digital: made the tagging description for packet header gen more explicit

author: Martin Braun <martin.braun@kit.edu> 2013-03-29 19:06:48 +0100
committer: Martin Braun <martin.braun@kit.edu> 2013-03-29 19:06:48 +0100
commit: a67bfcc5fcbea9064a05cfdd4bea7b6fab2c531f (patch)
tree: a7f4ef4ae3e2eccbc6b400a0329d52594aeecb44 /gr-digital
parent: b7a5f16fcd559b8246a9155c6602a6b539be039e (diff)
6 files changed, 49 insertions, 29 deletions
diff --git a/gr-digital/include/digital/packet_headergenerator_bb.h b/gr-digital/include/digital/packet_headergenerator_bb.h
index 8d92bf84e..cec860fd5 100644
--- a/gr-digital/include/digital/packet_headergenerator_bb.h
+++ b/gr-digital/include/digital/packet_headergenerator_bb.h
@@ -33,18 +33,33 @@ namespace gr {
      * \brief Generates a header for a tagged, streamed packet.
      * \ingroup digital
      *
-     * Input: A tagged stream. The first element must have a tag with the key
-     *        specified in len_tag_key, which hold the exact number of elements
-     *        in the PDU.
-     * Output: An tagged stream of length header_len. The output is determined
-     *         by a header formatter.
+     * Input: A tagged stream. This is consumed entirely, it is not appended
+     *        to the output stream.
+     * Output: An tagged stream containing the header. The details on the header
+     *         are set in a header formatter object (of type packet_header_default
+     *         or a subclass thereof). If only a number of bits is specified, a
+     *         default header is generated (see packet_header_default).
      */
     class DIGITAL_API packet_headergenerator_bb : virtual public gr_tagged_stream_block
     {
      public:
       typedef boost::shared_ptr<packet_headergenerator_bb> sptr;
 
-      static sptr make(const packet_header_default::sptr &header_formatter);
+      /* \param header_formatter A header formatter object.
+       * \param len_tag_key Length tag key. Note that for header generation,
+       *                    it is irrelevant which tag names are set in the
+       *                    formatter object, only this value is relevant!
+       */
+      static sptr make(
+	  const packet_header_default::sptr &header_formatter,
+	  const std::string &len_tag_key="packet_len"
+      );
+
+      /* \param header_len If this value is given, a packet_header_default
+       *                   object is used to generate the header. This is
+       *                   the number of bits per header.
+       * \param len_tag_key Length tag key.
+       */
       static sptr make(
 	   long header_len,
 	   const std::string &len_tag_key = "packet_len");
diff --git a/gr-digital/include/digital/packet_headerparser_b.h b/gr-digital/include/digital/packet_headerparser_b.h
index a3db069cb..2dc6a8071 100644
--- a/gr-digital/include/digital/packet_headerparser_b.h
+++ b/gr-digital/include/digital/packet_headerparser_b.h
@@ -35,7 +35,11 @@ namespace gr {
      *
      * In a sense, this is the inverse block to packet_headergenerator_bb.
      * The difference is, the parsed header is not output as a stream,
-     * but as a message.
+     * but as a PMT dictionary, which is published to message port with
+     * the id "header_data".
+     * The dictionary consists of the tags created by the header formatter
+     * object. You should be able to use the exact same formatter object
+     * as used on the Tx side in the packet_headergenerator_bb.
      *
      * If only a header length is given, this block uses the default header
      * format.
diff --git a/gr-digital/lib/packet_headergenerator_bb_impl.cc b/gr-digital/lib/packet_headergenerator_bb_impl.cc
index 269897772..431849e05 100644
--- a/gr-digital/lib/packet_headergenerator_bb_impl.cc
+++ b/gr-digital/lib/packet_headergenerator_bb_impl.cc
@@ -30,9 +30,12 @@ namespace gr {
   namespace digital {
 
     packet_headergenerator_bb::sptr
-    packet_headergenerator_bb::make(const packet_header_default::sptr &header_formatter)
+    packet_headergenerator_bb::make(
+	const packet_header_default::sptr &header_formatter,
+	const std::string &len_tag_key
+    )
     {
-      return gnuradio::get_initial_sptr (new packet_headergenerator_bb_impl(header_formatter));
+      return gnuradio::get_initial_sptr (new packet_headergenerator_bb_impl(header_formatter, len_tag_key));
     }
 
 
@@ -45,25 +48,23 @@ namespace gr {
       const packet_header_default::sptr header_formatter(
 	  new packet_header_default(header_len, len_tag_key)
       );
-      return gnuradio::get_initial_sptr (new packet_headergenerator_bb_impl(header_formatter));
+      return gnuradio::get_initial_sptr (new packet_headergenerator_bb_impl(header_formatter, len_tag_key));
     }
 
 
     packet_headergenerator_bb_impl::packet_headergenerator_bb_impl(
-		    const gr::digital::packet_header_default::sptr &header_formatter
+		    const gr::digital::packet_header_default::sptr &header_formatter,
+		    const std::string &len_tag_key
 		    )
       : gr_tagged_stream_block("packet_headergenerator_bb_impl",
 		       gr_make_io_signature(1, 1, sizeof (char)),
 		       gr_make_io_signature(1, 1, sizeof (char)),
-		       pmt::pmt_symbol_to_string(header_formatter->len_tag_key())),
-	    d_formatter(header_formatter),
-	    d_input_size(1),
-	    d_header_len(header_formatter->header_len()),
-	    d_len_tag_value(pmt::pmt_from_long(d_header_len))
+		       len_tag_key),
+	    d_formatter(header_formatter)
     {
-      set_output_multiple(d_header_len);
+      set_output_multiple(d_formatter->header_len());
       // This is the worst case rate, because we don't know the true value, of course
-      set_relative_rate(d_header_len);
+      set_relative_rate(d_formatter->header_len());
       set_tag_propagation_policy(TPP_DONT);
     }
 
