gr-digital: update the HDLC blocks.

* HDLC deframer is now OVER 9000%! faster * No more correlate_access_code_tag req'd * Properly assign HDLC blocks to Packet Operators subgroup
author: Nick Foster <bistromath@gmail.com> 2014-05-07 16:41:51 -0700
committer: Johnathan Corgan <johnathan@corganlabs.com> 2014-05-09 13:52:29 -0700
commit: 5cd195341b0763b99b4e0462ee2387781bbf899d (patch)
tree: cdd9e409ea0cd5f88f19a1b2ca3f71e02beaa99c
parent: 8c97b7c379952c010c84cf8ae8a97fbfaac83bfd (diff)
6 files changed, 73 insertions, 100 deletions
diff --git a/gr-digital/grc/digital_hdlc_deframer_bp.xml b/gr-digital/grc/digital_hdlc_deframer_bp.xml
index 41bd37c7ee..3e78b891df 100644
--- a/gr-digital/grc/digital_hdlc_deframer_bp.xml
+++ b/gr-digital/grc/digital_hdlc_deframer_bp.xml
@@ -3,12 +3,7 @@
   <name>HDLC Deframer</name>
   <key>digital_hdlc_deframer_bp</key>
   <import>from gnuradio import digital</import>
-  <make>digital.hdlc_deframer_bp($frame_tag_name, $min, $max)</make>
-  <param>
-    <name>Frame tag name</name>
-    <key>frame_tag_name</key>
-    <type>string</type>
-  </param>
+  <make>digital.hdlc_deframer_bp($min, $max)</make>
   <param>
     <name>Min length</name>
     <key>min</key>
diff --git a/gr-digital/include/gnuradio/digital/hdlc_deframer_bp.h b/gr-digital/include/gnuradio/digital/hdlc_deframer_bp.h
index 191f294344..5a80670ddd 100644
--- a/gr-digital/include/gnuradio/digital/hdlc_deframer_bp.h
+++ b/gr-digital/include/gnuradio/digital/hdlc_deframer_bp.h
@@ -31,12 +31,9 @@ namespace gr {
 
     /*!
      * \brief HDLC deframer which takes in unpacked bits, and outputs PDU 
-     * binary blobs. This is intended for use with the 
-     * correlate_access_code_tag_bb block, which should have an access code
-     * of "01111110" for use with HDLC frames. Frames which do not pass CRC are
-     * rejected.
+     * binary blobs. Frames which do not pass CRC are rejected.
      *
-     * \ingroup digital
+     * \ingroup pkt_operators_blk
      *
      */
     class DIGITAL_API hdlc_deframer_bp : virtual public gr::sync_block
@@ -47,12 +44,10 @@ namespace gr {
       /*!
        * \brief Return a shared_ptr to a new instance of digital::hdlc_deframer.
        *
-       * \param frame_tag_name: The tag name from an upstream 
-       * correlate_access_code_tag_bb block.
        * \param length_min: Minimum frame size (default: 32)
        * \param length_max: Maximum frame size (default: 500)
        */
-      static sptr make(const std::string frame_tag_name, int length_min, int length_max);
+      static sptr make(int length_min, int length_max);
     };
 
   } // namespace digital
diff --git a/gr-digital/include/gnuradio/digital/hdlc_framer_pb.h b/gr-digital/include/gnuradio/digital/hdlc_framer_pb.h
index d2931a9fff..9f77f61540 100644
--- a/gr-digital/include/gnuradio/digital/hdlc_framer_pb.h
+++ b/gr-digital/include/gnuradio/digital/hdlc_framer_pb.h
@@ -42,7 +42,7 @@ namespace gr {
      * flowgraphs that stream continuously (anything using a USRP) this should
      * not be an issue.
      *
-     * \ingroup digital
+     * \ingroup pkt_operators_blk
      *
      */
     class DIGITAL_API hdlc_framer_pb : virtual public gr::sync_block
diff --git a/gr-digital/lib/hdlc_deframer_bp_impl.cc b/gr-digital/lib/hdlc_deframer_bp_impl.cc
index 69f0f8c00d..12d7ec66bc 100644
--- a/gr-digital/lib/hdlc_deframer_bp_impl.cc
+++ b/gr-digital/lib/hdlc_deframer_bp_impl.cc
@@ -32,29 +32,31 @@ namespace gr {
   namespace digital {
 
     hdlc_deframer_bp::sptr
-    hdlc_deframer_bp::make(const std::string frame_tag_name,
-                           int length_min=32,
+    hdlc_deframer_bp::make(int length_min=32,
                            int length_max=500)
     {
       return gnuradio::get_initial_sptr
-        (new hdlc_deframer_bp_impl(frame_tag_name, length_min, length_max));
+        (new hdlc_deframer_bp_impl(length_min, length_max));
     }
 
