2 files changed, 41 insertions, 0 deletions
diff --git a/gnuradio-runtime/lib/hier_block2_detail.cc b/gnuradio-runtime/lib/hier_block2_detail.cc
index 60910d0dd9..0d0ddf55ba 100644
--- a/gnuradio-runtime/lib/hier_block2_detail.cc
+++ b/gnuradio-runtime/lib/hier_block2_detail.cc
@@ -328,11 +328,45 @@ namespace gr {
   }
 
   void
+  hier_block2_detail::refresh_io_signature()
+  {
+    int min_inputs  = d_owner->input_signature()->min_streams();
+    int max_inputs  = d_owner->input_signature()->max_streams();
+    int min_outputs = d_owner->output_signature()->min_streams();
+    int max_outputs = d_owner->output_signature()->max_streams();
+
+    if(max_inputs == io_signature::IO_INFINITE ||
+       max_outputs == io_signature::IO_INFINITE ||
+       (min_inputs != max_inputs) ||(min_outputs != max_outputs) ) {
+      std::stringstream msg;
+      msg << "Hierarchical blocks do not yet support arbitrary or"
+        << " variable numbers of inputs or outputs (" << d_owner->name() << ")";
+      throw std::runtime_error(msg.str());
+    }
+
+    // Check for # input change
+    if ((signed)d_inputs.size() != max_inputs)
+    {
+      d_inputs.resize(max_inputs);
+    }
+
+    // Check for # output change
+    if ((signed)d_outputs.size() != max_outputs)
+    {
+      d_outputs.resize(max_outputs);
+      d_min_output_buffer.resize(max_outputs, 0);
+      d_max_output_buffer.resize(max_outputs, 0);
+    }
+  }
+
+  void
   hier_block2_detail::connect_input(int my_port, int port,
                                     basic_block_sptr block)
   {
     std::stringstream msg;
 
+    refresh_io_signature();
+
     if(my_port < 0 || my_port >= (signed)d_inputs.size()) {
       msg << "input port " << my_port << " out of range for " << block;
       throw std::invalid_argument(msg.str());
@@ -356,6 +390,8 @@ namespace gr {
   {
     std::stringstream msg;
 
+    refresh_io_signature();
+
     if(my_port < 0 || my_port >= (signed)d_outputs.size()) {
       msg << "output port " << my_port << " out of range for " << block;
       throw std::invalid_argument(msg.str());
@@ -376,6 +412,8 @@ namespace gr {
   {
     std::stringstream msg;
 
+    refresh_io_signature();
+
     if(my_port < 0 || my_port >= (signed)d_inputs.size()) {
       msg << "input port number " << my_port << " out of range for " << block;
       throw std::invalid_argument(msg.str());
@@ -399,6 +437,8 @@ namespace gr {
   {
     std::stringstream msg;
 
+    refresh_io_signature();
+
     if(my_port < 0 || my_port >= (signed)d_outputs.size()) {
       msg << "output port number " << my_port << " out of range for " << block;
       throw std::invalid_argument(msg.str());
diff --git a/gnuradio-runtime/lib/hier_block2_detail.h b/gnuradio-runtime/lib/hier_block2_detail.h
index 8c38c3754a..a5584fe92a 100644
--- a/gnuradio-runtime/lib/hier_block2_detail.h
+++ b/gnuradio-runtime/lib/hier_block2_detail.h
@@ -71,6 +71,7 @@ namespace gr {
     endpoint_vector_t d_outputs;             // Single internal endpoint per external output
     basic_block_vector_t d_blocks;
 
+    void refresh_io_signature();
     void connect_input(int my_port, int port, basic_block_sptr block);
     void connect_output(int my_port, int port, basic_block_sptr block);
     void disconnect_input(int my_port, int port, basic_block_sptr block);