4 files changed, 36 insertions, 1 deletions
diff --git a/gnuradio-runtime/include/gnuradio/block_detail.h b/gnuradio-runtime/include/gnuradio/block_detail.h
index 916c0a46c1..a71030b439 100644
--- a/gnuradio-runtime/include/gnuradio/block_detail.h
+++ b/gnuradio-runtime/include/gnuradio/block_detail.h
@@ -100,6 +100,13 @@ namespace gr {
     // Return the number of items written on output stream which_output
     uint64_t nitems_written(unsigned int which_output);
 
+    // sets nitems_read and nitems_written to 0 for all input/output
+    // buffers.
+    void reset_nitem_counters();
+
+    // Clears all tags from the input buffers.
+    void clear_tags();
+
     /*!
      * \brief  Adds a new tag to the given output stream.
      *
diff --git a/gnuradio-runtime/include/gnuradio/buffer.h b/gnuradio-runtime/include/gnuradio/buffer.h
index 5da383dc8f..914661b318 100644
--- a/gnuradio-runtime/include/gnuradio/buffer.h
+++ b/gnuradio-runtime/include/gnuradio/buffer.h
@@ -100,6 +100,8 @@ namespace gr {
 
     uint64_t nitems_written() { return d_abs_write_offset; }
 
+    void reset_nitem_counter() { d_abs_write_offset = 0; }
+
     size_t get_sizeof_item() { return d_sizeof_item; }
 
     /*!
@@ -288,6 +290,8 @@ namespace gr {
 
     uint64_t nitems_read() { return d_abs_read_offset; }
 
+    void reset_nitem_counter() { d_abs_read_offset = 0; }
+
     size_t get_sizeof_item() { return d_buffer->get_sizeof_item(); }
 
     /*!
diff --git a/gnuradio-runtime/lib/block_detail.cc b/gnuradio-runtime/lib/block_detail.cc
index 9463e8d13b..484d849652 100644
--- a/gnuradio-runtime/lib/block_detail.cc
+++ b/gnuradio-runtime/lib/block_detail.cc
@@ -162,6 +162,26 @@ namespace gr {
   }
 
   void
+  block_detail::reset_nitem_counters()
+  {
+    for(unsigned int i = 0; i < d_ninputs; i++) {
+      d_input[i]->reset_nitem_counter();
+    }
+    for(unsigned int o = 0; o < d_noutputs; o++) {
+      d_output[o]->reset_nitem_counter();
+    }
+  }
+
+  void
+  block_detail::clear_tags()
+  {
+    for(unsigned int i = 0; i < d_ninputs; i++) {
+      uint64_t max_time = 0xFFFFFFFFFFFFFFFF; // from now to the end of time
+      d_input[i]->buffer()->prune_tags(max_time);
+    }
+  }
+
+  void
   block_detail::add_item_tag(unsigned int which_output, const tag_t &tag)
   {
     if(!pmt::is_symbol(tag.key)) {
diff --git a/gnuradio-runtime/lib/flat_flowgraph.cc b/gnuradio-runtime/lib/flat_flowgraph.cc
index 81c1184cfa..653cfcc3d6 100644
--- a/gnuradio-runtime/lib/flat_flowgraph.cc
+++ b/gnuradio-runtime/lib/flat_flowgraph.cc
@@ -225,9 +225,10 @@ namespace gr {
           std::cout << "merge: allocating new detail for block " << (*p) << std::endl;
         block->set_detail(allocate_block_detail(block));
       }
-      else
+      else {
         if(FLAT_FLOWGRAPH_DEBUG)
           std::cout << "merge: reusing original detail for block " << (*p) << std::endl;
+      }
     }
 
     // Calculate the old edges that will be going away, and clear the
@@ -311,6 +312,9 @@ namespace gr {
       // Now deal with the fact that the block details might have
       // changed numbers of inputs and outputs vs. in the old
       // flowgraph.
+
+      block->detail()->reset_nitem_counters();
+      block->detail()->clear_tags();
     }
   }