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Diffstat (limited to 'gr-digital/lib/framer_sink_1_impl.h')
| -rw-r--r-- | gr-digital/lib/framer_sink_1_impl.h | 83 |
1 files changed, 83 insertions, 0 deletions
diff --git a/gr-digital/lib/framer_sink_1_impl.h b/gr-digital/lib/framer_sink_1_impl.h new file mode 100644 index 0000000000..ff2839acbf --- /dev/null +++ b/gr-digital/lib/framer_sink_1_impl.h @@ -0,0 +1,83 @@ +/* -*- c++ -*- */ +/* + * Copyright 2005,2006,2012 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. + */ + +#ifndef INCLUDED_GR_FRAMER_SINK_1_IMPL_H +#define INCLUDED_GR_FRAMER_SINK_1_IMPL_H + +#include <digital/framer_sink_1.h> + +namespace gr { + namespace digital { + + class framer_sink_1_impl : public framer_sink_1 + { + private: + enum state_t {STATE_SYNC_SEARCH, STATE_HAVE_SYNC, STATE_HAVE_HEADER}; + + static const int MAX_PKT_LEN = 4096; + static const int HEADERBITLEN = 32; + + gr_msg_queue_sptr d_target_queue; // where to send the packet when received + state_t d_state; + unsigned int d_header; // header bits + int d_headerbitlen_cnt; // how many so far + + unsigned char d_packet[MAX_PKT_LEN]; // assembled payload + unsigned char d_packet_byte; // byte being assembled + int d_packet_byte_index; // which bit of d_packet_byte we're working on + int d_packetlen; // length of packet + int d_packet_whitener_offset; // offset into whitener string to use + int d_packetlen_cnt; // how many so far + + protected: + void enter_search(); + void enter_have_sync(); + void enter_have_header(int payload_len, int whitener_offset); + + bool header_ok() + { + // confirm that two copies of header info are identical + return ((d_header >> 16) ^ (d_header & 0xffff)) == 0; + } + + void header_payload(int *len, int *offset) + { + // header consists of two 16-bit shorts in network byte order + // payload length is lower 12 bits + // whitener offset is upper 4 bits + *len = (d_header >> 16) & 0x0fff; + *offset = (d_header >> 28) & 0x000f; + } + + public: + framer_sink_1_impl(gr_msg_queue_sptr target_queue); + ~framer_sink_1_impl(); + + int work(int noutput_items, + gr_vector_const_void_star &input_items, + gr_vector_void_star &output_items); + }; + + } /* namespace digital */ +} /* namespace gr */ + +#endif /* INCLUDED_GR_FRAMER_SINK_1_IMPL_H */ |