piotr | faacc72 | 2014-07-20 23:48:32 +0200 | [diff] [blame] | 1 | /* -*- c++ -*- */ |
ptrkrysik | 529895b | 2014-12-02 18:07:38 +0100 | [diff] [blame] | 2 | /* |
| 3 | * @file |
| 4 | * @author Piotr Krysik <ptrkrysik@gmail.com> |
| 5 | * @section LICENSE |
| 6 | * |
| 7 | * Gr-gsm is free software; you can redistribute it and/or modify |
piotr | faacc72 | 2014-07-20 23:48:32 +0200 | [diff] [blame] | 8 | * it under the terms of the GNU General Public License as published by |
| 9 | * the Free Software Foundation; either version 3, or (at your option) |
| 10 | * any later version. |
ptrkrysik | 529895b | 2014-12-02 18:07:38 +0100 | [diff] [blame] | 11 | * |
| 12 | * Gr-gsm is distributed in the hope that it will be useful, |
piotr | faacc72 | 2014-07-20 23:48:32 +0200 | [diff] [blame] | 13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 15 | * GNU General Public License for more details. |
ptrkrysik | 529895b | 2014-12-02 18:07:38 +0100 | [diff] [blame] | 16 | * |
piotr | faacc72 | 2014-07-20 23:48:32 +0200 | [diff] [blame] | 17 | * You should have received a copy of the GNU General Public License |
ptrkrysik | 529895b | 2014-12-02 18:07:38 +0100 | [diff] [blame] | 18 | * along with gr-gsm; see the file COPYING. If not, write to |
piotr | faacc72 | 2014-07-20 23:48:32 +0200 | [diff] [blame] | 19 | * the Free Software Foundation, Inc., 51 Franklin Street, |
| 20 | * Boston, MA 02110-1301, USA. |
| 21 | */ |
| 22 | |
| 23 | #ifdef HAVE_CONFIG_H |
| 24 | #include "config.h" |
| 25 | #endif |
| 26 | |
| 27 | #include <gnuradio/io_signature.h> |
David Holm | 9880653 | 2014-12-01 21:19:18 +0100 | [diff] [blame] | 28 | #include <gsm/endian.h> |
piotr | faacc72 | 2014-07-20 23:48:32 +0200 | [diff] [blame] | 29 | #include <gsm/gsmtap.h> |
| 30 | #include "get_bcch_or_ccch_bursts_impl.h" |
| 31 | |
| 32 | namespace gr { |
| 33 | namespace gsm { |
| 34 | |
| 35 | get_bcch_or_ccch_bursts::sptr |
piotr | df30459 | 2014-08-04 11:22:47 +0200 | [diff] [blame] | 36 | get_bcch_or_ccch_bursts::make(unsigned int fn51_start) |
piotr | faacc72 | 2014-07-20 23:48:32 +0200 | [diff] [blame] | 37 | { |
| 38 | return gnuradio::get_initial_sptr |
piotr | df30459 | 2014-08-04 11:22:47 +0200 | [diff] [blame] | 39 | (new get_bcch_or_ccch_bursts_impl(fn51_start)); |
piotr | faacc72 | 2014-07-20 23:48:32 +0200 | [diff] [blame] | 40 | } |
| 41 | |
| 42 | /* |
| 43 | * The private constructor |
| 44 | */ |
piotr | df30459 | 2014-08-04 11:22:47 +0200 | [diff] [blame] | 45 | get_bcch_or_ccch_bursts_impl::get_bcch_or_ccch_bursts_impl(unsigned int fn51_start) |
piotr | faacc72 | 2014-07-20 23:48:32 +0200 | [diff] [blame] | 46 | : gr::block("get_bcch_or_ccch_bursts", |
| 47 | gr::io_signature::make(0, 0, 0), |
piotr | df30459 | 2014-08-04 11:22:47 +0200 | [diff] [blame] | 48 | gr::io_signature::make(0, 0, 0)), |
| 49 | d_fn51_start(fn51_start) |
piotr | faacc72 | 2014-07-20 23:48:32 +0200 | [diff] [blame] | 50 | { |
| 51 | message_port_register_in(pmt::mp("bursts")); |
| 52 | set_msg_handler(pmt::mp("bursts"), boost::bind(&get_bcch_or_ccch_bursts_impl::filter_ccch, this, _1)); |
| 53 | message_port_register_out(pmt::mp("bursts")); |
| 54 | } |
| 55 | |
| 56 | /* |
| 57 | * Our virtual destructor. |
| 58 | */ |
| 59 | get_bcch_or_ccch_bursts_impl::~get_bcch_or_ccch_bursts_impl() |
| 60 | { |
| 61 | } |
| 62 | |
| 63 | void get_bcch_or_ccch_bursts_impl::filter_ccch(pmt::pmt_t msg) |
| 64 | { |
ptrkrysik | 617ba03 | 2014-11-21 10:11:05 +0100 | [diff] [blame] | 65 | pmt::pmt_t header_plus_burst = pmt::cdr(msg); |
| 66 | gsmtap_hdr * header = (gsmtap_hdr *)pmt::blob_data(header_plus_burst); |
ptrkrysik | 6f6d46d | 2014-11-12 22:50:18 +0100 | [diff] [blame] | 67 | uint32_t frame_nr = be32toh(header->frame_number); |
piotr | faacc72 | 2014-07-20 23:48:32 +0200 | [diff] [blame] | 68 | |
ptrkrysik | 6f6d46d | 2014-11-12 22:50:18 +0100 | [diff] [blame] | 69 | uint32_t fn_mod51 = frame_nr % 51; |
piotr | df30459 | 2014-08-04 11:22:47 +0200 | [diff] [blame] | 70 | int fn51_stop = d_fn51_start+3; |
piotr | faacc72 | 2014-07-20 23:48:32 +0200 | [diff] [blame] | 71 | |
| 72 | if(header->timeslot==0){ |
piotr | df30459 | 2014-08-04 11:22:47 +0200 | [diff] [blame] | 73 | if(fn_mod51>=d_fn51_start && fn_mod51<=fn51_stop){ |
| 74 | uint32_t ii = fn_mod51-d_fn51_start; |
ptrkrysik | 6f6d46d | 2014-11-12 22:50:18 +0100 | [diff] [blame] | 75 | d_frame_numbers[ii]=frame_nr; |
piotr | faacc72 | 2014-07-20 23:48:32 +0200 | [diff] [blame] | 76 | d_bursts[ii] = msg; |
| 77 | } |
| 78 | |
| 79 | if(fn_mod51==fn51_stop){ |
| 80 | //check for a situation where some BCCH bursts were lost |
| 81 | //in this situation frame numbers won't be consecutive |
| 82 | bool frames_are_consecutive = true; |
| 83 | for(int jj=1; jj<4; jj++) |
| 84 | { |
| 85 | if((d_frame_numbers[jj]-d_frame_numbers[jj-1])!=1){ |
| 86 | frames_are_consecutive = false; |
| 87 | } |
| 88 | } |
| 89 | if(frames_are_consecutive) |
| 90 | { |
| 91 | //send bursts to the output |
| 92 | for(int jj=0; jj<4; jj++) |
| 93 | { |
| 94 | message_port_pub(pmt::mp("bursts"), d_bursts[jj]); |
| 95 | } |
| 96 | } |
| 97 | } |
| 98 | } |
| 99 | } |
| 100 | } /* namespace gsm */ |
| 101 | } /* namespace gr */ |
| 102 | |