     /*
      * The private constructor
      */
-    hdlc_deframer_bp_impl::hdlc_deframer_bp_impl(const std::string frame_tag_name,
-                                                 int length_min,
+    hdlc_deframer_bp_impl::hdlc_deframer_bp_impl(int length_min,
                                                  int length_max)
       : gr::sync_block("hdlc_deframer_bp",
               gr::io_signature::make(1, 1, sizeof(unsigned char)),
               gr::io_signature::make(0, 0, 0)),
-        d_frame_tag_name(frame_tag_name),
         d_length_min(length_min),
         d_length_max(length_max)
     {
         set_output_multiple(length_max*2);
         message_port_register_out(pmt::mp("out"));
+        d_bytectr=0;
+        d_bitctr=0;
+        d_ones=0;
+        d_pktbuf = new unsigned char[length_max+2];
+        d_in_frame=false;
     }
 
     /*
@@ -64,39 +66,11 @@ namespace gr {
     {
     }
 
-    //undo HDLC bit stuffing operation.
-    static void unstuff(std::vector<unsigned char> &pkt) {
-        int consec = 0;
-        for(size_t i=0; i<pkt.size(); i++) {
-            if(pkt[i]) {
-                consec++;
-            } else {
-                if(consec == 5) {
-                    pkt.erase(pkt.begin()+i);
-                    i--;
-                }
-                consec = 0;
-            }
-        }
-    }
-
-    //pack unpacked (1 bit per byte) data into bytes, in reverse bit order
-    //we reverse the bit order because HDLC uses LSbit format.
-    std::vector<unsigned char>
-    hdlc_deframer_bp_impl::pack(std::vector<unsigned char> &data)
-    {
-        std::vector<unsigned char> output(std::ceil(data.size()/8.0f), 0);
-        for(size_t i=0; i<data.size(); i++) {
-            output[i/8] |= (data[i]<<(i%8));
-        }
-        return output;
-    }
-
     unsigned int
-    hdlc_deframer_bp_impl::crc_ccitt(std::vector<unsigned char> &data) {
+    hdlc_deframer_bp_impl::crc_ccitt(unsigned char *data, size_t len) {
         unsigned int POLY=0x8408; //reflected 0x1021
         unsigned short crc=0xFFFF;
-        for(size_t i=0; i<data.size(); i++) {
+        for(size_t i=0; i<len; i++) {
             crc ^= data[i];
             for(size_t j=0; j<8; j++) {
                 if(crc&0x01) crc = (crc >> 1) ^ POLY;
@@ -112,49 +86,55 @@ namespace gr {
                                 gr_vector_void_star &output_items)
     {
         const unsigned char *in = (const unsigned char *) input_items[0];
-
-        //look for frame delimiter tags
-        std::vector<gr::tag_t> frame_tags;
-        uint64_t abs_sample_cnt = nitems_read(0);
-        get_tags_in_range(frame_tags, 0, abs_sample_cnt, abs_sample_cnt + noutput_items, pmt::string_to_symbol(d_frame_tag_name));
-
-        int end_pos = 0;
-        while(frame_tags.size() > 0) {
-            int start_pos = frame_tags[0].offset - abs_sample_cnt;
-            if(frame_tags.size() == 1) return start_pos; //start here next time
-            end_pos   = frame_tags[1].offset - abs_sample_cnt;
-            int pkt_len   = frame_tags[1].offset - frame_tags[0].offset - 8; //omit EOF delim
-            if(pkt_len > d_length_max) return end_pos; //arbitrary, too long for a real pkt
-            if(pkt_len <= d_length_min)  return end_pos;
-
-            //get bit array
-            std::vector<unsigned char> pkt_bits(pkt_len);
-            memcpy(&pkt_bits[0], &in[start_pos], pkt_bits.size());
-
-            unstuff(pkt_bits);
-
-            //pack into bytes (and correct bit order)
-            std::vector<unsigned char> pkt_bytes = pack(pkt_bits);
-
-            //strip off the CRC
-            unsigned int crc = (int(pkt_bytes[pkt_bytes.size()-1]) << 8)
-                                    + pkt_bytes[pkt_bytes.size()-2];
-            pkt_bytes.erase(pkt_bytes.end()-2, pkt_bytes.end());
-            unsigned int calc_crc = crc_ccitt(pkt_bytes);
-
-            if(crc == calc_crc) {
-                //publish
-                //TODO manage padding
-                pmt::pmt_t pdu(pmt::cons(pmt::PMT_NIL,
-                                        pmt::make_blob(&pkt_bytes[0], pkt_bytes.size())));
-                message_port_pub(pmt::mp("out"), pdu);
+        unsigned char bit;
+        int n=0;
+        while (n < noutput_items) {
+            bit=*in;
+            if(d_ones>=5) {
+                if(bit) { //six ones is a frame delimiter
+                    if(d_bytectr >= d_length_min) {
+                        //check CRC, publish frame
+                        unsigned short crc = d_pktbuf[d_bytectr-1] << 8
+                                           | d_pktbuf[d_bytectr-2];
+                        unsigned short calc_crc = crc_ccitt(d_pktbuf, d_bytectr-2);
+                        if (crc==calc_crc) {
+                            pmt::pmt_t pdu(pmt::cons(pmt::PMT_NIL,
+                                                     pmt::make_blob(&d_pktbuf[0], d_bytectr-2)));
+                            message_port_pub(pmt::mp("out"), pdu);
+                        }
+                        else {
+                        }
+                        d_in_frame=false;
+                    } else {
+                        d_in_frame=true;
+                    }
+                    d_bitctr=0;
+                    d_bytectr=0;
+                } else { //unstuff
+                }
+            } else { //not 5+ continuous ones
+                if(d_in_frame) {
+                    if(d_bytectr > d_length_max) {
+                        d_bytectr=0;
+                        d_bitctr=0;
+                        d_in_frame=false;
+                    } else {
+                        d_pktbuf[d_bytectr]>>=1;
+                        if (bit) d_pktbuf[d_bytectr] |= 0x80;
+                        d_bitctr++;
+                        if (d_bitctr==8) {
+                            d_bitctr=0;
+                            d_bytectr++;
+                        }
+                    }
+                }
             }
-            frame_tags.erase(frame_tags.begin());
+            d_ones = (bit) ? d_ones+1 : 0;
+            in++;
+            n++;
         }
-        // Tell runtime system how many output items we produced.
-        return end_pos;
+        return n;
     }
-
   } /* namespace digital */
 } /* namespace gr */
 
