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diff --git a/lib/edi/common.cpp b/lib/edi/common.cpp
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+/*
+ Copyright (C) 2019
+ Matthias P. Braendli, matthias.braendli@mpb.li
+
+ http://opendigitalradio.org
+
+ This program 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 2 of the License, or
+ (at your option) any later version.
+
+ This program 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 program; if not, write to the Free Software Foundation, Inc.,
+ 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+#include "common.hpp"
+#include "buffer_unpack.hpp"
+#include "Log.h"
+#include "crc.h"
+#include <iomanip>
+#include <sstream>
+#include <cassert>
+#include <cstdio>
+
+namespace EdiDecoder {
+
+using namespace std;
+
+string frame_timestamp_t::to_string() const
+{
+ const time_t seconds_in_unix_epoch = to_unix_epoch();
+
+ stringstream ss;
+ ss << "Timestamp: " << std::put_time(std::gmtime(&seconds_in_unix_epoch), "%c %Z");
+ return ss.str();
+}
+
+time_t frame_timestamp_t::to_unix_epoch() const
+{
+ // EDI epoch: 2000-01-01T00:00:00Z
+ // Convert using
+ // TZ=UTC python -c 'import datetime; print(datetime.datetime(2000,1,1,0,0,0,0).strftime("%s"))'
+ return 946684800 + seconds - utco;
+}
+
+
+TagDispatcher::TagDispatcher(
+ std::function<void()>&& af_packet_completed, bool verbose) :
+ m_af_packet_completed(move(af_packet_completed))
+{
+ m_pft.setVerbose(verbose);
+}
+
+void TagDispatcher::push_bytes(const vector<uint8_t> &buf)
+{
+ copy(buf.begin(), buf.end(), back_inserter(m_input_data));
+
+ while (m_input_data.size() > 2) {
+ if (m_input_data[0] == 'A' and m_input_data[1] == 'F') {
+ const decode_state_t st = decode_afpacket(m_input_data);
+
+ if (st.num_bytes_consumed == 0 and not st.complete) {
+ // We need to refill our buffer
+ break;
+ }
+
+ if (st.num_bytes_consumed) {
+ vector<uint8_t> remaining_data;
+ copy(m_input_data.begin() + st.num_bytes_consumed,
+ m_input_data.end(),
+ back_inserter(remaining_data));
+ m_input_data = remaining_data;
+ }
+
+ if (st.complete) {
+ m_af_packet_completed();
+ }
+ }
+ else if (m_input_data[0] == 'P' and m_input_data[1] == 'F') {
+ PFT::Fragment fragment;
+ const size_t fragment_bytes = fragment.loadData(m_input_data);
+
+ if (fragment_bytes == 0) {
+ // We need to refill our buffer
+ break;
+ }
+
+ vector<uint8_t> remaining_data;
+ copy(m_input_data.begin() + fragment_bytes,
+ m_input_data.end(),
+ back_inserter(remaining_data));
+ m_input_data = remaining_data;
+
+ if (fragment.isValid()) {
+ m_pft.pushPFTFrag(fragment);
+ }
+
+ auto af = m_pft.getNextAFPacket();
+ if (not af.empty()) {
+ decode_state_t st = decode_afpacket(af);
+
+ if (st.complete) {
+ m_af_packet_completed();
+ }
+ }
+ }
+ else {
+ etiLog.log(warn,"Unknown %c!", *m_input_data.data());
+ m_input_data.erase(m_input_data.begin());
+ }
+ }
+}
+
+void TagDispatcher::push_packet(const vector<uint8_t> &buf)
+{
+ if (buf.size() < 2) {
+ throw std::invalid_argument("Not enough bytes to read EDI packet header");
+ }
+
+ if (buf[0] == 'A' and buf[1] == 'F') {
+ const decode_state_t st = decode_afpacket(buf);
+
+ if (st.complete) {
+ m_af_packet_completed();
+ }
+
+ }
+ else if (buf[0] == 'P' and buf[1] == 'F') {
+ PFT::Fragment fragment;
+ fragment.loadData(buf);
+
+ if (fragment.isValid()) {
+ m_pft.pushPFTFrag(fragment);
+ }
+
+ auto af = m_pft.getNextAFPacket();
+ if (not af.empty()) {
+ const decode_state_t st = decode_afpacket(af);
+
+ if (st.complete) {
+ m_af_packet_completed();
+ }
+ }
+ }
+ else {
+ const char packettype[3] = {(char)buf[0], (char)buf[1], '\0'};
