1 files changed, 120 insertions, 0 deletions
diff --git a/gr-fec/lib/decoder_impl.cc b/gr-fec/lib/decoder_impl.cc
new file mode 100644
index 0000000000..ba8a7d000e
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+++ b/gr-fec/lib/decoder_impl.cc
@@ -0,0 +1,120 @@
+/* -*- c++ -*- */
+/*
+ * Copyright 2013-2014 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 "decoder_impl.h"
+#include <gnuradio/io_signature.h>
+#include <stdio.h>
+
+namespace gr {
+  namespace fec {
+
+    decoder::sptr
+    decoder::make(generic_decoder::sptr my_decoder,
+                  size_t input_item_size,
+                  size_t output_item_size)
+    {
+      return gnuradio::get_initial_sptr
+        ( new decoder_impl(my_decoder, input_item_size, output_item_size));
+    }
+
+    decoder_impl::decoder_impl(generic_decoder::sptr my_decoder,
+                               size_t input_item_size,
+                               size_t output_item_size)
+      : block("fec_decoder",
+              io_signature::make(1, 1, input_item_size),
+              io_signature::make(1, 1, output_item_size)),
+        d_input_item_size(input_item_size), d_output_item_size(output_item_size)
+    {
+      set_fixed_rate(true);
+      set_relative_rate((double)(my_decoder->get_output_size())/my_decoder->get_input_size());
+
+      //want to guarantee you have enough to run at least one time...
+      //remember! this is not a sync block... set_output_multiple does not
+      //actually guarantee the output multiple... it DOES guarantee how many
+      //outputs (hence inputs) are made available... this is WEIRD to do in
+      //GNU Radio, and the algorithm is sensitive to this value
+      set_output_multiple(my_decoder->get_output_size() + (my_decoder->get_history()));
+      d_decoder = my_decoder;
+    }
+
+    int
+    decoder_impl::fixed_rate_ninput_to_noutput(int ninput)
+    {
+      return (int)(0.5 + ninput*relative_rate());
+    }
+
+    int
+    decoder_impl::fixed_rate_noutput_to_ninput(int noutput)
+    {
+      return (int)(0.5 + noutput/relative_rate());
+    }
+
+    void
+    decoder_impl::forecast(int noutput_items,
+                           gr_vector_int& ninput_items_required)
+    {
+      ninput_items_required[0] = 0.5 + fixed_rate_noutput_to_ninput(noutput_items);
+    }
+
+    int
+    decoder_impl::general_work(int noutput_items,
+                               gr_vector_int& ninput_items,
+                               gr_vector_const_void_star &input_items,
+                               gr_vector_void_star &output_items)
+    {
+      const unsigned char *in = (unsigned char*)input_items[0];
+      unsigned char *out = (unsigned char *)output_items[0];
+
+      int outnum = (int)(((1.0/relative_rate()) * noutput_items) + 0.5);
+      int innum = (int)(relative_rate() * (ninput_items[0] - d_decoder->get_history()) + 0.5)/(output_multiple() - d_decoder->get_history());
+
+      int items = (outnum <= ninput_items[0] - d_decoder->get_history()) ?
+	noutput_items/(output_multiple() - d_decoder->get_history()) :
+	innum;
+
+      GR_LOG_DEBUG(d_debug_logger, boost::format("%1%, %2%, %3%")      \
+                   % outnum % ninput_items[0] % items);
+
+      for(int i = 0; i < items; ++i) {
+        d_decoder->generic_work((void*)(in+(i*d_decoder->get_input_size()*d_input_item_size)),
+                                (void*)(out+(i*d_decoder->get_output_size()*d_output_item_size)));
+
+        add_item_tag(0, nitems_written(0) + ((i+1)*d_decoder->get_output_size()*d_output_item_size),
+                     pmt::intern(d_decoder->alias()), pmt::PMT_T, pmt::intern(alias()));
+      }
+
+      int consumed = static_cast<int>(items/relative_rate()*(output_multiple() - d_decoder->get_history()) + 0.5);
+      int returned = items*(output_multiple() - d_decoder->get_history());
+
+      GR_LOG_DEBUG(d_debug_logger, boost::format("consumed %1%") % consumed);
+      GR_LOG_DEBUG(d_debug_logger, boost::format("returned %1%") % returned);
+
+      consume_each(consumed);
+      return returned;
+    }
+
+  } /* namespace fec */
+} /* namespace gr */