rfnoc: graph: make topology failure more descriptive

Clarify that invalid RFNoC graph topology failures are due to an attempt
to access input or output ports that are not connected to anything in
the FPGA.

Signed-off-by: mattprost <matt.prost@ni.com>

1 files changed, 41 insertions, 4 deletions

diff --git a/host/lib/rfnoc/graph.cpp b/host/lib/rfnoc/graph.cpp
index 9b8b9ec59..897eade57 100644
--- a/host/lib/rfnoc/graph.cpp
+++ b/host/lib/rfnoc/graph.cpp
@@ -709,11 +709,48 @@ void graph_t::_check_topology()
         }
 
         if (!node_accessor.check_topology(node, connected_inputs, connected_outputs)) {
+            std::ostringstream input_topology;
+            input_topology << " requested inputs: (";
+            for (auto connected_input : connected_inputs) {
+                input_topology << connected_input;
+                if (connected_input != connected_inputs.back()) {
+                    input_topology << ", ";
+                }
+            }
+            input_topology << ")";
+            input_topology << " valid inputs: (";
+            for (size_t expected_input = 0; expected_input < node->get_num_input_ports();
+                 expected_input++) {
+                input_topology << expected_input;
+                if (expected_input < node->get_num_input_ports() - 1) {
+                    input_topology << ", ";
+                }
+            }
+            input_topology << ")";
+
+            std::ostringstream output_topology;
+            output_topology << " requested outputs: (";
+            for (auto connected_output : connected_outputs) {
+                output_topology << connected_output;
+                if (connected_output != connected_outputs.back()) {
+                    output_topology << ", ";
+                }
+            }
+            output_topology << ")";
+            output_topology << " valid outputs: (";
+            for (size_t expected_output = 0;
+                 expected_output < node->get_num_output_ports();
+                 expected_output++) {
+                output_topology << expected_output;
+                if (expected_output < node->get_num_output_ports() - 1) {
+                    output_topology << ", ";
+                }
+            }
+            output_topology << ")";
+
             UHD_LOG_ERROR(LOG_ID,
-                "Node " << node->get_unique_id()
-                        << "cannot handle its current topology! ("
-                        << connected_inputs.size() << "inputs, "
-                        << connected_outputs.size() << " outputs)");
+                "Node " << node->get_unique_id() << " using invalid inputs or outputs! "
+                        << input_topology.str() << ", " << output_topology.str());
             topo_ok = false;
         }
     }