+ std::stringstream ss;
+ ss << "Unknown EDI packet ";
+ ss << packettype;
+ throw std::invalid_argument(ss.str());
+ }
+}
+
+void TagDispatcher::setMaxDelay(int num_af_packets)
+{
+ m_pft.setMaxDelay(num_af_packets);
+}
+
+
+#define AFPACKET_HEADER_LEN 10 // includes SYNC
+decode_state_t TagDispatcher::decode_afpacket(
+ const std::vector<uint8_t> &input_data)
+{
+ if (input_data.size() < AFPACKET_HEADER_LEN) {
+ return {false, 0};
+ }
+
+ // read length from packet
+ uint32_t taglength = read_32b(input_data.begin() + 2);
+ uint16_t seq = read_16b(input_data.begin() + 6);
+
+ const size_t crclength = 2;
+ if (input_data.size() < AFPACKET_HEADER_LEN + taglength + crclength) {
+ return {false, 0};
+ }
+
+ if (m_last_seq + 1 != seq) {
+ etiLog.level(warn) << "EDI AF Packet sequence error, " << seq;
+ }
+ m_last_seq = seq;
+
+ bool has_crc = (input_data[8] & 0x80) ? true : false;
+ uint8_t major_revision = (input_data[8] & 0x70) >> 4;
+ uint8_t minor_revision = input_data[8] & 0x0F;
+ if (major_revision != 1 or minor_revision != 0) {
+ throw invalid_argument("EDI AF Packet has wrong revision " +
+ to_string(major_revision) + "." + to_string(minor_revision));
+ }
+ uint8_t pt = input_data[9];
+ if (pt != 'T') {
+ // only support Tag
+ return {false, 0};
+ }
+
+
+ if (not has_crc) {
+ throw invalid_argument("AF packet not supported, has no CRC");
+ }
+
+ uint16_t crc = 0xffff;
+ for (size_t i = 0; i < AFPACKET_HEADER_LEN + taglength; i++) {
+ crc = crc16(crc, &input_data[i], 1);
+ }
+ crc ^= 0xffff;
+
+ uint16_t packet_crc = read_16b(input_data.begin() + AFPACKET_HEADER_LEN + taglength);
+
+ if (packet_crc != crc) {
+ throw invalid_argument(
+ "AF Packet crc wrong");
+ }
+ else {
+ vector<uint8_t> payload(taglength);
+ copy(input_data.begin() + AFPACKET_HEADER_LEN,
+ input_data.begin() + AFPACKET_HEADER_LEN + taglength,
+ payload.begin());
+
+ return {decode_tagpacket(payload),
+ AFPACKET_HEADER_LEN + taglength + 2};
+ }
+}
+
+void TagDispatcher::register_tag(const std::string& tag, tag_handler&& h)
+{
+ m_handlers[tag] = move(h);
+}
+
+
+bool TagDispatcher::decode_tagpacket(const vector<uint8_t> &payload)
+{
+ size_t length = 0;
+
+ bool success = true;
+
+ for (size_t i = 0; i + 8 < payload.size(); i += 8 + length) {
+ char tag_sz[5];
+ tag_sz[4] = '\0';
+ copy(payload.begin() + i, payload.begin() + i + 4, tag_sz);
+
+ string tag(tag_sz);
+
+ uint32_t taglength = read_32b(payload.begin() + i + 4);
+
+ if (taglength % 8 != 0) {
+ etiLog.log(warn, "Invalid tag length!");
+ break;
+ }
+ taglength /= 8;
+
+ length = taglength;
+
+ vector<uint8_t> tag_value(taglength);
+ copy( payload.begin() + i+8,
+ payload.begin() + i+8+taglength,
+ tag_value.begin());
+
+ bool tagsuccess = false;
+ bool found = false;
+ for (auto tag_handler : m_handlers) {
+ if (tag_handler.first.size() == 4 and tag_handler.first == tag) {
+ found = true;
+ tagsuccess = tag_handler.second(tag_value, 0);
+ }
+ else if (tag_handler.first.size() == 3 and
+ tag.substr(0, 3) == tag_handler.first) {
+ found = true;
+ uint8_t n = tag_sz[3];
+ tagsuccess = tag_handler.second(tag_value, n);
+ }
+ else if (tag_handler.first.size() == 2 and
+ tag.substr(0, 2) == tag_handler.first) {
+ found = true;
+ uint16_t n = 0;
+ n = (uint16_t)(tag_sz[2]) << 8;
+ n |= (uint16_t)(tag_sz[3]);
+ tagsuccess = tag_handler.second(tag_value, n);
+ }
+ }
+
+ if (not found) {
+ etiLog.log(warn, "Ignoring unknown TAG %s", tag.c_str());
+ break;
+ }
+
+ if (not tagsuccess) {
+ etiLog.log(warn, "Error decoding TAG %s", tag.c_str());
+ success = tagsuccess;
+ break;
+ }
+ }
+
+ return success;
+}
+
+}