blocks: added gr::blocks::stream_mux

1 files changed, 126 insertions, 0 deletions

diff --git a/gr-blocks/lib/stream_mux_impl.cc b/gr-blocks/lib/stream_mux_impl.cc
new file mode 100644
index 000000000..214734c4b
--- /dev/null
+++ b/gr-blocks/lib/stream_mux_impl.cc
@@ -0,0 +1,126 @@
+/* -*- c++ -*- */
+/*
+ * Copyright 2012 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 "stream_mux_impl.h"
+#include <gr_io_signature.h>
+#include <string.h>
+#include <cstdio>
+
+#define VERBOSE 0
+
+namespace gr {
+  namespace blocks {
+
+    stream_mux::sptr stream_mux::make(size_t itemsize, const std::vector<int> &lengths)
+    {
+      return gnuradio::get_initial_sptr(new stream_mux_impl(itemsize, lengths));
+    }
+
+    stream_mux_impl::stream_mux_impl(size_t itemsize, const std::vector<int> &lengths)
+      : gr_block("stream_mux",
+		 gr_make_io_signature (1, -1, itemsize),
+		 gr_make_io_signature (1, 1, itemsize)),
+	d_itemsize(itemsize),
+	d_stream(0),
+	d_residual(0),
+	d_lengths(lengths)
+    {
+      if(d_lengths[d_stream] == 0) {
+	increment_stream();
+      }
+      d_residual = d_lengths[d_stream];
+    }
+
+    void
+    stream_mux_impl::forecast(int noutput_items, gr_vector_int &ninput_items_required)
+    {
+      unsigned ninputs = ninput_items_required.size ();
+      for (unsigned i = 0; i < ninputs; i++)
+	ninput_items_required[i] = (d_lengths[i] == 0 ? 0 : 1);
+    }
+
+    void 
+    stream_mux_impl::increment_stream()
+    {
+      do {
+	d_stream = (d_stream+1) % d_lengths.size();
+      } while(d_lengths[d_stream] == 0);
+      
+      d_residual = d_lengths[d_stream];
+    }
+
+
+    int
+    stream_mux_impl::general_work(int noutput_items,
+				   gr_vector_int &ninput_items,
+				   gr_vector_const_void_star &input_items,
+				   gr_vector_void_star &output_items)
+    {
+      char *out = (char *) output_items[0];
+      const char *in;
+      int out_index = 0;
+      std::vector<int> input_index(d_lengths.size(), 0);
+      
+      if(VERBOSE) {
+	printf("mux: nouput_items: %d   d_stream: %d\n", noutput_items, d_stream);
+	for(size_t i = 0; i < d_lengths.size(); i++)
+	  printf("\tninput_items[%zu]: %d\n", i, ninput_items[i]);
+      }
+      
+      while (1) {
+	int r = std::min(noutput_items - out_index,
+			 std::min(d_residual,
+				  ninput_items[d_stream] - input_index[d_stream]));
+	if(VERBOSE) {
+	  printf("mux: r=%d\n", r);
+	  printf("\tnoutput_items - out_index: %d\n",
+		 noutput_items - out_index);
+	  printf("\td_residual: %d\n",
+		 d_residual);
+	  printf("\tninput_items[d_stream] - input_index[d_stream]: %d\n",
+		 ninput_items[d_stream] - input_index[d_stream]);
+	}
+	
+	if(r <= 0) {
+	  return out_index;
+	}
+	
+	in = (const char *) input_items[d_stream] + input_index[d_stream]*d_itemsize;
+	
+	memcpy(&out[out_index*d_itemsize], in, r*d_itemsize);
+	out_index += r;
+	input_index[d_stream] += r;
+	d_residual -= r;
+	
+	consume(d_stream, r);
+	
+	if(d_residual == 0) {
+	  increment_stream();
+	}
+      }
+    }
+  } /* namespace blocks */
+} /* namespace gr */