COB-57: Use -p for parset, add -h, check for -p as it is mandatory

RTCP/Cobalt/InputProc/src/Station/generate.cc

@@ -41,10 +41,10 @@ using namespace std;
 
 void usage()
 {
-  cerr << "Usage: generator [options]" << endl;
+  cerr << "Usage: generator -p parset [options]" << endl;
   cerr << endl;
-  cerr << "-P parset       Read configuration from given (augmented) parset." << endl;
-  exit(1);
+  cerr << "-h              Show this help." << endl;
+  cerr << "-p parset       Read configuration from given (augmented) parset." << endl;
 }
 
 int main( int argc, char **argv )
@@ -55,12 +55,16 @@ int main( int argc, char **argv )
   string parsetFilename;
 
   // parse all command-line options
-  while ((opt = getopt(argc, argv, "P:")) != -1) {
+  while ((opt = getopt(argc, argv, "hp:")) != -1) {
     switch (opt) {
-    case 'P':
+    case 'p':
       parsetFilename = optarg;
       break;
 
+    case 'h':
+      usage();
+      exit(0);
+
     default: /* '?' */
       usage();
       exit(1);
@@ -73,6 +77,12 @@ int main( int argc, char **argv )
     exit(1);
   }
 
+  // check for mandatory parameters
+  if (parsetFilename == "") {
+    usage();
+    exit(1);
+  }
+
   LOFAR::Cobalt::MPI mpi;
   mpi.init(argc, argv);
   LOG_INFO_STR("MPI rank " << mpi.rank() << " out of " << mpi.size() << " hosts");