2 files changed, 30 insertions, 1 deletions
diff --git a/gnuradio-core/src/lib/runtime/gr_buffer.cc b/gnuradio-core/src/lib/runtime/gr_buffer.cc
index 1d67470ec..f6a0a98fb 100644
--- a/gnuradio-core/src/lib/runtime/gr_buffer.cc
+++ b/gnuradio-core/src/lib/runtime/gr_buffer.cc
@@ -156,8 +156,15 @@ gr_buffer::space_available ()
     // Find out the maximum amount of data available to our readers
 
     int	most_data = d_readers[0]->items_available ();
-    for (unsigned int i = 1; i < d_readers.size (); i++)
+    uint64_t min_items_read = d_readers[0]->nitems_read();
+    for (size_t i = 1; i < d_readers.size (); i++) {
       most_data = std::max (most_data, d_readers[i]->items_available ());
+      min_items_read = std::min(min_items_read, d_readers[i]->nitems_read());
+    }
+
+    for (size_t i = 0; i < d_readers.size (); i++) {
+      d_readers[i]->prune_tags(min_items_read);
+    }
 
     // The -1 ensures that the case d_write_index == d_read_index is
     // unambiguous.  It indicates that there is no data for the reader
@@ -287,6 +294,25 @@ gr_buffer_reader::get_tags_in_range(uint64_t abs_start,
   return found_items;
 }
 
+void
+gr_buffer_reader::prune_tags(uint64_t max_time)
+{
+  int n = 0;
+  uint64_t item_time;
+  std::deque<pmt::pmt_t>::iterator itr = d_buffer->get_tags_begin();
+
+  while(itr != d_buffer->get_tags_end()) {
+    item_time = pmt::pmt_to_uint64(pmt::pmt_tuple_ref(*itr, 0));
+    if(item_time < max_time) {
+      d_buffer->tags_pop_front();
+      n++;
+    }
+    else
+      break;
+    itr++;
+  }
+}
+
 long
 gr_buffer_reader_ncurrently_allocated ()
 {
diff --git a/gnuradio-core/src/lib/runtime/gr_buffer.h b/gnuradio-core/src/lib/runtime/gr_buffer.h
index d6d5564e8..47ba4cd96 100644
--- a/gnuradio-core/src/lib/runtime/gr_buffer.h
+++ b/gnuradio-core/src/lib/runtime/gr_buffer.h
@@ -101,6 +101,7 @@ class gr_buffer {
 
   std::deque<pmt::pmt_t>::iterator get_tags_begin() { return d_item_tags.begin(); }
   std::deque<pmt::pmt_t>::iterator get_tags_end() { return d_item_tags.end(); }
+  void tags_pop_front() { d_item_tags.pop_front(); }
 
   // -------------------------------------------------------------------------
 
@@ -260,6 +261,8 @@ class gr_buffer_reader {
   std::vector<pmt::pmt_t> get_tags_in_range(uint64_t abs_start,
 					    uint64_t abs_end);
 
+  void prune_tags(uint64_t max_time);
+
   // -------------------------------------------------------------------------
 
  private: