Merge branch 'correlate_tag'

5 files changed, 278 insertions, 3 deletions

diff --git a/gnuradio-core/src/lib/general/Makefile.am b/gnuradio-core/src/lib/general/Makefile.am
index 2a7a4b025..15272dd5c 100644
--- a/gnuradio-core/src/lib/general/Makefile.am
+++ b/gnuradio-core/src/lib/general/Makefile.am
@@ -181,7 +181,8 @@ libgeneral_la_SOURCES = 		\
 	gr_probe_density_b.cc		\
 	gr_annotator_alltoall.cc	\
 	gr_annotator_1to1.cc		\
-	gr_burst_tagger.cc
+	gr_burst_tagger.cc \
+	gr_correlate_access_code_tag_bb.cc
 
 libgeneral_qa_la_SOURCES = 		\
 	qa_general.cc			\
@@ -355,7 +356,8 @@ grinclude_HEADERS = 			\
 	gr_probe_density_b.h		\
 	gr_annotator_alltoall.h		\
 	gr_annotator_1to1.h		\
-	gr_burst_tagger.h
+	gr_burst_tagger.h	\
+	gr_correlate_access_code_tag_bb.h
 
 noinst_HEADERS = 			\
 	qa_general.h			\
@@ -499,4 +501,5 @@ swiginclude_HEADERS =			\
 	gr_probe_density_b.i		\
 	gr_annotator_alltoall.i		\
 	gr_annotator_1to1.i		\
-	gr_burst_tagger.i
+	gr_burst_tagger.i	\
+	gr_correlate_access_code_tag_bb.i
diff --git a/gnuradio-core/src/lib/general/general.i b/gnuradio-core/src/lib/general/general.i
index e8a18ab19..fd158cd1f 100644
--- a/gnuradio-core/src/lib/general/general.i
+++ b/gnuradio-core/src/lib/general/general.i
@@ -146,6 +146,7 @@
 #include <gr_annotator_alltoall.h>
 #include <gr_annotator_1to1.h>
 #include <gr_burst_tagger.h>
+#include <gr_correlate_access_code_tag_bb.h>
 %}
 
 %include "gr_nop.i"
@@ -272,3 +273,4 @@
 %include "gr_annotator_alltoall.i"
 %include "gr_annotator_1to1.i"
 %include "gr_burst_tagger.i"
+%include "gr_correlate_access_code_tag_bb.i"
diff --git a/gnuradio-core/src/lib/general/gr_correlate_access_code_tag_bb.cc b/gnuradio-core/src/lib/general/gr_correlate_access_code_tag_bb.cc
new file mode 100644
index 000000000..23311f7a4
--- /dev/null
+++ b/gnuradio-core/src/lib/general/gr_correlate_access_code_tag_bb.cc
@@ -0,0 +1,129 @@
+/* -*- c++ -*- */
+/*
+ * Copyright 2004,2006,2010,2011 Free Software Foundation, Inc.
+ * 
+ * This file is part of GNU Radio
+ * 
+ * GNU Radio is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 3, or (at your option)
+ * any later version.
+ * 
+ * GNU Radio is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with GNU Radio; see the file COPYING.  If not, write to
+ * the Free Software Foundation, Inc., 51 Franklin Street,
+ * Boston, MA 02110-1301, USA.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <gr_correlate_access_code_tag_bb.h>
+#include <gr_io_signature.h>
+#include <stdexcept>
+#include <gr_count_bits.h>
+#include <cstdio>
+#include <iostream>
+
+#define VERBOSE 0
+
+
+gr_correlate_access_code_tag_bb_sptr
+gr_make_correlate_access_code_tag_bb (const std::string &access_code, int threshold, const std::string &tag_name)
+{
+  return gnuradio::get_initial_sptr(new gr_correlate_access_code_tag_bb (access_code, threshold, tag_name));
+}
+
+
+gr_correlate_access_code_tag_bb::gr_correlate_access_code_tag_bb (
+  const std::string &access_code, int threshold, const std::string &tag_name)
+  : gr_sync_block ("correlate_access_code_tag_bb",
+		   gr_make_io_signature (1, 1, sizeof(char)),
+		   gr_make_io_signature (1, 1, sizeof(char))),
+    d_data_reg(0), d_mask(0), d_len(0),
+    d_threshold(threshold)
+
+{
+  if (!set_access_code(access_code)){
+    fprintf(stderr, "gr_correlate_access_code_tag_bb: access_code is > 64 bits\n");
+    throw std::out_of_range ("access_code is > 64 bits");
+  }
+
+  std::stringstream str;
+  str << name() << unique_id();
+  d_me = pmt::pmt_string_to_symbol(str.str());
+  d_key = pmt::pmt_string_to_symbol(tag_name);
+}
+
+gr_correlate_access_code_tag_bb::~gr_correlate_access_code_tag_bb ()
+{
+}
+
+bool
+gr_correlate_access_code_tag_bb::set_access_code(
+  const std::string &access_code)
+{
+  d_len = access_code.length();	// # of bytes in string
+  if (d_len > 64)
+    return false;
+
+  // set len top bits to 1.
+  d_mask = ((~0ULL) >> (64 - d_len)) << (64 - d_len);
+
+  d_access_code = 0;
+  for (unsigned i=0; i < 64; i++){
+    d_access_code <<= 1;
+    if (i < d_len)
+      d_access_code |= access_code[i] & 1;	// look at LSB only
+  }
+
+  return true;
+}
+
+int
+gr_correlate_access_code_tag_bb::work (int noutput_items,
+				   gr_vector_const_void_star &input_items,
+				   gr_vector_void_star &output_items)
+{
+  const unsigned char *in = (const unsigned char *) input_items[0];
+  unsigned char *out = (unsigned char *) output_items[0];
+
+  uint64_t abs_out_sample_cnt = nitems_written(0);
+
+  for (int i = 0; i < noutput_items; i++){
+
+    out[i] = in[i];
+    
+    // compute hamming distance between desired access code and current data
+    unsigned long long wrong_bits = 0;
+    unsigned int nwrong = d_threshold+1;
+    int new_flag = 0;
+
+    wrong_bits  = (d_data_reg ^ d_access_code) & d_mask;
+    nwrong = gr_count_bits64(wrong_bits);
+
+    // test for access code with up to threshold errors
+    new_flag = (nwrong <= d_threshold);
+
+    // shift in new data and new flag
+    d_data_reg = (d_data_reg << 1) | (in[i] & 0x1);
+    if (new_flag) {
+      if(VERBOSE) std::cout << "writing tag at sample " << abs_out_sample_cnt + i << std::endl;
+      add_item_tag(0, //stream ID
+	    abs_out_sample_cnt + i - 64 + d_len, //sample
+	    d_key,      //frame info
+	    pmt::pmt_t(), //data (unused)
+        d_me        //block src id
+      );
+    }
+  }
+
+  return noutput_items;
+}
+  
diff --git a/gnuradio-core/src/lib/general/gr_correlate_access_code_tag_bb.h b/gnuradio-core/src/lib/general/gr_correlate_access_code_tag_bb.h
new file mode 100644
index 000000000..06dd4ca02
--- /dev/null
+++ b/gnuradio-core/src/lib/general/gr_correlate_access_code_tag_bb.h
@@ -0,0 +1,81 @@
+/* -*- c++ -*- */
+/*
+ * Copyright 2005,2006,2011 Free Software Foundation, Inc.
+ * 
+ * This file is part of GNU Radio
+ * 
+ * GNU Radio is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 3, or (at your option)
+ * any later version.
+ * 
+ * GNU Radio is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with GNU Radio; see the file COPYING.  If not, write to
+ * the Free Software Foundation, Inc., 51 Franklin Street,
+ * Boston, MA 02110-1301, USA.
