *context) {
                    0, 0,
                    "X axis:one frame in time");
 }
-static void timeResponse (OAIgraph_t *graph, calibData_t *context) {
+
+__attribute__((unused))
+static void timeResponse (OAIgraph_t *graph, calibData_t *context)
+{
   #if 0
   const int len=2*phy_vars_gnb->frame_parms.ofdm_symbol_size;
   float *values, *time;

openair1/PHY/TOOLS/calibration_test.c

@@ -314,8 +314,13 @@ int main(int argc, char **argv) {
   rfdevice.trx_start_func(&rfdevice);
   
   while(!oai_exit) {
-    for (int i=0; i<antennas; i++)
-      read(fd, samplesTx[i], DFT*sizeof(c16_t));
+    for (int i=0; i<antennas; i++) {
+      ssize_t len = read(fd, samplesTx[i], DFT*sizeof(c16_t));
+      if (len < 0) {
+        fprintf(stderr, "error during read(): errno %d, %s\n", errno, strerror(errno));
+        exit(1);
+      }
+    }
     rfdevice.trx_read_func(&rfdevice, &timestamp, samplesRx, DFT, antennas);
     rfdevice.trx_write_func(&rfdevice, timestamp + TxAdvanceInDFTSize * DFT, samplesTx, DFT, antennas, 0);
   }