@@ -82,7 +83,7 @@ namespace gr {
 	throw std::runtime_error("header formatter returned false.");
       }
 
-      return d_header_len;
+      return d_formatter->header_len();
     }
 
   } /* namespace digital */
diff --git a/gr-digital/lib/packet_headergenerator_bb_impl.h b/gr-digital/lib/packet_headergenerator_bb_impl.h
index 7d2494cf8..ce60fdf76 100644
--- a/gr-digital/lib/packet_headergenerator_bb_impl.h
+++ b/gr-digital/lib/packet_headergenerator_bb_impl.h
@@ -31,16 +31,16 @@ namespace gr {
     {
      private:
       gr::digital::packet_header_default::sptr d_formatter;
-      int d_input_size;
-      int d_header_len;
-      pmt::pmt_t d_len_tag_value;
 
      public:
-      packet_headergenerator_bb_impl(const packet_header_default::sptr &header_formatter);
+      packet_headergenerator_bb_impl(
+	  const packet_header_default::sptr &header_formatter,
+	  const std::string &len_tag_key
+      );
       ~packet_headergenerator_bb_impl();
 
       void remove_length_tags(const std::vector<std::vector<gr_tag_t> > &tags) {};
-      int calculate_output_stream_length(const gr_vector_int &ninput_items) { return d_header_len; };
+      int calculate_output_stream_length(const gr_vector_int &ninput_items) { return d_formatter->header_len(); };
 
       int work(int noutput_items,
 	  gr_vector_int &ninput_items,
diff --git a/gr-digital/python/ofdm_txrx.py b/gr-digital/python/ofdm_txrx.py
index 2734e9cc1..de9811a64 100644
--- a/gr-digital/python/ofdm_txrx.py
+++ b/gr-digital/python/ofdm_txrx.py
@@ -128,10 +128,10 @@ class ofdm_tx(gr.hier_block2):
             total_sync_word = sync_word1 + sync_word2
         crc = digital.crc32_bb(False, self.frame_length_tag_key)
         formatter_object = digital.packet_header_ofdm(
-            occupied_carriers, 1, "", "", "",
-            bps_header
+            occupied_carriers=occupied_carriers, n_syms=1,
+            bits_per_sym=self.bps_header
         )
-        header_gen = digital.packet_headergenerator_bb(formatter_object.base())
+        header_gen = digital.packet_headergenerator_bb(formatter_object.base(), self.frame_length_tag_key)
         header_payload_mux = blocks.tagged_stream_mux(gr.sizeof_gr_complex*1, self.frame_length_tag_key)
         self.connect(self, crc, header_gen, header_mod, (header_payload_mux, 0))
         payload_constellation = _get_constellation(bps_payload)
diff --git a/gr-digital/python/qa_packet_headergenerator_bb.py b/gr-digital/python/qa_packet_headergenerator_bb.py
index 1aeaa8606..11f6ebfe7 100755
--- a/gr-digital/python/qa_packet_headergenerator_bb.py
+++ b/gr-digital/python/qa_packet_headergenerator_bb.py
@@ -109,7 +109,7 @@ class qa_packet_headergenerator_bb (gr_unittest.TestCase):
         tag3.value = pmt.pmt_from_long(4)
         src = gr.vector_source_b(data, False, 1, (tag1, tag2, tag3))
         formatter_object = digital.packet_header_default(12, tagname)
-        header = digital.packet_headergenerator_bb(formatter_object.formatter())
+        header = digital.packet_headergenerator_bb(formatter_object.formatter(), tagname)
         sink = gr.vector_sink_b()
         self.tb.connect(src, header, sink)
         self.tb.run()
@@ -141,7 +141,7 @@ class qa_packet_headergenerator_bb (gr_unittest.TestCase):
         formatter_object = digital.packet_header_ofdm(occupied_carriers, 1, tagname)
         self.assertEqual(formatter_object.header_len(), 6)
         self.assertEqual(pmt.pmt_symbol_to_string(formatter_object.len_tag_key()), tagname)
-        header = digital.packet_headergenerator_bb(formatter_object.formatter())
+        header = digital.packet_headergenerator_bb(formatter_object.formatter(), tagname)
         sink = gr.vector_sink_b()
         self.tb.connect(src, header, sink)
         self.tb.run()
author	Martin Braun <martin.braun@kit.edu>	2013-03-29 19:06:48 +0100
committer	Martin Braun <martin.braun@kit.edu>	2013-03-29 19:06:48 +0100
commit	a67bfcc5fcbea9064a05cfdd4bea7b6fab2c531f (patch)
tree	a7f4ef4ae3e2eccbc6b400a0329d52594aeecb44 /gr-digital
parent	b7a5f16fcd559b8246a9155c6602a6b539be039e (diff)