Correcting filtering of options and handling of option groups

Workflow options have to be handled independently from option groups to make sure that
all arguments are forwarded. In case of using an option group for a processor, the
filtering function is called with only a subset from the command line arguments, and
aplying this to the workflow options resulted in forwarding of the default arguments
instead of the arguments from the command line.

Author: matthiasrichter

Framework/Core/src/DeviceSpecHelpers.cxx

@@ -562,6 +562,7 @@ void DeviceSpecHelpers::prepareArguments(int argc, char** argv, bool defaultQuie
                                          std::vector<DeviceExecution>& deviceExecutions,
                                          std::vector<DeviceControl>& deviceControls)
 {
+  assert(argc > 0); // we require to have the program name as the first argument
   assert(deviceSpecs.size() == deviceExecutions.size());
   assert(deviceControls.size() == deviceExecutions.size());
   for (size_t si = 0; si < deviceSpecs.size(); ++si) {
@@ -591,19 +592,23 @@ void DeviceSpecHelpers::prepareArguments(int argc, char** argv, bool defaultQuie
     std::vector<std::string> tmpArgs = { argv[0],       "--id",  spec.id.c_str(), "--control", "static",
                                          "--log-color", "false", "--color",       "false" };
 
-    // do the filtering of options, forward options belonging to this specific
-    // DeviceSpec, and some global options from getForwardedDeviceOptions
+    // do the filtering of options:
+    // 1) forward options belonging to this specific DeviceSpec
+    // 2) global options defined in getForwardedDeviceOptions and workflow option are
+    //    always forwarded and need to be handled separately
     const char* name = spec.name.c_str();
-    bpo::options_description od;
-    bpo::options_description wo;
+    bpo::options_description od;     // option descriptions per process
+    bpo::options_description foDesc; // forwarded options for all processes
     ConfigParamsHelper::prepareOptionsDescription(spec.options, od);
-    ConfigParamsHelper::prepareOptionsDescription(workflowOptions, wo);
-    od.add(getForwardedDeviceOptions());
-    od.add(wo);
     od.add_options()(name, bpo::value<std::string>());
+    ConfigParamsHelper::prepareOptionsDescription(workflowOptions, foDesc);
+    foDesc.add(getForwardedDeviceOptions());
 
     using FilterFunctionT = std::function<void(decltype(argc), decltype(argv), decltype(od))>;
 
+    // the filter function will forward command line arguments based on the option
+    // definition passed to it. All options of the program option definition will be forwarded
+    // if found in the argument list. If not found they will be added with the default value
     FilterFunctionT filterArgsFct = [&](int largc, char** largv, const bpo::options_description& odesc) {
       // spec contains options
       bpo::command_line_parser parser{ largc, largv };
@@ -667,6 +672,9 @@ void DeviceSpecHelpers::prepareArguments(int argc, char** argv, bool defaultQuie
       }
     };
 
+    // filter global options and workflow options independent of option groups
+    filterArgsFct(argc, argv, foDesc);
+    // filter device options, and handle option groups
     filterArgsFct(argc, argv, od);
 
     // Add the channel configuration
@@ -697,7 +705,7 @@ void DeviceSpecHelpers::prepareArguments(int argc, char** argv, bool defaultQuie
   }
 }
 
-/// define the options which are forwarded to the FairMQ device
+/// define the options which are forwarded to every child
 boost::program_options::options_description DeviceSpecHelpers::getForwardedDeviceOptions()
 {
   // - rate is an option of FairMQ device for ConditionalRun