2 files changed, 21 insertions, 0 deletions
diff --git a/lib/edi/STIDecoder.cpp b/lib/edi/STIDecoder.cpp
index d387f1e..2de828b 100644
--- a/lib/edi/STIDecoder.cpp
+++ b/lib/edi/STIDecoder.cpp
@@ -70,6 +70,12 @@ void STIDecoder::setMaxDelay(int num_af_packets)
     m_dispatcher.setMaxDelay(num_af_packets);
 }
 
+void STIDecoder::filter_stream_index(bool enable, uint16_t index)
+{
+    m_filter_stream = enable;
+    m_filtered_stream_index = index;
+}
+
 #define AFPACKET_HEADER_LEN 10 // includes SYNC
 
 bool STIDecoder::decode_starptr(const std::vector<uint8_t>& value, const tag_name_t& /*n*/)
@@ -173,6 +179,14 @@ bool STIDecoder::decode_ssn(const std::vector<uint8_t>& value, const tag_name_t&
     n = (uint16_t)(name[2]) << 8;
     n |= (uint16_t)(name[3]);
 
+    if (n == 0) {
+        etiLog.level(warn) << "EDI: Stream index SSnn tag is zero";
+    }
+
+    if (m_filter_stream and m_filtered_stream_index != n) {
+        return true;
+    }
+
     sti.stream_index = n - 1; // n is 1-indexed
     sti.rfa = value[0] >> 3;
     sti.tid = value[0] & 0x07;
diff --git a/lib/edi/STIDecoder.hpp b/lib/edi/STIDecoder.hpp
index f85f789..5e71ce7 100644
--- a/lib/edi/STIDecoder.hpp
+++ b/lib/edi/STIDecoder.hpp
@@ -119,6 +119,10 @@ class STIDecoder {
          */
         void setMaxDelay(int num_af_packets);
 
+        /* Enable/disable stream-index filtering.
+         * index==0 is out of spec, but some encoders do it anyway. */
+        void filter_stream_index(bool enable, uint16_t index);
+
     private:
         bool decode_starptr(const std::vector<uint8_t>& value, const tag_name_t& n);
         bool decode_dsti(const std::vector<uint8_t>& value, const tag_name_t& n);
@@ -132,6 +136,9 @@ class STIDecoder {
 
         STIDataCollector& m_data_collector;
         TagDispatcher m_dispatcher;
+
+        bool m_filter_stream = false;
+        uint16_t m_filtered_stream_index = 1;
 };
 
 }