diff --git a/gr-digital/lib/hdlc_deframer_bp_impl.h b/gr-digital/lib/hdlc_deframer_bp_impl.h
index de8f6b3db7..f7c4253b3d 100644
--- a/gr-digital/lib/hdlc_deframer_bp_impl.h
+++ b/gr-digital/lib/hdlc_deframer_bp_impl.h
@@ -31,14 +31,18 @@ namespace gr {
     class hdlc_deframer_bp_impl : public hdlc_deframer_bp
     {
      private:
-        std::string d_frame_tag_name;
-        int d_length_min;
-        int d_length_max;
-        unsigned int crc_ccitt(std::vector<unsigned char> &data);
-        std::vector<unsigned char> pack(std::vector<unsigned char> &pkt);
+        size_t d_length_min;
+        size_t d_length_max;
+        size_t d_ones;
+        size_t d_bytectr;
+        size_t d_bitctr;
+        bool d_in_frame;
+        unsigned char *d_pktbuf;
+
+        unsigned int crc_ccitt(unsigned char *data, size_t len);
 
      public:
-      hdlc_deframer_bp_impl(const std::string frame_tag_name, int length_min, int length_max);
+      hdlc_deframer_bp_impl(int length_min, int length_max);
       ~hdlc_deframer_bp_impl();
 
       // Where all the action really happens
diff --git a/gr-digital/python/digital/qa_hdlc_framer.py b/gr-digital/python/digital/qa_hdlc_framer.py
index f8d1923de1..6fed264546 100755
--- a/gr-digital/python/digital/qa_hdlc_framer.py
+++ b/gr-digital/python/digital/qa_hdlc_framer.py
@@ -39,10 +39,9 @@ class test_hdlc_framer(gr_unittest.TestCase):
         npkts = 20
         src_data = [0xFE, 0xDA, 0xAC, 0x29, 0x7F, 0xA2, 0x90, 0x0F, 0xF8]
         frame   = digital.hdlc_framer_pb("wat")
-        corr    = digital.correlate_access_code_tag_bb("01111110", 0, "frame")
-        deframe = digital.hdlc_deframer_bp("frame", 32, 500)
+        deframe = digital.hdlc_deframer_bp(8, 500)
         debug   = blocks.message_debug()
-        self.tb.connect(frame, corr, deframe)
+        self.tb.connect(frame, deframe)
         self.tb.msg_connect(deframe, "out", debug, "store")
         self.tb.start()
         msg = pmt.cons(pmt.PMT_NIL, pmt.init_u8vector(len(src_data),src_data))
author	Nick Foster <bistromath@gmail.com>	2014-05-07 16:41:51 -0700
committer	Johnathan Corgan <johnathan@corganlabs.com>	2014-05-09 13:52:29 -0700
commit	5cd195341b0763b99b4e0462ee2387781bbf899d (patch)
tree	cdd9e409ea0cd5f88f19a1b2ca3f71e02beaa99c
parent	8c97b7c379952c010c84cf8ae8a97fbfaac83bfd (diff)