Added new configurable block for demapping of control channels.
diff --git a/lib/demapping/universal_ctrl_chans_demapper_impl.cc b/lib/demapping/universal_ctrl_chans_demapper_impl.cc
new file mode 100644
index 0000000..ea9a06e
--- /dev/null
+++ b/lib/demapping/universal_ctrl_chans_demapper_impl.cc
@@ -0,0 +1,135 @@
+/* -*- c++ -*- */
+/*
+ * Copyright 2014 <+YOU OR YOUR COMPANY+>.
+ *
+ * This 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.
+ *
+ * This software 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 this software; 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 <gnuradio/io_signature.h>
+#include "universal_ctrl_chans_demapper_impl.h"
+#include <gsm/gsmtap.h>
+
+namespace gr {
+ namespace gsm {
+
+ universal_ctrl_chans_demapper::sptr
+ universal_ctrl_chans_demapper::make(const std::vector<int> &starts_fn_mod51, const std::vector<int> &channel_types)
+ {
+ return gnuradio::get_initial_sptr
+ (new universal_ctrl_chans_demapper_impl(starts_fn_mod51, channel_types));
+ }
+
+ /*
+ * The private constructor
+ */
+ universal_ctrl_chans_demapper_impl::universal_ctrl_chans_demapper_impl(const std::vector<int> &starts_fn_mod51, const std::vector<int> &channel_types)
+ : gr::block("universal_ctrl_chans_demapper",
+ gr::io_signature::make(0, 0, 0),
+ gr::io_signature::make(0, 0, 0))
+ {
+
+ d_timeslot=0;
+ for(int ii=0; ii<51; ii++)
+ {
+ d_starts_fn_mod51[ii]=0;
+ d_channel_types[ii]=0;
+ }
+
+ std::vector<int>::const_iterator s;
+ std::vector<int>::const_iterator ch_type;
+
+ for(s=starts_fn_mod51.begin(), ch_type=channel_types.begin();s != starts_fn_mod51.end(); s++)
+ {
+ if((*s > 0) and (*s < (51-4)))
+ {
+ for(int ii=0; ii<4; ii++){
+ d_starts_fn_mod51[*s+ii] = *s;
+ if(ch_type!=channel_types.end())
+ {
+ d_channel_types[*s+ii] = *ch_type;
+ }
+ }
+ if(ch_type!=channel_types.end())
+ {
+ ch_type++;
+ }
+ }
+ }
+
+
+ message_port_register_in(pmt::mp("bursts"));
+ set_msg_handler(pmt::mp("bursts"), boost::bind(&universal_ctrl_chans_demapper_impl::filter_ctrl_chans, this, _1));
+ message_port_register_out(pmt::mp("bursts"));
+ }
+
+ /*
+ * Our virtual destructor.
+ */
+ universal_ctrl_chans_demapper_impl::~universal_ctrl_chans_demapper_impl()
+ {
+ }
+
+ void universal_ctrl_chans_demapper_impl::filter_ctrl_chans(pmt::pmt_t msg)
+ {
+ pmt::pmt_t header_blob = pmt::car(msg);
+ pmt::pmt_t content = pmt::cdr(msg);
+ gsmtap_hdr * header = (gsmtap_hdr *)pmt::blob_data(header_blob);
+ uint32_t frame_nr = be32toh(header->frame_number);
+
+ uint32_t fn_mod51 = frame_nr % 51;
+ uint32_t fn51_start = d_starts_fn_mod51[fn_mod51];
+ uint32_t fn51_stop = fn51_start + 3;
+ uint32_t ch_type = d_channel_types[fn_mod51];
+ header->sub_type = ch_type;
+
+ if(header->timeslot==d_timeslot){
+ if(fn_mod51>=fn51_start && fn_mod51<=fn51_stop)
+ {
+ uint32_t ii = fn_mod51 - fn51_start;
+ d_frame_numbers[ii] = frame_nr;
+ d_bursts[ii] = msg;
+ }
+
+ if(fn_mod51==fn51_stop)
+ {
+ //check for a situation where some bursts were lost
+ //in this situation frame numbers won't be consecutive
+ bool frames_are_consecutive = true;
+ for(int jj=1; jj<4; jj++)
+ {
+ if((d_frame_numbers[jj]-d_frame_numbers[jj-1])!=1)
+ {
+ frames_are_consecutive = false;
+ }
+ }
+ if(frames_are_consecutive)
+ {
+ //send bursts to the output
+ for(int jj=0; jj<4; jj++)
+ {
+ message_port_pub(pmt::mp("bursts"), d_bursts[jj]);
+ }
+ }
+ }
+ }
+ }
+ } /* namespace gsm */
+} /* namespace gr */
+
diff --git a/lib/demapping/universal_ctrl_chans_demapper_impl.h b/lib/demapping/universal_ctrl_chans_demapper_impl.h
new file mode 100644
index 0000000..472b321
--- /dev/null
+++ b/lib/demapping/universal_ctrl_chans_demapper_impl.h
@@ -0,0 +1,48 @@
+/* -*- c++ -*- */
+/*
+ * Copyright 2014 <+YOU OR YOUR COMPANY+>.
+ *
+ * This 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.
+ *
+ * This software 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 this software; see the file COPYING. If not, write to
+ * the Free Software Foundation, Inc., 51 Franklin Street,
+ * Boston, MA 02110-1301, USA.
+ */
+
+#ifndef INCLUDED_GSM_UNIVERSAL_CTRL_CHANS_DEMAPPER_IMPL_H
+#define INCLUDED_GSM_UNIVERSAL_CTRL_CHANS_DEMAPPER_IMPL_H
+
+#include <gsm/demapping/universal_ctrl_chans_demapper.h>
+
+namespace gr {
+ namespace gsm {
+
+ class universal_ctrl_chans_demapper_impl : public universal_ctrl_chans_demapper
+ {
+ private:
+ unsigned int d_starts_fn_mod51[51];
+ unsigned int d_channel_types[51];
+ unsigned int d_timeslot;
+ uint32_t d_frame_numbers[4];
+ pmt::pmt_t d_bursts[4];
+ public:
+ universal_ctrl_chans_demapper_impl(const std::vector<int> &starts_fn_mod51, const std::vector<int> &channel_types);
+ ~universal_ctrl_chans_demapper_impl();
+
+ void filter_ctrl_chans(pmt::pmt_t msg);
+ };
+
+ } // namespace gsm
+} // namespace gr
+
+#endif /* INCLUDED_GSM_UNIVERSAL_CTRL_CHANS_DEMAPPER_IMPL_H */
+