uhd: pulled in some worthwhile changes from flow control branch

1 files changed, 13 insertions, 3 deletions

diff --git a/host/lib/transport/vrt_packet_handler.hpp b/host/lib/transport/vrt_packet_handler.hpp
index 939517411..278bcfeaa 100644
--- a/host/lib/transport/vrt_packet_handler.hpp
+++ b/host/lib/transport/vrt_packet_handler.hpp
@@ -318,7 +318,7 @@ template <typename T> UHD_INLINE T get_context_code(
     ){
         //load the rest of the if_packet_info in here
         if_packet_info.num_payload_words32 = (num_samps*chans_per_otw_buff*otw_type.get_sample_size())/sizeof(boost::uint32_t);
-        if_packet_info.packet_count = state.next_packet_seq++;
+        if_packet_info.packet_count = state.next_packet_seq;
 
         //get send buffers for each channel
         managed_send_buffs_t send_buffs(buffs.size()/chans_per_otw_buff);
@@ -345,6 +345,7 @@ template <typename T> UHD_INLINE T get_context_code(
             size_t num_bytes_total = (vrt_header_offset_words32+if_packet_info.num_packet_words32)*sizeof(boost::uint32_t);
             send_buffs[i]->commit(num_bytes_total);
         }
+        state.next_packet_seq++; //increment sequence after commits
         return num_samps;
     }
 
@@ -387,10 +388,19 @@ template <typename T> UHD_INLINE T get_context_code(
             if_packet_info.sob = metadata.start_of_burst;
             if_packet_info.eob = metadata.end_of_burst;
 
+            //TODO remove this code when sample counts of zero are supported by hardware
+            std::vector<const void *> buffs_(buffs);
+            size_t total_num_samps_(total_num_samps);
+            if (total_num_samps == 0){
+                static const boost::uint64_t zeros = 0; //max size of a host sample
+                buffs_ = std::vector<const void *>(buffs.size(), &zeros);
+                total_num_samps_ = 1;
+            }
+
             return _send1(
                 state,
-                buffs, 0,
-                std::min(total_num_samps, max_samples_per_packet),
+                buffs_, 0,
+                std::min(total_num_samps_, max_samples_per_packet),
                 if_packet_info,
                 io_type, otw_type,
                 vrt_packer,