+ */
+
+#ifndef INCLUDED_gr_correlate_access_code_tag_bb_H
+#define INCLUDED_gr_correlate_access_code_tag_bb_H
+
+#include <gr_sync_block.h>
+#include <string>
+
+class gr_correlate_access_code_tag_bb;
+typedef boost::shared_ptr<gr_correlate_access_code_tag_bb> gr_correlate_access_code_tag_bb_sptr;
+
+/*!
+ * \param access_code is represented with 1 byte per bit, e.g., "010101010111000100"
+ * \param threshold maximum number of bits that may be wrong
+ */
+gr_correlate_access_code_tag_bb_sptr 
+gr_make_correlate_access_code_tag_bb (const std::string &access_code, int threshold, const std::string &tag_name);
+
+/*!
+ * \brief Examine input for specified access code, one bit at a time.
+ * \ingroup sync_blk
+ *
+ * input:  stream of bits, 1 bit per input byte (data in LSB)
+ * output: unaltered stream of bits (plus tags)
+ *
+ * This block annotates the input stream with tags. The tags have key name [tag_name],
+ * specified in the constructor. Used for searching an input data stream for preambles, etc.
+ */
+class gr_correlate_access_code_tag_bb : public gr_sync_block
+{
+  friend gr_correlate_access_code_tag_bb_sptr 
+  gr_make_correlate_access_code_tag_bb (const std::string &access_code, int threshold, const std::string &tag_name);
+ private:
+  unsigned long long d_access_code;	// access code to locate start of packet
+                                        //   access code is left justified in the word
+  unsigned long long d_data_reg;	// used to look for access_code
+  unsigned long long d_mask;		// masks access_code bits (top N bits are set where
+                                        //   N is the number of bits in the access code)
+  unsigned int	     d_threshold;	// how many bits may be wrong in sync vector
+  unsigned int       d_len;         //the length of the access code
+
+  pmt::pmt_t d_key, d_me; //d_key is the tag name, d_me is the block name + unique ID
+
+ protected:
+  gr_correlate_access_code_tag_bb(const std::string &access_code, int threshold, const std::string &tag_name);
+
+ public:
+  ~gr_correlate_access_code_tag_bb();
+
+  int work(int noutput_items,
+	   gr_vector_const_void_star &input_items,
+	   gr_vector_void_star &output_items);
+
+  
+  /*!
+   * \param access_code is represented with 1 byte per bit, e.g., "010101010111000100"
+   */
+  bool set_access_code (const std::string &access_code);
+};
+
+#endif /* INCLUDED_gr_correlate_access_code_tag_bb_H */
diff --git a/gnuradio-core/src/lib/general/gr_correlate_access_code_tag_bb.i b/gnuradio-core/src/lib/general/gr_correlate_access_code_tag_bb.i
new file mode 100644
index 000000000..fb832194d
--- /dev/null
+++ b/gnuradio-core/src/lib/general/gr_correlate_access_code_tag_bb.i
@@ -0,0 +1,60 @@
+/* -*- c++ -*- */
+/*
+ * Copyright 2006 Free Software Foundation, Inc.
+ * 
+ * This file is part of GNU Radio
+ * 
+ * GNU Radio is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 3, or (at your option)
+ * any later version.
+ * 
+ * GNU Radio is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with GNU Radio; see the file COPYING.  If not, write to
+ * the Free Software Foundation, Inc., 51 Franklin Street,
+ * Boston, MA 02110-1301, USA.
+ */
+
+GR_SWIG_BLOCK_MAGIC(gr,correlate_access_code_tag_bb);
+
+/*!
+ * \param access_code is represented with 1 byte per bit, e.g., "010101010111000100"
+ * \param threshold maximum number of bits that may be wrong
+ */
+gr_correlate_access_code_tag_bb_sptr 
+gr_make_correlate_access_code_tag_bb (const std::string &access_code, int threshold, const std::string &tag_name) 
+  throw(std::out_of_range);
+
+/*!
+ * \brief Examine input for specified access code, one bit at a time.
+ * \ingroup block
+ *
+ * input:  stream of bits, 1 bit per input byte (data in LSB)
+ * output: stream of bits, 2 bits per output byte (data in LSB, flag in next higher bit)
+ *
+ * Each output byte contains two valid bits, the data bit, and the
+ * flag bit.  The LSB (bit 0) is the data bit, and is the original
+ * input data, delayed 64 bits.  Bit 1 is the
+ * flag bit and is 1 if the corresponding data bit is the first data
+ * bit following the access code. Otherwise the flag bit is 0.
+ */
+class gr_correlate_access_code_tag_bb : public gr_sync_block
+{
+  friend gr_correlate_access_code_tag_bb_sptr 
+  gr_make_correlate_access_code_tag_bb (const std::string &access_code, int threshold, const std::string &tag_name);
+ protected:
+  gr_correlate_access_code_tag_bb(const std::string &access_code, int threshold, const std::string &tag_name);
+
+ public:
+  ~gr_correlate_access_code_tag_bb();
+
+  /*!
+   * \param access_code is represented with 1 byte per bit, e.g., "010101010111000100"
+   */
+  bool set_access_code (const std::string &access_code);
+};